The invention provides improved agents and methods for treatment of diseases associated with amyloid deposits of Axcex2 in the brain of a patient. Such methods entail administering agents that induce a beneficial immunogenic response against the amyloid deposit. The methods are useful for prophylactic and therapeutic treatment of Alzheimer""s disease. Preferred agents including N-terminal fragments of Axcex2 and antibodies binding to the same.

The invention resides in the technical fields of immunology and medicine.
Alzheimer""s disease (AD) is a progressive disease resulting in senile dementia. See generally Selkoe, TINS 16, 403-409 (1993); Hardy et al., WO 92/13069; Selkoe, J. Neuropathol. Exp. Neurol. 53, 438-447 (1994); Duff et al., Nature 373, 476-477 (1995); Games et al., Nature 373, 523 (1995). Broadly speaking, the disease falls into two categories: late onset, which occurs in old age (65+years) and early onset, which develops well before the senile period, i.e., between 35 and 60 years. In both types of disease, the pathology is the sarre but the abnormalities tend to be more severe and widespread in cases beginning at an earlier age. The disease is characterized by at least two types of lesions in the brain, senile plaques and neurofibrillary tangles. Senile plaques are areas of disorganized neuropil up to 150 xcexcm across with extracellular amyloid deposits at the center visible by microscopic analysis of sections of brain tissue. Neurofibrillary tangles are intracellular deposits of microtubule associated tau protein consisting of two filaments twisted about each other in pairs.
The principal constituent of the plaques is a peptide termed Axcex2 or xcex2-amyloid peptide. Axcex2 peptide is an internal fragment of 39-43 amino acids of a precursor protein termed amyloid precursor protein (APP). Several mutations within the APP protein have been correlated with the presence of Alzheimer""s disease. See, e.g., Goate et al., Nature 349, 704) (1991) (valine717 to isoleucine); Chartier Harlan et al. Nature 353, 844 (1991)) (valine717 to glycine); Murrell et al., Science 254, 97 (1991) (valine717 to phenylalanine); Mullan et al., Nature Genet. 1, 345 (1992) (a double mutation changing lysine595-methionine596 to asparagine595-leucine596). Such mutations are thought to cause Alzheimer""s disease by increased or altered processing of APP to Axcex2, particularly processing of APP to increased amounts of the long form of Axcex2 (i.e., Axcex21-42 and Axcex21-43). Mutations in other genes, such as the presenilin genes, PS1 and PS2, are thought indirectly to affect processing of APP to generate increased amounts of long form Axcex2 (see Hardy, TINS 20, 154 (1997)). These observations indicate that Axcex2, and particularly its long form, is a causative element in Alzheimer""s disease.
McMichael, EP 526,511, proposes administration of homeopathic dosages (less than or equal to 10xe2x88x922 mg/day) of Axcex2 to patients with preestablished AD. In a typical human with about 5 liters of plasma, even the upper limit of this dosage would be expected to generate a concentration of no more than 2 pg/ml. The normal concentration of Axcex2 in human plasma is typically in the range of 50-200 pg/ml (Seubert et al., Nature 359, 325-327 (1992)). Because EP 526,511""s proposed dosage would barely alter the level of endogenous circulating Axcex2 and because EP 526,511 does not recommend use of an adjuvant, as an immunostimulant, it seems implausible that any therapeutic benefit would result.
By contrast, the present invention is directed inter alia to treatment of Alzheimer""s and other anyloidogenic diseases by administration of fragments of Axcex2, or antibody to certain epitopes within Axcex2 to a patient under conditions that generate a beneficial immune response in the patient. The invention thus fulfills a longstanding need for therapeutic regimes for preventing or ameliorating the neuropathology and, in some patients, the cognitive impairment associated with Alzheimer""s disease.
This application is related to International Application No. PCT/US00/14810 filed May 26, 2000, Publication No. WO 00/72880; U.S. application Ser. No. 322,289, filed May 28 1999; PCT/US98/25386, filed Nov. 30, 1998, Publication No. WO 99/27944; U.S. application Ser. No. 09/201,430, filed Nov. 30, 1998; U.S. Application No. 60/067,740, filed Dec. 2, 1997; and, U.S. Application No., filed Apr. 7, 1998; each of which is incorporated by reference in its entirety for all purposes.
In one aspect, the invention provides methods of preventing or treating a disease associated with amyloid deposits of Axcex2 in the brain of a patient. Such diseases include Alzheimer""s disease, Down""s syndrome and cognitive impairment. The latter can occur with or without other characteristics of an amyloidogenic disease. Some methods of the invention entail administering an effective dosage of an antibody that specifically binds to a component of an amyloid deposit to the patient. Such methods are particularly useful for preventing or treating Alzheimer""s disease in human patients. Some methods entail administering an effective dosage of an antibody that binds to Axcex2. Some methods entail administering an effective dosage of an antibody that specifically binds to an epitope within residues 1-10 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 1-6 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 1-5 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 1-7 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 3-7 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 1-3 of Axcex2. In some methods, the antibody specifically binds to an epitope within residues 1-4 of Axcex2. In some methods, the antibody binds to an epitope comprising a free N-terminal residue of Axcex2. In some methods, the antibody binds to an epitope within residues of 1-10 of Axcex2 wherein residue 1 and/or residue 7 of Axcex2 is aspartic acid. In some methods, the antibody specifically binds to Axcex2 peptide without binding to full-length amyloid precursor protein (APP). In some methods, the isotype of the antibody is human IgG1.
In some methods, the antibody binds to an amyloid deposit in the patient and induces a clearing response against the amyloid deposit. For example, such a clearing response can be effected by Fc receptor mediated phagocytosis.
The methods can be used on both asymptomatic patients and those currently showing symptoms of disease. The antibody used in such methods can be a human, humanized, chimeric or nonhuman antibody and can be monoclonal or polyclonal. In some methods, the antibody is prepared from a human immunized with Axcex2 peptide, which human can be the patient to be treated with antibody.
In some methods, the antibody is administered with a pharmaceutical carrier as a pharmaceutical composition. In some methods, antibody is administered at a dosage of 0.0001 to 100 mg/kg, preferably, at least 1 mg/kg body weight antibody. In some methods, the antibody is administered in multiple dosages over a prolonged period, for example, of at least six months. In some methods, the antibody is administered as a sustained release composition. The antibody can be administered, for example, intraperitoneally, orally, subcutaneously, intracranially, intramuscularly, topically, intranasally or intravenously.
In some methods, the antibody is administered by administering a polynucleotide encoding at least one antibody chain to the patient. The polynucleotide is expressed to produce the antibody chain in the patient. Optionally, the polynucleotide encodes heavy and light chains of the antibody. The polynucleotide is expressed to produce the heavy and light chains in the patient. In some methods, the patient is monitored for level of administered antibody in the blood of the patient.
In another aspect, the invention provides methods of preventing or treating a disease associated with amyloid deposits of Axcex2 in the brain of patient. For example, the methods can be used to treat Alzheimer""s disease or Down""s syndrome or cognitive impairment. Such methods entail administering fragments of Axcex2 or analogs thereof eliciting an immunogenic response against certain epitopes within Axcex2. Some methods entail administering to a patient an effective dosage of a polypeptide comprising an N-terminal segment of at least residues 1-5 of Axcex2, the first residue of Axcex2 being the N-terminal residue of the polypeptide, wherein the polypeptide is free of a C-terminal segment of Axcex2. Some methods entail administering to a patient an effective dosage of a polypeptide comprising an N-terminal segment of Axcex2, the segment beginning at residue 1-3 of Axcex2 and ending at residues 7-11 of Axcex2. Some methods entail administering to a patient an effective dosage of an agent that induces an immunogenic response against an N-terminal segment of Axcex2, the segment beginning at residue 1-3 of Axcex2 and ending at residues 7-11 of Axcex2 without inducing an immunogenic response against an epitope within residues 12-43 of Axcex243.
In some of the above methods, the N-terminal segment of Axcex2 is linked at its C-terminus to a heterologous polypeptide. In some of the above methods, the N-terminal segment of Axcex2 is linked at its N-terminus to a heterologous polypeptide. In some of the above methods, the N-terminal segment of Axcex2 is linked at its N and C termini to first and second heterologous polypeptides. In some of the above methods, the N-terminal segment of Axcex2 is linked at its N terminus to a heterologous polypeptide, and at its C-terminus to at least one additional copy of the N-terminal segment. In some of the above methods, the heterologous polypeptide and thereby a B-cell response against the N-terminal segment. In some of the above methods, the polypeptide further comprises at least one additional copy of the N-terminal segment. In some of the above methods, the polypeptide comprises from N-terminus to C-terminus, the N-terminal segment of Axcex2, a plurality of additional copies of the N-terminal segment, and the heterologous amino acid segment. In some of the above methods, the N-terminal segment consists of Axcex21-7. In some of the above methods, the N-terminal segment consists of Axcex23-7.
In some methods, the fragment is free of at least the 5 C-terminal amino acids in Axcex243. In some methods, the fragment comprises up to 10 contiguous amino acids from Axcex2. Fragments are typically administered at greater than 10 micrograms per dose per patient.
In some methods, the fragment is administered with an adjuvant that enhances the immune response to the Axcex2 peptide. The adjuvant and fragment can be administered in either order or together as a composition. The adjuvant can be, for example, aluminum hydroxide, aluminum phosphate, MPL(trademark), QS-21 (Stimulon(trademark)) or incomplete Freund""s adjuvant.
The invention further provides pharmaceutical compositions comprising fragments of Axcex2 or other agents eliciting immunogenic response to the same epitopes of Axcex2, such as described above, and an adjuvant. The invention also provides pharmaceutical compositions comprising any of the antibodies described above and a pharmaceutically acceptable carrier.
In another aspect, the invention provides methods of screening an antibody for activity in treating a disease associated with deposits of Axcex2 in the brain of a patient (e.g., Alzheimer""s disease). Such methods entail contacting the antibody with a polypeptide comprising at least five contiguous amino acids of an N-terminal segment of Axcex2 beginning at a residue between 1 and 3 of Axcex2, the polypeptide being free of a C-terminal segment of Axcex2. One then determines whether the antibody specifically binds to the polypeptide, specific binding providing an indication that the antibody has activity in treating the disease.
In another aspect, the invention provides methods of screening an antibody for activity in clearing an antigen-associated biological entity. Such methods entail combining the antigen-associated biological entity and the antibody and phagocytic cells bearing Fc receptors in a medium. The amount of the antigen-associated biological entity remaining in the medium is then monitored. A reduction in the amount of the antigen-associated biological entity indicates the antibody has clearing activity against the antigen-associated biological entity. The antigen can be provided as a tissue sample or in isolated form. For example, the antigen can be provided as a tissue sample from the brain of an Alzheimer""s disease patient or a mammal animal having Alzheimer""s pathology. Other tissue samples against which antibodies can be tested for clearing activity include cancerous tissue samples, virally infected tissue samples, tissue samples comprising inflammatory cells, nonmalignant abnormal cell growths, or tissue samples comprising an abnormal extracellular matrix.
In another aspect, the invention provides methods of detecting an amyloid deposit in a patient. Such methods entail administering to the patient an antibody that specifically binds to an epitope within amino acids 1-10 of Axcex2, and detecting presence of the antibody in the brain of the patient. In some methods, the antibody binds to an epitope within residues 4-10 of Axcex2. In some methods, the antibody is labelled with a paramagnetic label and detected by nuclear magnetic resonance tomography.
The invention further provides diagnostic kits suitable for use in the above methods. Such a kit comprises an antibody that specifically binds to an epitope with residues 1-10 of Axcex2. Some kits bear a label describing use of the antibody for in vivo diagnosis or monitoring of Alzheimer""s disease.

Passive immunization treatment of Alzheimer""s disease


A description is given of a circuit arrangement for electronic data processing which includes a writeable memory for storing data to be protected against unauthorized access, a read-only memory for storing individualizing data, a control unit for generating given control signals in dependence on a reset signal sequence to be executed by the control unit during operation of the circuit arrangement, a scrambling pattern generator for generating scrambling pattern signals by combining at least a part of the individualizing data from the read-only memory with the control signals during the execution of the reset signal sequence and for subsequently outputting these scrambling pattern signals until the execution of a next reset sequence, and a scrambling logic unit for the scrambling of address and/or data signals of the data to be stored in the writeable memory in conformity with the scrambling pattern signals supplied by the scrambling pattern generator upon storage of this data, and for the corresponding descrambling of the data signals upon reading out from the erasable memory.

The invention relates to a circuit arrangement for electronic data processing.
The abstract in English of the document JP-A-08320832 describes a non-volatile semiconductor memory with a secrecy function, for example an EPROM, an EEPROM, a mask-programmed ROM or a so-called flash memory which utilizes a microcomputer. Such a non-volatile semiconductor memory includes a scrambling unit which modifies and outputs input information if data read from a selected element of the non-volatile memory matches entered key code information. The memory includes a storage field which consists of a plurality of non-volatile storage elements which are arranged in the form of a matrix. A user writes key code information into a non-volatile storage unit and an element of a volatile memory is selected. A comparator compares the data read from the selected storage element and the key code information and outputs the comparison results. A scrambling unit outputs the input information in non-modified form if the compared data do not correspond whereas it modifies and outputs the input information if the compared data corresponds. The aim is to enable the user to select a memory address independently. The secrecy of stored information should be improved, thus enhancing the reliability. The number of persons knowing secret key code information should thus be reduced. Moreover, the control should be simplified and the costs reduced.
It is an object of the invention to provide a circuit arrangement for electronic data processing which offers increased protection against unauthorized access.
This object is achieved by a circuit arrangement for electronic data processing according to the invention which includes
a writeable memory for storing data to be protected against unauthorized access,
a read-only memory for storing individualizing data,
a control unit for generating given control signals in dependence on a reset signal sequence to be executed by the control unit during operation of the circuit arrangement,
a scrambling pattern generator for generating scrambling pattern signals by combining at least a part of the individualizing data from the read-only memory with the control signals during the execution of the reset signal sequence and for subsequently outputting these scrambling pattern signals until the execution of a next reset signal sequence,
and a scrambling logic unit for the scrambling of address and/or data signals of the data to be stored in the writeable memory in conformity with the scrambling pattern signals supplied by the scrambling pattern generator upon storage of this data, and for the corresponding descrambling of the data signals upon reading out from the erasable memory.
Memories which are used in circuit arrangements for electronic data processing and are writeable notably in the context of the operation of such a circuit arrangement customarily have a regular structure so that address and/or data signals can be entered in conformity with a given, clearly organized scheme and data signals can also be derived in such a manner from such a memory. For applications where the secrecy of such data is of utmost importance, however, such a regular structure constitutes a drawback, because it can be comparatively simply found out by non-authorized access. Therefore, in the case of security-relevant applications, for example in the field of identification, data to be protected against discovery cannot be sufficiently reliably stored in such a memory.
It could be attempted to satisfy the described security requirements by scrambling addresses and data in the writeable memory in conformity with a fixed but as secret as possible scheme. The structure of the addresses and data is thus obscured, but if a large number of similar circuit arrangements were manufactured, the scrambling chosen would be the same in all circuit arrangements. In that case it would be possible to discover such scrambling on the basis of one specimen of said circuit arrangement and such knowledge of the scrambling scheme of this one circuit arrangement could be used to gain unauthorized access or at least facilitate access to all other circuit arrangements of the same kind.
In order to eliminate such a risk also, according to the invention the scrambling pattern used is made dependent on individualized data stored in the read-only memory. This data is selected so as to be different for each individual specimen of the circuit arrangement according to the invention, thus enabling identification of a specific, individual specimen of the circuit arrangement according to the invention. A scrambling pattern thus influenced for the address and/or data signals for the writeable memory ensures that an individual, non-recurrent scrambling pattern is indeed used for each individual specimen of the circuit arrangement according to the invention. As a result, even after discovery of the scrambling pattern of one specimen of the circuit arrangement according to the invention, it will be impossible to apply such knowledge to gain access to the protected data in the writeable memory of an arbitrary other specimen of the circuit arrangement according to the invention.
In conformity with the second step according to the invention, taken in combination with the previously described first step, the scrambling utilizes control signals which are generated by a control unit in the circuit arrangement if a predetermined reset signal sequence is to be executed during its operation. In the scrambling pattern generator the control signals generated during such a reset signal sequence (also referred to as reset sequence) are combined with the individualizing data from the read-only memory, with a part of such data or with a combination of at least a part of such individualizing data and other data, so that the scrambling pattern generated according to the invention (represented by the scrambling pattern signals) has been influenced by the individualizing data as well as by the control signals. The effect of the control signals is such that in the case of unauthorized access, causing a disturbance of the control signals, a false scrambling pattern would be generated; the use of such a false scrambling pattern would render data derived from the writeable memory useless. It can thus be prevented that in the case of unauthorized access, also referred to as a security attack, the security mechanisms of the circuit arrangement according to the invention, intended to protect the stored data, are circumvented by external influencing of given control signals, and notably that data to be protected is read from the writeable memory and hence discovered.
The circuit arrangement according to the invention can be used particularly for identification devices, notably chip cards, electronic labels, electronic access keys and the like. Not only customary data such as, for example account balances or the like, can thus be safely stored in the writeable memory; in a preferred application an EEPROM is provided as the writeable memory in which complete application programs can be stored as the data to be protected. This enables, for example a chip card provided with such a circuit arrangement to be prepared for different applications, if desired without modification of the structure. Depending on the data or programs stored in the writeable memory, such a chip card can then serve, as desired, as a credit card, an access key, purchasing identification or the like and, for example, for its function as credit card applications can be programmed as desired for different credit institutes in different locations. A combination of such specific applications, that is to say a combination individually composed for the relevant user, is also feasible. The read-only memory then provides the storage of the data individually related to the individual user. The read-only memory is preferably constructed as a programmable ROM.
In order to enable the processing of the data derived from the writeable memory and scrambled according to the invention, for example, in an arithmetic unit which is preferably of an identical construction for all specimens of the circuit arrangement according to the invention, the individually scrambled data must be reconverted into a uniform data format again upon reading out from the writeable memory, i.e. the scrambling must be suitably canceled. This operation will be referred to as xe2x80x9cdescramblingxe2x80x9d hereinafter.
The scrambling logic unit of the circuit arrangement according to the invention preferably includes a permutation stage for the permutation of bits of different value in the address and/or data signals applied to the scrambling logic unit, and also an inverter stage for inverting the values of the bits of the address and/or data signals. Thus, permutation as well as inversion of the data and/or the addresses in the writeable memory can be performed as scrambling operations. Thus, the spatial assignment of individual storage cells of the writeable memory is irregularly scrambled and the meaning of the values stored in such storage cells is obscured by irregular inversion. The permutation stage and the inverter stage are both controlled by the scrambling pattern signals.
In a further embodiment of the invention such control can be performed by control signals which are derived from the scrambling pattern signals in a decoding stage. The decoding stage preferably forms part of the scrambling logic unit.
The scrambling pattern generator in a further embodiment of the circuit arrangement according to the invention includes a clocked, retrocoupled shift register arrangement. During the reset signal sequence the shift register arrangement is supplied with the control signals and/or with at least a part of the individualizing data from the read-only memory and/or with a signal pattern derived therefrom by logic combination. On the basis of this signal pattern the shift register arrangement generates the scrambling pattern signals and stores these signals for subsequent supply to the scrambling logic unit.

Circuit arrangement for electronic data processing

Abstract: This circuit arrangement offers increased protection against unauthorized access.


An assembly structure of a cooling air supplying duct for use in a refrigerator having cantilever shelves includes a shelf supporting rail having a front wall in which a plurality of engagement slots are formed, and a cooling air discharging duct. The cooling air discharging duct is provided with an engaging opening formed in a portion thereof and a front wall in which a plurality of cooling air discharging holes for discharging cooling air to an interior of the refrigerator are formed. The shelf supporting rail is vertically fixed on an inner wall of the refrigerator and is combined with the cooling air discharging duct by being inserted into the engaging opening.

As illustrated in FIGS. 1A and 1B, an interior of the refrigerator is divided into a freezing compartment 10 and a refrigerating compartment 30 by means of a barrier 20 that is filled with an insulating material. An evaporator 12, through which a coolant of low temperature and low pressure passes, is mounted in an interior of a heat exchange chamber 11 that is disposed in a rear portion of the freezing compartment 10. A fan 14 is provided over the evaporator 12 so as to forcibly send cooling air, which is generated by the evaporator 12, to the freezing compartment 10 and the refrigerating compartment 30.
Formed in the barrier 20 are a cooling air supplying passage 22, through which the cooling air generated by the evaporator 12 in the heat exchange chamber 11 is supplied to the refrigerating compartment 30, and an air returning passage 24, through which air warmed while being circulated in the refrigerating compartment 30 is returned toward the evaporator 12.
Further, the lower end of the cooling air supplying passage 22 formed in the barrier 20 is connected to a cooling air discharging unit 32. The cooling air discharging unit 32 is widely formed in a ceiling of the refrigerating compartment 30 and serves to discharge the cooling air supplied therein to an interior of the refrigerating compartment 30.
As shown in FIG. 1B, a plurality of shelf supporting rails 38a, each having a plurality of engagement slots 38a′, are vertically mounted on an inner wall 38 of the refrigerating compartment 30. More particularly, two are mounted on a right and left portion of the inner wall 38 of the refrigerating compartment 30 and one is mounted on a central portion of the inner wall 38. The shelf supporting rails 38a serve to support cantilever shelves 34 with hooks of support brackets (not shown) of the cantilever shelves 34 respectively inserted into and engaged with the engagement slots 38a′ thereof.
Additionally, a vegetable compartment 36 is provided in a lower portion of the refrigerating compartment 30, and a machine room M, in which a compressor 40 is mounted, is formed in a lower, rear portion of the refrigerator.
Hereinafter, the circulation of the cooling air in the refrigerator with the configuration as described above will be described.
One portion of the cooling air is supplied to the freezing compartment 10 by means of the fan 14, and the remaining portion of the cooling air is supplied toward the refrigerating compartment 30 by means of the fan 14. The cooling air, which is supplied toward the refrigerating compartment 30, descends down from the heat exchange chamber 11 to the cooling air discharging unit 32 formed in the ceiling of the refrigerating compartment 30 through the cooling air supplying passage 22 formed in the barrier 20. Then, the cooling air is discharged from the cooling air discharging unit 32 to be introduced into the interior of the refrigerating compartment 30, and, subsequently, is supplied to divisions partitioned by the cantilever shelves 34 and the vegetable compartment 36 over a period of time.
The refrigerator with the configuration as described above has problems as follows. The cooling air is supplied to the refrigerating compartment 30 via the cooling air discharging unit 32 formed in the ceiling of the refrigerating compartment 30. So, gradually the cooling air flows from the upper cantilever shelf 34 to the lower cantilever shelf 34 over a period of time. Therefore, the cooling air, which reaches the lowermost cantilever shelves 34, has a relatively high temperature, which hinders the interior of the refrigerating compartment 30 from being cooled uniformly. This also deteriorates a cooling speed of the refrigerating compartment 30.
To address the aforementioned problems, U.S. Pat. No. 6,347,530 entitled "COOLING AIR SUPPLYING STRUCTURE FOR A REFRIGERATOR HAVING CANTILEVER SHELVES" discloses a cooling air supplying structure, which includes a cooling air supplying duct being vertically mounted on the inner wall of the refrigerating compartment, shelf support rails having a plurality of engagement slots, at least one of the shelf supporting rails being mounted to the cooling air supplying duct, and cantilever shelves respectively supported by the shelf supporting rails.
However, the cooling air supplying structure disclosed in the aforementioned U.S. patent has a problem that it is difficult to install the cooling air supplying structure on the inner wall of the refrigerating compartment since the cooling air supplying duct has a recessed portion on its central portion for receiving one of the shelf supporting rails, and the one of the shelf supporting rails and the cooling air supplying duct have to be screw-fixed together to the inner wall of the refrigerating compartment.

Assembly structure of a cooling air supplying duct for use in a refrigerator having cantilever shelves


A PDC/PHS phone has both PDC communication function and PHS communication function. The PDC/PHS phone switches its communication mode from a PDC communication to a PHS communication which is less power consuming than the PDC communication, when its built-in battery runs down to a reference level in the course of communication with another phone. The PDC/PHS phone switches its communication mode back to the PDC communication again, when the battery is recharged enough.

The present invention relates to wireless communication devices capable of communicating through a plurality of wireless communication networks which operate under different communication protocols, and operating with different battery power consumption rates.
Various kinds of wireless communication devices are used for mobile communications. The devices include, for instance, personal digital cellular (PDC) type phones such as a cellular phone and a car phone, and personal handy phone (PHS) type devices developed as the second generation cordless phone.
The PDC phone is capable of providing communication services over a wide area because the service area of its base station (BS) is from 1.5 kilometers to several kilometers (macro cell) in radius, and is capable of providing communication services even when phone users are moving at high speeds. However, the cellular phones and the car phones consume more electric power, because a comparatively high transmission output power is required.
On the contrary, the PHS phone provides communication services over a limited area because the service area of its cell station (CS) is from 100 meters to several hundred meters (micro cell). The PHS phones consume less electric power, because a comparatively low transmission output power is required. However, the PHS phone is not capable of providing its services when phone users are moving at high speeds.
New type of cellular phones which are compatible with both the PDC phones and the PHS phones are proposed so that such phones are operable under different communication modes, that is, under the PDC communication protocol and the PHS communication protocol.
If such a cellular phone operable under both PDC protocol (PDC mode) and PHS protocol (PHS mode) is connected to the PDC communication network and operates under the PDC communication protocol, it consumes more electric power because of its high transmission output power. The electric energy of a built-in battery is consumed rapidly when a phone talk or a transmission of a large amount of data continues for a long period of time. The remaining capacity of the battery decreases quickly, occasionally resulting in that the talk or data transmission is disabled unexpectedly.
It is therefore an object of the present invention to provide a wireless communication device which is capable of avoiding unexpected disablement of communication even when a remaining power of a battery decreases rapidly in the course of communication.
According to the present invention, a wireless communication device is operable with a built-in battery and in different communication modes. The wireless communication device includes a first communication part capable of communication through a first external communication network under a first communication mode, and a second communication part capable of communication through a second external communication network under a second communication mode which is less power-consuming than the first communication part. When a battery power decreases too much, an operable communication part of the wireless communication device is switched from the first communication part to the second communication part thereby to connect the second communication part to the second external communication network and disconnect the first communication part from the first external communication network, thereby reducing the power consumption of the battery.

Wireless communication device capable of saving battery power by switching communication mode


An electric parking brake device generates pressing force by pressing friction materials against a brake disc by causing a piston to move by motor operation. A control device executes: parking processing wherein the motor increases the pressing force to an initial pressing force higher than a lower-limit pressing force; and re-drive processing wherein the motor is driven and the pressing force increased at a re-drive time, which is a predetermined time after the end of execution of parking processing. During parking processing, the control device uses one among the initial pressing force and the predetermined time, in addition to a pressing force decrease characteristic corresponding to an assumed temperature set for use in calculation, as a basis to calculate the other of the initial pressing force and the predetermined time such that the pressing force becomes equal to or less than the lower-limit pressing force at the re-drive time.

Patent Literature 1 discloses an example of an electric parking brake device which adjusts, by a driving amount of a motor, a pressing force being a force to press a brake pad being an example of a friction material to a brake disc being an example of a rotating body integrally rotating with a wheel. In parking processing executed by such device, a shaft member moves in an axial direction to press the brake pad by driving of the motor. Then, the brake pad is brought into contact with the brake disc to be pressed against the same. When the pressing force reaches an initial pressing force, the driving of the motor is stopped.
Meanwhile, there is a case where the brake pad expands due to an increase in temperature. In a case where the parking processing is executed in a situation in which temperature of the brake pad is high and the brake pad is expanded, there is a case where the brake pad contracts due to a decrease in temperature of the brake pad thereafter and the pressing force decreases. Since this pressing force corresponds to a braking force applied to the wheel, the braking force applied to the wheel decreases when the pressing force decreases.
Therefore, in the device disclosed in Patent Literature 1, when a predetermined time elapses after the execution of the parking processing ends, the motor is re-driven, and it is determined whether the pressing force decreases on the basis of a changing mode of a current value with respect to the motor. When it is determined that the pressing force decreases, a current target value is increased, and the motor is continuously re-driven until the value of the current flowing to the motor reaches the current target value.


When a driver of a vehicle issues a command to stop an engine, an in-vehicle unit communicates with a portable device. When collation of ID codes of the in-vehicle unit and the portable device is OK, a collation ECU permits stopping of the engine. When the result of ID-code collation is NG, the ECU prohibits stopping of the engine. When a vehicle passenger has taken out the portable device from a vehicle compartment, once the engine of the vehicle is stopped, the engine can no longer be restarted. By prohibiting the stop of the engine based on the NG result of ID-code collation, however, it is possible to prevent a state in which the engine cannot be restarted. It is preferred to allow starting of the engine irrespective of the ID code collation, when the ECU stores an engine stall occurring previously.

In order to enhance security preventing a vehicle from being stolen, an immobilizer function is installed in a vehicle security system. In this system, an in-vehicle unit collates with a stored ID code an ID code acquired from a portable device such as a portable electronic key carried by a user by carrying out communication with the portable device, and controls locking/unlocking states of vehicle doors on the basis of a result of the collation.
More specifically, at a location in close proximity to the seat of a driver in a vehicle, a switch to be operated to start and stop an engine of the vehicle is provided. When the switch is operated to start the engine of the vehicle from a stopped state, the in-vehicle unit makes an attempt to communicate with the portable device and compares and collates the ID code acquired from the portable device with a stored ID code. When the result of the collation is OK, the in-vehicle unit outputs a start permission signal to an engine ECU. Receiving the start permission signal, the engine ECU becomes capable of controlling ignition timing and fuel injection quantity. Thus, the engine ECU is capable of starting the engine of the vehicle. When the result of the collation is NG, on the other hand, the engine of the vehicle cannot be started because no fuel and no ignition spark are supplied in the engine.
In such a system, however, the user is capable of unlocking a door, getting into the vehicle and starting the engine of the vehicle without having a portable device. It is thus possible that the degree of awareness of the portable device decreases. For this reason, it is likely that the driver is not aware of the fact that a passenger has taken out the portable device from the vehicle with the engine of the vehicle kept operated. In such a case, when the engine of the vehicle is once stopped, the engine can no longer be restarted because the portable device is not in the vehicle compartment.
In order to solve this problem, with the vehicle in a rest state and a door of the vehicle is opened and closed, for example, the in-vehicle unit makes an attempt to communicate with the portable device by using a vehicle compartment transmitter in order to verify that the portable device exists in the compartment. When the in-vehicle unit fails in the attempt to verify that the portable device exists in the compartment, the in-vehicle unit issues an alarm or warning in order to prevent the portable device from being taken out from the vehicle.
In this system, however, when a portable device is about to be taken out from a vehicle, an alarm is merely issued. Thus, it is possible that a passenger takes out the portable device mistakenly from the vehicle if the passenger is not aware of the alarm. In such a case, once the engine of the vehicle is stopped, the engine can no longer be restarted thereafter. U.S. Pat. No. 6,653,747 proposes an improvement to this problem.

Vehicle engine control system and method


A uterine fibroid treatment device providing for localized delivery of one or more treatment drugs for treating various uterine conditions including, for example, uterine fibroids, abnormal uterine bleeding, pelvic adhesions and endometriosis. Generally, the uterine treatment device comprises a physical positioning element that can be inserted, positioned and maintained in close proximity to the uterine tissue to be treated. The treatment drugs delivered to the treatment location can include various combinations of anti-proliferative agents and angiogenesis inhibitors to provide different treatments concurrently. In some embodiments, the physical element can also serve the dual purpose of delivering the treatment drugs while simultaneously cutting off blood flow to a mature fibroid to initiate hypoxic/ischemic conditions within the mature fibroid.

A variety of pathological conditions of the uterus are the result of cellular proliferation or abnormal cell division and growth of the myometrium or endometrium. Representative uterine conditions can include fibroids, abnormal uterine bleeding, pelvic adhesions, endometriosis and the like.
Uterine leiomyomas or fibroids are the most common tumor of the female reproductive tract affecting 20-25% of all women during their reproductive years. While uterine fibroids are generally non-cancerous, their presence can lead to a variety of problems including excessive uterine bleeding, pain and even infertility. Because of these possible issues, a variety of treatment options have been developed to address the presence of uterine fibroids.
One common method, and the most drastic, for eliminating uterine fibroids is the surgical removal of the uterus or hysterectomy. Generally, hysterectomies are performed on women who are beyond their child bearing years or have made the decision to forego bearing children. A hysterectomy is an invasive surgical procedure in which the uterus must be sufficiently exposed such that the attached vascular network, fallopian tubes and ligaments can be severed. In addition to eliminating a woman's ability to bear children, a hysterectomy as a truly invasive surgery has the potential for a variety of surgical consequences including complications such as, for example, blood loss, pain and discomfort, extended convalescence and potentially increased costs due to extended and further hospital care.
Uterine fibroids can form in a variety of locations along the uterus with each location providing a unique set of symptoms and effecting surrounding tissue in different ways. Regardless of location, uterine fibroids rely on the highly vascularized nature of the female reproductive system to grow and develop. As such, a variety of alternative treatment methods have been proposed in which the blood vessels connected to said uterine fibroids are accessed to provide treatment. For example, U.S. Pat. No. 6,059,766 proposes accessing vessels of the fibroid mass such that a minimally invasive catheter or probe can administer an embolyzing material. Another alternative treatment method has proposed temporary clamping of the vessels supplying a fibroid mass for a period long enough to cause fibroid cell death without permanently reducing blood flow to the myometrium and ovaries while also avoiding ischemia injury.
Finally, a variety of treatment protocols have been proposed in which the physical structure of the uterine fibroid is attacked so as result in tissue ablation and in some instances, physical removal of only the fibroid mass. For example, it has been proposed that appropriate medical imaging technologies can be utilized to deliver high intensity focused ultrasound (HIFU) energy into the fibroid mass to ablate the tissue wherein the fibroid can be resorbed within the body. In other instances, it has been proposed to introduce a cryogenic instrument capable of freezing, and thereby, killing the fibroid cells. Finally, a variety of minimally invasive instruments have been proposed to core or debulk fibroid masses wherein the material can then be removed by a suction device.
While a variety of procedures have been contemplated for treatment of uterine fibroids, there remains a need for new minimally invasive procedures that delivery effective treatment options while reducing the potential for negative treatment outcomes.

Apparatus and methods of treatment of pathologic proliferative conditions uterine tissue


A thermal printer is adapted to prevent crease formation in a dye transfer area of a dye donor web that can cause line artifacts to be printed on a dye receiver during a dye transfer from the dye transfer area to the dye receiver in a dye transfer printer.

The invention relates generally to dye transfer printers such as thermal printers, and in particular to the problem of crease or wrinkle formation in successive dye transfer areas of the donor web. Crease formation in the dye transfer area can result in an undesirable line artifact being printed on a dye receiver.
A typical multi-color dye donor web that is used in a thermal printer is substantially thin and has a repeating series of three different rectangular-shaped color sections or patches such as a yellow color section, a magenta color section and a cyan color section. Also, there may be a transparent colorless laminating section immediately after the cyan color section.
Each color section of the dye donor web consists of a dye transfer area that is used for dye transfer printing and a pair of opposite longitudinal edge areas alongside the dye transfer area which are not used for printing. The dye transfer area is about 95% of the web width and the two edge areas are each about 2.5% of the web width.
To make a multi-color image print using a thermal printer, a motorized donor take-up spool pulls the dye donor web from a donor supply spool in order to successively advance an unused single series of yellow, magenta and cyan color sections over a stationary bead of selectively heated resistive elements on a thermal print head between the two spools. Respective color dyes within the yellow, magenta and cyan color sections are successively heat-transferred via the bead of selectively heated resistive elements, in superimposed relation, onto a dye receiver such as a paper or transparency sheet or roll, to form the color image print. The bead of resistive elements extends across the entire width of a color section, i.e. across its dye transfer area and the two edge areas alongside the transfer area. However, only those resistive elements that contact the dye transfer area are selectively heated. Those resistive elements that contact the two edge areas are not heated. In other words, the dye transfer is effected from the dye transfer area to the receiver medium, but not from the two edge areas to the receiver medium.
As each color section, including its dye transfer area and the two edge areas alongside the transfer area, is advanced over the bead of selectively heated resistive elements, the color section is subjected to a longitudinal tension particularly by a pulling force of the motorized donor take-up spool. Since the dye transfer area is heated by the resistive elements, but the two edge areas alongside the transfer area are not, the transfer area is significantly weakened and vulnerable to stretching as compared to the edge areas. Consequently, the longitudinal tension will stretch the dye transfer area relative to the two edge areas. This stretching causes the dye transfer area to become thinner than the non-stretched edge areas, which in turn causes creases or wrinkles to develop in the transfer area, particularly in those regions of the transfer area that are close to the edge areas. The longitudinal creases or wrinkles are most notable in the regions of the dye transfer area that are close to the two edge areas because of the sharp, i.e. abrupt, transition between the weakened transfer area and the stronger edge areas.
As the donor web is advanced, the creases or wrinkles tend to spread or extend from a trailing or rear end portion of a used dye transfer area at least to a leading or front end portion of the next dye transfer area to be used. A problem that can result is that a crease or wrinkle in the leading or front end portion of the next dye transfer area to be used will cause an undesirable line artifact to be printed on a leading or front end portion of the dye receiver when dye transfer occurs at the crease. The line artifact printed on the dye receiver is relatively short, but quite visible.
The question presented therefore is how to solve the problem of the creases or wrinkles being created in an unused transfer area so that no line artifacts are printed on the dye receiver.
According to one aspect of the invention, there is provided a method of preventing crease formation in a dye transfer area of a dye donor web that can cause line artifacts to be printed on a dye receiver during a dye transfer from the dye transfer area to the dye receiver in a dye transfer printer. The method comprises:
heating the dye transfer area of the dye donor web sufficiently to effect a dye transfer from the dye transfer area to the dye receiver, and not heating opposite edge areas of the dye donor web alongside the dye transfer area sufficiently to effect a dye transfer from the edge areas to the dye receiver, but which therefore causes the dye transfer area to become more susceptible to being stretched than the edge areas; and
mechanically causing the edge areas to be stretched substantially the same as the dye transfer area, when the dye transfer area and edge areas are subjected to a pulling force that tends to stretch the dye transfer area and edge areas, to avoid a reduction in stretching from the dye transfer area to the edge areas that would form creases in the dye transfer area which can cause line artifacts to be printed on the receiver medium.
According to another aspect of the invention, there is provided a thermal printer capable preventing crease formation in a dye transfer area of a dye donor web that can cause line artifacts to be printed on a dye receiver during a dye transfer from the dye transfer area to the dye receiver. The thermal printer comprises:
a thermal print head adapted to heat the dye transfer area of the dye donor web sufficiently to effect a dye transfer from the dye transfer area to the dye receiver, and not heat opposite edge areas of the dye donor web alongside the dye transfer area sufficiently to effect a dye transfer from the edge areas to the dye receiver, but which therefore causes the dye transfer area to become more susceptible to being stretched than the edge areas; and
a platen roller that holds the dye transfer area and the edge areas against the thermal print head during the dye transfer from the dye transfer area to the dye receiver, and which is adapted to mechanically cause the edge areas to be stretched substantially the same as the dye transfer area, when the dye transfer area and edge areas are subjected to a pulling force that tends to stretch the dye transfer area and edge areas, to avoid a reduction in stretching from the dye transfer area to the edge areas that would form creases in the dye transfer area which can cause line artifacts to be printed on the receiver medium.

Preventing crease formation in donor web in dye transfer printer that can cause line artifact on print


An endoscopic surgical instrument is disclosed which is particularly facilitated for grasping the anvil portion of an circular surgical stapling device. The present instrument includes a generally elongated shaft, with a pair of cooperating jaw members disposed at the distal end of the shaft. The jaw members cooperate in a pincer-like action for gripping the anvil portion of the associated surgical stapler therebetween. The jaw members include cooperating jaw portions, each of which defines a semi-cylindrical gripping surface. The jaw portions are angularly disposed relative to the longitudinal axis of the associated shaft, and are otherwise configured to facilitate gripping and manipulation of the anvil portion of the surgical stapling device, as well as tissue manipulation.

Generally, surgical stapling has made substantial advances in the past decades. Specifically, in the area of internal anastomotic stapling the advances have been quite dramatic. Devices such as the Proximate.TM. ILS stapler, produced by the assignee of the present invention, Ethicon, Inc., Somerville, N.J., have enabled surgeons to perform operations and procedures which were heretofore perceived as difficult, if not impossible, with relative ease. One example of such a device is disclosed in U.S. Pat. No. 5,104,025.
In performing surgical anastomotic stapling, generally the two pieces of lumen are attached by a ring of staples. During this procedure, a circular knife blade is used to separate tissue which is held within the circular ring. The circular ring is then removed with the stapler so that a circular opening within the lumen is completed along the surgical stapling line.
In performing these surgical procedures it is often necessary to separate the anvil portion on which the staples are clinched from the stapling portion from which the staples are expelled. The end of one of the lumens is attached to the shaft of the anvil portion for example by a purse string suture, and the end of the other lumen is attached to the stapling portion such as by another purse string suture, or other technique. It is then necessary to grasp and hold the anvil shaft to reattach the anvil portion to the stapling portion.
It has heretofore been the practice to use instruments not particularly suited or configured to grasp and hold the anvil shaft, such as conventional forceps that include jaw portions to grasp the anvil shaft. It has recently been proposed to utilize special forceps that include jaw portions that are configured to grasp and hold the anvil shaft. The jaw portions include semi-cylindrical grasping surfaces to contact the outer surface of the anvil shaft. The grasping surfaces are smooth to maximize the surface area in contact with the anvil shaft. The heretofore used forceps are not intended to be inserted into an anatomical cavity through a trocar cannula.
There is a need for a surgical instrument for grasping and holding an anvil shaft of an internal, circular surgical stapling device that is extendable through a trocar cannula. It is necessary that such a device securely grasp the anvil shaft and be able to manipulate the anvil portion when extended deep into the pelvis area or other surgical region.


Disclosed is a shaped article comprising a continuous oriented polymer matrix having dispersed therein microbeads of a polymer which are at least partially boredered by void space, the microbeads being present in an amount of about 5-50% by weight based on the weight of said oriented polymer, said void space occupying about 2-60% by volume of said shaped article. Preferably, the microbeads are cross-linked to an extent they will be resilient and elastic at the orientation temperature, and are coated with a slip agent. The shaped article is preferably in the form of a sheet, fibers, or other molded article, preferably has a relatively low specific gravity and whiteness.

Blends of linear polyesters with other incompatible materials of organic or inorganic nature to form microvoided structures are well-known in the art. U.S. Pat. No. 3,154,461 discloses, for example, linear polyesters blended with, for example, calcium carbonate. U.S. Pat. No. 3,944,699 discloses blends of linear polyesters with 3 to 27% of organic material such as ethylene or propylene polymer. U.S. Pat. No. 3,640,944 also discloses the use of poly(ethylene terephthalate) blended with 8% organic material such as polysulfone or poly(4-methyl-1-pentene). U.S. Pat. No. 4,377,616 discloses a blend of polypropylene to serve as the matrix with a small percentage of another and incompatible organic material, nylon, to initiate microvoiding in the polypropylene matrix. U.K. Patent Specification No. 1,563,591 discloses linear polyester polymers for making opaque thermoplastic film support in which have been blended finely divided particles of barium sulfate together with a void-promoting polyolefin, such as polyethylene, polypropylene or poly-4-methyl-1-pentene.
The above-mentioned patents show that it is known to use incompatible blends to form films having paper-like characteristics after such blends have been extruded into films and the films have been quenched, biaxially oriented and heat set. The minor component of the blend, due to its incompatibility with the major component of the blend, upon melt extrusion into film forms generally spherical particles each of which initiates a microvoid in the resulting matrix formed by the major component. The melting points of the void initiating particles, in the use of organic materials, should be above the glass transition temperature of the major component of the blend and particularly at the temperature of biaxial orientation.
As indicated in U.S. Pat. No. 4,377,616, spherical particles initiate voids of unusual regularity and orientation in a stratified relationship throughout the matrix material after biaxial orientation of the extruded film. Each void tends to be of like shape, not necessarily of like size since the size depends upon the size of the particle.
Ideally, each void assumes a shape defined by two opposed and edge contacting concave disks. In other words, the voids tend to have a lens-like or biconvex shape. The voids are oriented so that the two major dimensions are aligned in correspondence with the direction of orientation of the film structure. One major dimension is aligned with machine direction orientation, a second major dimension is aligned with the transverse direction orientation, and a minor dimension approximately corresponds to the cross-section dimension of the void-initiating particle.
The voids generally tend to be closed cells, and thus there is virtually no path open from one side of a biaxially oriented film to the other side through which liquid or gas can traverse. The term "void" is used herein to mean devoid of solid matter, although it is likely the "voids" contain a gas.
Upon biaxial orientation of the resulting extruded film, the film becomes white and opaque, the opacity resulting from light being scattered from the walls of the microvoids. The transmission of light through the film becomes lessened with increased number and with increased size of the microvoids relative to the size of a particle within each microvoid.
Also, upon biaxial orientation, a matte finish on the surface of the film results, as discussed in U.S. Pat. No. 3,154,461. The particles adjacent the surfaces of the film tend to be incompressible and thus form projections without rupturing the surface. Such matte finishes enable the film to be written upon with pencil or with inks, crayons, and the like.
U.S. Pat. No. 3,944,699 also indicates that the extrusion, quenching and stretching of the film may be effected by any process which is known in the art for producing oriented film, such as by a flat film process or a bubble or tubular process. The flat film process involves extruding the blend through a slit dye and rapidly quenching the extruded web upon a chilled casting drum so that the polyester component of the film is quenched into the amorphous state. The quenched film is then biaxially oriented by stretching in mutually perpendicular directions at a temperature above the glass transition temperature of the polyester. The film may be stretched in one direction and then in a second direction or may be simultaneously stretched in both directions. After the film has been stretched it is heat set by heating to a temperature sufficient to crystallize the polyester while restraining the film against retraction in both directions of stretching.
Paper is essentially a non-woven sheet of more or less randomly arrayed fibers. The key properties of these structures are opacity, texture, strength, and stability. Natural polymers are generally weaker and less stable. A serious problem, for example, is brightness reversion or fading of papers and fibers.
Although there are many ways to produce opaque media, this invention is concerned with creating opacity by stretching or orienting plastic materials to induce microvoids which scatter light, preferably white and ultraviolet light. A large body of prior art deals with this technique, wherein a plurality of inorganic solid particles are used as the dispersed phase, around which the microvoids form. Some significant problems associated with this approach are: (1) agglomeration and particle size control, (2) abrasive wear of extrusion equipment, guides, and cutters, (3) high specific gravity of these solids, (4) poor void nucleation around the solid particles due to the low thermal contraction of solids relative to liquids and polymer wetting and adhesion to the solid surfaces, (5) cost of these materials on a volume basis, and (6) handling and processing problems in general.
Of particular interest is U.S. Pat. No. 4,770,931 which is directed to articles comprising a continuous polyester phase having dispersed therein microbeads of cellulose acetate which are at least partially bordered by void space. The present invention is unexpected, however, in that while the geometries are similar, the cross-linked beads disclosed herein cavitate more efficiently generating higher void fractions and improved properties per weight of added beads. Also, the compositions of this invention have superior thermal and chemical stability, when compared with the prior art, especially the cellulose esters. Also, of particular interest is U.S. Pat. No. 4,320,207 which discloses oriented polyester film containing pulverized cross-linked polymers

Shaped articles from orientable polymers and polymer microbeads


The electromagnetic vibration exciter system with an adjustable electro-viscoelastic suspension device comprises an electromagnetic vibration exciter, a power amplifier and an adjustable electro-viscoelastic suspension device, which acts as the suspension device of the electromagnetic vibration exciter. The adjustable electro-viscoelastic suspension device contains a displacement sensor detecting the displacement of the moving component, a first adjustable amplifier and a second adjustable amplifier, a differentiator, an adjustable phase shifter, an adder and a proportioner. The linearity of the stiffness and damping of the exciter system is excellent, which can be adjusted as need through the adjustment of gain of the adjustable amplifier, the proportioner, the adjustable phase shifter. This invention has adjustable and linear parameters and it is also easy to be realized.

The electromagnetic vibration exciter usually comprises a fixed base, a magnetic circuit, a moving component, a guiding device, a suspension system and so on. With the development of the science and technology, the electromagnetic exciters are constantly required to output a vibration signal with a larger and larger displacement amplitude. For example, at a low frequency or even an ultralow frequency, the exciter should output a vibration signal with the displacement amplitude of 1000 mm in order to obtain a large signal-to-noise ratio. The long-stroke vibration exciter raises new requirement for the property of the elastic suspension device.
An electromagnetic vibration exciter generally uses mechanical elastic suspension devices, such as metal spring leaf or rubber tubes, etc. to support and restore the moving component. When the operating stroke of the exciter is relatively small, the mechanical elastic suspension device operates in a linear zone, whose effect on the accuracy of the output waveform of the exciter is negligible. When the operating stroke of the exciter is relatively large (for example, when working at an ultralow frequency up to 0.01 Hz, the exciter could output a vibration signal with the displacement amplitude of up to 1000 mm), the mechanical elastic suspension device will exhibit relatively large nonlinear characteristics, which will have a relatively large impact on the exciter performance. Besides, the larger the displacement amplitude of the exciter is, the smaller the stiffness of the mechanical elastic suspension device should be. However, in order to reduce the effect of the zero drift of the moving component and the environmental noise, the dampness of the suspension device should be relatively large. It is difficult to design such type of mechanical elastic suspension device with small stiffness and large dampness. In addition, due to that the material characteristics of the mechanical elastic suspension device change always with time, the positional accuracy cannot be repeatable. Finally, when the installation of the mechanical elastic suspension device is finished, its stiffness and damping parameters cannot be modified freely any more. For these reasons, the mechanical elastic suspension device cannot meet the requirement arisen with the continuous development of electromagnetic exciters, especially for the long-stroke electromagnetic exciter.

Electromagnetic vibration exciter system with adjustable electro-viscoelastic suspension device

NATIONAL INSTITUTE OF METROLOGY P.R. CHINA


An image processing apparatus for adjusting the luminance of a target pixel of an image is provided. The target pixel includes original pixel data and corresponds to a mask value. The image processing apparatus includes a luminance detection unit, a luminance compensation unit and a mapping unit. The luminance detection unit generates an original luminance value according to the original pixel data. The luminance compensation unit adjusts the original luminance value according to a non-linear function to generate a compensated luminance value. The mapping unit generates adjusted pixel data according to the compensated luminance value. The non-linear function at least includes a first monomial function, which has a base part associated with an inverse value of the original luminance value and an exponent part associated with the mask value.

1. Field of the Invention
The invention relates in general to an image processing apparatus and an image processing method using the same, and more particularly to an image processing apparatus for regional image enhancement and an image processing method using the same.
2. Description of the Related Art
Current image enhancement technologies are divided into two categories—global image enhancement and regional image enhancement. The former directly adjusts the luminance of an entire image, whereas the latter determines an enhancement level of a region of an image according to the corresponding regional luminance of the image. Compared to global image enhancement, regional image enhancement in general yields better image quality, and the contrast of individual regions of the image processed by regional image enhancement is also higher.
However, regional image enhancement requires a larger computation amount and also has higher hardware costs. Therefore, there is a need for an image processing technology that effectively reduces the computation amount and lowers hardware costs for regional image enhancement.

Image processing apparatus for regional image enhancement and image processing method using the same


Approaches for processing captured image to detect facial portion of a user within the captured image are described. In an example, a facial image from the processed captured image may be derived. Based on the derived facial image, determining a set of specular features and texture-based feature vector. Based on the specular features and the texture-based feature vector, whether the facial image is of a facial substitute or not may be ascertained.

Access to computing devices may be permitted on the basis of an authentication mechanism. Modern devices have now begun utilizing facial recognition as one such authentication mechanisms. In such a case, the computing device may be positioned with respect to the face of the authorized individual. Based on the identification of the user, access to the computing device may be permitted. In certain cases, individuals other than the authorized users may seek to circumvent such authentication mechanisms by using an image, such as physical photograph, electronic image, etc., of the authorized user to spoof the device into permitting access. Hence it is important for authentication systems to distinguish between the actual user and one pretending to be the user. To such an end, appropriate authentication measures need to be implemented to prevent spoofing.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings


A method for detecting memory cells that are stuck in a physical state. The method includes performing a diagnostic read of a memory cell in a memory system. The memory system is configured to utilize at least one read threshold value to determine a read data value stored in the memory cell when performing a data read operation on the memory cell. Performing the diagnostic read includes: comparing a measurement property of the memory cell to at least one diagnostic threshold value, where at least one of the diagnostic threshold values is different from all of the read threshold values; and identifying the memory cell as being stuck in a physical state based on the comparing. Based on identifying the memory cell as being stuck in a physical state, an indication that memory cell is stuck is output along with a diagnostic data value associated with the physical state.

The present invention relates generally to computer memory, and more specifically, to the detection of memory cells that are stuck in a physical state.
In some memory technologies, a common failure mechanism for a memory cell is for the memory cell to experience a change in its capability to convert to a desired state, typically as a result of too many write attempts. For example, in phase change memory (PCM) it has been documented that after a certain number of write attempts, a memory cell may either fail to "reset" fully or it may become stuck in a very high resistance state as a result of the cell effectively becoming detached from its electrode. In the case of a binary PCM, memory cells experiencing these phenomena may be perceived as "stuck-at set" or "stuck-at reset." In the case of a multilevel PCM, failing to reset fully may manifest as an inability to reach the higher resistance levels, while being stuck in a very high resistance level may manifest as being stuck in the level with highest resistance.

Detection of memory cells that are stuck in a physical state

International Business Machines Corporation


A flexible, waterproof, lightweight compact cover for the top of a golf bag and for golf clubs having a first end and a second end. The first end is snugly secured about the top of the golf bag with fasteners. The first end has at least one slit therein which is received by a ring on the top of the bag preventing rotation of the cover circumferentially about the top of the bag. The second end of the bag extends outwardly from the bag covering the golf clubs and the top of the golf bag. The second end of the cover is folded back and fastened to the first end of the cover. To gain access to the golf club, the second end of the cover is lifted and the golfer may reach in to remove the golf club while still preventing rain from entering the top of the golf bag. The second end of the cover may be rolled downwardly to form a collar about the top of the golf bag and, when so disposed, the cover may be unrolled rapidly to protect the top of the golf bag and golf clubs from rain and inclement weather.

Covers are known for golf bags to protect the inside of the bag and the golf clubs in the bag from rain and other inclement weather.
In U.S. Pat. No. 2,718,251 issued to Barbato, there is disclosed a cover for completely enclosing a golf bag and including an end portion for enclosing the heads of golf clubs contained in the golf bag. The upper end of the cover has a zipper closure for removal of the golf clubs.
U.S. Pat. No. 2,985,212 issued to Dozier discloses a cover which is adapted to fit over and substantially envelop the entire golf bag and the golf clubs continued therein. There is a slit across the top of the bag with a flap overlapping the slit.
Another rain cover for a golf bag mounted to a pull golf cart is disclosed in U.S. Pat. No. 4,474,388 issued to Wagner. This cover extends as side portions on two opposite sides of the bag and has a top roof portion slanting across the top of the bag.
Still another rain cover is disclosed and U.S. Pat. No. 3,754,517 issued to Rainieri. The cover is a tube which preferably is of sufficient length to fully cover the golf bag. A flap over the top of the golf bag is an extension of one wall of the cover which is folded over the opposite wall and a heat seal is formed across the overlapping sheets.
U.S. Pat. No. 3,977,451 issued to Duba discloses a cover which can be used with a golf bag having a hood to cover the opening provided in the hood of bag.
Additional prior art patents known to the applicant are as follows:
______________________________________ Inventor U.S. Pat. No. ______________________________________ Brown 2,747,637 Davis 3,288,189 Finderson D 238,086. ______________________________________
Despite these disclosures in the prior art, there is still a need for a simple, easily installed, easy to use device to protect the top of a golf bag and the golf clubs from the rain and inclement weather.


A disk drive with a substantially spaced apart pivot configuration employing Knife Edge type pivot technology, or more specifically, at least one but preferably two contact points with relative movement of pin/cup structures with sliding and/or roll-off motion at contact point forming an axis of rotation and/or with inherently limited rotational range with rotatable confinement of movement along the pivot axis also contributing to either elimination and/or improvement of conventional elements/structures of the disk drive.

The present invention relates primarily to head transducer moving storage devices which, besides "Winchester" type devices, also include similar applications such as floppy disk which may also utilize the Bernoulli concept. The head transducer may be magnetic and/or optical in nature. If optical, the transducer may include invisible wavelength transducing or similar means, but is not limited thereto. The transducer interface may include a substantially fixed distance through the use of flying, viscous and/or contact means.
A large amount of disclosure relating to this invention particularly regarding the pivot technology including inherent partial rotation YAW-AXIS means is referred to in U.S. Pat. No. 4,995,025 Schulze.
Besides a customary spindle as a full turn mover, typically full-turn ball bearings are also used for linear slides and/or rotary pivot means suspending one or more heads and partial turn mover means like voice coils or magnets. Besides being costly, full turn ball bearing pivots also exhibit an undesirable amount of non-repeatable friction.
Ball bearing pivots also require tight tolerances for the interfacing parts. The seating, run-out and evenly distributed preload of the races are of great significance in order to assure proper servo-operation. Essentially two full turn ball bearings with several individual balls are required.
Each ball has at least two contact surfaces and even more when the balls either touch each other or a spacer cage.
In a certain scenario including droppage of a unit, two balls may encounter almost all of the Hertzian or surface stress on at least two convex surfaces, one being the ball and the other the circumference of the inner race, establishing unfavorable stress conditions and also allowing only relatively low stiffness.
The instant invention, by contrast, has substantially at least one but typically two contact areas for each of the two individual pin/cup means if sliding for repeatability is employed.
A convex and a concave interface, but not limited thereto, for lowering of surface tensions or stresses is utilized.
Optionally, the contact areas may be elongated in a direction along the pivot axis.
For typically round recording features like in Optical Recording with only a requirement for having to repeat perhaps a center position, only substantially one contact point per individual pin structure may be required. This rolling motion may also potentially yield the lowest amount of friction. In the abovementioned sliding motion with highest position repeatability requirements due to the elongate shape and accordingly tight skew requirements of the recording features, only typically two contact points/lines with only minute friction torque radii may generate perhaps a slightly higher amount of friction compared to rolling motion. In the context of this invention, these two contact points/lines per individual pin/cup shall be termed as one contact point. However, for full turn ball bearings, several balls are being used. First, the balls generate a sliding friction torque about their own radii when perhaps most contact each other or a spacer cage. Second, additional friction torque is generated by a much larger radius from the center of the bearing to the center of the individual balls including rolling motion and translated sliding motion. Besides other aspects, the friction torque for full turn ball bearings is typically higher. Depending on preload alignment of those ball bearings and/or head pair preload difference, the individual balls may aggregate on one side and generate a torque of a magnitude which voice coils particularly of smaller drives could not overcome. Especially here, distinction is also made between static and dynamic friction. In perspective, radii for the instant invention could progress down to about a thousands of an inch, but not limited thereto, while such functional radii for full turn ball bearings could be about several orders of magnitude higher. It is also shown that contactless magnetic preloading is very repeatable and can also accommodate for bias torques if needed. In ball bearings, by contrast, the balls can move around versus their original position and may or may not make contact in certain circumstances including reversal of direction besides others, generating non-repeatable friction. A high amount of friction also increases the dead-band. In the presence of an undesirably large dead-band, a higher amount of voice coil power has to be applied to overcome such friction before movement of the arm structure can occur. A low dead-band facilitates higher precision of the servo-operation.
The state of the art with full turn ball bearing pivots employs plane versus projected sheet-metal of the instant invention and also has a pivot housing as an integral portion of the deck means. However, such integral portion does not provide ferro-magnetic loop means as the instant invention may provide.


A low-power non-contact proximity sensor with improved sensitivity. In particular, the non-contact proximity sensor includes a capacitive sensor decoupled from a surrounding environment by a guard ring. Both the capacitive sensor and the guard ring are driven by a direct current (DC) power source, with the guard ring driven based on feedback from the voltage applied to the capacitive sensor.

Capacitive proximity sensors are widely used in various applications and are generally known. Systems using capacitive proximity sensors typically measure the capacitance (or change in capacitance) of a sensing electrode as an object being sensed moves in relation to the electrode. Typically, the sensing electrode is connected to an alternating current (AC) or radio frequency (RF) source and the current to the electrode is monitored to detect capacitance changes. Capacitive sensors typically signal movement of an object by controlling the output frequency of an oscillator.


Apparatus is provided that can be delivered through a catheter to a remote location in a patient's body. The apparatus may include a first structure that can be positioned in all dimensions in a controlled manner and stabilized in that desired position, a second structure that can then position a lumen axis at a desired angle relative to the first structure, and a third member that can pass through the lumen and approach and engage with force (e.g., penetrate) a desired location on the anatomy without compromising maintaining the desired position. The apparatus effectively separates the forces needed for positioning and the forces needed for tissue engagement (e.g., penetration).

This invention relates to medical procedures and apparatus, and more particularly to medical procedures and apparatus that employ catheters to reach remote locations in a patient's body.
Certain catheter-based medical procedures may benefit from first establishing reference point apparatus at a remote location in the patient's body. Then an actual procedure can be performed in relation to the reference point apparatus. Examples of what is being referred to are procedures that involve crossing the atrial septum by piercing the septum from the right atrium to the left atrium such as in an ablation procedure, closing a patent foramen ovale ("PFO"), and any other left atrial procedure. If this could be done starting from stable and secure reference apparatus already in place at a desired location in the right atrium, the penetration of the septum could be made more precise, safer, and easier. It is therefore an object of this invention to provide such reference apparatus that can be delivered and deployed via a catheter, and which then provides a stable and secure "platform" from which one or more further procedures can be carried out.

Remote body tissue engaging methods and apparatus

St. Jude Medical, Cardiology Division, Inc.


The present invention comprehends a plurality of embodiments of a hydraulic control system for various configurations of dual clutch transmissions. The hydraulic control systems all include a regulated source of pressurized hydraulic fluid including an electric pump, a filter and an accumulator, a pair of pressure control valves and a branching hydraulic circuit including pressure or flow control valves, spool or logic valves and two position valves which collectively supply and exhaust hydraulic fluid from a plurality of shift actuators. The actuators are connected to shift rails which include shift forks and are slidable to engage synchronizers and positive clutches associated with the various gear ratios.

The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
In automotive transmission art, the dual clutch transmission (DCT) is a relatively new concept. A typical dual clutch transmission configuration includes a pair of mutually exclusively operating input clutches which drive a pair of input shafts. The input shafts may be disposed on opposite sides of an output shaft or may be disposed concentrically between spaced-apart output shafts. One of each of a plurality of pairs of constantly meshing gears which provide the various forward and reverse gear ratios is freely rotatably disposed on one of the shafts and the other of each pair of gears is coupled to one of the other shafts. A plurality of synchronizer clutches selectively couple the freely rotatable gears to the associated shaft to achieve forward and reverse gear ratios. After the synchronizer clutch is engaged, the input clutch associated with the input shaft having the engaged synchronizer clutch is applied to transmit power through the transmission. Reverse gear is similarly achieved except that it includes an additional (idler) gear to provide torque reversal.
Dual clutch transmissions are known for their sporty, performance oriented operating characteristics which mimic those of a conventional mechanical (manual) transmission. They also typically exhibit good fuel economy due to their good gear mesh efficiency, ratio selection flexibility, reduced clutch losses and the lack of a torque converter.
There are, however, design considerations unique to dual clutch transmissions. For example, because of heat generated during clutch slip, the input clutches must be of relatively large size. Furthermore, such heat generation typically requires correspondingly larger and more complex cooling components capable of dissipating relatively large quantities of heat. Finally, because such transmissions typically have many sets of axially aligned, meshing gears, their overall length may limit their use to certain vehicle designs.
Control of the input clutches and selection and engagement of a particular gear by translation of a synchronizer and associated positive clutch is typically achieved by a hydraulic control system. Such a system, itself under the control of an electronic transmission control module (TCM), includes hydraulic valves and actuators which engage the synchronizers and gear clutches. Optimum operating efficiency and thus fuel efficiency and minimal heat generation can be achieved by designing such hydraulic control systems to exhibit low leakage and positive control characteristics. The present invention is so directed.

Hydraulic control systems for dual clutch transmissions


Methods and apparatus disclosed herein enable a half-duplex, HD, wireless communication device, WCD (16), to remain synchronized to a supporting communication network (10), during uplink transmissions that use a large repetition factor, also referred to a using a large bundle size. For example, the WCD (16) uses a rule whereby the WCD (16) tunes back to the downlink carrier from time to time while making an uplink transmission that uses a large repetition factor. Re-tuning to the downlink carrier from time to time in this manner allows the WCD (16) to correct and maintain its time and frequency synchronization with respect to the network (10).

Cellular communication systems are currently being developed and improved for machine type communications (MTC). MTC is characterized by lower demands on data rates than for example mobile broadband, but generally has more stringent requirements regarding cost, service coverage, power. For example, a MTC device may be intended to operate for years on batteries, without charging or replacing the batteries.
Currently, the Third Generation Partnership Project (3GPP) is standardizing Enhanced Machine-Type Communications (eMTC) as well as Narrowband Internet of Things (NB-IoT) as part of LTE Release 13 for satisfying all the requirements put forward by MTC type applications, while maintaining backward compatibility with the current LTE radio access technology. See RP-150492 (3GPP TSG RAN Meeting #67, Shanghai, China, 9-12 Mar. 2015) regarding eMTC, and see RP-152284 (3GPP TSG RAN Meeting #70, Sitges, Spain, Dec. 7-10, 2015) regarding NB-IoT.
The eMTC features specified in RP-152024 and in R1-157926 (3GPP TSG RAN Meeting #70, Sitges, Spain, Dec. 7-10, 2015) include a low-complexity User Equipment (UE) category called UE category M1 (or Cat-M1 for short) and Coverage Enhancement (CE) techniques involving CE modes A and B that can be used together with UE category M1 or any other LTE UE category.
All eMTC features (both Cat-M1 and CE modes A and B) operate using a reduced maximum channel bandwidth compared to normal LTE. The maximum channel bandwidth in eMTC is 1.4 MHz, whereas it is up to 20 MHz in normal LTE. The eMTC UEs are still able to operate within the larger LTE system bandwidth without problem. The main difference compared to normal LTE UEs is that the eMTCs can only be scheduled with 6 Physical Resource Blocks (PRBs), 180 kHz at a time.
In CE modes A and B, the coverage of physical channels is enhanced through various coverage enhancement techniques, the most important being repetition or retransmission. In its simplest form, this means that the 1-ms subframe to be transmitted is repeated a number of times, e.g., just a few times if a small coverage enhancement is needed or hundreds or thousands of times if a large coverage enhancement is needed.
The objective of NB-IoT is to specify a radio access for cellular IoT, based to a great extent on a non-backward-compatible variant of E-UTRA, that addresses improved indoor coverage, support for massive number of low throughput devices, low delay sensitivity, ultra-low device cost, low device power consumption and (optimized) network architecture. Here, "E-UTRA" denotes "Evolved UMTS Terrestrial Radio Access" and "UMTS" denotes the "Universal Mobile Telecommunications Service."
The NB-IoT carrier bandwidth is 200 KHz, and examples of operating bandwidth for LTE are 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, etc. NB-IoT supports three different modes of operation. A first mode, "Stand-alone operation," uses for example the spectrum currently being used by GSM Edge Radio Access Network (GERAN) systems as a replacement of one or more GSM carriers, where "GSM" denotes the "Global System for Mobile Communications." In principle, NB-IoT operates on any carrier frequency which is neither within the carrier of another system and not within the guard band of another system's operating carrier. The other system can be another NB-IoT system or a system associated with another Radio Access Technology (RAT), such as a LTE system. A second mode, "Guard band operation," uses the unused resource blocks within a LTE carrier's guard band. The term "guard band mode" may be used interchangeably with the term "guard bandwidth." As an example, in case of LTE BW of 20 MHz (100 Resource Blocks or RBs), the guard band operation of NB-IoT can be placed anywhere outside the central 18 MHz but within 20 MHz LTE BW.
A third, mode contemplated for NB-IoT, referred to as "In-band operation," uses resource blocks within a normal LTE carrier. The in-band operation mode may also be referred to as in-bandwidth operation. Broadly, the operation of one RAT within the BW of another RAT is referred to as in-band operation. As an example, in a LTE BW of 50 RBs (50 RBs), NB-IoT operation over one resource block (RB) within the 50 RBs is called in-band operation.
In NB-IoT, the downlink transmission is based on OFDM with 15 kHz subcarrier spacing for all the scenarios: standalone, guard-band, and in-band. For UL transmission, both multi-tone transmissions based on SC-FDMA, and single tone transmission is supported. This means that the physical waveforms for NB-IoT in the downlink and also partly in the uplink are similar to those seen in LTE.
In the downlink design, NB-IoT supports both master information broadcast and system information broadcast, of which broadcasts are carried by different physical channels. For in-band operation, it is possible for a NB-IoT UE to decode the NB Physical Broadcast Channel (NB-PBCH) without knowing the legacy Physical Radio Block (PRB) index. NB-IoT supports both downlink physical control channel (NB-PDCCH, or NB-M-PDCCH) and downlink physical shared channel (PDSCH). The operating mode of NB-IoT must be indicated to the UE, and currently 3GPP considers indication by means of NB Secondary Synchronization Signal (NB-SSS), NB Master Information Block (NB-MIB), or perhaps via other downlink signals.
The references signals used in NB-IoT are expected to follow the general design principles seen in LTE. For example, downlink synchronization signals for NB-IoT operation may include a NB Primary Synchronization Signal (NB-PSS) and a NB-SSS.
In half duplex (HD) or more specifically. HD Frequency Division Duplex (FDD), the uplink (UL) and downlink (DL) transmissions take place on different paired carrier frequencies but not simultaneously in time in the same cell. This means the UL and DL transmissions take place in different time resources. Examples of time resource are symbols, time slots, subframes, transmission time intervals (TTIs), interleaving times, etc. In other words. UL and DL (e.g., subframes) do not overlap in time. The number and location of subframes used for DL, UL or unused subframes can vary on the basis of a frame or a multiple of frames. For example, in one radio frame (say frame #1) subframes #9, #0, #4 and #5 are used for DL, and subframes #2 and #7 are used for UL transmission. But in another frame (say frame #2) subframes #0 and #5 are used for DL and subframes #2, #3, #7 and #8 are used for UL transmission.
One issue recognized herein is that a NB-IoT or eMTC device (henceforth a wireless communication device or "WCD") operating in half duplex (HD) mode will lose frequency synchronization to the network node when configured with a high repetition factor for uplink transmissions. The repetition factor may be referred to as "bundle size." Affected uplink transmissions include: (a) UL control channel transmission, e.g., PUCCH for eMTC and NB-PUCCH for NB-IoT: (b) UL data channel transmission, e.g., PUSCH for eMTC and NB-PUSCH for NB-IoT; (c) physical random access channel transmission, PRACH for eMTC and NB-PRACH. For eMTC, the repetition factor may be as large as 2048, meaning that the transmission is repeated in 2048 consecutive UL subframes (or more if there are invalid UL subframes). For NB-IoT devices, operating over a smaller bandwidth (one sixth of the eMTC bandwidth), even larger repetition factors are anticipated. During the time of the repeated transmissions, a WCD operating in HD cannot receive on the downlink, and, therefore, cannot stay tuned to the downlink carrier frequency.
Large repetition factors are typically used to facilitate maintained connectivity when the WCD is operating in an enhanced or extreme coverage scenario. For example, assume that a given value or lower range of received signal level defines "normal" coverage operation. Enhanced coverage operation may then be understood as operating with lower-than-normal received signal levels, e.g., Signal-to-Noise-and-Interference-Ratios (SINRs) down to −15 dB. There may be further levels of enhanced coverage, such as an extreme coverage scenario involving −15 dB>SINR>=−20 dB.
High repetition factors—large bundle sizes—provide for operation in such coverage scenarios, but it is recognized herein that large bundle sizes create other problems. For example, UL transmissions with larger repetition result in frequency drift at the transmitting HD WDC because: 1) the extended time the HD WCD is tuned away from the downlink carrier, and 2) heating of circuitry in the HD WCD from continuous operation of the power amplifiers (PAs) in the HD WCD. When operating in enhanced or extreme coverage, the HD WCD typically uses its maximum transmit (TX) power, making the PA by far the largest power consumer in the modem of the HD WCD. For example, the power consumed by the PA during such times may be at least an order of magnitude larger than the whole baseband circuitry of the HD WCD. As a further example, a commercial Cat4 LTE modem operating with full throughput on downlink and uplink and using maximum transmit power uses about 57% of its total power on the PA and only 7% and 9% on DL and UL baseband processing, respectively.
The temperature changes impact the voltage controlled crystal oscillator (VCXO) of the HD WCD. The VCXO frequency increases or decreases in dependence on the temperature and on the time derivative of the temperature. See FIG. 1, which plots example behavior.
Crystal oscillators that are temperature compensated, referred to as TCXOs, display less frequency deviation in response to temperature changes, but TCXOs have drawbacks when it comes to their frequency response to voltage control. Plus, TXCOs are more expensive than VCXOs. Hence, WCD vendors prefer VCXOs. This fact is particularly important for NB-IoT and eMTC devices, because low device cost is required for achieving a significant penetration of their intended markets.
To achieve acceptable performance when receiving low-power or low-level signals, a network base station, such as an eNB or eNodeB in LTE parlance, accumulates the repeated transmissions from a HD WCD directly before rate restoration, after rate restoration and/or after attempting to decode the message (decoder branch metrics of soft bits). The effect of frequency drift at the HD WCD over the course of its repeated uplink transmissions introduces a gradual change in the received messages at the base station, even though the radio channel as such may be stationary. The change may introduce destructiveness in the coherent combining of sequentially received messages, and will additionally contribute to inter-carrier interference (ICI) and inter-symbol interference (ISI). At the same time, due to the enhanced or extreme coverage scenario and the resulting low SNR operating point, it is challenging for the network node to estimate and compensate for the drifting WCD carrier frequency.
Moreover, the frequency drift in the HD WCD results in time drift, whereby the timing at which the Orthogonal Frequency Division Multiplex (OFDM) symbols, or single- or multi Lone symbols transmitted by it gradually changes. Those changes lead to inter-symbol interference (ISI), as well as to a gradual phase change of the received signal (linear phase). Both ISI and gradually changing linear phase introduce additional destructiveness in the coherent accumulation carried out by the receiving network node.

Methods and apparatus for synchronization of communication devices operating in half duplex mode