A system and method for permitting variable information rates and improved error performance using orthogonal or near-orthogonal codes is disclosed. This is achieved by simultaneously transmitting two or more Walsh code words from a given orthogonal code set and/or by transmitting multiple shorter orthogonal codewords sequentially such that their combined length equals the original codeword. It should be emphasized that the present invention can be used with any orthogonal or near-orthogonal code set.

1. Technical Field of the Invention
The invention relates to the field of telecommunications and more particularly, to a system and method for providing variable user information rates and for improving performance and bandwidth utilization in telecommunications systems using orthogonal codes for error control.
2. Description of Related Art
The cellular telephone industry has made phenomenal strides in commercial operations throughout the world. Growth in major metropolitan areas has far exceeded expectations and is outstripping system capacity. If this trend continues, the effects of rapid growth will soon reach even the smallest markets. The predominant problem with respect to continued growth is that the customer base is expanding while the amount of electromagnetic spectrum allocated to cellular service providers for use in carrying radio frequency communications remains limited. Innovative solutions are required to meet these increasing capacity needs in the limited available spectrum as well as to maintain high quality service and avoid rising prices.
Currently, channel access is primarily achieved using Frequency Division Multiple Access (FDMA) and Time Division Multiple Access (TDMA) methods. In FDMA systems, a physical communication channel comprises a single radio frequency band into which the transmission power of a signal is concentrated. In TDMA systems, a physical communications channel comprises a time slot in a periodic train of time intervals transmitted over the same radio frequency. Usual methods of implementing a TDMA system incorporate FDMA as well.
Spread spectrum comprises a communications technique that is finding commercial application as a new channel access method in wireless communications. Rudimentary spread spectrum systems have been around since the days of World War II. Early applications were predominantly military-oriented (relating to smart jamming and radar). However, there is an increasing interest today in using spread spectrum systems in communications applications, including digital cellular radio, land mobile radio, and indoor/outdoor personal communication networks.
Spread spectrum operates quite differently from conventional TDMA and FDMA communications systems. In a direct sequence code division multiple access (DS-CDMA) spread spectrum transmitter, for example, a digital symbol stream for a given dedicated or common channel at a basic symbol rate is spread to a xe2x80x9cchipxe2x80x9d rate. This spreading operation involves applying a spreading code that is channel-unique (sometimes referred to as a xe2x80x9csignature sequencexe2x80x9d) to the symbol stream that increases its transmission rate (as well as the bandwidth requirement) while adding redundancy. Typically, the digital symbol stream is multiplied by the unique digital code during spreading. The intermediate signal comprising the resulting data sequences (chips) is then summed with other similarly processed (i.e., spread) intermediate signals relating to other (dedicated or common) channels.
A scrambling code that is unique to a base station (often referred to as a xe2x80x9clong codexe2x80x9d since in most cases it is longer than the spreading code) is then applied to the summed intermediate signals to generate an output signal for multi-channel transmission over a communications medium. The intermediate signals derived from the various dedicated or common channels thus advantageously share one transmission communications frequency band, with the multiple signals appearing to be located on top of each other in both the frequency domain as well as the time domain. Because the applied spreading codes are unique to each channel, however, each intermediate signal that is transmitted over the shared communications frequency is similarly unique, and may be distinguished from others through the application of proper processing techniques at the receiver end.
In the DS-CDMA spread spectrum mobile station (receiver), the received signals are recovered by applying (i.e., multiplying, or matching) the appropriate scrambling and spreading codes to despread, or remove the coding from the desired transmitted signal and return to the basic symbol rate. Where the spreading code is applied to other transmitted and received intermediate signals, however, only noise is produced. The despreading operation thus effectively comprises a correlation process comparing the received signal with the appropriate digital code to recover the desired information from the channel.
Orthogonal codes or near-orthogonal codes (i.e., codes having relative high relative auto-correlation and low relative cross-correlation values) are used for error control in telecommunications systems. Walsh codes are one example of an orthogonal code. In a coding scheme using Walsh codes, a k-bit information word (xe2x80x9cinfowordxe2x80x9d) is converted into a 2k-bit sequence using the Hadamard transform. Such a conversion will be referred to in this patent application as a (2k,k) orthogonal code. A Walsh code for encoding a 2-bit information sequence to a 4-bit orthogonal codeword is shown below:       H    4    =      "LeftBracketingBar"                            1                          1                          1                          1                                                  -            1                                    1                                      -            1                                    1                                      1                          1                                      -            1                                                -            1                                                1                                      -            1                                                -            1                                    1                      "RightBracketingBar"
Here, the four rows of the matrix H4 form the code words for the four information symbol sequences whose binary values are equal to the numeric values of the four row indices. For example, the information sequences (0,0), (0,1), (1,0) and (1,1) would be mapped to the codewords (1,1,1,1), (1,xe2x88x921,1,xe2x88x921), (1,1,xe2x88x921,xe2x88x921) and (1,xe2x88x921,xe2x88x921,1) respectively. The Fast Hadamard Transform is then used to demodulate the incoming signal non-coherently. The Fast Hadamard Transform acts as a correlator, and those code-word(s) (or component(s) thereof) that have the highest correlation values can then be identified as the transmitted code-word(s). The uniqueness of the mapping between the 2-bit information sequences and the 4-symbol code words (in the example above) allows the unambiguous detection and decoding of the transmitted symbols.
The use of the Walsh-Hadamard codes described above result in a bandwidth expansion of 2k/k (i.e., a k-bit information word expands to a 2k-bit code word) which is quite high. The inverse of the bandwidth expansion is referred to as the coding rate. Consequently, these Walsh-Hadamard codes are normally used in very low signal-to-noise ratio environments. For example, the IS-95 CDMA system compensates the low signal-to-interference ratios in the system through the use of such codes. Another application for such schemes is in random access protocols for cellular and mobile satellite systems, where users may be trying to initially synchronize to the system, or attempting to originate a call or answer an incoming call.
It has been found desirable to find new techniques to improve the coding rate in a telecommunications system employing orthogonal codes. It has further been found desirable to find techniques for reducing the bandwidth expansion. An ideal telecommunications system employing orthogonal codes would thus have only that bandwidth expansion that is necessary to separate the multiple transmissions from various users without reducing the efficiency of spectrum utilization by too large a factor.
It is therefore a primary object of the present invention to provide improved performance in telecommunications systems using orthogonal codes for error control. It is a further object of the present invention to reduce bandwidth expansion in such telecommunications systems. It is also an object of the present invention to improve the coding rate in a telecommunications system employing orthogonal codes.
Orthogonal codes or near-orthogonal codes (i.e., codes having high relative auto-correlation and low relative cross-correlation values) are used for error control in communication systems. For example, the IS-95 CDMA cellular standard uses a (64,6) orthogonal Walsh code on the reverse link (i.e., the link from the mobile station to the base station) for error control. As noted earlier, such a set of Walsh codes converts each 6-bit information word into a 64-symbol code word in such a way that each of the sixty-four such 64-symbol codes are orthogonal relative to each other.
The present invention allows variable transmission rates and/or improved error performance to be provided to users in conjunction with the use of orthogonal or near-orthogonal codes. In one embodiment of the present invention, this is achieved by the parallel (i.e., simultaneous) transmission of multiple codewords each of which represents a different information sequence. In an alternative embodiment, multiple shorter orthogonal codewords with higher coding rates are transmitted sequentially (one after the other) such that their combined length is the same as the original codeword. In an extension of the present invention, these two methods are combined to transmit sets of shorter codewords both simultaneously and sequentially.
When multiple codewords are transmitted simultaneously, the associated decoder needs to be able to determine the relative sequence of the codewords being transmitted simultaneously. In the preferred embodiment of the present invention, part of the information sequence being encoded is used for this purpose. The receiver decodes the transmitted codewords by selecting those codewords that have the highest correlation values with the received sequence.
It should be noted that orthogonal or near-orthogonal codes are used in some concatenated coding schemes. For example, the IS-95 CDMA standard specifies a concatenated coding scheme where a convolutional code having a rate of 1/3 and a constraint length of 9 is followed by a repetition code and a (64,6) Walsh code. In this IS-95 standard, the convolutional code is called the outer code while the Walsh code is called the inner code. In a system with concatenated coding where orthogonal or near-orthogonal codes are used as the inner code, the transmission of multiple codewords (both simultaneously and sequentially) can be used to increase the redundancy of the outer code and possibly improve the error performance of the overall coding scheme while maintaining the same overall bandwidth expansion. In this manner, the system and method of the present invention can be used to provide variable transmission rates and possibly improve error performance for a system using concatenated coding.
The present invention aims at allowing variable information rates or improved error performance with orthogonal or near-orthogonal coding through better bandwidth utilization. This is achieved by simultaneously transmitting two or more code words from a given orthogonal code set and/or by transmitting multiple shorter orthogonal codewords sequentially such that their combined length equals the longer codeword. It should be emphasized that the present invention can be used with any orthogonal or near-orthogonal code set.
The system and method of the present invention may be used in a variety of applications, e.g., in wireless communication systems, cellular radio, satellite communications, simulcast transmission, land mobile radio and cellular systems, etc. The use of the techniques detailed in the present application permits an increase in the information rate without a concomitant increase in the bandwidth requirement. This increased information rate can be used to provide variable information rates to users.
In one aspect the present invention is a system and method for improving the coding efficiency and bandwidth utilization of a Code Division Multiple Access (CDMA) transmission channel. The technique of the present invention permits the efficient encoding and transmission of an original information word having 2k bits by splitting the original information word into two equal parts having k bits each.
One part of the original information word is extended with a single bit having the value zero. The other part of the original information word is extended with a single bit having the value one. The extension of the halfwords can be done by prefixing or suffixing the additional bit to the halfword or by inserting the additional bit into the halfword.
The k+1 bits of the two extended halfwords are then encoded using a (2k+1,k+1) Walsh code to obtain two corresponding Walsh codewords, each having 2k+1 symbols. The two Walsh codewords are summed to obtain a composite Walsh codeword having 2k+1 symbols. The composite Walsh codeword having 2k+1 symbols is then optionally modulated and transmitted over an air interface. If the composite Walsh codeword having 2k+1 symbols is modulated and transmitted over an air interface, in another aspect of the present invention this transmission is received over an air interface and demodulated to recover the pair of composite Walsh codeword each having 2k+1 symbols.
In another aspect, the system and method of the present invention also presents a technique for decoding a demodulated composite Walsh codeword received over a Code Division Multiple Access (CDMA) transmission channel. In this aspect, a received composite Walsh codeword is first decomposed into its component Walsh codewords using the Fast Hadamard Transform. Each of the component Walsh codewords is then decoded to obtain associated information halfwords.
The decoded information halfwords are sorted into two lists based upon the value of an index bit at a specific position in the halfword being either zero or one. The decoded information halfwords are then further sorted in decreasing order of correlation between the Walsh codeword associated with the halfword and the composite Walsh codeword received. The index bit is then deleted from the two information halfwords having the highest correlation values to obtain two corresponding data halfwords. The two data halfwords are then concatenated in a specific order to recover the original information word that was transmitted.
In another aspect, the system and method of the present invention can be generalized to the simultaneous transmission of multiple encoded information partwords. In this aspect, an original information word having M times K bits of binary information is split into M information partwords having K bits each. Each of the M information partwords is concatenated or combined with N index bits, where N is at least equal to ┌log2 M┐.
In the preferred embodiment of the present invention, the index bits for the mth information partword are the binary representation of mxe2x88x921. As before, the N index bits can be prefixed, suffixed or intermixed with the K bits of the information partword. The K+N bits of the M extended information partwords are then encoded using a (2K+N, K+N) Walsh code to obtain a group of M Walsh codewords, each having 2K+N symbols. The M Walsh codewords are then summed to obtain a summed Walsh codeword with 2K+N symbols that is optionally modulated and transmitted over a broadcast channel.
The associated decoder of the present invention first demodulates a composite Walsh codeword received over a Code Division Multiple Access (CDMA) transmission channel. The received composite Walsh codeword of length 2K+N symbols is next decomposed into M lists of component Walsh codewords having 2K+N symbols each using the Fast Hadamard Transform. Each of the M lists of component Walsh codewords is then decoded to obtain M lists of information partwords each of which is K+N bits in length.
The components of the M lists of decoded information partwords are chosen based upon the binary value contained in the N index bits of the partwords. Each of the M lists of decoded information partwords is sorted by decreasing value of correlation between the Walsh codeword associated with a partword and the received composite Walsh codeword.
The highest ranking partword is next selected from each of the M lists and these M selected partwords are then converted into M data partwords of K bits each by deleting the N index bits from each of the partwords. Finally, the M data partwords are assembled in a specific order using the index bits to recover the original information word.
In a further embodiment of the present invention, an original information word having M times K bits of binary information is split into M information partwords having, on average, K bits each (i.e., Mxc2x7K=k1+k2+ . . . +km). Each of the M information partwords is combined with N index bits, where N is at least equal to ┌log2 M┐. The rest of the coding and decoding process for this embodiment of the invention is the same as for the earlier case where the M information partwords were of equal length.
In yet another aspect, the present invention discloses a system and method for encoding an original information word having └log2 (22kxe2x88x921+2Kxe2x88x921)┘ bits of binary information. In this aspect, a set of extended Walsh codes 2K symbols in length is created first. The extended Walsh code set includes all single Walsh codewords having 2K symbols and all combinations of two 2K-symbol Walsh codewords.
Each distinct information word is mapped to either a simple codeword or to a combination of two codewords from the extended Walsh code set. If the information codeword is mapped to a simple Walsh codeword, the simple codeword is modulated and transmitted. If the information codeword is mapped to a combination of two Walsh codewords, the two Walsh codewords are summed, modulated and transmitted in parallel. All transmitted codewords are buffered as appropriate to obtain a uniformly framed Walsh codeword 2K symbols in length.
The associated decoder of the present invention first demodulates the composite Walsh codeword received over a telecommunications channel employing orthogonal codes. A threshold value is first specified that sets the maximum acceptable difference in the correlation values of received Walsh codeword pairs.
The received composite codeword of length 2k symbols is decomposed into one or more component Walsh codewords having 2K symbols each using the Fast Hadamard Transform. The component Walsh codewords are sorted in decreasing order of correlation between the component codewords and the composite Walsh codeword.
The two highest ranking component codewords are selected from the list if the difference between their correlation values is less than the specified threshold value. On the other hand, if the difference between the correlation values of the two highest ranking component codewords is more than the specified threshold value, then only the highest ranking component Walsh codewords is selected for decoding. Finally, a mapping table is used to look up the information word that is associated with the selected Walsh codeword(s).
In another aspect of the present invention, an information word having 2K bits is serially encoded by splitting the information word into a first part having K+M bits and a second part having Kxe2x88x92M bits. The K+M bits of the first part of the information word are encoded using a (2K+M,K+M) Walsh code to obtain a first Walsh codeword having 2K+M symbols. The Kxe2x88x92M bits of the second part of the information word are encoded using a (2Kxe2x88x92M,Kxe2x88x92M) Walsh code to obtain a second Walsh codeword having 2Kxe2x88x92M symbols. The two Walsh codewords are then concatenated to obtain an extended Walsh codeword with 2K+M+2Kxe2x88x92M symbols. This extended Walsh codeword is then modulated and transmitted over an air interface.
The decoder associated with the above encoding scheme first demodulates the composite Walsh codeword received over a telecommunications channel employing orthogonal codes to yield a concatenated Walsh codeword that comprises two sequentially transmitted Walsh codewordsxe2x80x94one 2K+M symbols in length and the other 2Kxe2x88x92M symbols in length. This received Walsh codeword frame is first split into its pair of component Walsh codewords (of length 2k+M and 2kxe2x88x92M symbols).
The pair of component Walsh codewords are next translated into a pair of information partwords having K+M bit and a Kxe2x88x92M bit using the Fast Hadamard Transform. The pair of translated information partwords are then reassembled in a prespecified order (such as in the order in which they were received) to recover the original information word having 2K bits.
In a further embodiment of the present invention, an original information word having M times K bits of binary information is split into M information partwords having, on average, K bits each (i.e., Mxc2x7K=k1+k2+ . . . +km). Each of the M information partwords is combined with N index bits, where N is at least equal to ┌log2 M┐. These M extended (and possibly unequal) partwords are then sequentially transmitted as M Walsh codewordsxe2x80x94of length 2k, 2k2, . . . 2km symbols. The rest of the coding and decoding process for this embodiment of the invention is similar to the case where the sequentially transmitted partitions are equal in length.
A simplified decoder associated with the same encoding scheme first demodulates the composite Walsh codeword received over a telecommunications channel employing orthogonal codes to yield a concatenated Walsh codeword that comprises M sequentially transmitted Walsh codewords each 2K symbols in length. This received Walsh codeword frame is first split into M component Walsh codewords each having 2K symbols.
Each of the M component Walsh codewords are then translated into a K-bit information partword using a mapping table. Each of the M translated information partwords are then reassembled in the order in which they were received to recover the original information word having K times M bits.

System and method for coding in a telecommunications environment using orthogonal and near-orthogonal codes


The present invention provides an automatic process counter that detects electrical signals from fasteners and attachments fastened to devices in a hard disk drive manufacturing line and uses the signals to increment the count of the fastens. Count signals are then transmitted to a plurality of display units for visual display to monitoring operators in the manufacturing line.

In many processing and computing systems, magnetic data storage devices, such as disk drives are utilized for storing data. A typical disk drive includes a spindle motor having a rotor for rotating one or more data disks having data storage surfaces, and an actuator for moving a head carrier arm that supports transducer (read/write) heads, radially across the data disks to write data to or read data from concentric data tracks on the data disk.
In the manufacturing of the disk drive, many processes are utilized to manufacture components. Over the years, manufacturing processes have become more automated. Where repeated processes are required, such as machining, fastening or riveting, the use of automation has enhanced productivity and improved quality control by greatly reducing human error in the manufacturing process. However, in many cases, manual control is often necessary to initiate or terminate a process to change out tooling and equipment.
Standardization of repeat operations is a primary feature of automation, though automation of manufacturing processes may take many forms and can be done at almost any phase of the process, from fabrication to inspection and packaging of a completed product. In true automation, the process or step being automated involves a sensing system for making decision about device or process and then a control system that reacts to the sensed information and provides control reaction.
Manufacturing systems are also becoming more integrated. Workers involved in the manufacturing process, by controlling and operating the machinery on the assembly floor are gaining greater efficiencies. However, despite these improvements, deficiencies are still encountered, especially in the manufacturing of small components requiring several fastening processes. The miniaturization of these components leaves the counting of, for example, fasteners to the operator. This contributes to errors and disruption in the assembly line when these errors have to be fixed.
Therefore, what is need is a flexible way of fastening components and automatically counting the fastener during the fabrication and manufacturing of hard disk drives by providing a wider visibility of the counting and alarm indicators to a larger group of operators in the assembly environment.

Hitachi Global Storage Technologies, Netherlands B.V.


Systems and methods provide for reducing power draw in an autonomous vehicle. A level of sunlight can be received based on an amount of light captured by one or more sensors. The level of sunlight can be mapped to a geographical area to generate a map of shaded areas, and based on a temperature within the autonomous vehicle being outside a temperature range, the autonomous vehicle can be routed based on the map of shaded areas to bring the autonomous vehicle within the temperature range.

An autonomous vehicle is a motorized vehicle that can navigate without a human driver. An exemplary autonomous vehicle includes a plurality of sensor systems, such as, but not limited to, a camera sensor system, a lidar sensor system, a radar sensor system, amongst others, wherein the autonomous vehicle operates based upon sensor signals output by the sensor systems. Specifically, the sensor signals are provided to an internal computing system in communication with the plurality of sensor systems, wherein a processor executes instructions based upon the sensor signals to control a mechanical system of the autonomous vehicle, such as a vehicle propulsion system, a braking system, or a steering system.
Autonomous vehicles can be operated within a fleet of vehicles. Since autonomous vehicles can be electric, requiring the autonomous vehicles to be charged, any kind of charging infrastructure could be benefited by saving power draw during the autonomous vehicle's operation. Reducing power draw, such as power devoted to heating and air conditioning systems, can have cascading effects across the entire fleet.

Reducing HVAC loads for rideshare vehicles


A method, system, apparatus, or computer program product is presented for morphing a honeypot system on a dynamic and configurable basis. The morphing honeypot emulates a variety of services while falsely presenting information about potential vulnerabilities within the system that supports the honeypot. The morphing honeypot has the ability to dynamically change its personality or displayed characteristics using a variety of algorithms and a database of known operating system and service vulnerabilities. The morphing honeypot's personality can be changed on a timed or scheduled basis, on the basis of activity that is generated by the presented honeypot personality, or on some other basis. The morphing honeypot can also be integrated with intrusion detection systems and other types of computer security incident recognition systems to correlate its personality with detected nefarious activities.

1. Field of the Invention
The present invention relates to an improved data processing system and, in particular, to a method and apparatus for computer security.
2. Description of Related Art
The connectivity of the Internet provides malicious users with the ability to probe data processing systems and to launch attacks against computer networks around the world. While computer security tools provide defensive mechanisms for limiting the ability of malicious users to cause harm to a computer system, computer administrators are legally limited in their ability to employ offensive mechanisms. Although an intrusion detection system can alert an administrator to suspicious activity so that the administrator can take actions to track the suspicious activity and to modify systems and networks to prevent security breaches, these systems can typically only gather information about possible security incidents.
Honeypots have been developed as a tool to help computer security analysts and administrators in coping to a small degree with malicious computer activity. A honeypot has been defined as a resource that has value in being probed, attacked, or compromised. A resource may be an application, an object, a document, a page, a file, other data, executable code, other computational resource, or some other type of communication-type resource. For example, a honeypot may comprise a network of servers; a honeypot server is sometimes called a decoy server.
A typical honeypot is a computer server that has limited or no production value; in other words, a typical honeypot performs no significant work within an enterprise other than monitoring for activity. Since the honeypot has no significant production value, its significant value lies in the fact that it acts as a decoy to lure malicious users or hackers to probing or attacking it. In the meantime, it is hoped that a malicious user would ignore production systems that have true value within an enterprise. In addition, the honeypot collects information about probes or attacks. From this perspective, a honeypot provides a tool with a small offensive capability. Ideally, the honeypot maintains a malicious user's interest so that significant information can be gathered about the methods of operation of the malicious user and whether any computer security flaws are discovered that require immediate administrative attention.
Preventive measures are usually taken so that a malicious user does not discover the true nature of the honeypot; otherwise, the malicious user would ignore the honeypot and begin probing other systems. For example, steps are usually taken to hide any administrative information within a computer network about the existence of a honeypot so that a malicious user does not capture and read about the configuration of a honeypot, e.g., activity logs or special file names. Hence, it is common practice to configure honeypots as relatively simple systems with little activity so that sophisticated, malicious users do not detect any activity that might lead this type of user to suspect that a system that is being probed is a honeypot. For this reason, honeypots are typically taken offline to be administratively analyzed and manually reconfigured. While providing some utility, a typical honeypot remains a passive tool with limited utility.
Therefore, it would be advantageous to employ a honeypot in a more offensive role for assisting a system administrator in detecting malicious activity. It would be particularly advantageous to correlate the use of a honeypot with the use of computer security incident recognition systems and applications.

Method and system for morphing honeypot with computer security incident correlation

International Business Machines Corporation


A device for verifying the shade of a patient's teeth for the fabrication of a dental restorative comprising a mold section and a section for holding a shade tab, both of which are disposed on the shaft or rod of the device. A shade tab is formed in the mold section by applying composite material in the mold and curing it. The composite material is selected by the dentist based on the shade of the patient's teeth. After the composite material is cured, the resultant shade tab is removed from the mold and placed in the holder for the shade tab. This enables a dentist to effectively match the shade of a patient's teeth in order to provide a restoration that matches the patient's teeth.

Over the years, dentists have had the ability to restore the exposed surfaces of patients'teeth with material which quite accurately duplicates each patient's tooth anatomy so as to present a repair or restoration which visually blends with the rest of the patient's natural teeth. The restorative material is generally a photocurable or hardenable resin or composite material.
The uncured resin or paste material, once selected, is applied to a patient's tooth surface and an appropriate light source is directed at the surface to cure and harden the material in a very short time period.
One of the major drawbacks to such repair resides in the accurate selection of the color or shade of the restorative material. A number of suppliers provide restorative materials in a broad variety of shades for selection by the dentist. Accompanying each restorative material kit is typically a color sample which includes a plurality of plastic pieces each having a shape similar to a human tooth and each having a different shade which is intended to represent the color of each particular material by code or name designation.
In practice, however, the majority, if not all of the associated samples provided by the manufacturers of each restorative material do not accurately reflect the true shade of the material which correlates with the sample provided. Further, in most, if not all cases, the shade samples provided by the manufacturers are fabricated or molded of a plastic material which is not identical in content or in consistency to the restorative material itself.
Furthermore, the shade samples offered by manufacturers are designed to be used for the lifetime of the material system and are subject to repeated use by a dentist. The samples are required to be sanitized between usage, which can be quite burdensome.
In any event, the dentist utilizing the restorative material is at a serious disadvantage when attempting to select a restorative material which identically matches a particular patient's tooth or teeth to be repaired. The dentist must compare the samples provided with the coloration of the patient's teeth and then make the selection accordingly. However, many times there are inconsistencies in the coloration of the samples provided and the actual restorative material. As a result, the finished dental product typically does not identically match the rest of the patient's original teeth.
It is therefore desirable to provide a method whereby a dentist can easily match the shade of the dental restorative material to the patient's teeth. It is further desirable to provide disposable shade verifying devices. It would be beneficial to provide shade tabs that accurately match the shade of a patient's teeth.

Device for determining shades of dental restorations


A circuit board with a lateral conductive pattern and shielded regions comprises a first contour cut laminate of a substrate having a conductive pattern of signal conductors and ground conductors on one side and a copper foil on the other side, covering the entire side. This laminate is laminated with the side provided with the conductive pattern to a second laminate also comprising a contour cut substrate and a copper foil provided on the substrate on the side opposite to the first laminate. Windows are cut in the substrate of the second laminate and are etched away in the top copper foil to enable mounting of components to the conductive pattern in the windows. A metal layer is provided to electrically connect said foil covering the entire other side of the first laminate with the ground conductors of the conductive pattern and the foil of the second laminate. In a method of manufacturing such a circuit board a first laminate of a substrate, covered on one side by a copper foil, is contour cut whereafter a second entirely covering copper foil is laminated to the second side of the substrate, and a conductive pattern of signal conductors and ground conductors is etched in the second copper foil. The second substrate is also contour cut and is laminated to a copper foil, whereafter a window is etched in the copper foil, corresponding to the window cut in the substrate. The second laminate thus formed is adjusted in regard of the pattern to the first laminate and is adhesively secured thereto, the side of the second laminate covered by the copper foil turned away from the side of the first laminate provided with the conductive pattern. A metal layer is thereafter applied to the surface of the first laminate facing away from the side having the conductive pattern and the lateral edges to electrically connect said surface, the ground conductors of the conductive pattern and the foil on the second substrate, whereafter components are mounted in the windows in the second laminate to the conductive pattern.

In electronic equipment for high frequencies and data signals having short transient times one portion in electronic equipment may interfere with the operation of other portions by the fact that the electromagnetical field will transfer signals over dielectric distances by induction. Such crosstalk will usually be dealt with by having the various portions of the equipment built into metal casings, which are electrically grounded and in the walls of which the electric field is short circuited, i.e. the casings will constitute shielded casings. The various portions are interconnected by coaxial cables. The signal being transferred on the coaxial cable may be purged from undesirable frequencies by means of special filters. The disadvantages of such shielded casings are partly that they are relatively costly, partly they are spaceconsuming. Another problem is that it is often difficult to provide sufficiently electromagnetically closed shields between the various portions of the electronic equipment in the case where one wants to integrate it on one single circuit board.
In conventional pattern boards often regions of the circuit board are surrounded by an etched and grounded frame incorporated in and surrounding the rest of the conductive pattern and further a ground plane is attached to the opposite side of the circuit pattern board. By soldering a metal shield on said grounded frame a region, which is fairly well but not completely shielded, is obtained. The problem in this case is that the electromagnetic radiation will leak laterally between the grounded frame and the ground plane in the laminate thus formed. This radiation can be partly confined by having holes drilled and metallized, which connect the ground plane and the grounded frame. The radiation leakage, however, may only be restricted in a certain amount in this way, since said holes cannot be located too closely to each other since this would impart a mechanical weakening of the laminate. Producing metallized holes in this way is, in addition, costly and constitutes a source of errors. Said method is particularly unsuitable for circuit boards intended for cheap and little space consuming surface mounting where holes are not required for the attachment of component legs but only as a connection between various conductive layers.

Circuit board having a lateral conductive pattern and shielded regions as well as a method of manufacturing such a board


The present disclosure provides a primary frequency modulation method for a wind turbine, which may include: detecting a current frequency of a power grid; determining an instruction value of a power change amount for a primary frequency modulation by a first determining process when the current frequency of the power grid is less than a standard frequency of the power grid, wherein the first determining process may include: determining a reference value of the power change amount for the primary frequency modulation based on the current frequency; and when it is determined that currently there is an active power headroom for the wind turbine, comparing the reference value with a current active power headroom value of the wind turbine and determining the instruction value of the power change amount for the primary frequency modulation; and performing the primary frequency modulation based on the instruction value of the power change amount.

With the continuous increase of wind power installed capacity, the impact of operating characteristics of a wind turbine on frequency stability of a power system is increasingly apparent.
Since a wind turbine often operates in a power-limited state and cannot be in an optimal power generation state for a long time, a control technology capable of performing a primary frequency modulation in a power-limited state is needed.

Primary frequency modulation method and device for wind turbine

BEIJING GOLDWIND SCIENCE & CREATION WINDPOWER EQUIPMENT CO., LTD.


The rotational angle of a rotatable object (such as the throttle valve of an automobile engine) is accurately detected by a rotational angle detector having a magnetic sensor placed in a magnetic field, the direction of which varies according to the rotational angle. The magnetic sensor generates an output that varies sinusoidally according to rotational angle. The sinusoidal output is converted into a signal that is proportional to the rotational angle under arc-sine or arc-cosine transformation. The converted signal correctly represents the rotational angle in a wide angle range. The sensor element and the circuit for converting the sensor output into the proportional output signal may be built in a single-chip integrated circuit to simplify detector structure.

This application is based upon and claims benefit of priority of Japanese Patent Application No. Hei-11-304826 filed on Oct. 27, 1999, the content of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a detector for detecting the rotational angle of a rotatable object, the detector using a magnetic sensor element.
2. Description of Related Art
An example of rotational detectors of this kind is disclosed in JP-A-5-157506. The essence of the disclosed detector is illustrated in FIGS. 7A and 7B of accompanying drawings. A Hall element 12 is placed in a parallel magnetic field generated by a cylindrical permanent magnet 11, as shown in FIG. 7A. The cylindrical magnet 11 connected to a rotatable object rotates together with the rotatable object, while the Hall element 12 stays in the magnetic field. An angle xcex8 made between an magnetosensitive surface of the Hall element 12 and the magnetic field direction changes according to rotation of the rotatable object, as shown in FIG. 7B. The Hall element 12 generates the following output voltage VH:
xe2x80x83VH=V0. sin xcex8,
where V0 is a maximum value of VH that is generated when the angle xcex8 is 90xc2x0 The output VH is fed to an outside microcomputer that calculates the rotational angle of the rotatable object based on VH.
The output VH, however, is a sinusoidal curve that is not perfectly proportional to the angle xcex8, though it is substantially proportional in a limited narrow range. In other words, the angle xcex8 is not correctly detected in a range beyond the limited narrow range. It may be possible to process the output VH in the computer to convert it into a correct rotational angle, but such conversion process makes the computer more complex.
The present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an improved rotational angle detector that correctly detects the rotational angle in a wide range without making the detector complex.
The rotational angle detector is composed of a rotor, a magnetic sensor element and circuits for processing the sensor signal. The rotor is connected to a rotatable object such as a throttle valve, the rotational angle of which is to be detected. Magnets are mounted on the rotor to generate a magnetic field therein, and a magnetic sensor element such as a Hall element is disposed in the magnetic field. The magnetic sensor element generates an output in a form of a sine or cosine wave according to the rotational angle of the rotor. The sensor output is not exactly proportional to the rotational angle because it varies in a sinusoidal waveform. A linear converter provided in the circuits converts the sensor output to a signal which is proportional, or linear, to the rotational angle of the rotor. This conversion is preferably performed under arc-sine or arc-cosine transformation. The converted sensor signal represents a correct rotational angle in a wide angle range.
The magnetic sensor element may be rotated relative to the magnetic field while making the magnetic field stationary. The linear converter and the magnetic sensor element may be built in a single-chip-integrated circuit to simplify the detector structure, or they may be separately build in respective integrated circuits if such is convenient for structuring the detector.
Preferably, the analog sensor output is converted into a digital signal, and then the digital signal is converted into the signal linear to the rotational angle under the arc-sine or arc-cosine transformation. The rotational angle detector may include two output terminals, one for an analog signal and the other for a digital signal, so that the output is adaptable to both of analog and digital outside controllers.
The rotational angle detector according to the present invention is able to correctly detect the rotational angle over a wide range without making the detector structure complex.
Other objects and features of the present invention will become more readily apparent from a better understanding of the preferred embodiments described below with reference to the following drawings.

Rotational angle detector using linear converter


This invention relates generally to a pneumatic, hydraulic or other media driver, rotating-reciprocating cylinder apparatus to be mounted on the proximal end of CNC lathe spindles, vertical or inverted machining centers, hydraulic machining work cells or rotary transfer machines to actuate work holding chucks, work holding fixtures, clamping apparatus or work supports on the distal end of said spindles. More specifically, this invention relates to an actuating system with the capability of boosting the input hydraulic pressure to the holding device by a pre-set multiple up to 5000 psi where the boost pump is integral to and rotates with the clamp cylinder assembly.

1. Field of Invention
This invention relates generally to a pneumatic, hydraulic or other media driver, rotating-reciprocating cylinder apparatus to be mounted on the proximal end of CNC lathe spindles, vertical or inverted machining centers, hydraulic machining work cells or rotary transfer machines to actuate work holding chucks, work holding fixtures, clamping apparatus or work supports on the distal end of said spindles. More specifically, this invention relates to an actuating system with the capability of boosting the input hydraulic pressure to the holding device by a pre-set multiple up to 5000 psi where the boost pump is integral to and rotates with the clamp cylinder assembly.
2. Prior Art
A variety of high speed rotating cylinders exist and are used on many different machine tools to activate clamps that turn with the work piece. To achieve high speed operation many complex and costly systems have been produced. It is often the case that sufficient hydraulic pressure to clamp the work piece with sufficient force to withstand these high rotary speeds is not available within the existing system. There are commercially available stationary hydraulic booster systems that work with an internal oscillating pump which boosts inlet pressures by pre-set multiples but until this invention there was not an efficient apparatus for incorporating such a system to rotate with a rotary reciprocating cylinder. Prior art systems include a fixed position booster which boosts the pressure before the rotary connection between the boost pump and the rotating clamp cylinder and spindle creating high pressure connections that are rotary and high speed making the hydraulic fluid seals at the rotary interface very difficult and expensive.

Rotary reciprocating intensified hydraulic actuator


In a DRAM memory cell built in a semiconductor device, a capacitor is formed on a field oxide film so as not to superpose upon a transistor. An area of the field oxide film can therefore be used efficiently. Since the capacitor can be formed before the transistor is formed, high temperature treatment in forming the capacitor does not give adverse effects on the transistor characteristics. The capacitor dielectric film can be made of material of a high dielectric constant. The capacitor dielectric layer and lower electrode are formed by patterning in succession with the same etching mask. The gate electrode is formed at the same time when the upper capacitor electrode is formed. At the same time when the gate oxide film is formed, an oxide film is formed also on the surface of the capacitor dielectric layer. Pin holes in the dielectric layer are buried by this oxidation. With a reduced number of processes, the additional number of manufacture processes for built-in memory cell in addition to the manufacture processes of logic circuit can be made small. A semiconductor device and its manufacture method are provided which have less load on processes and a small memory cell size.

a) Field of the Invention
The present invention relates to a semiconductor device and more particularly to a structure of a semiconductor device with highly integrated DRAMs and its manufacture method.
b) Description of the Related Art
In large scale integrated (LSI) circuits having mostly logic circuits fabricated by process techniques of 0.5 .mu.m rule, mainly static random access memories (SRAM) are presently used as built-in memories because of its light process load. Since a memory cell of SRAM is formed only by transistors, the memory manufacture processes can be shared with logic manufacture processes.
FIG. 4A shows a general circuit structure of an SRAM. As shown, one memory cell of SRAM requires transistors T1 to T4 constituting a flip-flop and read/write transistors T5 and T6 connected to data/word lines, totalling six transistors.
Since one memory cell of SRAM requires six transistors, it is said a realizable minimum cell size is 50 to 60 .mu.m.sup.2 even with an ingenious layout pattern. Under a growing trend towards higher integration satisfying demands for large capacity of memories and small size of chips, use of SRAMs does not realize a sufficient integration degree.
In such circumstances, DRAMs simpler in structure than SRAMs are being used in a built-in memory having a capacity of 1 Mbit or larger.
FIG. 4B shows a general circuit structure of a DRAM. One memory cell of DRAM is constituted by one transistor Td and one capacitor Cd. One current terminal of the transistor is connected to the data line, and the other current terminal is connected via the capacitor Cd to the plate line. The gate terminal of the transistor Td is connected to the word line. Read/write of one bit is carried out by charging/discharging the capacitor Cd via the transistor Td. As compared to SRAMs, high integration of DRAMs is possible because of a less number of constituent elements of one memory cell.
Even with DRAMs, however, the structure of a cell capable of further reducing the cell size and realizing higher integration has been desired for a built-in memory having a capacity of 4 Mbit or larger.
Presently, for DRAMs having a memory size of 4 Mbit or larger, a cell structure called a stacked capacitor (STC) type is used dominantly. For DRAMs having a memory size of about 1 Mbit, a cell structure called a planar type is used.
FIG. 5A shows an example of a cell structure of a currently used STC type DRAM. A semiconductor substrate 51 has a field oxide film 52 defining an active region. The active region has a transistor formed therein, the transistor being constituted by source/drain regions made of diffusion layers 53a and 53b (hereinafter the diffusion layer 53a is called a source region and the diffusion layer 53b is called a drain region) and a gate electrode 54a made of a first level polysilicon layer.
A portion encircled by a broken line .alpha. in FIG. 5A corresponds to the capacitor. A second level polysilicon film 55 and a third level polysilicon film correspond, respectively, to the lower and upper electrodes of the capacitor. A thin silicon nitride film C1 interposed between the lower and upper electrodes corresponds to the capacitor dielectric layer. This capacitor is formed above the drain region 53b, with the lower electrode 55 being electrically connected to this drain region 53b.
The transistor and capacitor are covered with an interlayer insulating film 57. An interconnection 58 is led from the source region 53a via the contact hole.
This STC type DRAM cell has such a structure that the capacitor is stacked on the transistor. The transistor is therefore required to be formed before the capacitor is formed. A problem therefore arises that capacitor forming processes with heat may degrade the performance of the transistor already formed. In addition, because of its complicated structure, the number of necessary processes is large.
FIG. 5B shows an example of a cell structure of a currently used planar type DRAM. A semiconductor substrate 51 has a field oxide film 52 defining an active region. The active region has a transistor formed therein, the transistor being constituted by a source region 53a, a drain region 53b, and a gate electrode 54a formed on a thin gate oxide film on the substrate surface.
A portion encircled by a broken line .beta. in FIG. 5B corresponds to the capacitor. A shallow impurity diffusion layer 53c is formed in the substrate surface layer continuously with the drain region 53b. On the surface of the impurity diffusion layer 53c, an SiO.sub.2 film C2 is formed, on which a first level polysilicon film 54b is formed. The diffusion layer 53c corresponds to the lower electrode of the capacitor, the first level polysilicon film 54b corresponds to the upper electrode, and the SiO.sub.2 film C2 corresponds to the dielectric layer. The transistor and capacitor are covered with an interlayer insulating film 57. An interconnection 58 is led from the source region 53a via the contact hole.
In this planar type DRAM cell, it is necessary to form, in addition to the source/drain regions of the transistor, the impurity diffusion layer as the lower capacitor electrode in the substrate surface layer. In this planar type DRAM cell, the capacitor dielectric layer is made of an SiO.sub.2 film formed at the same time when the gate insulating film is formed. Since an SiO.sub.2 film has a relatively small dielectric constant, a required area of the capacitor is broad in order to retain a necessary capacitance. Because of these reasons, there is a limit in reducing the cell size of a planar type DRAM.
As shown in FIG. 5B, an interconnection 55 made of a second level polysilicon film is being formed in the interlayer insulating film 57 above the capacitor. This interconnection 55 is essential for interconnection to the gate electrode of an adjacent memory cell, and is formed above the capacitor to reduce the cell size. An electrostatic capacitance is therefore generated between the upper capacitor electrode 54b and the interconnection 55. In order to escape the influence of this capacitance, the interlayer insulating film between the interconnection 55 and upper electrode 54b should be made thick.
As above, if SRAM is used as a built-in memory of LSI, the cell size becomes large and high integration is difficult. If STC type DRAM is used as a built-in memory, the manufacture processes become complicated and heat treatments after the formation of MOSFET may degrade the performance of transistors. If planar type DRAM is used, there is a limit in reducing the cell size although the manufacture processes are relatively simple.

DRAM capacitor having lower electrode and dielectric layer of same planar shape preformed on field DRAM oxide film


The present disclosure provides a system and device for drones with ducted rotors. In some aspects, drones may comprise one or more systems of ducted rotors. In some embodiments, ducted rotors may increase the durability of the drone, limiting exposure of the rotors to external conditions and objects. In some aspects, a drone with ducted rotors may comprise a control vane or cone that may direct airflow within the drone as a mechanism to control flight path. In some implementations, a drone may comprise expandable landing gear than may allow for controlled landing, even in the event of rotor failure. In some aspects, a drone may comprise rotatable ducted rotors.

An unmanned aerial vehicle (UAV), now commonly referred to as a drone, is a vehicle without a human pilot. Drones are pilotless aircraft that may be flown by remote control or through the use of on-board computers. The earliest UAVs were used in the military. For example, some consider the earliest version of the UAV to be balloon carriers used during the First World War, where balloon carriers were launched with incendiary firepower without a human controlling the target or destination. Since these balloons relied on wind to reach their targets, the earliest version of the UAV were not particularly successful.
After the First World War, pilotless aerial torpedoes were developed that exploded at a preset time. Aerial technology eventually caught up with human imagination, particularly helped by breakthroughs within transistor technology, leading to unmanned planes that could carry explosive payloads to predetermined targets. In the 1970s, UAVs were used as decoys during war to hoodwink opposing forces into squandering expensive ammunition. As technology advanced, interest in and demand for UAVs grew tremendously within the military by the 1980s and 1990s.
Drones were developed for a variety of purposes, such as decoy, reconnaissance, combat, logistics, research, and, eventually, commercial applications. In the commercial sector, drones can be further divided into ready-to-fly, bind-and-fly, do-it-yourself, and bare frame categories. This range is based on the user's prior knowledge of drones. For example, a budding enthusiast is more likely to purchase a "ready-to-fly" drone for their first drone experience. In its current manifestation, drones are usually made up of a body, power supply, actuators, sensors, and internal logic that enables the drone to function, like microcontrollers, control architecture, and processing software.
Some drones have started to integrate computer vision and machine learning technology into their camera systems. This enabled better tracker for people, animals, and objects as well as better situational awareness to avoid nearby obstacles. This expanded the capabilities of drones, which was otherwise limited to following global positioning systems (GPS) signals.
Drones are also being used to improve emergency prevention, response, and recovery operations, such as search and rescue operations, policing, and firefighting. Drones are being used to reduce costs, cut response times, and more effectively capture emergency response efforts for internal improvement and accountability. For example, some drones may have thermal imaging cameras to provide insights during a fire, helping direct firefighters on where to more effectively direct their water sprays. For the police, drones may be used for search and rescue missions, for crime scene documentation, and even traffic monitoring for larger events. During disaster relief situations, drones were used to assess critical infrastructure damage, show updates on recovery progress, and inform homeowners about the condition of their homes.
Despite these innovations, drone dependability and maneuverability are still ongoing issues with this use case. Drones are limited by their shape and size when facing unfavorable or dangerous weather conditions. Despite their use for visibility, there may be situations where the size of a drone limits this functionality, forcing emergency response teams to be more involved during a data gathering task. Further, drones may be limited as to how it communicates with other human beings, other drones, and other aerial vehicles during a reconnaissance or emergency mission.

Unmanned aerial vehicle with ducted rotors


A liquid crystal display unit having a dot matrix display section, a pict display section arranged at a different portion from the dot matrix display section and a connection terminal for connecting signal conductors from the dot matrix display section with an external device, wherein the pict display section is divided into a plurality of cells and the signal conductors are connected with the connection terminal via each of the cells.

The present invention relates to an Liquid Crystal Display (referred to as LCD, hereinafter) unit for illuminating characters and symbols by means of an LCD driver and, more particularly to an effective wiring art of signal conductors used in the LCD unit provided with a pict display section and a dot matrix display section, and an illuminating control method of the pict display section.
A conventional LCD unit has two types of display system, one is a pict display for displaying fixed characters, symbols and pictures and another is a dot matrix display where a plurality of cells are arranged in dot matrix and some cells are selected and illuminated to form a predetermined character by applying drive voltage to the selected cells. A certain model of the LCD unit has both the pict display section and the dot matrix display section.
FIG. 9 shows the LCD unit provided with both the dot matrix display section 31 and the pict display section 32 on its surface.
As FIG. 10 shows, signal conductors of those display sections, that is, the dot matrix display section 31 and the pict display section 32 comprise common signal conductors 1 to 15 connected to the row electrodes of the dot matrix display section 31 and the pict display section 32, and segment signal conductors 1 to 40 connected to the column electrodes of the dot matrix display section 31. These signal conductors elongate toward a connection terminal 33 for connecting an external device to the display sections 31 and 32, respectively.
With a conventional wiring of signal conductors, disposing the pict display section 32 between the dot matrix display section 31 and the connection terminal 33 as shown in FIG. 11 requires the segment signal conductors and common signal conductors connecting the dot matrix display section 31 and the connection terminal 33 to bypass the respective pict display sections 32. This results in very complicated wiring as a whole. Moreover in case the wiring space is limited, sufficient space for disposing the pict display section 32 between the dot matrix display section 31 and the connection terminal 33 cannot be obtained, thus restricting provision of the display section.
The Japanese Patent Application Laid-Open No. 31890 (1992) discloses a wiring method with decreased signal conductors as a whole by dividing a character string on one row of the dot matrix display section into a plurality of parts so that the segment signal conductor is shared by those divided parts of the character string.
In this art, as shown in FIG. 12, eight common signal conductors COMs 1 to 8 for a left half character string of the first row, eight common signal conductors COMs 9 to 16 for a right half character string of the first row, eight common signal conductors COMs 17 to 24 for a left half character string of the second row and eight common signal conductors COMs 25 to 32 for a right half character string of the second row are disposed. Segment signal conductors SEGs 1 to 50 for two left character strings of the first row and the second row, and the segment signal conductors SEGs 1 to 50 are shared by two right character strings of the first row and the second row. As a result, in case of displaying two rows (where a character with 5.times.8 dot matrix, 20 characters per a row), 32 lines of common signal conductors and 50 lines of segment signal conductors, totally 82 signal conductors are needed.
This invention has enabled to greatly reduce the number of necessary lines of signal conductors that has been 116 lines in a conventional art.
With this prior art, however, the wiring of signal conductors still requires to bypass the pict display section.

Liquid crystal display unit and illuminating control method of pict display section of said liquid crystal display device


Aspects of the disclosure include, for example, obtaining input data. Further embodiments include a determination of a fast path prediction for a first time period according to the input data based on a fast path model. Embodiments include providing instructions to deliver information to a user device according to the fast path prediction. Additional embodiments include obtaining additional input data. Embodiments include a determination of a slow path prediction for the first time period according to the input data and the additional input data based on a slow path model, retraining the fast path model according to the input data and the fast path prediction, and training the slow path model according to the slow path prediction. Embodiments include a determination of a fast path negative impact metric and determination of a slow path negative impact metric. Other embodiments are disclosed.

Generally, Internet content, such as an advertisement, can be provided without fully taking into account all of the context in which it is placed. That is, instantaneous optimization in placing Internet content, such as an advertisement, often leads to sub-optimal outcomes in the long run when additional information that would provide contextual nuance are necessarily omitted for speed. For example, a user's cookies about the user's browsing behavior, age, device type, and location may be included in determining whether to place an advertisement on a website, but bias may exist on the basis of gender, which if not considered, may result in a sub-optimal placement of the advertisement.

Methods, systems, and devices for detecting and mitigating potential bias


This disclosure addresses resin systems which contain thermosetting materials and thermoplastic modifiers, the resin systems being formed by dispersing particles of thermoplastic solids in the thermosetting materials, the particles being soluble in the resins at temperatures below the resin system gelation temperature. According to this disclosure, the systems are improved by the use of a blend of two types of thermoplastic material--a high glass transition temperature thermoplastic such as a poly(benzophenone-imide) and a high toughness thermoplastic such as a poly(ether-imide). By appropriate adjustment of the relative amounts of these two thermoplastics, resin system properties such as toughness, service temperature, thermal stability and solvent resistance can be adjusted to optimum levels.

Thermosetting resins are widely used in the formation of fiber-reinforced structural materials due to their ability to withstand high temperatures. These materials provide the high strength and high temperature capability needed in such applications as military aircraft.
Thermosetting resins which have been used in this context include epoxy resins and bismaleimide resins. The latter are particularly beneficial due to their high glass transition temperature, their high capability of withstanding hot wet environments, and their low smoke and toxicant emission.
The beneficial properties of thermosetting resins are unfortunately offset by a brittleness or low toughness resulting in low damage tolerance. Toughness is extremely important in high-performance structures, since high loads must be borne both within the plane of the composite and in directions normal to the plane of the composite. Among the solutions offered for increasing toughness are the use of thermoplastics in combination with the thermosetting resins. This usually occurs, however, at the expense of processability, the thermoplastic additive causing an increase in the viscosity and the softening point of the material.
Patent application Ser. No. 07/312,016, filed Feb. 16, 1989, discloses resins made from a continuous phase of thermosetting resin containing a dispersed phase of thermoplastic material, the thermoplastic material being one which is solid at ambient temperatures but which dissolves in the thermosetting resin at a temperature below the gelation temperature of the thermosetting resin. The term "gelation temperature" as used herein refers to the temperature at which gelation occurs in the normal heat processing of the resin to achieve a thermal cure, as distinguished from any gelation which might occur very slowly at lower temperatures or during storage.
According to the present invention, the thermoplastic particles in the procedure of patent application Ser. No. 07/312,016 are replaced by particles which are a single-phase blend of at least two thermoplastics from at least two distinct classes. It has indeed been discovered that the resin which results when these particles are dispersed in a matrix of thermosetting polymer and then cured has unique properties in terms of toughness, processability, utility at high temperatures and other performance and use characteristics.
The blend is a mutually compatible combination of thermoplastics, at least one from each of the following two classes of thermoplastics:
(i) a thermoplastic polymer with a glass transition temperature (T.sub.g) of at least about 250.degree. C., and
(ii) a thermoplastic polymer with a fracture toughness of at least about 2.5 ksi .sqroot.in, and a glass transition temperature of less than about 240.degree. C. These values of T.sub.g represent the polymer species when molded individually, although this is not the form which they assume either in the particles or in the final product.
As used herein, the term "compatible" designates species which are miscible such that when combined, these species form a single homogeneous phase. The term "blend" designates a combination of the species, such that any single particle of the blend contains both species intimately mixed together in a single homogeneous solid phase, in contrast to mixtures of particles where each particle contains only one such species. The blends herein are thus analogous to alloys in the metallurgical context.
In contrast, the combination formed by first combining the thermoplastic blend particles with the fluid thermosetting resin precursor and then curing the combination at elevated temperature is not homogeneous. The cured combination instead exhibits a two-phase morphology, one such phase rich in thermoplastic material and the other rich in thermoset material. As will be explained below, the phases are often inverted upon cure, the dispersed phase being the phase rich in thermosetting material and the continuous phase being the phase rich in thermoplastic material.
The term "composite" is used herein to denote the combination of the two-phase thermosetting/thermoplastic resin and reinforcing material coated or impregnated with the resin.
Critical to this invention is the inclusion of at least one thermoplastic species from each of the two classes designated above. The present invention further extends, however, to the inclusion of additional thermoplastics compatible with these two, the additional thermoplastics either falling within one of the two classes or falling outside both. In these cases, the thermoplastic blend is a combination of three or more species. In preferred embodiments of the invention, however, the combination is limited to one from each of the two classes designated above.
It has further been discovered that by varying the weight ratio of the two thermoplastic components in the particles, one can control the properties of the final thermosetting/thermoplastic resin which is formed when the particles are combined with the thermosetting material precursor and the entire combination is cured. This is a further unexpected feature, not predictable from the known qualities of these resins, since it permits one to tailor the properties of the final resin to specific needs and performance requirements by adjustment of the relative amounts of the thermoplastic components alone. It is particularly surprising and nonobvious that the thermoplastics, when combined in the blend, yield a composite which displays a balance of properties far superior to those of the individual components standing alone.
Other features, advantages and further aspects of the invention will be apparent from the description which follows. The overall resin finds utility both as an adhesive and as the resin component in structural composites.

Resin systems of improved toughness and high temperature performance and method therefor


A method of preparing metal chalcogenides from elemental metal or metal compounds has the following steps: providing at least one elemental metal or metal compound; providing at least one element from periodic table groups 13-15; providing at least one chalcogen; and combining and heating the chalcogen, the group 13-15 element and the metal at sufficient time and temperature to form a metal chalcogenide. A method of functionalizing the surface of semiconducting nanoparticles has the following steps: providing at least one metad compound; providing one chalcogenide having a cation selected from the group 13-15 (B, Al, Ga, In, Si, Ge, Sn, Pb, P, As, Sb and Bi); dissolving the chalcogenide in a first solution; dissolving the metal compound in a second solution; providing and dissolving a functional capping agent in at least one of the solutions of the metal compounds and chalcogenide; combining all solutions; and maintaining the combined solution at a proper temperature for an appropriate time.

Because of their wide range of physical and chemical properties and unique structural characteristics, chalcogenides (sulfides, selenides and tellurides) of metals are widely used in industrial applications such as catalysis, lubrications, battery fabrication, ionic conduction, refractories, pigments, sensors, and optical and magnetic devices. Among the various preparation methods of metal chalcogenides, the simplest method to date is based on direct reactions between chalcogen elements and elemental metals at elevated temperatures. Most of the other methods utilize metathetical reactions of metal source compounds and binary chalcogenides such as H2S, H2Se, H2Te, CS2, Y2S3, Na2S, Na2S2, K2S and K2S2. The reactions can take place in solid, liquid or gaseous state as well as in solution.
Discovery and utilization of new chalcogen sources are of great value for the development of new methodologies that may overcome the limitation of the current methods of chalcogenide preparation. For example, the synthesis of metal polysulfides has not been straightforward by the existing methods because many polysulfides decompose at elevated temperatures and the sources of the polyanions are relatively scarce. H2S alone is not an efficient source of S0, and the thermodynamics of the thermal decomposition of H2S are not favorable at low temperatures. For instance, at temperatures below 550° C. the equilibrium concentration of sulfur is less than 1%, and even at 900° C. it is only 13%. Reactions with elemental sulfur often require a pressurized reaction container and/or a multi-step procedure. More recently, solid-state metathesis and/or solution methods have been used for the preparations of disulfides of Fe, Co, Ni, La and Pr by employing Na2S2, K2S2 or Na2S5. FeS2 and CoS2 have also been prepared at higher temperatures by reacting H2S with starting materials that contain the corresponding metal ions of high oxidation states, but the problem of incomplete reactions and/or of impurities still remains.
Utilization of boron chalcogenides has not been previously reported for preparation of inorganic metal chalcogenides. That is, even the most heavily studied boron chalcogenides to date, boron sulfides (B2S3, BS2, and nonstoichiometric compounds with intermediate B/S ratios), have not been used in solid state syntheses other than for preparations of thioborates, and their use for sulfidation has been reported only in organic or organometallic reactions, and even there only sporadically. The sulfides do not have a well-defined melting point, but they begin to sublime at about 300° C. under vacuum from our experience as well as that of others. Previously stoichiometric B2S3 (s) vaporizes congruently to give B2S3(g) and its polymers, while sulfur-rich samples vaporize incongruently into (BS2)n(g) and (B2S3)n(g). The corrosive nature of the gaseous boron sulfides reported in the literature is probably the main reason for their scarce use in solid state reactions; and indeed the silica reaction vessels need to be heavily carbon-coated for the synthesis of alkali thioborates, which is carried out typically above 600° C. for several days.
However, for sulfidation reactions, the corrosiveness of the gaseous boron sulfides could be advantageous, particularly under low-temperature reaction conditions which are often required in preparation of nanostructural materials. Furthermore, the boron sulfides on the sulfur-rich end may allow access to the polysulfide compounds that exist only at low temperatures and decompose at elevated temperatures.

Preparation of metal chalcogenides from reactions of metal compounds and chalcogen


A plant grown from seeds derived from a new interhybrid of three plants of the Momordica genus has been cultivated. The new plant hybrid has a faster growth rate than the parent species. Parts of the new interhybrid plant which, when ingested by an individual, have blood glucose and/or insulin regulating properties. Foods and/or beverages containing parts or extracts of the new interhybrid plant and which to promote weight control or loss and/or blood glucose regulation are also disclosed.

Blood glucose levels play an important role in a person's energy levels and, in general, all bodily functions. A continuous excess of glucose in a person's blood stream is often an indicator of weight and/or blood glucose regulation issues. Generally, an individual's blood glucose levels should fall between about 70 to about 110 mg/ml.
Elevated blood glucose levels (i.e., greater than about 110 mg/dl) typically triggered by alimentary habits, can have a severe impact on an individual's health and can lead to a wide range of problems. For example, diabetes, heart disease, stroke, high blood pressure and blindness are some of the complications that can be derived from prolonged high blood glucose levels. Diabetes, in particular, has been shown to be a precursor of kidney and nervous system disorders and can also cause dental disease and complications of pregnancy.
Blood sugar imbalances attributable to diabetes are typically treated or controlled using insulin or insulin mimetics. For patients who are pre-diabetic and/or are non-insulin dependant, other forms of treatment or intervention may be employed to control blood glucose levels. For example, lifestyle changes that include weight management, nutritional control and/or counseling, and/or exercise regimens may be prescribed or recommended.
However, there is a need and a desire for a product, such as a natural product, that is effective for lowering blood glucose levels. Further, there is a need and a desire for an over-the-counter (OTC) product that can be utilized alone or in combination with other rehabilitative therapies to control blood glucose levels. There is an additional need and a desire for a natural product that can be used to supplement diet and exercise and/or promotes weight loss or control.
In another aspect, a product that is useful for controlling blood glucose and/or insulin levels can be advantageously included in foods and/or beverages used before, during and/or after exercise to maintain steady energy levels and/or hydration. For example, there is a need and a desire for a product or ingredient which promotes the maintenance of steady blood glucose levels that can be used in a sports drink, gel or energy-type food product.
Sports drink formulations generally fall into one of three categories. Isotonic sports drinks are generally designed to help athletes rehydrate as well as to maintain and/or replenish electrolytes such as, for example, sodium, potassium, calcium and magnesium, and other nutrients which can be depleted during strenuous activities. Some isotonic sports drinks may also include carbohydrates such as glucose for energy replenishment.
Another group of sports drinks includes carbohydrate-rich energy drinks. These drinks are specifically designed for use by physically active individuals and are primarily used shortly before or after exercise to boost muscle glycogen stores and help optimize sporting performance. Carbohydrates used in such energy sports drinks are typically derived from sucrose, fructose, glucose polymers, maltodextrin and/or polylactate. Energy sports drinks are less about replacing lost fluid and more about keeping the working muscles supplied with energy during very long and sustained workouts. The disadvantage of energy sports drinks is that their high carbohydrate concentrations tend to slow down the rate of water absorption, particularly during hard exercise.
Recovery sports drinks fall into the third category. Recovery sports drinks are generally taken after exercise and typically include water, carbohydrate and amino acids. Recovery sports drinks may include additional nutrients as electrolytes, minerals, vitamins needed to aid metabolism of the ingested carbohydrate, and protein to promote muscle recovery.
Generally, each of the above sports drinks is designed to provide a particular effect or benefit depending upon the activity an individual is engaged in or the point at which the beverage is ingested, i.e., rehydration during and after strenuous activities where electrolyte loss via perspiration is a concern; energy replenishment during prolonged physical activity; and post-activity muscle recovery. Currently, a sports drink formulation which addresses all three desired benefits, that is rehydration, energy replenishment and muscle recovery support, is not believed to be commercially available. Further, current commercially available sports drinks have not been designed to manage or maintain blood glucose and/or insulin levels, thereby providing an athlete with a steady level of energy throughout a workout or competition
In view of the above, there is a need and a demand for a sports drink formulation capable of providing rehydration, energy replenishment, and muscle recovery support in a single formulation. There is further need and a demand for a sports drink formulation having blood sugar and/or insulin regulatory properties.

Cultivated momordica species and extract thereof

Nutritional Health Institute Laboratories, LLC


A system for injection of a fluid into a body includes: a source of a first fluid, a source of a second fluid; the first fluid being less toxic than the second fluid; at least one pressurizing system in operative connection with the source of the first fluid and with the source of the second fluid; at least one controller in operative connection with the pressurizing system; and at least a first sensor in communicative connection with the controller. The first sensor is adapted to transmit a signal of a detected change in fluid level in tissue indicative of extravasation to the controller. The controller is adapted to cause injection of the first fluid into the body to determine if extravasation of the first fluid occurs using the sensor in an administration phase before injection of the second fluid.

The present invention relates generally to the devices, systems and methods of detecting increased fluid levels in tissue, and particularly to devices, systems and method of detecting increased fluid levels associated with extravasation in tissues and controlling powered injectors in response to such detection.
The following information is provided to assist the reader to understand the invention disclosed below and the environment in which it will typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding of the present invention or the background of the present invention. The disclosure of all references cited herein are incorporated by reference.
Elevated fluid levels in tissue can arise as a result of introduction of a fluid into the body, for example, during an injection procedure. In that regard, in many medical diagnostic and therapeutic procedures, a physician or other person injects fluid into a patient and, particularly, into a patient's blood vessels. Moreover, in recent years, a number of injector-actuated syringes and powered injectors for pressurized injection of contrast medium in procedures such as angiography, computed tomography, ultrasound and NMR/MRI have been developed. Such pressurized injectors can also be use in the delivery of therapeutic agents.
Extravasation or infiltration is the accidental infusion or leakage of an injection fluid such as a contrast medium or a therapeutic agent into tissue surrounding a blood vessel rather than into the blood vessel itself. Extravasation can be caused, for example, by rupture or dissection of fragile vasculature, valve disease, inappropriate needle placement, or patient movement resulting in the infusing needle being pulled from the intended vessel or causing the needle to be pushed through the wall of the vessel. High injection pressures and/or rates of some modem procedures can increase the risk of extravasation. In computed tomography, for example, contrast injection flow rates can be in the range of 0.1 to 10 ml/s.
Extravasation can cause serious injury to patients. In that regard, certain injection fluids such as contrast media or chemotherapy drugs can be toxic to tissue. It is, therefore, very important when performing fluid injections to detect extravasation as soon as possible and discontinue the injection upon detection.
Several extravasation detection techniques are known in the art. Two simple and very useful techniques for detecting extravasation are palpation of the patient in the vicinity of the injection site and simple visual observation of the vicinity of the injection site by a trained health care provider. In the palpation technique, the health care provider manually senses swelling of tissue near the injection site resulting from extravasation. By visual observation, it is also sometimes possible to observe directly any swelling of the skin in the vicinity of an injection site resulting from extravasation.
In a procedure involving injection of a fluid that can cause significant harm if extravasation occurs, one can first inject a relatively benign fluid through the needle/catheter and determine if an extravasation of the relatively benign fluid occurs. Published U.S. Patent Application No. 2002/0183613, the disclosure of which is incorporated herein by reference, for example, discloses a method of preventing extravasation of a contrast agent during a computed tomography injection using an automatic injector device. The method includes the steps of establishing the absence of extravasation using an absorbable injectate, such as saline, prior to injecting the contrast agent. The automatic injector includes a computerized injector head capable of switching between two injectates without physical human intervention. During, the method an operator first attempts to position distal end of a percutaneous implement such as a catheter in the vessel such that fluid communication is established between the lumen of the catheter and the vessel. The injector is then instructed to inject saline through the catheter lumen. A determination is then made (via palpation/observation) if an extravasation of the saline has occurred. If it is determined that no extravasation has occurred, the injector is instructed to inject contrast agent. If an extravasation is determined to have occurred during the saline injection, the process steps of repeated positioning the catheter within the blood vessel, injection saline and determining if an extravasation of saline has occurred are repeated.
In addition to palpation and observation, there are a number of automated methods of detecting extravasation that may include automatic triggering of an alarm condition upon detection.
In that regard, several plethysmographic detection techniques are available. For example, mercury strain gauge plethysmographs measure the volume change resulting from venous blood flow in a cross sectional area of a limb of a patient. Air cuff or pulse volume recorder plethysmographs measure the changes in pressure within a recording cuff. Such plethysmographs can be cumbersome to operate and/or insensitive to small changes in volume.
Impedance plethysmographs use low-frequency electromagnetic energy transmitted via galvanic contact with the skin to measure changes in the electrical impedance in a defined tissue volume of a limb. Detection of extravasation via impedance changes is disclosed, for example, in U.S. Pat. Nos. 5,964,703 and 5,947,910, the disclosures of which are incorporated herein by reference. In this method, an impedance change of a certain level relative to a baseline measurement in the vicinity of the injection site is interpreted as being an extravasation. A change in impedance occurs during extravasation because injection fluid in the tissue of the patient changes both the volume and the electrical impedance properties of the tissue. Use of electrodes in impedance plethysmographs can, however, result in instabilities. For example, maintaining suitable electrical (ohmic or galvanic) contact between the electrodes of impedance plethysmographs and the skin of the patient is often very difficult.
Photo-plethysmographs measure the optical scattering properties of capillary blood to detect the presence of extravasated fluids in tissue. An example of a photo-plethysmograph is described in U.S. Pat. No. 4,877,034, the disclosure of which is incorporated herein by reference. Because light is heavily absorbed in tissue, however, the sensitivity of photo-plethysmographs is generally limited to the top ¼ inch of tissue. Many extravasations, however, occur deeper than ¼ inch. Moreover, the injection medium may flow into interstitial spaces remote from the photoplethysmograph sensors and go undetected.
A number of extravasation detection devices attempt to measure temperature differences to determine if an extravasation has occurred. For example, U.S. Pat. No. 4,647,281 discloses subcutaneous temperature sensing of extravasation to trigger an alarm. In this method of extravasation detection, an antenna and a microwave radiometer instantaneously measure the temperature of the subcutaneous tissue at the site where fluid is injected by measuring microwave radiation emitted naturally from the body. An algorithm periodically determines the temperature difference between tissue and injected fluid, and compares the difference to a fixed threshold. An alarm processor uses the comparison to determine an alarm condition.
In addition, U.S. Pat. No. 5,334,141, the disclosure of which is incorporated herein by reference, discloses a microwave extravasation detection system employing a reusable microwave antenna and a disposable attachment element for releasably securing the microwave antenna to a patient's skin over an injection site. The attachment element holds the antenna in intimate contact with the patient's skin to optimize microwave transfer therebetween, while shielding the antenna from environmental noise signals. U.S. Pat. No. 5,954,668, the disclosure of which is incorporated herein by reference, also discloses use of a microwave antenna to sense temperature of tissue to detect extravasation. Although measurement of temperature changes and emissivity using microwave energy can result in instantaneous detection, temperature differences are often too small for practical measurement.
Published U.S. Patent Application Publication Nos. 2003/0036674 and 2003/0036713 and Published PCT International Patent Application Nos. WO/2003/009753, WO/2003/009752 and WO 2005/043100, assigned to the assignee of the present invention, the disclosures of which are incorporated herein by reference, disclose transmitting and receive antenna elements, sensing methods and processing algorithms suitable for the detection of elevated fluid levels (including those caused by extravasation) using active transmission of microwave energy into tissue. The studies of sensors incorporating such antenna elements have shown that electromagnetic energy having, for example, a frequency in the range of approximately 300 MHz to approximately 30 GHz (and, more preferably, in the range of approximately 1 GHz to approximately 10 GHz, and, even more preferably, in the range of approximately 3 GHz to approximately 5 GHz) provides good penetration into tissue. Such electromagnetic energy is launched into the subcutaneous tissue and a resultant signal is measured. Electromagnetic energy in the frequency range set forth above has been found to transmit through the skin and to transmit or propagate well within, for example, fat. Good transmission through the fat layer is beneficial for detection of extravasation as many extravasations occur in the fat layer.
It is desirable to develop improved devices, systems and methods of detecting and preventing extravasation.

Devices, systems and methods for detecting increase fluid levels in tissue


A tube structure (1) comprising an inner tube (3) of metal and an outer tube (2) of metal, wherein the inner tube (3) extends in the outer tube (2), wherein a spacer tube (4) is located between the inner tube (3) and the outer tube (2), wherein the spacer tube (4) comprises at least one slit (5), wherein the at least one slit (5) extends in a longitudinal direction of the spacer tube (4) and over an entire longitudinal extension of the spacer tube (4), and wherein the at least one slit (5) forms a space in a radial direction of the tube structure (1) extending from an outer surface (7) of the inner tube (3) to an inner surface (8) of the outer tube (2), wherein the tube structure (1) further comprises at least one signal line (9) located in the at least one slit (5) of the spacer tube (4), wherein the at least one signal line (9) extends in the longitudinal direction of the spacer tube (4).

The present disclosure relates to a tube structure comprising an inner tube of metal and an outer tube of metal, wherein the inner tube extends in the outer tube. The present disclosure furthermore relates to a method for manufacturing a tube structure comprising the steps of providing an inner tube of metal and an outer tube of metal.
Tubes of metal, in particular of stainless steel, are used in a plurality of applications, in which the tubes are subject to multiple stresses. These stresses may for example lead to pipe bursts, which not only require a replacement of the respective tube, but also increase costs. In some cases, sensors are therefore attached to these tubes, which will indicate and also send a signal when a damage appears in the tube. However, it has proven to be very difficult to protect the attached sensors against environmental influences.
It is an aspect of the present disclosure to provide a solution to this problem by providing a tube structure of metal as well as a method for manufacturing such a tube structure, wherein at least one signal line can be protectively located within the tube.

Tube structure with a protected sensor and method for manufacturing a tube structure with a protected sensor