The invention relates to a process for the manufacture of a shaped part of ultra high molecular weight polyethylene (UHMWPE) comprising melt processing, wherein a) the UHMWPE has a weight average molecular weight (Mw) of at least 1*106 g/mol, b) during the shaping the storage plateau modulus of the UHMWPE (G*) is kept at a value of at most 1.5 MPa, c) whereafter, before the cooling, the G* is raised to its final value. The invention further relates to a shaped part obtainable with the process and the use of the shaped part in a medical application.

Such a process is known from WO 03/037590. In this publication a shaped part of UHMWPE is prepared wherein the UHMWPE is annealed for at least one hour at a temperature of between 130 and 160° C. in order to obtain a low chain entanglement and thus processability.
The processability of a synthetic polymer is often a compromise between the ease of processing and desired product properties. Processing routes conventionally applied in the polymer industry are injection moulding, extrusion and blow moulding. All these routes start from a melt of the polymer. Melt properties are mostly affected by the molecular mass of the polymer.
For a melt consisting of relatively low molecular mass polymer (MW<MC) there is a direct proportionality between zero-shear viscosity (η0) and molecular mass, whereas for a melt consisting of high molecular mass polymer (MW>MC) the viscosity depends much more strongly on the molecular mass (η0˜(MW)3,4). Herein is MW the weight averaged molecular mass and MC the critical molecular mass, which is related to the shortest polymer chain length able to form an entanglement. This difference in viscosity of the two molecular mass regimes is due to the ability of long chains to entangle, which imposes a restriction on the flowability of a melt.
The motion of chains within a highly entangled melt is described by the reptation model introduced by De Gennes in J. Chem. Phys. 55, p. 572 (1971). In this model a chain within a melt moves in worm-like fashion through a virtual tube, which is delineated by entanglements formed by neighbouring chains. The time needed for a chain to renew its tube (reptation time), i.e. to change its position within the melt is also highly dependent on molecular mass (τ0˜MW3). These fundamental restrictions make high molecular mass polymers rather intractable via conventional processing routes. On the other hand, final properties like tenacity, strength and wear improve with increasing molecular mass. Superior properties are necessary to meet the requirements of demanding applications.
The discrepancy between intrinsic properties related to high values of molecular mass and insufficient product performance due to difficulties in processing is encountered in UHMWPE as well as in other polymers of very high molecular mass. UHMWPE is a linear grade polyethylene, as is high-density polyethylene (HDPE), but possesses a weight average molecular mass (Mw) of at least 7,·5*105 g/mol (according to ASTM D4020). Preferably the UHMWPE has a weight average molecular mass of at least 3*·106 g/mol, because of excellent mechanical properties.
The density of the entanglements seems to play a prominent role in the process of forming a shaped part from the melt. The effect of entanglement density was confirmed by drawing experiments on single-crystal mats from UHMWPE, as reported by T. Ogita et al. in Macromolecules 26, p. 4646 (1993). In the case of melt crystallised UHMWPE, entanglements are trapped upon crystallisation and limit the extent to which the chains can be drawn. On the other hand, crystallisation of long molecular chains out of semi-dilute solutions leads to a much less entangled system and this enables these materials to be drawn below the melting temperature. It has always been believed that once a disentangled state of UHMWPE has been achieved, the formation of entanglements within the melt will be very slow, due to a long reptation time, and consequently one would be able to benefit from a disentangled state during processing. Experimental results however showed that highly disentangled solution crystallised films of UHMWPE, which are drawable below the melting temperature lose their drawability immediately upon melting. This phenomenon has been associated with that of "chain explosion", as experimentally assessed by P. Barham and D. Sadler in Polymer 32, p. 939 (1991). With the help of in-situ neutron scattering experiments they observed that the chains of highly disentangled folded chain crystals of polyethylene increase the radius of gyration instantaneously upon melting. Consequently the chains entangle immediately upon melting, which causes the sudden loss in processability and drawability once the sample has been molten.
These results showed that the fundamental restrictions resulting from the strong dependence of the zero-shear viscosity on molecular mass cannot be easily overcome. Simple disentanglement of the chains prior to melting will not lead to a less entangled melt and accordingly it cannot be used to improve the melt processability of UHMWPE.
The objective of the present invention is to provide a process for the manufacture of a shaped part of ultra high molecular weight polyethylene (UHMWPE) comprising melt processing, which part shows good processability below its melting point, and wherein the state of disentanglement is maintained long enough in the melt to process it as an only partly entangled melt.
According to the present invention this objective is achieved with a process wherein:    a) the UHMWPE has a weight average molecular weight (Mw) of at least 1*106 g/mol,    b) during the shaping the storage plateau modulus (G*) of the UHMWPE is kept at a value of at most 1.5 MPa,    c) whereafter, before the cooling, the G* is raised to its final value.
The G* is determined under nitrogen with a rotational viscometer (rheometer), using a parallel plate geometry (diameter 12 mm). Samples for rotational viscometry were made using compression moulding. The circular preforms having a diameter of about 8 mm and a thickness of 1 mm were moulded at a temperature of 50° C. Each two minutes the pressing force was increased in seven steps to a maximum of 50 kN. Oscillatory shear measurements were performed in a frequency range of 0.1-100Hz at 180° C.
With the process according to the invention a shaped part can be made by melt processing out of ultra high molecular weight polyethylene. The part thus formed is still highly drawable below its melting point, which indicates that, even though the UHMWPE under the specified conditions is processed in the melt, it still has a low entanglement density.
Surprisingly it has been found that when using the specified UHMWPE, under the specified conditions, a separate annealing step can be omitted. The process of increasing entanglement is under the conditions of the present invention so much retarded, that a disentangled thermodynamically metastable melt is present for a sufficient large time to process the material.
The time during which the entanglement increases, resulting in a build-up of the storage plateau modulus G* to a final value of around 2.0 MPa (which is indicative for a highly entangled UHMWPE), is in most cases depending on the heating rate (Θ) of the polymer. When a dependence is observed, the build-up time increases with a decreasing Θ. If an extended processing time window is required, it is preferred that Θ is at most 5 K/minute; even more preferred at most 1 K/minute.
Also the starting value of G* is therefore of importance. The lower the G* of the used UHMWPE, the longer it takes to achieve the G*=2.0 MPa value. Therefore it is preferred that the initial value of the G* of the used UHMWPE is at most 0.75 MPa. For a given polymerization with a specific catalyst system, the resulting G* starting value is typically lower with lower polymerization temperature. Although from a mechanical properties point of view, the desired G* end-value is 2.0 (fully entangled material), for processing the UHMWPE the G* must be below 1.5 MPa, more preferably below 1.2 MPa.
The G* build-up time can be extended or reduced by polymerization temperature and/or processing heating rate. In fact, the slower the build up of the G* value during the shaping, the better it is for the processability of the UHMWPE, as it retards the increase in entanglement. Therefore it is preferred that the speed (v) at which the G* builds up during shaping, is less than 3 MPa/hour, more preferred even less than 0.5 MPa/hour.
After the shaping, the value of the then achieved G* is raised to its final value of around 2.0 MPa. The speed at which this is done, can be as high as the situation allows. This can be achieved by increasing the heating rate. The final temperature should preferably not exceed 450 K.
An additional annealing step, as taught in WO 03/037590, will increase that build-up time and therefore enlarge the processing window between the initial G* and the highly entangled stage (having a G* of around 2.0 MPa). Preferably this annealing is performed at a temperature of not less than 398 K and not more than 410 K. For more details on this annealing step, the reader is referred to the above indicated patent publication.
The UHMWPE that is used in the process of the present invention has to fulfill at least the following criteria:                the weight average molecular weight (Mw) is at least 1*106,        the storage plateau modulus (G*) is kept at a value of at most 1.5 MPa during the shaping.This requires specific conditions for the polymerization process in which the UHMWPE is made:        the temperature at which the polymerization takes place is between 225 and 325 K, more preferably between 260 and 305 K. The higher the temperature, the higher the G*-value of the resulting UHMWPE;        The catalyst is an unsupported single-site catalyst or a mixture of unsupported single-site catalysts, known for the polymerization of ethylene to UHMWPE;        The catalyst concentration is low: less than 1*10−4 mol/l, more preferred less than 1*10−5 mol/l.        The polymerization temperature is lower than 325 K and preferably lower than 300 K.        As of this nature, the polymerization takes place initially in solution and after formation and precipitation of polymer in suspension.
The UHMWPE can either be a homopolymer of ethylene, or a copolymer of ethylene with a comonomer in the form of another α-olefin or a cyclic olefin. Examples of such a comonomer are: propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, (substituted) norbornenes and the amount of incorporated comonomer should be sufficiently low to ensure that the polymer still crystallizes under polymerization conditions. Through simple experimentation the skilled man is able to find the suitable process conditions that result in the preparation of the UHMWPE fulfilling the above stipulated criteria. Preferably, the MWD of the UHMWPE lies between 1.2 and 3.0, more preferred between 1.2 and 2.5.
The invention also relates to a shaped part that is obtainable with the process of the present invention, as well as to the use of the shaped part. The shaped part can be in the form of a filament, a film, a moulded or extruded article. The processes to obtain such a shaped part from the polymer meet are known to the skilled artisan.
As the shaped parts according to the present invention have enhanced toughness, wear and abrasion resistance, reduced oxygen permeability, and are essentially grain boundary free, they are very well suited for the use in a medical application. Preferably the shaped part can thus be used as an element of a hip or knee prosthesis.
Also other uses, wherein the improved physical and mechanical properties of the shaped are applicable, can be referred to, like the use of the UHMWPE-based shaped part in bearings.
The invention is elucidated with the following non-limiting Examples and comparative experiments.

Process for the preparation of a shaped part of an ultra high molecular weight polyethylene


An exemplary method for updating acquisition list in a wireless communication device having a first transceiver and a second transceiver is disclosed. The acquisition list associated with the second transceiver. The exemplary method comprises updating a first category of entries of the acquisition list over a wide area network via the first transceiver and updating a second category of entries of the acquisition list by a user through input means on the wireless communication device.

Dual mode wireless communication devices, also known as mobile handsets, cellular phones, etc., include a cellular radio for connection to a wireless area network (WAN) and another wireless communication radio for connection to a wireless local area network (WLAN). An example of a WAN is a code division multiple access (CDMA) network, and an example of a WLAN is a 802.11 network. Presently, single mode wireless communication devices include a preferred roaming list (PRL) that is maintained and updated by a service provider. The service provider is typically the cellular network provider, which may also be referred to as a carrier. Typically, the PRL includes an acquisition index section and a system record section. The acquisition index section defines, among other things, the radio parameters for connecting to a particular system, for example, cellular or WLAN. The system records section defines a plurality of entries such as identification of the access points, for example, base stations or wireless access points, and authentication information.
The current arrangement presents various shortcomings. First, since the PRL is maintained by the service provider, the user will have limited or no ability to specify preferences and make unique modifications. These limitations will become even more aggravated as access points for WLANs become increasingly ubiquitous and installed on an ad hoc bases. In order to access these ad hoc networks, the user must contact the service provider in order to enable support for connection to these ad hoc networks which is inconvenient and results in consumer dissatisfaction.
Secondly, if the user makes modifications to the PRL, then subsequent updates to the PRL by the service provider may overwrite the previous modifications supplied by the user, result in unwanted loss of user data. In those cases where the user cannot make a modification to the PRL, the user will not have the ability to connect to certain ad hoc networks that are not supported by the service provider, thereby severely limiting the user's accessibility to WLAN devices.

Method for managing acquisition lists for wireless local area networks


Apparatus and method for supporting operations and maintenance (“OAM”) functionality in an OBS network is described. One embodiment is an OBS network having OAM functionality, the OBS network comprising a plurality of OBS nodes interconnected via links. Each of the OBS nodes comprises an OAM module (“OAMM”) for processing information regarding OAM functions in the OBS network and a routing manager (“RM”) for processing routing information; and wherein at least one wavelength in each of the links comprises an OAM/1 wavelength for OAM/1 transmissions between nodes, the OAM/1 transmissions comprising OAM activity information; wherein at least one wavelength in each of the links comprises a reference wavelength for providing a wavelength reference to which light generating devices in the OBS network lock; and wherein at least one wavelength in each of the links comprises a routing wavelength for providing routing information between nodes.

1. Technical Field of the Invention
The present invention generally relates to optical burst switching ("OBS") networks. More particularly, and not by way of any limitation, the present invention is directed to a method and apparatus for supporting operations and maintenance ("OAM") functionality in such networks.
2. Description of Related Art
In burst switching technology, such as, in particular, optical burst switching ("OBS") technology, data bursts ("DBs"), each of which is made up of multiple packets, are switched optically at core nodes, or routers, in the OBS network. A small control packet, called the Burst Header Packet ("BHP") travels an offset time ahead of each DB along the same DB route and configures the optical switch for the duration of the DBs at the core node. In short, each BHP travels an offset time ahead of its associated DB and establishes a path for the DB.
Two primary features distinguish OBS networks from other types of optical networks that one must bear in mind with regard to Operations and Maintenance ("OAM") issues in OBS networks. The first is that spectral (i.e., spatial) decoupling is used in transmitting a BHP and the DB associated therewith transparently from ingress to egress edge nodes with possible wavelength conversion for contention resolution at intermediate optical core nodes. As a result, both a proper mechanism to check on correlation between a DB and its associated BHP in the passage from ingress to egress edge nodes and a network-wide wavelength reference to offer wavelength standard to each node are required. Second, temporal decoupling between a BHP and its associated DB, which are modified/updated at each intermediate node, exists. This requires that timing information for each DB and BHP pair must be maintained until they reach the egress OBS edge node.
It is these two distinctive characteristics of OBS networks that may generate another set of OAM requirements and warrant a fresh look into OAM issues in connection with OBS networks. There are several potential OAM implementation problems in OBS networks caused by these features. Such potential problems include out-of-synchronization receipt of BHP and DB, orphan BHPs and DBs, optical switch fabric misconfiguration, burst misrouting, burstification process malfunction, and out of sequence arrival of bursts at the destination edge nodes, to name a few.
Operations and Maintenance ("OAM") architecture can be broken down into four main levels. The first such level is a functional architectural level, in which OAM architecture is considered in relation to OBS functionality. The second such level is a network architectural level, in which all necessary building blocks to provide OAM functionality on a network-wide level are identified along with their defined inter-relationships. The third such level is an informational and communication architectural level. This level addresses a model of communication, as well as an exchanged informational model among entities in the OAM architecture. The last such level is a node architectural level. This level describes how the previous three levels can be realized and integrated into an OBS node so as to achieve OAM objectives. At the node architectural level, the fundamental OAM building blocks needed to carry out OAM functions are provided and their interactions with other parts of the OBS node infrastructure are defined. In contrast to the network architectural level, focus at the node architectural level is on local OAM activities.
Currently in OBS networks, there is a lack of OAM functionality in the edge and core nodes to support performance monitoring, fault management defect and failure detection, and related information dissemination.

Method and apparatus for supporting operations and maintenance functionality in an optical burst switching network


A non-adhesive sputtering structure includes a sputtering target having a plate shape; and a backing plate having a plate shape. The backing plate faces the sputtering target, and facing surfaces of the sputtering target and the backing plate are in contact with each other. The backing plate includes a body having a longitudinal axis; and a cooling member through which a cooling material flows in a longitudinal direction of the body substantially parallel to the longitudinal axis. The cooling material conducts heat generated from the sputtering target from sputtering to outside the backing plate. The non-adhesive sputtering structure further includes a plurality of non-adhesive fastening members which maintain the facing surfaces of the backing plate and the sputtering target in contact with each other. The non-adhesive fastening members are extended through a thickness of the backing plate and correspond to regions of the backing plate excluding the cooling member.

(a) Field of the Invention
The invention relates to a glueless type connecting structure of a target and a backing plate, and more particularly, to a glueless type connecting structure of a target and a backing plate which directly connects a target with a backing plate without using an adhesive at the joint of the target and the backing plate.
(b) Description of the Related Art
In general, sputtering is used to form a wiring film for a thin film, optical recording and semiconductor field that are used in a liquid crystal panel and an organic electroluminescent panel. The liquid crystal panel and the organic electroluminescent panel are used for a television set, a notebook computer and other monitors.
In sputtering, atoms are separated from a target by applying plasma discharge between a substrate and a target that is a coated material such that an ionized gas hits against the target. The separated atoms are accumulated on the substrate, thereby manufacturing a thin film. The method has the advantage of forming a thin film having the same composition as the target, unlike vacuum depositing or ark ion plating ("AIP").
The target used in sputtering is generally soldered to a backing plate (also called, cooling plate or support body) which cools and supports the target. The backing plate includes copper or a copper alloy having relatively high thermal conductivity so as to cool the target heated in sputtering.
Regarding soldering between the target and the backing plate (support body), for example, Japanese Patent Application Laid-Open No. 2003-183822 discloses a sputtering target including a target material and a backing plate with a bonding material (e.g., soldered metal) therebetween. The backing plate has a recession for the bonding material and a groove communicating with the recession on the outer circumferential wall of the recession.
This document states that the target does not bend even if the bonding material is solidified and contracted, in the structure. However, the technology of Japanese Patent Application Laid-Open No. 2003-183822 is not directed to prevent separation of the bonding portion (soldered metal) from other elements, and particularly, has a problem in that it is necessary to use a backing plate having a complicated shape.
Japanese Patent Application Laid-Open No. 1996-246144 discloses a technology for preventing a target from bending and cracking and a soldered portion from separating, by disposing plates having larger and lower thermal expansion rates than the sputtering target on opposing surfaces of the backing plate such that the backing plate is interposed between the plates. Interposing the backing plate between the plates prevents the backing plate from bending and provides the sputtering target with the same thermal expansion property as the target to be supported. However, this technology also has a problem in that the structure of the backing plate is complicated.
Japanese Patent Application Laid-Open No. 1998-046327 discloses a method of making a target and a backing plate of an aluminum alloy in order to reduce the difference in a linear expansion rate between the two members. However, the difference in thermal expansion rate is not sufficiently and surely reduced in the composite of the target and the backing plate according to the technology, such that it is difficult to suppress cracks in a soldered metal. Further, when the backing plate includes the same material as the target which including an Al—Nd alloy, the cost is correspondingly increased.

Non-adhesive sputtering structure including a sputtering target and backing plate


The invention provides new methods for screening libraries of peptides and other compounds for a desired property in eucaryotic cells. The methods are premised, in part, on the unexpected observation that the contents of procaryotic or lower eucaryotic cells, such as yeast, can be transferred to recipient eucaryotic cells in an essentially clonal manner by protoplast fusion of the respective cells. Applications of the methods include screening peptides in eucaryotic cells substantially incapable of episomal replication of transferred nucleic acid fragments; screening in eucaryotic cells peptides or secondary metabolites produced in procaryotic cells; and screening a library of peptides for capacity to bind a selected RNA in eucaryotic cells.

In recent years, a number of in vitro methods have been developed for screening polypeptides for a desired binding specificity. For example, the phage display technique screens polypeptides displayed as a coat protein from a bacteriophage. See, e.g., Dower et al., WO 91/17271; McCafferty et al., WO 92/01047.; Ladner, U.S. Pat. No. 5,223,409 (incorporated by reference in their entirety for all purposes). Another in vitro screening method has been developed for isolating nucleic acid sequences that bind to proteins. See Gold et al., U.S. Pat. No. 5,270,163.
In vivo methods for screening libraries have also been reported. Such methods usually detect protein-protein or protein-nucleic acid interactions using reporter constructs to identify active members of a library (Allen et al., 1995). For example, a yeast three-hybrid system has been used to identify a cDNA encoding a protein that binds the 3' end of histone mRNAs, and bacterial reporter systems based on transcriptional antitermination or translational inhibition have been used to screen RNA-binding libraries in several different contexts (Fouts et al., 1996; Harada et al., 1996, Jain et al., 1996; Wilhelm et al., 1996). These methods are especially useful for screening cDNA expression libraries and, arguably, mimic physiological conditions more closely than the in vitro methods. Further, such methods allow screening for physiological or functional properties as distinct from merely binding activity. In vivo screens are usually performed in bacteria or fungi, such as yeast, because of high transformation efficiencies and because it is possible to transform many cells and obtain individual clones.
Because many libraries are screened to obtain therapeutic compounds and mammalian cells more closely simulate the environment of intended therapeutic use than procaryotic, yeast or in vitro screens, it would be desirable to screen libraries in mammalian cells. For example, protein folding or posttranslational modification of some peptides may be different in eucaryotic and procaryotic cells. Screening in mammalian cells is, however, generally more difficult than screening in procaryotes because: (1) transfection efficiencies are lower; (2) unlike bacteria or yeast where plasmid segregation results in clonal colonies, transfection of mammalian cells is believed to involve the uptake of a large population of plasmids; (3) in general, eucaryotic cells do not support episomal replication of plasmids, (4) establishment of stable eucaryotic cell lines with integrated vector is laborious and may not result in expression of many library members, (5) recovery of a selected vector from eucaryotic cells can be difficult.
Some progress has been reported to address these difficulties. Transfection efficiencies have been reported to be improved using liposomes, protoplasts, or retroviruses as delivery vehicles (Schaffner, 1980; Sandri-Goldin et al, 1981; Rassoulzadegan et al., 1982, Felgner et al., 1987; Kitamura et al., 1995). Selected plasmids have been reported to have been enriched from pools introduced into a cell by transfection by subdividing active pools and performing multiple rounds of enrichment (Seed, 1995). Further, plasmid recovery has been reported to be improved using episomally replicating plasmids containing SV40, polyoma, or Epstein Barr Virus (EBV) origins in specific cell types supporting episomal replication of such plasmids (Yates et al., 1985; Seed et al., 1987; Kinsella et al., 1996). Thus, for example, a cDNA expression cloning strategy has been reported by Seed et al., 1987 using plasmids containing an SV40 origin. This origin allows the plasmids to replicate episomally to high levels in COS cells, which express large T-antigen. SV40-vector libraries, were introduced into COS cells by protoplast fusion, the libraries were amplified episomally, and cells expressing the CD2 surface antigen were isolated by panning with antibodies, and amplified vectors were recovered from Hirt supernatants of the isolated cells.
Despite some progress as noted above, difficulties and limitations remain in screening libraries in eucaryotic cells, and improved methods are needed.

Reagents of the University of California


A method for handling packets is disclosed. The method can include providing at least one main processor connected to a plurality of offload processors by a memory bus; configuring the offload processors to provide security related services on packets prior to redirection to the main processor; and operating a virtual switch respectively connected to the main processor and the plurality of offload processors using the memory bus, with the virtual switch capable of receiving memory read/write data over the memory bus.

Packet handling and security applications can require a significant amount of scarce computational resources in enterprise server or cloud based data systems. These can include services such as packet repeaters, intrusion detection systems (IDS), intrusion protection systems (IPS), and routing mechanisms for virtual private networks (VPNs). Many proprietary and incompatible hardware systems are available for such packet handling and transport services, but cost and a desire for standardization pushes enterprise data storage and processing providers toward software defined stacks running on commodity (e.g., x86 architecture) hardware.
Unfortunately, processors based on x86 architectures are ill-equipped to handle such high volume applications. Even idling, x86 processors use a significant amount of power, and near continuous operation for high bandwidth packet analysis functionality make the processor energy costs one of the dominate price factors. In addition, issues with the high cost of context switching, the limited parallelism, and the security implications associated with running encryption/decryption modules on x86 processors have reduced the effectiveness of enterprise or cloud data security.

This patent is subject to a terminal disclaimer.

Efficient packet handling, redirection, and inspection using offload processors


A data encryption/decryption system comprising a cryptographic interface operatively coupled between a host device and a data storage device is disclosed. The host and data storage devices include respective IDE controllers supporting full ATA protocol. The cryptographic interface includes a host device-side IDE controller and a data storage device-side IDE controller, each controller supporting partial ATA protocol. The cryptographic interface also includes a cipher engine adapted to transparently perform real time data ciphering during IDE/ATA data transfer between the host and data storage devices in conjunction with the host device-side IDE controller and the data storage device-side IDE controller.

Integrated Drive Electronics (IDE) is a standard electronic interface used between a computer motherboard bus and disk storage devices. IDE has been adopted as a standard by American National Standards Institute (ANSI), whereby the ANSI designation for IDE is Advanced Technology Attachment (ATA). IDE/ATA also refers to the electronic protocol used by computers or host devices to transfer data to/from data storage devices. There are two data transfer methods used in IDE: Programmed Input/Output (PIO) and Direct Memory Access (DMA). In PIO mode, the data transfer is initiated and performed by the host device or processor. In DMA mode, data transfer is controlled by signals for handshaking between the host device and the data storage device.
When proprietary information is kept in storage media where physical access control cannot be assured, data encryption and decryption provides a mechanism for protecting data from unauthorized access. Data may be cryptographically protected by encrypting data as it is sent from a host device to a data storage device, and decrypting the stored data as it is retrieved from the data storage device upon request by the host device.
In a conventional data relay approach, data is transferred via an IDE bridge or interface placed in series between a host and a data storage device. This type of data transfer traditionally requires that the IDE interface implement an IDE controller supporting full ATA protocol on each side of the IDE interface for data buffering/dataflow control. The IDE interface simultaneously plays the role of a virtual host device with the data storage device and the role of a virtual data storage device with the host device during IDE/ATA data transfer. The problem with the data relay approach is that the IDE interface needs to implement large data buffers to maintain dataflow control. Such large data buffers are often implemented on an IDE application specific integrated circuit (ASIC) using costly static random-access memory (SRAM) macros or the like, which results in high chip manufacturing costs.

Real time data encryption/decryption system and method for IDE/ATA data transfer


A toy that can be assembled by a child. At least one first block element consisting of a rod made of a flexible material including a fitting terminal at one end or opposite ends thereof is provided. The fitting terminal has at least one fitting projection thereon. A second block element has a plurality of fitting holes each adapted to be fitted onto one of the fitting projections. The first block element and the second block element are combined with each other during an assembling operation so as to exhibit a desired three dimensional configuration. Each fitting terminal is provided with a plurality of fitting projections projecting from the outer surface of the fitting terminal so that the fitting projections can be selectively fitted into one of the fitting holes on the second block element. The rod constituting the first block element is composed of a plastically deformable core and a flexible sheath molded of a soft synthetic resin surrounding the core. The sheath is integrated with the core to form an integral structure. The core is composed of a wire-type material having shape memory characteristics.

1. Field of the Invention
The present invention relates generally to a toy that can be assembled by a child independently. In particular, the present invention is a toy having a predetermined structure which can be assembled by the child by combining a plurality of structural elements, each designed in a block-shaped configuration with each other.
2. Description of the Related Art
A toy of the foregoing type, assembled to provide a predetermined structure or exhibit a predetermined configuration by combining a plurality of block elements with each other, is conventionally known. In such a toy, block elements are used to form or build a toy. Fitting projections, and fitting holes to be fitted onto the fitting projections, designed so as to conform with a common standard, are formed at predetermined positions of each block element. When the toy is assembled by a child, fitting projections on one block element are fitted into fitting holes formed on other block elements.
Since the conventional toy is assembled by using block elements each having a predetermined rigid configuration which cannot be changed during an assembling operation, the elements cannot be plastically deformed so as to assume a desired configuration.
For this reason, the appearance of the assembled toy and a sensory perception derived therefrom are very hard or rigid. Consequently, with such a conventional toy, that a soft flexible feeling cannot be obtained from the toy after assembly of the toy is completed.
In addition, since a hard material which cannot plastically be deformed is employed as a raw material for all the block elements to be used for a toy, and a specific configuration-is imparted to the material, block elements cannot be joined to each other using other block elements which are dimensioned to have a small diameter like a string or cord.

Toy that can be assembled independently by a child


A vehicular pedal supporting structure includes a pedal bracket, a pedal, and a guide. A front portion of the pedal bracket is fixed to a first vehicle-body-side constituent member, while a rear portion of the pedal bracket is extended toward a rear of the vehicle. The pedal is supported on lateral side portions of the pedal bracket so as to be swingable around a center shaft. The guide causes the rear portion of the pedal bracket to be displaced backwards and downwards when the pedal bracket is displaced backwards as a result of application of a frontal external force to create a rotational displacement of the rear portion of the pedal bracket relative to the front portion. The pedal bracket is provided with a rupture creation mechanism for ensuring that the rear portion of the pedal bracket is at least partially ruptured from the front portion thereof when the rear portion is rotationally displaced.

1. Field of the Invention
The invention relates to a vehicular pedal supporting structure capable of displacing a trodden face of a pedal substantially forwards with respect to a vehicle when a pedal bracket is displaced backwards with respect to the vehicle together with a vehicle-body-side constituent member as a result of application of a predetermined external force from the front side of the vehicle.
2. Description of the Related Art
Heretofore, various arts for controlling displacement of a vehicular pedal such as a brake pedal or the like in the case of application of a predetermined external force from the front side of a vehicle have been developed for the purpose of improving the performance of protecting passengers. One of such arts is proposed by the present applicant and is disclosed in Japanese Patent Application No. 10-236288. This art will be outlined below.
As shown in FIG. 12, a brake pedal 150 of suspension type is swingably supported by a pedal bracket 152. The pedal bracket 152 has a generally U-shaped longitudinal cross section with an open bottom. A base plate 154 generally in the shape of a rectangular flat plate is welded to a front end portion of the pedal bracket 152, and constitutes part of the pedal bracket 152. The base plate 154 is fixed to a dash panel 156 inside a cabin, whereby the front portion of the pedal bracket 152 is mounted to the dash panel 156.
On the other hand, an instrument panel reinforce 158 as a high-strength member is disposed substantially behind the dash panel 156 with respect to a vehicle, with the longitudinal direction of the instrument panel reinforce 158 being substantially coincident with the lateral direction of the vehicle. A slide guide 160 is disposed protruding substantially forwards with respect to the vehicle, and a guide face (inclined face) 160A is provided on a lower face of the slide guide 160. A base end portion of the slide guide 160 is fixed to the instrument panel reinforce 158 at a predetermined position in the longitudinal direction. An angle-like coupling bracket 162 is fixed to a tip end portion of the slide guide 160. Correspondingly, a slide guide bracket 164 having a generally U-shaped cross section is stuck to an upper rear-end portion of the pedal bracket 152. A top wall portion of the slide guide bracket 164 and a bottom wall portion of the coupling bracket 162 are connected by a rivet 166.
According to the aforementioned arrangement, if the dash panel 156 is displaced substantially backwards with respect to the vehicle when a predetermined external force is applied from the front side of the vehicle, the rivet 166 connecting the slide guide bracket 164 and the coupling bracket 162 together is sheared. Thus, the slide guide bracket 164 and the coupling bracket 162 are disconnected from each other. As a result, the slide guide bracket 164 comes into abutment on the guide face 160A of the slide guide 160, and then slides along the guide face 160A substantially downwards with respect to the vehicle. During this sliding movement of the slide guide bracket 164, the pedal bracket 152 is plastically deformed and rotationally displaced around the front end side thereof substantially downwards with respect to the vehicle. As a result, a pedal pad 168 of the brake pedal 150 is displaced substantially forwards with respect to the vehicle.
If a rotational displacement structure based on a slide mechanism as described above is adopted herein, a load input to the dash panel 156 is input to the slide guide 160 and hence to the side of the instrument panel reinforce 158 via the pedal bracket 152. In general, it is preferred that the load thus input to the side of the instrument panel reinforce 158 be low.
Further, a vehicular pedal supporting structure of this sort often tends to be mechanically complicated. Basically, however, if this vehicular pedal supporting structure adopts a simple mechanism with a reduced number of parts, it is easier to guarantee operational reliability, and a reduction in cost is achieved as well. It can be concluded, therefore, that structural simplification is also an important theme to be pursued.


A means for winding orthogonal coil systems that almost completely encompass and closely conform to magnetic media having a circular cylindrical form and orientation, including such media further encased in square or rectangular cassettes, cartridges or disk drives, while providing necessary access to that volume without the use of drawers and separable connectors or flexible lead wires for connection of the coils to energy stored in capacitors. The invention further employs hard wired circuitry for controlling the phase of currents in the coils and maintaining the desired rotation of the magnetic field. While this invention can be realized to degauss media inserted and extracted through the same side of the winding system, it is equally configurable to conveyance of media in one end of an orthogonal coil system and out of the opposing end. In one embodiment of this invention, the media size is measured for the purpose of positioning it properly for degaussing an entire media unit such as a tape reel, such positioning being limited to at most two positions for the case of rectangular housings such as tape cassettes that contain two reels or disk drives with disks on one end and head motors on the opposing end.

1. Field of the Invention
The present invention relates to a bulk degaussing system for erasing of various magnetic media generally used for the storage of information; the system including a pair of coils wound with intersecting axes, for example, orthogonal to each other and in close conformance to a predetermined media volume while still allowing full access to the interior of the coil for purposes of loading it with media. The invention further relates to a control circuit for correcting phase error of electrical currents in the coils toward a predetermined optimum phase, for example, a phase of 90.degree., for the case of orthogonal coils such that the vector sum of the magnetic fields uniformly rotates the resultant field in the plane defined by the intersecting axes of the coils. The invention further relates to automatic loading and optimal positioning of the variety of media form factors commonly encountered in the art.
2. Description of the Prior Art
Various degaussing systems for erasing magnetic media are known in the art. For example, although not applied to magnetic media in bulk, U.S. Pat. No. 2,962,560 discloses a system which utilizes decaying AC magnetic field as an optimal degaussing process. The system in the '560 patent applies a damped sinusoidal field along an information-bearing track of a revolving magnetic drum, exposing each point on the track to a field that reverses and decays.
In more recent art, in which individual tracks on magnetic tapes are erased, several factors including the period of a sinusoidal AC field of constant amplitude; the weakening of that field with distance from its source, such as an erase head; and the motion of tape with respect to that source; cooperate to cause the decaying AC effect, which generally serves to reduce tape noise by randomizing the state of the magnetic domains. Disk drives generally re-use tracks by overwriting them; however, application of track-width fields ranging from DC to random bit patterns are also known to have been used for information erasure.
Bulk degaussers are used in general in the erasure of magnetic tape when tape recorders lack such function, in which case a decaying AC field is generally used in order to erase the tape so it can be reused. In the case of a disk drive, bulk degaussing can destroy and thereby protect information, for example, when the write mechanism fails but the read mechanism remains operational. The prior art also extends bulk degaussing to protection of information on tapes. Bulk degaussers erase media faster and more thoroughly than tape recorders and disk drives and relieve the operating stress required for recorders and drives to erase media.
Bulk degaussers generally apply large magnetic fields to media in the form of tape wound on reels in tight spirals approaching concentric cylinders or concentric circular tracks on flat disks stacked in a disk drive. The effectiveness of the intended information erasure depends both on the strength of the magnetic field and its direction or range of directions relative to the information-bearing tracks on the tape and disks. The circular direction of tracks on disks and tape reels is the single most effective direction, and degausser configurations suited to apply that direction to either form can generally apply it to the other form about as well.
The strength of the degaussing field must exceed the variable switching strength of the magnetic domains in the media. Increasing the strength in a single magnetic direction beyond a few multiples of the average switching strength or the coercivity rating of the media fails to improve the erasure effect for some common media formulations. Conversely, the application of a sequence of magnetic directions generally greater than the coercivity erases the media better than a very strong field applied in a single direction.
Given the synergistic effect of radial and axial field directions being about equal to each other, and the fact that nearly cylindrical tape surfaces and circular disk surfaces reverse the orientation of tracks relative to those radial and axial directions, coil systems that rotate magnetic fields in the plane perpendicular to the axes of reel and disk forms generally erase both forms well, and coil systems that add axial directions to the sequence of magnetic fields erase even better.
Many of the prior art bulk degaussing systems employ magnets formed from inductive coil systems that are incapable of generating magnetic field volumes the size of the largest units of magnetic media to be degaussed. Such systems require a relatively long energized time period in order to mechanically transport media through the magnetic field of a coil system and to rotate the field relative to the media. Such art generally draws relatively continuous power from a source, such as an AC supply circuit, to make up for losses, for example, due to the inevitable resistance of the inductive coils. The power supplies for such systems, typically 120 Volts and 15 Amperes, places practical limits on degaussing coil systems, and the resulting strength and volume of the degaussing field that they generate.
Degaussers generating magnetic fields over long periods of time often necessitate energy storage components other than the inductive coils, such as capacitors, to improve the power factor of the inductive coils and to store large quantities of resonant energy in order to increase degaussing strength. Such prior art degaussers are often configured with coils wound on iron cores. These degaussers also generally incorporate switching circuits for limiting operation to periods when media is present or for converting the supplied AC power into a DC current.
A fundamental aspect common to such prior art systems is that the inductive coils always operate in association with their supplemental energy storage and dissipating components with a response forced by their power supplies and the associated switching components. Such responses generally go to the steady state response in a period much shorter than the operating period of the magnet.
Many coil and core geometries have been devised to concentrate, direct and shape small steady state magnetic fields. Likewise, arrays of magnets (coils with or without cores) and many combinations of linear and rotational motion, either of the magnets or of the media or both, have been applied to rotate or otherwise vary the direction of the magnetic field beyond 180.degree. reversals while distributing it over the entire bulk of the magnetic media. Examples of such systems are disclosed in U.S. Pat. Nos. 2,481,392, 3,023,280, 3,938,011, 3,588,623, 4,346,426, 4,467,389, 4,639,821, 4,730,230, 4,751,608, 4,897,759, and 5,204,801.
When the magnetic field is smaller than the media volume, such as in the steady state prior art discussed above, mechanical failures can compromise the degaussing process. Commercial bulk degaussers, such as Model 905-, 930-, 940-, and 943-series, manufactured by Data Security, Inc., disclosed in U.S. Pat. Nos. 4,751,608 and 5,721,665, detect exceptions to such operation. These systems automatically compensate in certain cases where interactions between a load of media and the magnetic field causes predetermined motions to deviate. Even so, a human operator may misinterpret motion variations as an undetected failure, or may ignore warning indicators precipitated by an anomaly for which compensation has not been provided.
U.S. Pat. No. 3,879,754 discloses a system with multiple coils wound orthogonal to each other around cores and operating in forced response to power supplies, which may include AC excitation of one set of coils simultaneous with DC excitation of the orthogonal set of coils. Like the other prior art discussed above, the '754 patent illustrates a system with a small magnetic field volume relative to a much larger moving bulk of magnetic media. The coils of that invention, at least superficially, resemble orthogonal coils that can rotate magnetic fields electronically.
U.S. Pat. No. 4,423,460 discloses a system which rotates a magnetic field electronically using coils wound on orthogonal cores and driven toward a steady state forced response in cooperation with passive phase shifting. Complementary phase shifting of plus and minus 45.degree. is used to improve the power factor from near zero to 0.71, which may serve to reduce line current while increasing field strength. Even so, its media-sized volume and steady state operation limit the field strength that can be generated for a particular supply circuit rating. The system also discloses motion of the media but does not disclose detection nor measurement to place media within or convey it past the rotating field.
U.S. Pat. No. 2,962,560 discloses a system with a switched LC circuit which includes a capacitor initially charged to a voltage for the purpose of storing energy. Switch closure transfers energy into an inductor. Unlike the resonant energy storage function of capacitors in degaussers operating coils to the steady state, a supply circuit of low power delivers energy to charge the capacitor to predefined voltage and energy storage levels over a long period during which the coil is switched off, offering transient degaussing strength and field volume independent of the supply circuit rating.
As long as some inevitable electrical resistance remains well under a value critical to the values of capacitance and inductance, the natural transient response of such under-damped second order series LCR circuitry is an exponentially decaying sinusoid, where the values of inductance and resistance alone dictate the rate of decay, and the values of capacitance and inductance approximately dictate the frequency of the sinusoidal oscillations; the influence of the resistance on that frequency being limited by its value well under the critical damping value.
U.S. Pat. No. 4,551,782 discloses switched LC circuits capable of exponential AC decay, describing the resulting transient operation as "magnetic fields in alternating directions at successively decreasing amplitudes." That system employs one coil to generate a field the size of the media in the direction parallel to the axis of the media. A second coil situated with its axis orthogonal to the first coil is not symmetrically disposed about it or situated to generate a field the size of the media. Therefore, this system does not electrically rotate the field over the direction of the tracks, but rather it rotates the media through the second coil at a rate much faster than the oscillatory period of the sinusoidal field in order to achieve the desired decaying exposure.
The transient natural response of an LC circuit from a state of initial stored energy can be termed a "ringing signal generator" as in U.S. Pat. No. 5,270,899. That fundamental response offers the most direct means for synthesis of the desired decaying AC field. Even if a non-exponential decay rate or non-sinusoidal oscillation were desired, means such as digital synthesis and linear amplification, are not generally suited to the current and voltage levels or the component impedances of practical bulk degaussers. That system applies indexed motion alternating with generation of that decaying AC field smaller than a unit of media to expose all of the media. It measures the size of the media to calculate the number of degaussing positions desired or indexes motion in predetermined increments or both.
While the small transient field of such prior art does limit the energy storage requirement, problems can arise in its practice. First, the calculation of indexed motion increments is not clear-cut in all cases. Second, the application of magnetic fields can exert mechanical forces with the potential to physically move the media. Eddy currents, caused by oscillatory fields, generally act to center or levitate non-ferromagnetic conductors like aluminum housings and thus reduce friction between media and conveyance. Such levitation can complement attraction or repulsion of soft magnetic materials or permanent magnets used in head and spindle motors of disk drives and in a variety of other uses. Thus, if the art is applied to erasing a variety of media formats, a variable potential for positioning errors arises due to unintended media motions.
Addressing such unintended motion errors with mechanical restraint increases the system complexity, especially in the case of processing a large variety of media. Straightforward restraints like straps add to the thickness of media and thus to the volume required for the magnetic field, adversely impacting on the energy storage requirement of such systems.
Some known degaussers, such as manufactured by Sanix Corporation, are known to utilize transient field degaussers with coils that encompass media completely and so do not measure media size to calculate linear erasing positions. They do index rotation to change the direction of the field between successive transient fields.
Users of bulk degaussers view media-sized magnetic fields as a means to minimize failure-induced loss of efficacy. Degaussing systems that electrically rotates such fields do so with multiple coils. In some systems, even if one coil fails, the other coil still exposes the media volume, and even though it generates a field of sub-optimal direction with respect to much of the media volume, it can still erase those regions significantly.
U.S. Pat. No. 3,143,689 discloses a system which completely encompasses the degaussing field volume within a set of closely conforming coils, wound orthogonal to each other. This system requires a drawer for the inner coil in order to load media into that volume. Separable electrical connectors allow the drawer to operate and its coil to connect to a capacitor and switching circuitry. Flexible lead wires to the drawer may be impractical due to necessarily large wire size. Rather than relying on the natural transient response, this system connects capacitors directly to its coils and switches energy from another capacitor into the LC circuits with vacuum tubes driven by an oscillator, thereby providing the capability to force a resonant response in the circuits. It further offers means to vary the biases on the grid voltages relative to each other, which should change the direction of the plus and minus 180.degree. oscillatory field over 90.degree.. Its operation should yield the adequate rotation and transient decay effects if that bias is adjusted between its limits more slowly than the oscillations but more rapidly than circuit losses drain energy from the third capacitor.
U.S. Pat. No. 4,617,603 illustrates a typical solution for the avoidance of separable connectors in order to access a media-sized volume. The windings are disposed over only part of the surface defining the degaussing volume, leaving openings for access to the volume. It has been reported that the rotating field generated by such a system, as embodied in the Rimage Corporation (formerly IXI Corp.) Model 5661C degausser, over a volume sized for 15 inch diameter media and employing such loosely conforming windings suffers significant loss of field strength 5 inches along the axis of either coil in the direction of each axis. This system also introduces microprocessor control coupled with semiconductor switching to force a response in its two LC degaussing circuits from energy stored in another capacitor. It also employs active feedback from a magnetic sensor, although the analogous voltage or current signals might be processed simply to achieve the claimed predetermined phase and amplitude relationships that rotate its field and can allow that field to decay.
The Rimage Corp. Model UDGS-FLOOR degausser exemplifies a variation on electrically rotated transient field bulk degaussing. It features an additional coil set mutually orthogonal to both of the main coils, but wired in series with the LC circuits and switching circuit to a large capacitive energy reservoir. The field direction generated by the additional series connected coils, being orthogonal to the rotating field generated by the main coils, offers the potential of synergistic effects on erasure performance resulting from a wider range of magnetic field directions. The series connection of those coils also allows them to serve as charging reactors for the main LC circuits. Microprocessor monitoring of circuit voltages via A/D conversion in this model can time switching to force the desired phase relationship between the coil currents.

Transient magnet field degaussing system


A multi-directional swinging mechanism is disclosed. Its includes a base board, a support, a rotary member, a driving member, a swinging lever, a middle board, a retaining board and an adjuster. When the driving member drives the rotary member to rotate, the middle board and the retaining board will swing forward, backward, upward and downward. At the same time, in cooperation with the adjuster, the retaining board will also swing left and right. Therefore, an article such as a toy or a decoration positioned on the retaining board can be swung in multiple directions.

The present invention relates to a multi-directional swinging mechanism which is able to swing a toy or a decoration up and down, forward and backward and left and right.
The swinging mechanism used in the existing toy or decoration generally includes a rotary disc and a linkage assembly disposed on an eccentric position of the rotary disc. When the rotary disc is rotated, the linkage is swung back and forth along. However, such swinging movement is a two-dimensional swinging movement (up and down, forward and backward) rather than a three-dimensional one (up and down, forward and backward, left and right).


A semiconductor wafer cleaning apparatus is disclosed including a cleaning solution supply line for supplying a cleaning solution to a surface of a wafer, one end of which is connected to a cleaning solution supply source. A gas supply line is connected to a gas supply source to supply a gas to the surface of the wafer. A nozzle assembly is connected to respective second ends of the cleaning solution supply line and the gas supply line, the nozzle assembly having a spray nozzle facing the surface of the wafer, wherein the cleaning solution and gas supplied are mixed in the nozzle assembly.

1. Field of the Invention
The present invention relates to an apparatus and method of cleaning a semiconductor wafer and, more particularly, to an apparatus and method of cleaning a semiconductor wafer that is effectively removes a developer containing a photoresist from the wafer after an exposed photoresist is developed during photolithography in semiconductor device fabrication processes.
2. Discussion of the Related Art
Photolithography is used to form the pattern of a semiconductor device. Specifically, a photoresist is coated on a wafer, and a photomask is aligned above the wafer. The photoresist is then exposed through the photomask and developed using a developer, followed by removal of the developer containing the photoresist. What remains is the pattern of a semiconductor device.
A cleaning solution is used to remove the developer after the development of the photoresist. This cleaning process is carried out in such a manner that the cleaning solution is supplied to the surface of the wafer containing the developer while the wafer is rotated at a high speed, to thereby clean the developer containing the photoresist residue.
Referring to FIG. 1, a conventional wafer cleaning apparatus is constructed in such a manner that, when an air valve 14 is opened by the operation of a switching solenoid 10, deionized water (D.I. water) used as a cleaning solution flows through a D.I. water supply line 16 from a D.I. water supply source 12, and is supplied through a D.I. water outlet 18 to the surface of the wafer 20 by free fall, while the wafer rotates at a high speed.
In the aforementioned conventional wafer cleaning apparatus, D.I. water which falls on the wafer removes the developer as the D.I. water moves along the surface of the wafer toward the wafer edge due to the centrifugal force generated by the high-speed rotation of the wafer.
In this cleaning method, however, the vertical force resulting from the free fall of the D.I. water works on only that region of the wafer where the D.I. water falls directly. As a result, additional time and larger quantities of D.I. water are required in order to clean the developer left in a groove of a pattern located at a region other than the region on which the D.I. water falls.

Apparatus for cleaning semiconductor wafers


Apparatus and methods according to some embodiments of the present invention use a graphical model, such as a Markov random field model, to represent principal driving directions within an environment. The model has a plurality of nodes representing spatial locations within the environment, and the principal direction for each node is determined probabilistically using linear features detected within an image of the environment. Apparatus and methods according to embodiments of the present invention can be used in improved autonomous navigation systems, such as robotic vehicles.

Operation of autonomously navigating vehicles, such as robotic vehicles, preferably includes determination of safe and predictable routes through an environment. A human driver is generally capable of detecting principal directions within an environment, such as drivable passageways through a parking lot. However, this is a challenge for autonomous navigation systems capable of operating with human input.

Detecting principal directions of unknown environments

Toyota Motor Engineering & Manufacturing North America, Inc.


A chip package device includes an electrically conducting chip carrier, at least one semiconductor chip attached to the electrically conducting chip carrier, and an insulating laminate structure embedding the chip carrier, the at least one semiconductor chip and a passive electronic device. The passive electronic device includes a first structured electrically conducting layer, the first structured electrically conducting layer extending over a surface of the laminate structure.

The necessity to provide smaller, thinner, lighter, cheaper electronic systems with reduced power consumption, more diverse functionality and improved reliability has driven a stream of technological innovations in all technical fields involved. This is also true for the areas of assembly and packaging providing protective environment for miniaturized electronic systems and allowing for a high degree of reliability.


An acoustic resonator assembly includes a layer of high-acoustic-impedance material and a layer of low-acoustic-impedance material made of a low-electrical-permittivity material. This assembly may support the resonator over an interconnect layer or act as a decoupling assembly between two active elements of the resonator. The assembly may alternatively include three low-acoustic impedance layers. Alternatively, the assembly may include three acoustic impedance layers wherein two of the layers are low acoustic impedance layers and the third layer has a higher acoustic impedance than the first two or alternatively is a high-acoustic impedance layer.

1. Technical Field of the Invention
The present invention relates to the field of integrated circuits, and more particularly to integrated circuits comprising one or more acoustic or piezoelectric resonators. Such circuits can be used in signal processing applications, for example, for performing a filtering function.
2. Description of Related Art
Acoustic resonators are integral with the integrated circuit, while having to be acoustically or mechanically isolated therefrom. For this purpose, a support capable of producing such isolation may be provided. The support may comprise an alternation of a layer having a high acoustic impedance and a layer having a low acoustic impedance (see, U.S. Pat. No. 6,081,171, the disclosure of which is hereby incorporated by reference).
The term "acoustic impedance" is understood to mean the quantity Z given by the density ρ of the material multiplied by the acoustic velocity ν, i.e., Z=ρν. The acoustic velocity ν may be taken as being defined by:ν=(ρC33)1/2where C33 is one of the coefficients of the elastic compliance matrix.
For high acoustic isolation performance, it is desirable for the difference in acoustic impedance between the materials to be as high as possible.
A need exists in the art to meet this requirement.

Support and decoupling structure for an acoustic resonator, acoustic resonator and corresponding integrated circuit


Twisted ceiling fan blades for low, medium and high speed operation of less than approximately 250 rpm. The novel blades twisted blades can be configured for 60″ and 64″ diameter fans, and have less blades (3 for example) than conventional flat type bladed fans having 4, 5 blades and have greater air flow and less power draw results than the conventional flat 54 inch fans. Any of the novel twisted blades of 54″, 60″ and 64″ can be run at reduced speeds, drawing less Watts than conventional fans and still perform better with more air flow and less problems than conventional flat type conventional blades.

Ceiling fans have been around for many years as a useful air circulator. The popular blade style over the years is a flat planar rectangular blade that can have a slight tilt, as shown for example in U.S. Pat. Nos. Des. 355,027 to Yound and Des. 382,636 to Yang. These patents while moving air are not concerned with maximizing optimum downward airflow. Furthermore, many of the flat ceiling fan blades have problems such as poor performance at high speeds, wobbling, and excessive noise that is noticeable to persons in the vicinity of the fan blades.
Aircraft, marine and automobile engine propeller type blades have been altered over the years to shapes other than flat rectangular. See for example, U.S. Pat. Nos. 1,903,823 to Lougheed; 1,942,688 to Davis; 2,283,956 to Smith; 2,345,047 to Houghton; 2,450,440 to Mills; 4,197,057 to Hayashi; 4,325,675 to Gallot et al.; 4,411,598 to Okada; 4,416,434 to Thibert; 4,730,985 to Rothman et al. 4,794,633 to Hickey; 4,844,698 to Gornstein; 5,114,313 to Vorus; and 5,253,979 to Fradenburgh et al.; Australian Patent 19,987 to Eather. However, these patents are describing devices that are generally used for high speed water, aircraft, and automobile applications where the propellers are run at high revolutions per minute(rpm) generally in excess of 500 rpm. None of these propellers are designed for optimum airflow at low speeds of less than approximately 200 rpm which is the desired speeds used in overhead ceiling fan systems.
Some alternative blade shapes have been proposed for other types of fans. See for example, U.S. Pat. Nos. 1,506,937 to Miller; 2,682,925 to Wosik; 4,892,460 to Volk; 5,244,349 to Wang; Great Britain Patent 676,406 to Spencer; and PCT Application No. WO 92/07192.
Miller '937 requires that their blades have root "lips 26" FIG. 1 that overlap one another, and would not be practical nor useable for three or more fan blade operation for a ceiling fan. Wosik '925 describes "fan blades . . . particularly adapted to fan blades on top of cooling towers such for example as are used in oil refineries and in other industries . . . ", column 1, lines 1–5, and does not describe any use for ceiling fan applications. The Volk '460 patent by claiming to be "aerodynamically designed" requires one curved piece to be attached at one end to a conventional planar rectangular blade. Using two pieces for each blade adds extreme costs in both the manufacturing and assembly of the ceiling itself. Furthermore, the grooved connection point in the Volk devices would appear to be susceptible to separating and causing a hazard to anyone or any property beneath the ceiling fan itself. Such an added device also has necessarily less than optimal aerodynamic properties.
Wang '349 requires each of their blades be "drilled with a plurality of perforations . . . for reducing weight . . . (and) may be reinforced by at least one rib . . . ", abstract. Clearly, such a blades would not be aesthetically pleasing to the user to have various holes and ribs visible on the blades, and there is no description for increasing airflow with such an arrangement. Great Britain Patent '406 describes ". . . fan impellers" that require an ". . . unitary structure . . . constituted by a boss and four blades . . . " page 1, lines 38+, and does not describe any single blades that can be used without any central boss type hub arrangement nor any use for less than three or more than four blade operation that will allow versatility for mounting separate numbers of blades on a ceiling fan motor. PCT '192 is for use "in an electric fan . . . to convert axially existing ambient air into a radially outward current of air . . . ", abstract, and is shown in FIGS. 5–12 as being used for being mounted on "post(s)", and the like, and is not directed toward a ceiling fan operation, which would direct air primarily downward. Additionally, PCT '192 generally requires an elaborate arrangement of using plural blades angled both upward and downward for operation.
U.S. Pat. No. 6,244,821 to Boyd et al. describes a ceiling fan of covering large blades of between 15 feet(180 inches) to approximately 40 feet(480 inches) which can not be used for conventional applications such as those used in homes and offices.
U.S. Pat. Nos. 34,109 and 4,844,698 to Gornstein describes sixty inch blades for use vehicles such as hovercrafts, airboats, and dirigibles which have no application to being used as ceiling fans.
U.S. Pat. No. 5,860,788 to Sorensen mentions some old uses of having four to six blade fans that cover approximately 5 feet(60 inches) but has not no data on low speed operation, nor on using three blades, nor on using any twisted blade configurations, and would not have enhanced efficiency over conventional ceiling fan operation.
Although larger ceiling fans with diameters greater than 54 inches have been produced, these fans have not incorporated enhancements to the fan blade, such as maximizing twist, taper and air foil configurations to optimize air moving performance.
Thus, the need exists for better performing ceiling fans over the prior art.

Enhancements to high efficiency ceiling fan

Research Foundation of the University of Central Florida, Inc.


This invention relates to the field of recombinant antibody technology. It provides novel recombinant IgY antibody constructs for diagnostic and therapeutical applications. The bivalent antibody constructs display a heterotetrameric or homodimeric format stabilized by disulfide bonds. The constant heavy chain domains CH2-CH4 are partly or completely of avian origin, whereas the VH, VL, CL, and CH1 domains as well as the hinge region may be of avian origin or derived from any other species. The invention allows to combine the advantages of IgY antibodies with those of established mammalian monoclonal antibodies. IgY antibody constructs comprising nonglycosylated IgY constant heavy chain domains allow to reduce unwanted interactions with C-type lectins, e.g., in human sera. Furthermore, chimeric IgY antibody containing mammalian VH, VL, CL, and CH1 domains as well as a mammalian hinge region provide a higher molecular stability than IgY antibodies in acidic conditions and, thereby, are especially suited for peroral therapeutic applications.

Antibodies play an important role in clinical applications as well as diagnostic assays. Administration of antibodies specific to host pathogens is an attractive approach to establish protective immunity, employed in passive vaccination or in therapy. Antibodies are often used as vehicles that direct a linked moiety, e.g., an active agent or a toxin, to specific sites in the body, where the antigens recognized by the antibodies are expressed. Labelled antibodies can be used for in vivo diagnostics.
The most common application however is the in vitro diagnostic use of antibodies in immunological assays to identify and/or quantify antigens of interest. The most important formats of immunological tests are ELISA (Enyzme linked immunosorbent assay), RIA (Radioimmunosorbent assay) or ELISPOT (Enzyme linked immunospot), as well as flow cytometric tests such as FACS(Fluorescence activated cell sorting) or blots, e.g., Western blot or dot blot. Antibodies are also used in microscopic applications, such as histology, immunofluorescence or electron microscopy. Antibodies are also used in biotechnological applications, e.g., for purification of the respective antigens.
Typically, antibodies of the Immunoglobulin G (IgG) isotype are used is these applications, although antibodies of other isotypes, e.g., Immunoglobulin M (IgM), are also employed. Polyclonal antibodies are normally generated by immunization of animals, such as mice, rats, rabbits etc., and isolation of antibodies from the serum, following standard protocols. Generation of monoclonal antibodies, which only have a single antigenic specificity, by fusion of antibody-producing lymphocytes from immunized animals with myeloma cells is also well established.
However, use of such antibodies in practice also raises a number of difficulties.
Rheumatoid factor (RF) and human anti-mouse IgG antibodies (HAMA) are probably the most well known causes of false positive or false negative reactions in immunological assays (Boscato L M, Stuart M C, Clin Chem 34, 27-33, 1988). RF is an auto-antibody that reacts with the Fc part of IgG. The disease most often associated with RF is rheumatoid arthritis, but RF can be found in serum from patients with many other diseases and also in 3-5% of healthy blood donors (Johnson P M, Faulk W P, Clin Immunol Immunopathol 6, 414-430, 1976). Production of HAMA is mainly the result of therapeutic approaches with mouse monoclonal antibodies, but HAMA may also be found in serum from patients who have not been treated with antibodies. RF or HAMA may react with both the capture antibody and the detection antibody in a sandwich assay, thereby mimicking antigen activity. A reaction with the detection antibody results in formation of an immune complex which may influence the activity of the detection antibody. HAMA may also react with the antigen-binding region of the detection antibody, thereby impairing or inhibiting antigen binding. The problem of RF and HAMA interference will increase as the sensitivity of the assay increases. Interference by anti-IgG antibodies and antibody-binding substances have been demonstrated in approximately 40% of serum samples from healthy individuals in an immunoradiometric assay (Boscato L, Stuart M, Clin Chem 32, 1491-1495, 1986). RF and HAMA will also give erroneous results in nephelometry and turbidimetry as they change the size of antigen-antibody complex (Chambers R E, et al., Ann Clin Biochem 24, 520-524, 1987).
The prevalence of human anti-mammalian antibodies causing potential interferences in immunological assays varies from 1-80% in the general population (Kricka L J, Clin. Chem. 45, 942-956, 1999).
Furthermore, the IgG antibodies normally used for clinical assays, bound to a solid phase, and antigen-antibody complexes comprising such antibodies, as well as IgM antibodies, can activate the human complement system (Larsson A, Sjoquist J, J Immunol Methods 119, 103-109, 1989). Activated C4 molecules bind to the Fab region of IgG and may interfere with the antigen binding (Campbell R D, et al., Biochem J 189, 6780, 1980). Complement components may also solubilize precipitated immune complexes and prevent soluble immune complexes from precipitating (Baatrup G, et al., Scand J Immunol 23, 397-406, 1986; Miller G W, Nussenzweig V, Proc Natl Acad Sci USA 72, 418-422, 1975).
In clinical laboratories, most analyses are performed on serum samples. A newly obtained serum sample contains active complement, but the activity declines during storage and handling (Whaley, K. Methods in complement for clinical immunologists, Churchill Livingstone, 1985). Accordingly, the complement activity may vary between different patients and also between different samples from the same patient. To avoid activation of the complement cascade, EDTA is often included in tubes used for blood sampling. EDTA prevents complement activation and coagulation by sequestering calcium ions. Most of the standards and controls used have been stored and contain an inactive complement system. This difference in activity between the samples and the standards will cause erroneous results. Complement activation was shown to interfere in an immunometric TSH assay and depressed the TSH values by up to 40% (Kapyaho K, et al., Scand J Clin Lab Invest 49, 211215, 1989).
An additional problem in working with cells or tissue—or with in vivo applications—is the presence of receptors for immunoglobulins. Human FcγRI has a high affinity for monomeric IgG, while FcγRII and FcγRIII mainly bind IgG complexes. There is often some aggregated IgG formed during the purification of IgG or during the labeling procedures that will increase the binding to FcγRII and FcγRIII receptors. Interaction with Fc receptors may cause an increased background staining in immunological tissue analysis. When working with living cells, the interaction with Fc receptors may cause cell activation and changes in the expression of surface proteins. For example, it has been shown that IgG antibodies used in flow cytometry form immune complexes that cause platelet activation and changes in the expression of the GpIlb-IIIa receptor (Lindahl T L, et al., Thromb Haemost 68, 221-225, 1992; Rubinstein E, et al., Br J Haematol 78, 80-86, 1991). Immune complexes containing IgG may also stimulate the production of cytokines (van de Winkel J G, Capel P J, Immunol Today 14, 215-221, 1993).
Similarly, Staphylococcal protein A and Streptococcal protein G are Fc-binding bacterial proteins which are widely used for their ability to bind to IgG. Bacteria of the Staphylococcus aureus Cowan 1 strain and group C Streptococcus sp. are used as immunoadsorbent for IgG. Staphylococci and Streptococci are often found in bacterial samples. When present, they may bind detection antibodies with specificities for other bacteria and cause erroneous results. There are also other bacteria (e.g. Peptostreptococcus magnus, Streptococcus suis and Actinobacillus actinomycetemcomitans) with Ig-binding capabilities (Engstrom P E, et al., J Clin Periodontol 20, 746-751, 1993; Benkirane R, et al., FEMS Immunol Med Microbial 20, 121-127, 1998; Kastern W, et al., Infect Immun 58, 1217-1222, 1990).
One approach to avoid the above mentioned problems, e.g. of cross-reactivity and complement activation, is the use of antibody fragments instead of complete antibodies. For example, IgG antibodies can be enzymatically cut by papain into two Fab fragments (fragment antigen binding) and one Fc fragment (fragment cristallizable). IgG antibodies contain two light and two heavy chains. The light chains have a molecular mass of about 25 kDa and the heavy chains of about 50 kDa. The heavy chain has one variable (V) region and three constant (C) regions. The light chain is composed of one variable and one constant domain. IgG is bivalent, i.e. it has two antigen binding sites. These are composed of the variable domains of both heavy and light chains. The hinge region between the two "arms" of the antibody and the "stem" region gives flexibility to the molecule. Fab fragments thus carry one antigen binding site (they are monovalent).
Recombinant production of Fab fragments is possible. In a preferred form, light and heavy chain domains are formed by a single peptide chain, which can be recombinantly generated (scFv, single chain fragment variable). Libraries of scFv, in particular as phage display libraries, are available in the art, which facilitate generation of recombinant antibodies or scFv specific for a given antigen.
One major limitation of scFv or Fab molecules, however, is their monovalent format, impairing the affinity of these molecules and, thereby, their applicability for therapeutic and diagnostic applications. Utilizing short linker sequences for the construction of scFv, formation of scFv dimers can be favored (Holliger P, et al., Pro. Natl Acad Sci USA 90, 6444, 1993). However, such dimers ('diabodies') are formed by noncovalent association and may dissociate. Alternatively, bivalent Fab2 fragments can be used, which still contain the hinge region, wherein the two heavy chains are connected by a disulfide linkage. Fab2 can be produced by enzymatic digestion of antibodies with pepsin.
However, especially for diagnostic applications, another major limitation of scFv, Fab and Fab2 molecules is the lacking Fc region. As a result, many of the advantages offered by antibodies for immunological detection procedures, such as recognition by secondary antibodies to the Fc region, cannot be realized.
The person skilled in the art is therefore faced with the need of generating improved antibodies that avoid or minimize the above mentioned problems in the use of complete IgG antibodies, e.g. of cross-reactivity and complement activation that can lead to false-positive and -negative results in diagnostic assays, but further do not show the disadvantages brought about by use of scFv, Fab and Fab2 molecules.

Bivalent IgY antibody constructs for diagnostic and therapeutic applications


Multi-destination frames in a network fabric may be carried in IP multicast packets. As such, the network fabric may us IP multicast technique such as a PIM protocol for handling the multi-destination frames. To provide redundancy, the system administrator can use phantom rendezvous points (RPs) that include multiple physical RPs where one of the RPs serves as a primary RP and the other RPs serve as secondary RPs (e.g., backup RPs). Instead of the system administrator manually configuring the phantom RPs, the RPs are automatically configured. To do so, the system administrator may use a GUI to provide multicast groups allocated for the multi-destination traffic, the number of desired phantom RPs (or physical RPs), and the desired RP redundancy. Based on these parameters, a data center manager generates one or more templates that automatically configure the network devices in the fabric as they are booted.

Bidirectional Protocol Independent Multicast (Bidir PIM) is a member of the suite of multicast routing protocols which also includes dense-mode, sparse-mode, and source specific multicast (SSM). Bidir PIM was developed to help deploy emerging communication and financial applications that rely on a many-to-many applications model. Bidir PIM allows these applications to easily scale to a very large number of groups and sources by eliminating the maintenance of source states.
Traditional PIM protocols (dense-mode and sparse-mode) provided two models for forwarding multicast packets: source trees, and shared trees. Source trees are rooted at the source of the traffic while shared trees are rooted at the rendezvous point. Each model has its own set of characteristics and can be optimized for different types of applications. The source tree model provides optimum routing in the network, while shared trees provide a more scalable solution. Source trees achieve the optimum path between each receiver (or recipient) and the source at the expense of additional routing information such as a routing entry per source in the multicast routing table. This is acceptable in applications with a limited number of sources. Applications like live broadcasts and distance learning are some examples where only one or a few sources are active. On the other hand, the shared tree provides a single distribution tree for all of the active sources. This means that traffic from different sources traverse the same distribution tree to reach the interested receivers, thereby reducing the amount of routing states in the network. Bidir PIM (a variant of PIM sparse-mode) uses these shared trees as its main forwarding mechanism.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.

Managing rendezvous point redundancy in a dynamic fabric network architecture


An image forming apparatus including a photosensitive bodies fixing unit. The image forming apparatus includes: a main body frame; a fixing frame on which a plurality of photosensitive bodies are installed, the fixing frame being fixed at a predetermined position on the main body frame; a guide protruding portion formed on the fixing frame to guide the fixing frame to be coupled with the main body frame; a guide rail formed on the main body frame for the guide protruding portion to be inserted into; and a position determining portion formed on the guide rail to fix the guide protruding portion to a predetermined position. Accordingly, the parallel alignment between the scanning units and the photosensitive bodies may be relatively easily maintained and accurate color overlapping and color presentation are obtained to achieve high image quality. Further, the fixing frame may be fixed at a predetermined position by adjusting the tolerance of a part of the position determining portion, and the transfer unit may be integrated with the fixing frame and fixed at a predetermined position on the main body frame.

1. Field of the Invention
An aspect of the present invention relates to an image forming apparatus, and, more particularly, to an image forming apparatus including a plurality of photosensitive bodies, scanning units, and a photosensitive body fixing apparatus, in which the photosensitive body fixing apparatus allows assembly tolerances such as the parallel alignment between the photosensitive bodies and the scanning units to be easily adjusted and high image quality may be obtained.
2. Description of the Related Art
An electrophotographic image forming apparatus produces a monochrome image or a color image by forming an electrostatic latent image on a photosensitive body charged to a uniform electrostatic potential by scanning a laser on the photosensitive body, developing the latent image by supplying toner of a predetermined color to the photosensitive body, and transferring and fusing the image to a sheet of paper.
In general, an electrophotographic color image forming apparatus includes one or more scanning units that scan light onto a photosensitive body on which an electrostatic latent image is to be formed, a plurality of developing units that contain toner of different colors, a transferring unit that transfers a developed toner image to a sheet of paper, and a feeding unit that contains and feeds sheets of paper.
Each of the developing units for each color is installed at a predetermined position along a guide surface formed on a main body frame of the image forming apparatus. Each of the scanning units is either assembled into the main body frame or assembled into an individual frame and then integrally installed in the main body frame while being kept parallel to a plurality of photosensitive bodies. The positions of the respective photosensitive bodies may be selected as reference points in assembling the plurality of developing units and scanning units.
When the units are installed in the main body frame, the positions of the developing units, the scanning units and the photosensitive bodies between the scanning units and the developing units must be strictly controlled so as to provide for accurate color overlapping, uniform color representation, and to avoid color banding.
Meanwhile, if each of a plurality of photosensitive bodies is fixed individually to the main body frame, managing assembly tolerances such as the distance between the photosensitive bodies, the parallel alignment between the scanning units and the photosensitive bodies, and the focal length of the light may be difficult. Further, when each of the plurality of photosensitive bodies is removed individually from the main body frame for maintenance, the photosensitive body must be installed at/separated from a predetermined position regardless of the proficiency of an operator or the presence of an assembly jig.

Image forming apparatus including photosensitive body fixing apparatus


Embodiments of the disclosure include a combustor assembly. The combustor assembly may include one or more fuel plenums. The combustor assembly may also include one or more fuel distribution plates disposed within the fuel plenums. Moreover, the combustor assembly may include a number of mixing tubes disposed at least partially within the fuel plenums and extending through the fuel distribution plates. In certain aspects, the mixing tubes may each include a reduced diameter about the fuel distribution plates to form an annulus therebetween.

In a conventional gas turbine, numerous combustors are disposed in an annular array about the axis of the gas turbine. A compressor supplies compressed air to each combustor, wherein the compressed air and fuel are mixed and burned. Hot combustion gases may flow from each combustor through a transition piece to a first stage nozzle to drive a turbine and generate power. Often, each combustor includes a fuel plenum or each nozzle in the combustor has a fuel plenum with multiple nozzles per combustor disposed therein. Typically, the fuel plenum may include various components that are machined separately and thereafter assembled. Current fuel plenum assemblies and manufacturing techniques, however, tend to produce misaligned components and/or components that must be machined with increased tolerances to ensure that they fit together, leading to increased manufacturing costs, stress on the components, and/or inefficient operation. Accordingly, improving fuel plenum assemblies and the associated manufacturing techniques continues to be a priority.


A duplex printer with a small, compact conveyance path has a medium supply path and a medium inverting path that merge into a middle conveyance path at a junction. The middle conveyance path goes to a path switching unit connecting a main conveyance path and the inverting path. A flap, which is a path switching member, is disposed in the path switching unit. A middle conveyance roller pair, having a middle conveyance roller and a nipping portion, conveys the medium (e.g. paper) through the middle conveyance path. The portion of the middle conveyance path from at least the junction to the nipping portion is a conveyance path portion defined by the roller surface of the middle conveyance roller. The paper fed to the middle conveyance path is guided by the middle conveyance roller from the junction to the nipping portion of the middle conveyance roller pair.

1. Technical Field
The present invention relates to a printer having an inverting path that reverses the front and back sides of recording paper or other sheet media and then feeds the inverted media back into the printing path.
This application is based upon Japan Patent Appl. Pub. No. 2014-040163 filed on Mar. 3, 2014, and Japan Patent Appl. Pub. No. 2014-168235 filed on Aug. 21, 2014, the entire contents of which are incorporated by reference herein.
2. Related Art
Examples of printers with an inverting path are printers with an automatic duplex print function such as described in Japan Patent 3847149 and JP-A-2013-241278. These printers have a supply path that conveys recording paper to be printed on from a supply unit, a main conveyance path passing where the recording paper is printed on, and an inverting path that reverses the front and back sides of the paper after printing on the first side. A diverter for switching the conveyance path is disposed between the upstream end of the main conveyance path and the upstream end of the inverting path. The supply path and the inverting path merge at the downstream ends thereof and then connect to where the diverter is disposed. The recording paper is guided from the supply path or the inverting path to the main conveyance path by the diverter, and the recording paper is guided to the inverting path after the first side is printed on the main conveyance path.
In the printer described in JP-A-2013-241278, a second supply roller is disposed as a conveyance roller in the supply path. The recording paper supplied from the supply unit is conveyed by the second supply roller toward the main conveyance path, and is then passed to the main conveyance roller disposed to the main conveyance path. Even recording paper that is short in the conveyance direction can be conveyed by the second supply roller.
In the printers with an inverting path as described in Japan Patent 3847149 and JP-A-2013-241278, a path switching unit comprising the diverter and the merging portion with the downstream end of the inverting path is disposed to the conveyance path between the supply unit and the print position on the main conveyance path. The length of the conveyance path from the supply unit to the print position therefore increases. A conveyance roller such as described in JP-A-2013-241278 may also be required to print on short recording paper. Making a printer with an inverting path such as described above small and compact is therefore difficult because the conveyance path is long and a conveyance roller for conveying short recording paper is required.
Because the supply path and the inverting path merge together, there can be a difference in elevation or a discontinuity between the conveyance guide surfaces of the conveyance paths where they merge. The recording paper can therefore easily jam where the conveyance paths merge. More specifically, because the leading end part of the recording paper can easily curl after printing on the first side, the recording paper may jam where the conveyance paths merge after printing the first side. Problems such as deviation in the conveyance precision of the recording paper where the paths merge can also result from the difference in elevation or discontinuity between the conveyance guide surfaces.