A hybrid electrical ice protection system implements three ice protection methods in various combinations. The ice protection methods include the fully-evaporative anti-ice protection method, the wet running anti-ice protection method, and the de-ice method. The particular methods that are implemented vary, depending on the particular aircraft structure for which ice protection is being provided and on the power condition of the aircraft.

When an aircraft is flown during certain atmospheric conditions, ice can form and potentially accumulate on one or more of its exterior surfaces. Such ice formation and accumulation can result from, for example, impingement of atmospheric water droplets. The formation and accumulation of ice can have certain adverse and/or deleterious effects on aircraft performance.
For example, following its formation on an exterior surface, ice can break loose and enter the aircraft engines, or collide with protruding surfaces such as antennas, wings, moveable control surfaces, or various structures on the ground. Ice accumulation on airfoil surfaces such as wings and empennages can also adversely affect airfoil aerodynamic performance. In addition, the weight of any accumulated ice may change the overall weight and/or center of gravity of the aircraft. Moreover, ice accumulation on moveable surfaces may interfere with the operation of the moveable surface. Consequently, many aircraft include an ice protection system that either prevents the formation of ice on aircraft surfaces or removes ice that forms on such surfaces.
An aircraft ice protection system is typically configured to implement one, or perhaps two, types of ice protection methods. The ice protection methods that may be implemented are generally categorized as either anti-ice methods or de-ice methods. Anti-icing methods typically prevent ice formation on aircraft surfaces altogether, whereas de-ice methods typically allow ice to form on aircraft surfaces and periodically removes the formed ice.
Generally, there are two known anti-ice methods that may be implemented by an aircraft ice protection system. These anti-ice methods include the fully-evaporative method and the wet running method. The fully-evaporative anti-ice method fully evaporates all impinging water by heating the aircraft structure to a relatively high temperature. With the wet running method, ice formation is prevented by heating, or applying freezing point depressants to, the areas where the water is impinging. The impinging water is not evaporated, but instead runs downstream of the impinging area.
As regards de-icing methods, there are generally three different types, thermal, chemical, and mechanical. The thermal de-ice method uses thermal energy to raise the temperature of the surface, either electrically or by hot engine bleed air. The chemical de-ice method is implemented by applying a chemical freezing point depressant to the ice through pores in the structure. The formed ice then turns to slush and is swept away by the airstream. The mechanical de-ice method is typically implemented by using one or more devices to deform the exterior surface of the structure to break up the ice and allow it to be swept away by the airstream.
Although the above-described anti-ice and de-ice methods are generally safe, reliable, and robust, each suffers certain drawbacks. For example, the fully-evaporative anti-ice method requires a significant amount of thermal energy to implement. While the running wet anti-ice method requires less thermal energy than the fully-evaporative method, the amount of energy may still be significant. As regards the de-ice methods, although each of the above-described de-ice methods may require less energy to implement than either of the two anti-ice methods, the use of only a de-ice method on an aircraft is typically not implemented. Rather, a de-ice method, if implemented, is typically done so in combination with either the fully-evaporative anti-ice method or the wet running anti-ice method. This is typically done because, for example, ice formation on the some of the aircraft surfaces may adversely impact flight performance, and ice that is removed from an engine nacelle may be ingested into the engine, which can have deleterious effects.
In view of the foregoing, it may be seen that currently known aircraft ice protection systems typically use a relatively significant amount of energy. Moreover, as may be appreciated, the aircraft ice protection system is typically treated as a system that is required to be available throughout the flight of an aircraft. As such, even if the aircraft were to experience a highly unlikely event that resulted in the aircraft being able to supply less than full electrical power to its electrical loads, the aircraft ice protection system may still need to be operated at full capability.
Hence, there is a need for an aircraft ice protection system and method that can implement an adequate level of ice protection for an aircraft even if the aircraft were to experience a highly unlikely event that resulted in the aircraft being unable to supply full electrical power. The present invention addresses at least this need.

Hybrid electrical ice protection system and method including an energy saving mode


A dielectric layer is formed from an oxide containing Sn and at least one of Zn, Zr, Si and Ga. The molar percentages of Sn, Zn, Zr, Si, and Ga, relative to the total elements in the oxide, represented by a, b, c, d, and e, respectively, satisfy the conditions (1)-(7): (1) 0≤b/(a+b)≤0.6, (2) 0≤(c+d)/(a+b+c+d+e)≤0.5, (3) 0≤b≤50, (4) 0≤c≤40, (5) 0≤d≤45, (6) 0≤e≤40, and (7) 20≤b+c+d+e≤80. The dielectric layer enables favorable information recording in an oxide-based recording layer on which the dielectric layer is directly overlaid, does not require preventive measures for health hazard, and is superior in durability.

Optical recording media are represented by optical discs such as CDs, DVDs and the like, and classified into three types: read-only, recordable, and rewritable. In addition, as a recording procedure for the optical recording media, phase-change of a component material of the recording layer, an interlayer reaction of multilayered recording layer, decomposition of a component material of the recording layer, and the like have been known. Organic dye materials have been widely used for formation of the recording layer of a recordable optical disc; however, in recent years, enhanced densification of recording has led to use of inorganic materials.
A recordable optical recording medium employing a metal oxide as the inorganic material for the recording layer has been proposed (Patent Document 1). The optical recording medium of Patent Document 1 is of a decomposition type, in which indium oxide and palladium oxide are contained in the recording layer, and the recording layer releases oxygen upon irradiation with laser. In the case of using an oxide in the recording layer, information is recorded through decomposition of the oxide. In order to inhibit time-dependent deterioration of the recording layer or to enhance signal characteristics of the recording layer, overlaying a dielectric layer directly on both faces of the recording layer has been proposed.
Patent Document 1 proposes using indium oxide, indium sulfide, etc. as a material of the dielectric layer of the optical recording medium. An oxide comprising indium ensures electric conductivity of a sputtering target to increase film-forming rate, whereby shortening of the time period of the process is enabled; however, since indium is designated as a specified chemical substance, preventive measures for health hazard are required. On the other hand, the sulfide causes sulfuration in an adjacent layer due to time-dependent alteration, and may therefore impair reliability of the optical recording medium.
In regard to the optical recording medium, there is a demand for improvement of the recording characteristic (power margin) of the recording layer, for enabling support of widely different intensities of recording laser.

Dielectric layer, optical recording medium, sputtering target and oxide


A power supply apparatus has a battery and a temperature detection circuit. The battery has n battery cells, and the temperature detection circuit has m temperature detection units. Each temperature detection units has a temperature sensor that is thermally coupled to one or more of the battery cells and whose electrical resistance decreases as the temperature of the battery cell or battery cells to which it is thermally coupled increases, a serial resistor that is connected in series with the temperature sensor, and a first diode whose cathode is connected to the node between the temperature sensor and the serial resistor. The serial circuit formed by the temperature sensor and the serial resistor receives a predetermined voltage such that, as the electrical resistance of the temperature sensor decreases, the voltage at the node decreases. The first diodes have anodes thereof connected together.

1. Field of the Invention
The present invention relates to a power supply apparatus for use, for example, in a vehicle to drive a motor for making the vehicle run, or in an electric appliance to drive a load. More particularly, the present invention relates to a power supply apparatus incorporating a temperature detection circuit for detecting the temperature of a battery.
2. Description of Related Art
A vehicle-driving battery for supplying electric power to a motor for driving a vehicle yields a high output voltage thanks to a large number of battery cells, secondary cells, connected in series. This permits a motor to yield an output high enough to make an automobile run. In a power supply apparatus incorporating such a vehicle-driving battery, when the battery is made to discharge a large current to make a motor sharply accelerate an automobile, or when the battery is charged nearly to the fully-charged state with a large current while an automobile is running down with regenerative braking applied, or when the outside air temperature and thus the ambient temperature is abnormally high, or under other conditions, the temperatures of the battery cells become considerably high.
Moreover, a power supply apparatus for a vehicle has a very large number of battery cells, as many as 100 or more of them, connected in series to yield an output voltage as high as 200 V to 400 V. When a large number of battery cells connected in series are charged and discharged, an equal current flows through all the battery cells. However, not all the battery cells deteriorate evenly; that is, only one or more particular battery cells may deteriorate. Variations inevitable in the manufacturing process, differences in external/ambient factors such as the use temperature, etc. cause the individual battery cells to deteriorate unevenly. If any battery cell deteriorates and the full capacity to which it can be charged becomes substantially smaller, charging and discharging that battery cell in the same way as the other battery cells cause it to be overcharged or overdischarged. This makes the cell temperature higher, further promoting the deterioration.
Typically used as battery cells for vehicle-driving batteries are nickel hydride cells and lithium ion secondary cells. Both types of secondary cell exhibit poorer characteristics at higher temperatures, and, at still higher temperatures, exhibit thermal runaway and quickly deteriorate. To prevent this, in a power supply apparatus for a vehicle, the temperatures of individual battery cells are detected. If the temperature of any battery cell becomes, for example, higher than 55° C., the contactor connected to the output side of the vehicle-driving battery is turned off to cut the current and thereby prevent the detrimental effects of raised temperature.
To achieve this, in a conventional power supply apparatus, PTC (positive temperature coefficient) sensors serving as temperature sensors are fixed to and kept in contact with the surface of individual battery cells. This type of power supply apparatus is disclosed, for example, in Japanese Patent Application Laid-Open No. H10-270094 (hereinafter referred to as Patent Publication 1). In the power supply apparatus disclosed in Patent Publication 1, a large number of PTC sensors fixed to individual battery cells are connected in series, and the total resistance of the serially connected PTC sensors is measured. When the temperature of a PTC sensor becomes higher than a set temperature, its electrical resistance abruptly becomes higher. Thus, when the temperature of any of the battery cells becomes higher than the set temperature, the electrical resistance of the serial circuit composed of the PTC sensors becomes higher. Hence, by measuring the electrical resistance of the serial circuit, it is possible to detect that there is a battery cell whose temperature is higher than the set temperature.
However, in a case where a large number of PTC sensors are used, it is impossible to accurately detect the temperatures of the individual battery cells. This is because it is difficult to give all the PTC sensors equal characteristics. For example, with a circuit for detecting the temperatures of individual battery cells by the use of a large number of PTC sensors whose set temperature, i.e., the temperature over which their electrical resistance abruptly increases, includes an error of up to 10%, it is impossible to accurately detect, for all the battery cells, whether or not the temperatures of the individual battery cells are higher than the set temperature. Moreover, in a case where, as disclosed in Patent Publication 1 mentioned above, a large number of PTC sensors are connected in series and their total electrical resistance is detected, the larger the number of PTC sensors serially connected, the more difficult it is to accurately detect the temperatures of the battery cells. This is because, the larger the number of PTC sensors serially connected, the smaller the proportion of the rise in their total electrical resistance that occurs when the electrical resistance of any PTC sensor increases.


This invention relates to methods of sequencing DNA. More specifically, this invention relates to methods of sequencing both the sense and antisense strands of DNA through the use of blocked and unblocked sequencing primers. In brief, these methods include the steps of annealing an unblocked primer to a first strand of nucleic acid; annealing a second blocked primer to a second strand of nucleic acid; elongating the nucleic acid along the first strand with a polymerase; terminating the first sequencing primer; deblocking the second primer; and elongating the nucleic acid along the second strand.

The present invention relates to a method for the base sequencing of deoxyribonucleic acid (DNA). More specifically, this invention relates to methods of sequencing both the sense and antisense strands of DNA through the use of blocked and unblocked sequencing primers.
Genome sequencing offers the possibility of diagnosis, therapy and prevention of illnesses as well as the targeted modification of the human genome. Rapid sequencing methods are required to allow the use of this potential. Base sequencing of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) is one of the most important analytical techniques in biotechnology, the pharmaceutical industry, food industry, medical diagnostics and other fields of application.
There are many DNA sequencing methods available, such as the Sanger sequencing using dideoxy termination and denaturing gel electrophoresis (Sanger, F. et al., Proc. Natl. Acad. Sci. U.S.A. 75, 5463-5467 (1977)), Maxam-Gilbert sequencing using chemical cleavage and denaturing gel electrophoresis (Maxam, A. M. & Gilbert, W. Proc Natl Acad Sci USA 74, 560-564 (1977)), pyro-sequencing detection pyrophosphate (PPi) released during the DNA polymerase reaction (Ronaghi, M. et al., Science 281, 363, 365 (1998)), and sequencing by hybridization (SBH) using oligonucleotides (Lysov, I. et al., Dokl Akad Nauk SSSR 303, 1508-1511 (1988); Bains W. & Smith G. C. J. Theor Biol 135, 303-307(1988); Drnanac, R. et al., Genomics 4, 114-128 (1989); Khrapko, K. R. et al., FEBS Lett 256. 118-122 (1989); Pevzner P. A. J Biomol Struct Dyn 7, 63-73 (1989); Southern, E. M. et al., Genomics 13, 1008-1017 (1992)).
Ronaghi et al., (Anal. Biochem. 267, pp. 65-71 (1999)) referred to a method of sequencing both strands of a nucleic acid. The method involves PCR amplification of a template nucleic acid with a biotinylated primer and a non-biotinylated primer. The amplified product, comprising a biotinylated strand and a non-biotinylated strand is strand separated. The authors referred to the use of streptavidin coated bead for strand separation. The biotinylated strand remains attached to the bead while the non-biotinylated strand is separated from the bead under denaturing conditions. The two strands (biotinylated and non-biotinylated) are sequenced separately. Unlike the present invention which uses solid-phase sequencing for both strands, this method uses solid-phase sequencing for the biotinylated strand and solution phase sequencing for the non-biotinylated strand. Hence, Ronaghi's method is similar to the traditional method of DNA sequencing comprising strand separation (e.g., using a urea gel) of a template before sequencing. Thus, Ronaghi's method suffers from the same disadvantage as the traditional methods; requirement of a labor intensive step of strand separation and isolation of individual strands prior to sequencing. The disadvantages of Ronaghi's method increases geometrically as the number of parallel sequencing reactions increase. For example, the parallel sequencing of 1000 double stranded templates would require 1000 separations and 2000 single strand isolations. Furthermore, Ronaghi's method, like all methods based on strand separation, is limited to the determination of sequences from two primers (one for each strand) per double strand template.
Sequencing based on chemical cleavage has proven to be difficult to automate. Other sequencing methods are labor intensive due to the need to perform a hybridization step for every sequencing effort. In many situations, the hybridization step is the rate-limiting step in a sequencing reaction.
Attempts have been made for sequencing from two ends of a nucleic acid using, for example, two distinctly labeled sequencing primers (e.g., Li-Cor of Lincoln, Nebraska) in a Sanger sequencing reaction (Sanger, F. et al., Proc. Natl. Acad. Sci. U.S.A. 75, 5463-5467 (1977). These methods are variations of manual sequencing and require a size fractionation (e.g., a gel) step to determine a sequence. While size fractionation may be suitable for small sample sizes, genomic sequencing using size fractionation techniques would require 1,500,000 size fractionation gels (assuming an optimistic capability of 2000 bp per gel). For these reasons, sequencing methods involving size fractionation have not been adapted to sequencing of human genomes.


A universally accessible healthcare device having a communication path and a server. The healthcare device generates a set of medical information and the server provides access to the medical information using an open standard network protocol on the communication path. HTML Files may be generated on the fly by the server in response to an HTTP command from a requesting web client.

1. Field of Invention
The present invention pertains to the field of healthcare devices. More particularly, this invention relates to healthcare devices which are universally accessible using open standard network protocols.
2. Art Background
A variety of devices for obtaining medical information pertaining to patients are commonly employed in hospitals and clinics. For example, blood analyzers are commonly used in hospitals and clinics to obtain blood chemistry measurements such as glucose level. Other devices include devices for measuring heart rate, blood pressure, and devices for recording electrocardiogram data. Such devices are hereinafter referred to as healthcare devices. Such healthcare devices include portable devices such as portable blood analyzers, etc.
Prior healthcare devices commonly provide an access mechanism for transferring the medical information contained therein to a computer system. Such an access mechanism usually facilitates distribution of the medical information by taking advantage of the display and storage capabilities of a computer system.
The access mechanism of prior healthcare devices usually requires a computer system having a proprietary interface which is designed specially for the particular healthcare device. Typically, such a proprietary interface includes specialized software that executes on the computer system. Typically, a healthcare worker accesses medical information from such a prior healthcare device by transporting the healthcare device to the special computer system, attaching the healthcare device to a docking station or standard mechanism such as an RS232 port of the special computer system, and then initiating a transfer from the healthcare device using specialized software executing on the computer system.
Unfortunately, such prior methods of accessing healthcare devices are usually not well suited to out of hospital or out of clinic environments such as a patient's home where computer systems with proprietary interfaces are usually not available. Moreover, the costs associated with equipping a location such as a patient's home with a specialized computer system for accessing information from healthcare devices is usually prohibitively expensive.
Such limitations on the ability to access medical information in certain environments usually limits the utility of prior healthcare devices. For example, a visiting nurse may collect glucose data from a patient in the patient's home using a prior portable blood analyzer. Typically, the obtained glucose data remains stored in the portable blood analyzer until the visiting nurse returns to the hospital or clinic and manually initiates the transfer of the stored data to a special computer system. Unfortunately, a doctor cannot read the glucose data obtained with such a prior portable blood analyzer while it is in transit between the patient's home and the hospital.

Universally accessible healthcare devices with on the fly generation of HTML files


A method is described for operating a cellular network, where the cellular network uses a plurality of frequency division multiplexing (FDM) bands for wireless communication from user equipment (UE) to a base station (NodeB). At least one band-specific cell parameter is computed for at least one the plurality of FDM bands by a serving NodeB. The band-specific cell parameters are transmitted from the NodeB serving a first cell to a NodeB serving a second cell. The band-specific cell parameters may be computed in response to scheduling information and/or channel specific measurements made by the NodeB. A UE receives a first Power Configuration, a Second Power Configuration, and a Scheduling Message indicative of an FDM band from the set comprising at least from First FDM band and Second FDM band. The UE transmits with the First Power Configuration if the Scheduling Message was indicative of First FDM band, and with the Second Power Configuration otherwise.

Wireless cellular communication networks incorporate a number of mobile UEs and a number of NodeBs. A NodeB is generally a fixed station, and may also be called a base transceiver system (BTS), an access point (AP), a base station (BS), or some other equivalent terminology. As improvements of networks are made, the NodeB functionality evolves, so a NodeB is sometimes also referred to as an evolved NodeB (eNB). In general, NodeB hardware, when deployed, is fixed and stationary, while the UE hardware is portable.
In contrast to NodeB, the mobile UE can comprise portable hardware. User equipment (UE), also commonly referred to as terminal or mobile station, may be fixed or mobile device and may be a wireless device, a cellular phone, a personal digital assistant (PDA), a wireless modem card, and so on. Uplink communication (UL) refers to a communication between the mobile UE and the NodeB, whereas downlink (DL) refers to communication from the NodeB to the mobile UE. Each NodeB contains radio frequency transmitter(s) and the receiver(s) used to communicate directly with the mobiles, which move freely around it. Similarly, each mobile UE contains radio frequency transmitter(s) and the receiver(s) used to communicate directly with the NodeB. In cellular networks, the mobiles cannot communicate directly with each other but have to communicate with the NodeB. Embodiments of the invention, however, can be applied even beyond such cellular networks, since only concepts of wireless transmission and reception are needed. Nevertheless, the present invention will be described in the context of a cellular network.
Orthogonal Frequency Division Multiple Access (OFDMA) is a multi-user version of the popular Orthogonal Frequency-Division Multiplexing (OFDM) digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users. This allows simultaneous transmission from several users. Based on feedback information about the channel conditions, adaptive user-to-subcarrier assignment can be achieved. If the assignment is done sufficiently fast, this further improves the OFDM robustness to fast fading and narrow-band co-channel interference, and makes it possible to achieve even better system spectral efficiency. Different number of sub-carriers can be assigned to different users, in view to support differentiated Quality of Service (QoS), i.e. to control the data rate and error probability individually for each user. OFDMA is used in the mobility mode of IEEE 802.16 WirelessMAN Air Interface standard, commonly referred to as WiMAX. OFDMA is currently a working assumption in 3GPP Long Term Evolution downlink, named High Speed OFDM Packet Access (HSOPA). Also, OFDMA is the candidate access method for the IEEE 802.22 "Wireless Regional Area Networks".
NodeB is a term used in UMTS to denote the BTS (base transceiver station). In contrast with GSM base stations, NodeB uses WCDMA or OFDMA as air transport technology, depending on the type of network. As in all cellular systems, such as UMTS and GSM, NodeB contains radio frequency transmitter(s) and the receiver(s) used to communicate directly with the mobiles, which move freely around it. In this type of cellular networks the mobiles cannot communicate directly with each other but have to communicate with the BTSs
A NodeB can serve several cells, also called sectors, depending on the configuration and type of antenna. Possible configurations include omni cell (360°), 3 sectors (3×120°) or 6 sectors (3 sectors 120° wide overlapping with 3 sectors of different frequency).
The signals from different users within the same cell interfere with one another. This type of interference is known as the intra-cell interference. In addition, the base station also receives the interference from the users transmitting in neighboring cells. This is known as the inter-cell interference
Control information bits are transmitted, for example (in PUCCH), in the uplink (UL), for several purposes. For instance, Downlink Hybrid Automatic Repeat ReQuest (HARQ) requires at least one bit of ACK/NACK transmitted information in the uplink, indicating successful or failed circular redundancy check(s) (CRC). Furthermore, an indicator of downlink channel (CQI) needs to be transmitted in the uplink to support mobile UE scheduling in the downlink. While CQI may be transmitted based on a periodic or triggered mechanism, the ACK/NACK needs to be transmitted in a timely manner to support the HARQ operation. Note that ACK/NACK is sometimes denoted as ACKNAK or just simply ACK, or any other equivalent term. This uplink control information is typically transmitted using the physical uplink control channel (PUCCH), as defined by the 3GPP working groups (WG), for evolved universal terrestrial radio access (EUTRA). The EUTRA is sometimes also referred to as 3GPP long-term evolution (3GPP LTE). For said reasons, structure of the PUCCH provides for sufficiently high transmission reliability.
In addition to PUCCH, the EUTRA standard also defines a physical uplink shared channel (PUSCH), intended for transmission of uplink user data. The Physical Uplink Shared Channel (PUSCH) can be dynamically scheduled. This means that time-frequency resources of PUSCH are re-allocated every sub-frame. This (re)allocation is communicated to the mobile UE using the Physical Downlink Control Channel (PDCCH). Alternatively, resources of the PUSCH can be allocated semi-statically, via the mechanism of persistent scheduling. Thus, any given time-frequency PUSCH resource can possibly be used by any mobile UE, depending on the scheduler allocation. Physical Uplink Control Channel (PUCCH) is different than the PUSCH, and the PUCCH is used for transmission of uplink control information (UCI). Frequency resources which are allocated for PUCCH are found at the two extreme edges of the uplink frequency spectrum. In contrast, frequency resources which are used for PUSCH are in between. Since PUSCH is designed for transmission of user data, re-transmissions are possible, and PUSCH is expected to be generally scheduled with less stand-alone sub-frame reliability than PUCCH.

Network-based inter-cell power control for multi-channel wireless networks


A method for making multilevel electrical interconnections having a planar intermetal dielectric (IMD) with low dielectric constant k and good thermal conductivity was achieved. The method involves patterning an electrically conductive layer to form metal lines on which is deposited an anisotropic plasma oxide (APO) resulting in a thin oxide on the sidewalls of the metal lines and a much thicker oxide on top of the lines. A low dielectric constant (k) polymer is deposited and the polymer and APO are chem/mech polished back to the top of the metal lines. A fluorine-doped silicon oxide (FSG) is deposited, and via holes are etched to provide electrical connections for the next level of interconnections. The APO provides wider openings between metal lines filled with the low k dielectric polymer thereby reducing the RC time delay of the circuit. The thick top APO provides more processing latitude for polishing back the APO and low k polymer. The FSG provides a lower dielectric constant k for further reducing the RC delay and a better thermal conductivity constant K for minimizing the Joule heating when the circuit is powered up. The process can be repeated several times to form a planar multilevel interconnection for completing wiring on the integrated circuit.

(1) Field of the Invention
The present invention relates to a method for making integrated circuits on semiconductor substrates, and more particularly to a method for forming multilevel wiring on substrates with insulators having a low dielectric constant that reduce the RC time delays. The method is particularly useful for interconnections on ULSI circuits with minimum feature sizes less than 0.5 micrometers (um).
(2) Description of the Prior Art
Integrated circuits fabricated on semiconductor substrates for Ultra Large Scale Integration (ULSI) require multilevels of metal interconnections for electrically interconnecting the discrete semiconductor devices on the semiconductor chips. In the more conventional method the different levels of interconnections are separated by layers of insulating material. These interposed insulating layers have etched via holes which are used to connect one level of metal to the next. Typically, the insulating layer is a silicon oxide (SiO.sub.2) having a dielectric constant (relative to vacuum) of about 4.1 to 4.5. However, as the device dimensions decrease and the packing density increases, it is necessary to reduce the spacing between the metal lines in the interconnections to effectively wire up the integrated circuits. Unfortunately, as the spacing decreases, the intra- (on the same metal level) and interlevel (between metal levels) capacitances increase between metal lines when an insulating layer having the same dielectric constant is used since the capacitance C is inversely proportional to the spacing d between the lines (C=keA/d where k is the dielectric coefficient, e is the permittivity of the insulator, A is the area, and d is the spacing between lines). Therefore, it is very desirable to minimize the dielectric constant k in the insulator (dielectric) between the conducting lines to reduce the RC time constant and thereby increase the performance of the circuit (frequency response) since the signal propagation time in the circuit is adversely affected by the RC delay time, where R is the resistance of the metal line, and C is the inter- and/or the intralevel capacitance mentioned above. The dependence of delays due to the gate delays and the interconnects are shown in FIG. 1 reported at the International Symposium on VLSI, TSA, 1995, page 164. As shown in FIG. 1, the curve 1 shows the time delay in nanoseconds of the FET gate minimum feature size (channel length) in um (gate delay) and the curve 2 shows the interconnect delay as a function of the minimum feature size (line spacings). It is clearly seen that as the minimum feature size is reduced below 1.0 um, the interconnection delay (curve 2) becomes the predominant circuit delay. For example, below 0.5 um the gate delay (curve 1) decreases to about 0.1 E-9 seconds while the interconnect delay 2 increases rapidly to about 2.5 E-9 seconds.
One approach to minimize these RC time delays is to use a good electrical conductor for the interconnections, such as replacing aluminium with copper to reduce resistance R, and in addition to use an insulating material that has a lower dielectric constant k, such as an organic, to reduce the capacitance C between lines. The improvement in the interconnect delay can best be understood by the family of curves in the prior art of FIG. 2 (Proceedings from the International Electronic Device Meeting (IEDM), 1995, page 244). The RC expression for a metal line L with a pitch of P and a metal thickness T and an intermetal insulating layer also having a thickness T is given by RC=2pke.sub.o (4L.sup.2 /P.sup.2 +L.sup.2 /T.sup.2), where p is the metal resistivity, k is the relative dielectric constant, and e.sub.o is the permittivity in vacuum. The family of curves is shown for the interconnect RC time delay in nanoseconds (abscissa) as a function of metal thickness in micrometers (ordinate axis) for a metal line pitch of 0.8 um and having 10 mm lengths. FIG. 2 shows the rapid increase in the interconnection delay (nsec.) as the metal thickness T is decreased for a constant pitch P and a metal length L of 0.8 um. The curve 3 is for aluminum (Al) lines having an intralevel dielectric constant k of 4, such as an undoped silicon oxide (SiO.sub.2), while curve 4 shows the improvement in delay for comparable patterned copper lines using an insulator having the same dielectric constant k of 4. Curves 5 and 6 show comparable improvement in the delay time for Al and Cu, respectively, using a low k interlevel dielectric of k=2, such as an organic polymer. For example, a number of inorganic and organic dielectrics are listed in TABLE I that can be used to reduce the RC delays.
TABLE I ______________________________________ DIELECTRIC CONSTANT ______________________________________ INORGANICS PLASMA SIO.sub.2 4.1-4.5 FLUORINE-DOPED SIO.sub.2 3.5 ORGANICS POLYIMIDE 3.0-3.7 POLYSILSEQUIOXANE (Si POLYMER) 2.7-3.0 BENZOCYCLOBUTENE (BCB) 2.7 PARYLENE N 2.7 FLUORINATED POLYIMIDE 2.5 PARYLENE F 2.3 AMORPHOUS TEFLON 1.9 ______________________________________
To better understand the problems associated with using a low dielectric polymer, FIG. 3 is shown having closely spaced metal lines 16 formed on a substrate 10 having a silicon oxide layer 12. A conformal chemical vapor deposited liner 18, such as silicon oxide, is deposited by low temperature chemical vapor deposition (CVD) to protect the metal lines from the low k polymer that typically has high moisture content. The CVD lines also serve to improve the adhesion of the low k polymer 20 which is then deposited. Typically a low dielectric polymer is deposited and planarized to provide an intermetal dielectric (IMD) layer. A hard mask 22 composed of a low temperature CVD is deposited and a photoresist mask 24 is then patterned to form the via holes in the hard mask and in the low k polymer. Typically there are several problems associated with this structure. One is the ability to control the chemical/mechanical polishing of the polymer to the top of the metal lines 16. Other problems are non-standard via hole etch, outgassing of moisture such as H.sub.2 O in the via holes that can cause via poisoning, which can erode the next level of aluminum contacts, and low dielectric breakdown strength and high electrical leakage currents. The low k polymer also has the issue of a low mechanical strength and poor dimensional stability. Another concern is poor thermal stability (<450.degree. C.) that can be exacerbated by the Joule heating of the metal lines from high current density and poor thermal conductivity K of the polymers. For comparison the thermal conductivity of polymers such as polyimide, SOP (spin-on polymer), and HSQ (Hitachi Chemical polymer) are compared with the inorganic oxides plasma-enhanced PETEOS and high-density plasma (HDP) CVD in TABLE II.
TABLE II ______________________________________ Thermal Conductivity Film Thickness Dielectric Film K(mW/cm.degree. C.) (um) ______________________________________ PETEOS 11.5 0.1-3.8 HDP CVD Oxide 12.0 1.0-1.8 Polyimide 2.4 3.3-9.0 SOP 2.4 0.34-0.5 HSQ 3.7 0.27-0.38 ______________________________________
As can be seen the oxides have a thermal conductivity K as measured in milliWatts/cm.sup.o C which is about 4 to 6 times better than the polymers.
Several methods for forming planarized interconnections using low dielectric constant insulators have been described. For example, Jeng, U.S. Pat. No. 5,486,493, describes a method for forming closely spaced Al or titanium nitride/Al/titanium nitride interconnect lines having a low dielectric constant insulator between metal lines. Another method for making sub-micron metal interconnections using a spin-on glass (SOG) is described by Chen et al., U.S. Pat. No. 5,366,850, in which the SOG is cured and partially etched back to an insulating liner on the metal lines to form a planar surface. A CVD oxide is then deposited and contacts are etched to the metal lines without exposing the SOG. Chen et. al., in the Japanese Journal of Applied Physics, Vol 32 (1993) pp. 6119-6121, entitled "The Anisotropic Plasma-Enhanced Chemical Vapor Deposition SiO.sub.2 /Spin-on Glass Process for 0.35 um Technology" teaches a method for forming an intermetal dielectric for sub-micrometer metal interconnections.
As the spacings between interconnecting metal lines are further reduced, such as in future 0.18-0.13 micrometer technologies, it becomes increasingly difficult to provide an insulating layer having a low dielectric constant between adjacent metal lines and further to provide good thermal conductivity for cooling the circuit. There is also a need for providing a process with greater latitude for forming a planar low k dielectric layer, which is free of poisoned via holes (outgassing problems) that can degrade the metal contacts. Therefore there is still a strong need in the semiconductor industry for providing a simplified method for forming multilevel metal interconnections having reduced inter- and intralevel capacitance to reduce the RC time constant that improves circuit performance.

Method for fabricating intermetal dielectric insulation using anisotropic plasma oxides and low dielectric constant polymers

Industrial Technology Research Institute


A tracked vehicle includes a pilot control module which enables the pilot to steer the tracked vehicle using an existing joystick of the tracked vehicle. The tracked vehicle also includes a dual track drive pedal which drives the tracks of the vehicle simultaneously. The joystick is used to make steering corrections when utilizing the dual track drive pedal.

In underground pipe lying operations, a trench is typically dug, and then sections of pipe are placed therein. In many cases, the length of these sections of pipe is such that multiple construction vehicles such as tracked vehicles are used to place the section of pipe into the trench. The tracked vehicles are typically tracked vehicles with a boom. The boom itself operates in much the same way as a crane in that the pipe is suspended from the boom using specialized pipe carrying means.
As mentioned above, several of these vehicles carry a section of pipe simultaneously. These vehicles slowly lower the section of pipe together into the trench. Because the section of pipe is a rigid structure, the tracked vehicles must move in a synchronized manner. If one vehicles motion is not carefully synchronized the remaining vehicles, the section of pipe can undesirably swing while being carried, can be placed insufficiently in the trench, or worse, may become damaged.
Unfortunately, it is not uncommon for the above undesirable scenarios to unfold. Circumstances can vary, but typically one of the several tracked vehicles moves in an undesired direction off of its intended path due to uneven ground or disturbances. Operators try to correct this but due to the existing steering mechanism in such vehicles, such corrections are difficult to make.
Indeed, these vehicles typically utilize a dual pedal steer system. One pedal controls one of the pair of tracks of the vehicle, and the other pedal controls the other one of the pair of tracks. As is readily known by those in the industry, steering of such tracked vehicles is primarily effectuated by causing one of the pair of tracks to travel at a different speed than the other resulting in a turn in direction to the left or to the right. Making very fine adjustments with such a dual pedal configuration is difficult. Further, making very quick adjustments to right an off course vehicle is also very difficult, especially when carrying a section of pipe.
Efforts have been made to address the above. For example, more modern tracked vehicles used in pipeline applications may use a single pedal mode. In single pedal mode, a separate, single pedal may be used to drive both tracks simultaneously at the same speed. While such a configuration ensures an even speed, all steering functionality is removed. In other words, as the tracks move together, if one track encounters a rock or other encumbrance, its speed relative to the other may be effected. This will cause a slight turn. In single pedal mode, the operator cannot rectify or counteract this slight turn. Ultimately, the above problems will then persist.
Accordingly, there is a need in the art for a tracked vehicle and associated steering system which alleviates above. The invention provides such a vehicle and steering system. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.

Tracked vehicle with steering compensation


An adaptive multi-bit delta and sigma-delta modulation and demodulation technique, wherein a one-bit modulator generates a binary output signal from an analog input signal and a multi-bit adapter for generating a scaling signal for scaling a step-size of the sigma-delta modulator.

1. Field of the Invention
The present invention relates to analog-to-digital converters, and in particular, to a structure for adaptive multi-bit delta and sigma-delta modulation.
2. Description of the Related Art
(Note: This application references a number of different publications as indicated throughout the specification by reference numbers enclosed in brackets, e.g., [x]. A list of these different publications ordered according to these reference numbers can be found below in the Section entitled "Publications" in the Detailed Description of the Preferred Embodiment. Each of these publications is incorporated by reference herein.)
The signal-to-noise (SNR) performance of the source coder varies with the strength of the input signal. In pulse code modulation (PCM), for example, the SNR is proportional to the ratio V/σx where V is the full scale amplitude of the coder and σx is the standard deviation of the input signal. Waveform coders are also expected to have good dynamic range performance, i.e., to have high SNR even for small input strength. It is well-known that log-PCM (e.g., μ-law and A-law PCM) improves the dynamic range of the coder by reducing, but not eliminating, the dependence of SNR on the ratio V/σx. Another method to increase the dynamic range of coders is to use adaptive delta modulation (ADM) and adaptive sigma-delta modulation (ASDM) systems. See, for example [1]-[6] for overviews on data converters and their applications. Still, conventional ADM and ASDM systems tend to be one-bit coders and their performance is therefore limited by this fact.
In previous works [7, 8], two adaptive delta and sigma-delta modulation schemes have been proposed. While these schemes still employ single-bit quantization, they were nevertheless shown to exhibit superior tracking performance, high dynamic range and improved SNR compared to other similar schemes. Of course, one way to further improve their performance would be to increase the number of quantization bits.
Doing so will decrease quantization noise and increase the overall SNR. However, in the process of this modification it is useful to make a distinction between quantization bits inside a main loop of a modulator and quantization bits inside an adapter that is used to adapt the step-size of the modulator. The present invention maintains the quantization within the main loop to one bit, but increases the quantization within the adapter to multiple bits in a manner that results in improved performance.
Specifically, the present invention describes adapters using multi-bit modulation, including a companded differential pulse code modulator, an adaptive sigma-delta modulator, an adaptive delta modulator, and adaptive differential pulse code modulation. The present invention also describes a framework for studying the performance of these adapters by showing how they can modeled in terms of first-order random gain models. Performance measures are derived from these simplified models and simulation results are then used to illustrate a good match between theory and practice.

Adaptive multi-bit delta and sigma-delta modulation

The Regents of the University of California


An uninterruptible power supply comprises a power source (250) and a housing (110) to contain the power source. The housing comprises an outer surface (111) in which are located a recess (121) and a flat region (231). An electrical outlet (241) is located at the flat region, and a light source (130) is removably housed in the recess. The power source is capable of supplying electric power to the electrical outlet in response to a condition external to the uninterruptible power supply.

Uninterruptible power supplies have been developed to supply backup power in the event of an interruption in the mains power supply. In general, uninterruptible power supplies contain a power source such as a battery that is capable of operating independently of the mains power supply, and that is further capable of supplying electric power to electronic devices and the like. Typically, an uninterruptible power supply routes mains power through the battery and to the electrical outlet during normal operation of the mains power supply, thereby charging the battery, and automatically switches to battery power during a mains power outage or other interruption in mains power.
Because uninterruptible power supplies are designed to perform particular functions during power interruptions, it follows that the performance of such functions may often take place in a dimly lit or darkened area. Accordingly, there exists a need for an uninterruptible power supply that is capable of enhancing visibility in the area in which the uninterruptible power supply is located.
For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements.
The terms "first," "second," "third," "fourth," and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprise," "include," "have," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
The terms "left," "right," "front," "back," "top," "bottom," "over," "under,"in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. The term "coupled," as used herein, is defined as directly or indirectly connected in an electrical, mechanical, or other manner.

Uninterruptible power supply and method of manufacturing same


Provided are techniques for comparing a first fileset associated with a first operating system (OS) with a second fileset associated with a second OS; determining, based upon the comparing, that the second OS is a more current version of the first OS; in response to the determining that the second OS is a more current version of the first OS, moving, in conjunction with live application mobility, a virtual machine (VM) workload partition (WPAR) on the first LPAR to a second LPAR, the moving comprising determining a set of overlays associated with the WPAR corresponding to the second OS; removing from the WPAR any overlays associated with the first OS; applying to the WPAR a set of overlays corresponding to the second OS; check pointing processes associated with the WAPR; and copying live data associated with the LPAR from the first LPAR to the second LPAR.

Unlike logical partitions LPAR s), in which computing resources are partitioned with respect to hardware, a virtualized file system is partitioned with respect to software. In addition, although LPARs which may have different operating systems, virtualized file system spaces typically include virtualized operating system (OS) environments within a single instance of an OS, an example of a virtualized file system space, used as an example throughout this Specification, is a workload partition (WPAR). It should be understood that although the claimed subject matter is described with respect to WPARs, the same principles also apply to other types of virtualized file system spaces.
Basically, there are two types of WPARs, system WPARs and application WPARs. Typically, a system WPAR partitions system resources and an application WPAR isolates and executes one or more application processes. The following description is based upon system WPARs. Each WPAR has a regulated share of system resources and may have unique networks and file systems. In addition, each WPAR may have separate administrative and security domains, with each WPAR having a unique root user, regular users and passwords, its own services such as inetd, cron and syslog, and can be stopped and started on its own. A WPAR does not typically share writable file systems with other WPARs or the global system. WPARs share an operating system and may share underlying file systems, real or virtual disk adapters, processors, memory, paging space and a real or virtual network card.
Although WPARs with in a particular LPAR share one OS, different WPARs within a LPAR may run different versions of a particular OS. Such a WPAR is called a "versioned" WPAR. A versioned WPAR typically runs an older version of an OS than the global LPAR. The versioned WPAR contains commands, shared libraries, and so on of whatever level of OS it is running. However some commands, such as, but not limited to, device drivers and other kernel extensions, within a versioned WPAR are "overlaid," which means that the WPAR runs the corresponding command in the global LPAR. Typically, this is necessary to keep certain commands in sync with the kernel on the global LPAR because WPARs do not include their own kernel.
When a file is overlaid, the file is renamed, typically by adding a suffix to the name and the original file, or legacy binary, is replaced by a symbolic link to a copy of the native runtime execution wrapper. Typically, there is one copy of the native execution wrapper for each target binary's directory path. In addition, actions are taken to reflect these changes in data that an install facility use to track the state of all installed files on the system and references to the original name are replaced by the new name with the added suffix. The wrapper mechanism works as follows: 1) The path of the native library is pre-pended to the LIBPATH parameter; 2) The name of the executable that invoked the wrapper is identified; and 3) A special new "native runtime exec( ) interface" is called to execute the corresponding native binary.

This patent is subject to a terminal disclaimer.

Live application mobility from one operating system level to an updated operating system level and applying overlay files to the updated operating system

International Business Machines Corporation


There is provided a system and a method for quantitative measurement of spasticity in a patient. It has been found that stretch reflex measurements, that are quantitatively indicative of spasticity, can be obtained by recording an EMG signal while the limb is being moved at a variety of angular velocities. The method advantageously allows the clinician to perform the test at the bedside by eliminating the need for cumbersome mechanical components for moving the limb while providing quantitative measurements.

Spasticity is a neurological symptom affecting children and adults causing an abnormal increase in muscle tone that occurs when the affected muscle is stretched. Spasticity can occur in neurological disorders that damage the parts of the brain and the nervous system that control voluntary movements. The most common disorders leading to spasticity are cerebral palsy, spinal cord injury, multiple sclerosis, stroke, and traumatic brain injuries, due to a lack of oxygen, physical trauma, haemorrhage, or infection. Some of these injuries can occur at birth and others can occur during adulthood.
The severity of spasticity can range from slight muscle stiffness to deformity and permanent muscle shortening, called contracture. Spasticity often interferes with voluntary movement and with the proper positioning of the body. The presence of spasticity interferes with the accomplishment of activities of daily living such as dressing, eating, and grooming. Spasticity also interferes with mobility, seating and transfers such as moving from the bed to the wheelchair or from sitting to standing. Spasticity also may make it difficult to sit comfortably, or to change positions frequently enough to prevent joint pain and pressure sores. Spasticity in the feet can prevent comfortable fitting of shoes. Severe spasticity may cause painful joint misalignments and limitations in joint movement interfering with hygiene.
Physical, pharmacological and surgical therapies are aimed at decreasing spasticity and restoring motor control. Physical treatments include stretching and positioning to prevent the development of muscle contractures. Pharmacological approaches include oral or intrathecal delivery of drugs targeting the neuromuscular junction of the muscle or the synaptic pathways and nerves innervating the muscle. Local injections of drugs that weaken or paralyze overactive muscle (chemodenervation agents) can be effective for spasticity in isolated muscles. Severe spasticity that cannot be effectively treated with drugs or injections may respond to surgical destruction of some overactive nerves in the spine. Contracture may be treated with serial casting to allow tendons to stretch, or orthopedic surgery if required.
A major problem in the treatment of spasticity is that a sensitive measure of the phenomenon that can be applied at the bedside or in the clinic to make treatment decisions and to judge the effectiveness of treatment does not yet exist. Until now, a variety of different clinical measures have been used to assess spasticity. The current 'gold standard' is a 5 point scale (Ashworth Scale) that can only distinguish the presence or absence of spasticity but is not sensitive to its severity. What is more, the scale is subjective, so that the evaluator must 'judge' how much resistance is felt when he or she stretches the muscle. Clinicians and researchers agree that this measure is inadequate since it does not discriminate between different types of hypertonicity and does not adequately reflect the severity of spasticity. Furthermore while apparatuses exist for obtaining spasticity measurements that use mechanical components to apply a torque to a joint, they are cumbersome and difficult to adapt to the various types of joints and may create discomfort in the patient.
The identification of the need to have a better (more sensitive and discriminative) measure of spasticity that is easily accessible to the clinician has been apparent for many years.

Method and apparatus for determining spasticity


A system and method capture data from an SS7 network and pair each invoke message with its corresponding response message. Each message is stored in a daily file as well as in a table dedicated for that particular message type. A separate file is also maintained on each MIN and holds the most current registration information for each MIN. The system and method support four different types of queries: a MIN/ESN query, an active roamer query, a switch-to-switch query, and a transaction statistics query. The MIN/ESN query provides roaming activity on a specific MIN or ESN while the active roamer query provides information on all roamers in a serving market. The switch-to-switch query reveals messaging at one switch or between two switches. The statistics query provides data to a provider on all of its subscribers roaming in foreign networks or on all phones within its own network. The system has a Graphical User Interface (GUI) for displaying information on each message in an easy and convenient manner. The details of a record are displayed in a tabular format with each tab holding data for a group of parameters.

The present invention relates in general to the field of telecommunications and in particular to the field of wireless telecommunications systems administration, fraud detection, customer service, engineering support, and technical support.
The market for telecommunications services has grown at an extraordinary pace, and perhaps the greatest growth has occurred in the market for wireless communications, including cellular networks and personal communication systems.
Conventional wireless telecommunication systems employ numerous independent cellsites (xe2x80x9ccellsxe2x80x9d). Each cell covers a designated geographic area and is connected via a dedicated network (usually leased lines or microwave) to a Mobile Switching Center (xe2x80x9cMSCxe2x80x9d) that is in turn connected to the Public Switched Telephone Network (xe2x80x9cPSTNxe2x80x9d). The MSC handles all call processing intelligence, switching functionality, fault detection and diagnostics. MSCs are also integral to the operation of recently developed Personal Communication Systems (xe2x80x9cPCSsxe2x80x9d), another type of wireless system. A PCS utilizes numerous xe2x80x9cmicrocellsxe2x80x9d that blanket a high use area, or an area where terrain features limit transmission capabilities (e.g., a downtown office district with tall buildings.) Because of the greater number of cells, the PCS can handle a significantly greater volume of traffic. Located within each PCS microcell is a low power transmitter. After receiving the subscriber""s signal, the low power transmitter communicates (normally via microwave, PSTN, or data lines) with a controller. The controller, in turn, communicates with the MSC. Each PCS or cellular network covers only a specified xe2x80x9chomexe2x80x9d geographic area. Consequently, as the mobile user moves out of the home area and into a xe2x80x9cforeignxe2x80x9d area, telecommunications service is provided by a xe2x80x9cforeignxe2x80x9d wireless service provider typically not associated with the user""s home wireless service provider. Operation in a foreign area is known as xe2x80x9croaming.xe2x80x9d
The deployment of Signaling System Number 7 (xe2x80x9cSS7xe2x80x9d) networks for wireless systems like PCS or cellular networks has permitted carriers to supply a number of new applications to wireless systems"" customers. SS7 is a highly flexible common channel signaling standard specifically designed for providing circuit and database related message flow control in networks. The feature enhancements to services made possible SS7 have accelerated its deployment. But most cellular systems continue to use services furnished by outside network providers. The high price of those services has tended to lead wireless services providers to deploy their own SS7 networks.
The fees associated with the use of network services provided by third parties, which may be charged on a per transaction basis, lead to higher consumer prices for wireless communications services. The cost of paying network providers to operate a SS7 or other network, and the consumer prices they result in, may represent a serious constraint on wireless growth. An additional impediment to growth in the market for wireless services is the absence of a seamless roaming environment. In a seamless roaming environment, enhanced communications services are provided to mobile subscribers as they move about the nation (or, more optimistically, through various parts of the world), without diminution in service as one crosses boundaries between service providers.
Fraudulent uses of wireless systems pose an even greater threat to growth of wireless communications. For example, industry fraud losses exceeded an estimated four hundred million dollars in 1994.
Geographic expansion of services permitted by the creation of a nationwide network has accelerated the already significant cellular fraud. The incidence of fraud has significantly worsened as carriers allow users to make calls from anywhere in the country. Losses for 1995 are estimated at over one and a half million dollars per day. Growth in fraud losses for the first time exceeds industry growth.
Indeed, some wireless service providers have been forced by the overwhelming costs of fraud to suspend roaming service in foreign areas where its incidence is high. Preventing or minimizing the fraudulent use of wireless systems is therefore a necessary precondition to putting the industry back on a solid growth track and developing a nationwide network providing seamless roaming.
Two types of fraud are prevalent. One is xe2x80x9ccloning fraud,xe2x80x9d in which a valid customer""s mobile identification number (xe2x80x9cMINxe2x80x9d) and/or electronic serial number (xe2x80x9cESNxe2x80x9d) are xe2x80x9cclonedxe2x80x9d or copied into another cellular set. Most typically, cloning fraud is perpetrated in a foreign service provider""s network. Even when the fraud occurs outside of the home service provider""s network, the home service provider remains liable for the fraud, the costs of which directly diminish the service provider""s revenue.
A second typical fraud problem involves subscribers who are not entitled to service (e.g., because they have failed to pay their bills or obtained service under false identities, etc.), but who nevertheless attempt to obtain roaming service in a foreign service provider""s wireless system. Roaming involves a validation process to determine if the roamer is legitimate in its home system. The switches of systems located geographically close to one another are often coupled because those systems"" customers will frequently roam into the adjacent area. These systems can directly communicate with one another to exchange validation requests and fraud control data. In any event, even if some switches of different systems were coupled, those switches may nevertheless be unable to communicate with one another to exchange validation requests and fraud control data for the simple reason that the switches may be incompatible with one another. As a result, a national clearinghouse system for handling fraud and roamer management has arisen.
A national clearinghouse typically has a database containing so called xe2x80x9cnegative filesxe2x80x9d including lists of stolen phones and cloned MINs. The typical clearinghouse also couples to the MSCs of subscribing systems in order to access subscriber data, usually called the HLR or Home Location Register, to validate subscribers for whom services are being requested in a foreign market whose service provider is also a member of the clearinghouse network. A national clearinghouse is capable of providing on-line support as well as a data feed. The clearinghouse validates customers prior to allowing a request for telecommunications service to proceed. But by the time the clearinghouse checks its own database and then, if necessary, the database of the subscriber""s carrier, the foreign carrier may already have permitted a fraudulent roaming communication to occur.
In order to detect xe2x80x9ccloning fraud,xe2x80x9d a service provider may use, among other methods, a fraud management system that develops usage profiles. These profiles are based on the communications traffic information for particular customers and are obtained from billing records and other sources. If a call does not match the customer""s profile, an analyst may contact the customer. A fraud detection system (like CloneDetector available from GTE TSI (Telecommunications Services Inc.)) analyzes calling patterns to identify calls made close in time using identical MINs in widely-separated geographical areas. This type of condition generally indicates that one of the MINs is a clone. The customer corresponding to the MIN is contacted for confirmation and appropriate steps are taken to lock the clone out of the system.
Some clearinghouses are presently attempting to offer both fraud detection systems and customer on-line support systems intended to react in real time. Clearinghouses charge each subscribing service provider a per-transaction fee for providing fraud management services and also charge for certain on-line support data. In addition to charging transaction fees, clearinghouses incorporate each subscribing service provider""s valuable and commercially sensitive customer information into a central pool within its exclusive control. Clearinghouses provide needed roamer visibility. But subscribing service providers lose the ability to obtain data on their own network transactions if they choose not to utilize the clearinghouses for validation for particular transactions. Data of this sort is critical, not only for network operation, but also for purposes of planning and marketing. Understandably, subscribing service providers also prefer to maintain control over their own customer profile and system traffic information. They thus prefer to eliminate the clearinghouse service and directly manage user validation for their own networks in order to eliminate the transaction fees charged by the clearinghouses and obtain their own on-line support data.
Subscribing service providers can circumvent the clearinghouse services by networking their switches with switches in foreign service providers"" systems. This process is facilitated by deployment of SS7 networks, coupled with the advent of IS-41. IS-41 is an interim standard created by the Electronic Industry Association/Telecommunications Industry Association (xe2x80x9cEIA/TIAxe2x80x9d) that permits switches produced by different manufacturers to communicate with one another. IS-41 enables the switch of a home system of a roaming subscriber to communicate with a foreign system providing services to the roaming subscriber in order to transmit validation and customer profile information. IS-41 messages may be transported over SS7 networks that many service providers are already connected with or soon will be deploying. Other standards may be developed and will likely also be capable of transmission over SS7 networks. Using such standard message formats and protocols, switches belonging to differing service providers become capable of requesting validation data and exchanging customer profile information. This information sharing not only eliminates the high transaction charges associated with a national clearinghouse, but it also returns control of valuable, proprietary customer profile information to the service providers.
Since many such fraud detection systems (such as GTE""s) obtain fraud control and customer support data feeds from links between an individual MSC and clearinghouse, as wireless service providers connect their switches directly using SS7 or another network, the data traffic occurring between such interconnected switches is no longer xe2x80x9cvisiblexe2x80x9d to the clearinghouse system. In other words, clearinghouse systems often cannot obtain information on transactions involving wireless service providers whose switches are coupled directly to each other via the SS7 network.
Obviously, this is a problem that directly impedes clearinghouses ability to provide accurate and comprehensive fraud control and customer support data. The problem will accelerate as more service providers interconnect via SS7 or other networks. Such interconnections will increase as service providers take advantage of the flexibility of the SS7 network and new standards like IS-41 in order to interconnect directly with other service providers in adjacent geographic regions or in high use metropolitan areas frequented by business or tourist travelers.
Further, with the advent of SS7 networks, future service enhancements are likely. Those enhancements should be provided without disrupting fraud data feeds and other customer service operations; current systems do not eliminate or minimize disruptions, however.
As wireless service providers link their switches and move toward a nationwide network, xe2x80x9cthey will bypass the traditional methods of capturing roamer messages. They will have to assume more responsibility for insuring that the systems they use provide the required level of message visibility to maintain superior customer service and roamer managementxe2x80x94especially as more customers are roaming and using additional enhanced services.xe2x80x9d Rolando Espinosa, xe2x80x9cThe Industry""s Most Important Challenge: Cellular Signaling Network Management,xe2x80x9d Telephony, Vol. 227 at 27 (Aug. 22, 1994.) The ongoing and projected future conversion to SS7 networks therefore requires new methods and systems to extract fraud control and customer support information.
Even for service providers that may not adopt the SS7 or other standard network protocols, fraud control and customer on-line support systems furnished by outside providers suffer from drawbacks, both technical and financial. Among their technical shortcomings, the systems may not provide the full fraud data feeds necessary for minimizing and managing network fraud. Nor do the systems provide complete message xe2x80x9cvisibilityxe2x80x9dxe2x80x94information on transactions with some of the carrier""s closest roaming partners may not be obtained and transmitted to either the fraud control or customer support systems. Financially, reliance on outside network providers for fraud control and customer support systems costs service providers significant ongoing transaction fees.
Service providers face other difficulties which are only aggravated as they interconnect their switches to the switches of other service providers. Customer service, for example, is one aspect of operating a wireless network that becomes more of a challenge when subscribers roam into other service areas. Even when a subscriber has difficulty within the service provider""s home network, isolating the source of the problem may take days or even weeks. The problem, for instance, could be with the subscriber""s phone, with a particular switch within the provider""s network, with the subscriber""s billing system, or with a Home Location Register (HLR). Locating the problem is often accomplished through a process of elimination. When the problem occurs when the subscriber is roaming, the possible sources of the fault are compounded and additional time and expense may be incurred before the problem can be detected and corrected.
The difficulty in providing customer service is endemic of a larger difficulty in maintaining a service provider""s network. Even when the source of the problem is known, such as a particular switch within the network, identifying and correcting the precise problem is often not an easy task. For a switch, the service provider must dispatch personnel to the switch so that they can monitor the operations of the switch. The personnel then try to replicate events that triggered the problem or fault in the hopes that they can detect the source of the fault. In general, the engineering and technical support personnel react to the problems and are often unable to stop problems before they occur. Additionally, the engineering and technical support personnel attempt to isolate and correct problems by monitoring future activity of the network and do not have clear records as to what occurred in the past at the time of the problem.
As discussed above, the advent of IS-41 allows greater communication between switches, especially between switches of two different service providers. The IS-41 messages transmitted and received by a service provider contains information about its network and subscribers and can be extremely valuable to the service provider. The service provider, however, is typically unable to capture the value in these messages since a single service provider have hundreds of thousands of these messages passing through its network each day. With such a large volume of messages, a service provider cannot easily extract useful information from the messages and the potential value in the messages is not captured.
According to one aspect, the present invention provides apparatus and methods for capturing information relating to communications traffic from one or more wireless telecommunications systems, and for processing the captured information at a message processor to produce roamer visibility and fraud data useful in administering such systems. A monitoring and data capture platform or subsystem monitors each of the telecommunications links coupling a Mobile Switching Center (xe2x80x9cMSCxe2x80x9d) or network elements like Signal Transfer Points or particular types of MSCs directly. This data capture subsystem may be configured to capture selected data pertaining to wireless telecommunications, including any number of desired call control and processing messages, depending on the type of data desired for roamer visibility, fraud control engineering, customer support or other functions of importance to wireless service providers, whether they provide cellular, PCS or other wireless communications network services. The selected data, typically in the form of messages in an operative protocol (e.g., the IS-41 protocol), can then be buffered for analysis or transmission. The selected data can be formatted and transmitted to (1) a message processor subsystem for further processing or (2) directly to a fraud system, customer support system, or other administrative instrumentality for further analysis or use.
Similarly, a method associated with the data capture apparatus furnishes visibility and/or fraud data relating to wireless communications based on related message traffic. Signals pass through various network elements like a Signal Transfer Point (xe2x80x9cSTPxe2x80x9d) pair or switch and are transmitted over at least one telecommunication network link coupled to at least one wireless switching center. A data capture device is coupled to at least one of the links or one of the network elements. Links or network elements are monitored for messages of interest, such as a message belonging to a preselected (and changeable) set of message types.
According to the method, signals containing messages relating to wireless telecommunications traffic are read off of at least one of the telecommunications links. Messages pertaining to wireless traffic are identified, and, of these messages, those belonging to a preselected (but changeable) set of message types are selected. Selected messages are then forwarded to an administrative instrumentality. The administrative instrumentality may be a message processor that further processes messages received from a plurality of data capture devices to collate messages or filter out from the incoming data stream messages redundant to those already provided by an outside source. Alternatively, message processing can be done at the data capture device and messages forwarded directly to other administrative instrumentalities like a fraud detection system, customer on-line support station or any other end-user capable of operating upon the captured messages.
In an illustrative embodiment of a system according to the present invention, the data capture subsystem is configured to transmit the selected data to a message processor for further processing to yield useful visibility and fraud data. (Generally, xe2x80x9cvisibility dataxe2x80x9d is wireless system data that identifies subscriber roaming activity between wireless systems. An example of some of the visibility data generated is the location and system usage of roaming subscribers.) The message processor stores selected incoming messages from the data capture subsystem in a memory location. The message processor then collates received messages with the stored messages to provide roamer visibility, fraud, or other useful administrative data. This data may be made available for query by on-line customer support workstations that may display the forwarded data on a real-time basis. Additionally, the message processor processes incoming captured messages and extracts certain data for transmission to a fraud detection or control system in the form of a data feed, for example.
A data capture portion of an embodiment of the present invention thus generates a set of wireless telecommunications visibility and/or fraud data based on messages transmitted over at least one telecommunications link or through various network elements. The visibility or fraud data is for use by an instrumentality in monitoring, servicing or otherwise administering a wireless telecommunications system.
One embodiment of a data capture apparatus comprises a link capture device that includes at least one telecommunications link interface; each link interface corresponds and couples to a telecommunications link for reading signals off the link. A processor may be coupled to the link interface and may be programmed for any of the following tasks: retrieving signals read by the telecommunications link interface; identifying messages in the retrieved signals; selecting messages belonging to a preselected set of message types of interest; and formatting the selected messages for transmission to the administrative instrumentality.
Alternative embodiments of data capture apparatus exist for capturing messages of interest from message traffic in wireless systems.
For example, rather than read messages off of telecommunications links, message traffic through a Signal Transfer Point (xe2x80x9cSTPxe2x80x9d) can be directly monitored and messages of interest captured. Preprocessors provided for each of a pair of STPs read appropriate message traffic and, after reformatting, forward selected captured messages to a merge processor. The merge processor combines captured messages and forwards them to the message processor.
Alternatively, for MSCs (particularly those manufactured by ATandT) operating with a proprietary protocol (ATandT""s protocol is called EFTN) the proprietary intra-switch messages can be xe2x80x9ctranslatedxe2x80x9d to a standard format (e.g., IS-41). A switch message capture device, implemented in a separate processor or resident on a portion of the message processor, can obtain from the switch xe2x80x9ctranslatedxe2x80x9d proprietary messages corresponding to messages of interest passing through, translated at and buffered at the switch. (To translate EFTN a software package may be obtained from ATandT and deployed at the switch of interest.) Captured messages are then transferred to an appropriate other portion of the message processor. (Absent this alternative embodiment of data capture device, messages in ATandT""s proprietary EFTN format would not be captured since other data capture devices could not recognize the messages of interest given their proprietary format.)
A message processor may generate system fraud and roamer visibility data for use by a service provider in administering its wireless systems and detecting fraud. A portion of the message processor is in communication with at least one data capture device (as described herein), or other device, for capturing from a wireless system messages indicative of wireless system traffic, the messages corresponding to a number of classes. As an example, there may be a first class of xe2x80x9cchallengexe2x80x9d messages and a second class of xe2x80x9cresponsexe2x80x9d messages; these may be typical of any system that uses a query/response (or xe2x80x9cACKxe2x80x9d/xe2x80x9cNACKxe2x80x9d) certified delivery method. In wireless systems using IS-41 protocol, the first class of challenge messages would be an xe2x80x9cinvokexe2x80x9d message; the second class of response messages would be a return result messages.
At least one input port on the message processor may receive messages pertaining to wireless traffic from the data capture device or, if the message processor is centrally located, a plurality of data capture devices. The message processor may be coupled to at least one memory location. (The phrase xe2x80x9cmemory locationxe2x80x9d means a memory or data storage device of any sort, or a portion of such a device.) The message processor is programmed to: receive messages indicative of wireless traffic from a data capture device and store in the memory location received messages that belong to the first class. For each received message belonging to the second class, the message processor searches the memory location for a previously stored first class of message related to the received message. If any message located in the search is related to the received message of the second class, the message processor collates the received message with the located message, and provides the collated messages to an end-user or a processor.
A method associated with processing captured messages includes: receiving messages indicative of wireless traffic from the data capture device; storing the received messages belonging to a first class of message (e.g., IS-41 invoke messages) in the memory location; for each received message belonging to a second class (e.g., IS-41 return result messages), searching the memory location for a previously stored message of the first class related to the received message and, if any message located in the search of the memory location is related to the received message of the second class, collating the received message with the located message. Finally, the collated messages are provided to an end-user. Optionally, collated messages may be xe2x80x9cfilteredxe2x80x9d to eliminate those messages already being provided by a third party fraud or customer support system.
Generally, the message processor may be centrally located and in communication with various data capture devices via a LAN, WAN or equivalent communication path. Central location allows for easier changes to the functionality implemented by the message processor. Nevertheless, the message processor may also be deployed with and connected directly to each data capture device. This would free up valuable system bandwidth since raw, unprocessed messages will not be sent, as is the case with a centrally located message processor.
A system for capturing desired messages from a wireless system that uses a preselected signaling system and preselected protocol thus includes data capture devices that (i) monitor wireless system message traffic through various network elements or across at least one network telecommunications link and (ii) select from the monitored messages those corresponding to a preselected set of message types. The system also includes a message processor coupled by a transmission path or directly to the data capture device(s) and programmed to collate selected messages with one another to produce records associated with the wireless telecommunications traffic, as well as means for providing such records to an end-user.
Indeed, if desired, the present invention could be used not only to capture messages of interest but also to monitor for messages of interest. Tallies of messages of interest could then be processed to create various statistics relevant to network traffic and extremely helpful to network engineering or customer support and marketing.
Accordingly, the present invention provides visibility data at a low cost as well as data to maintain or improve the effectiveness of existing fraud detection systems. Adopting the present invention avoids interrupting fraud investigation if the wireless system replaces an X.25 or any other existing network, including a SS7 network operated by an outside network provider, with its own SS7 or other network. Using the present invention, fraud control systems can be deployed in other markets without relying on third-party network operators and without losing roamer visibility when a carrier utilizes a selected protocol, such as SS7, to transport validation transactions. Presently deployed wireless systems will enjoy enhanced productivity benefits flowing from the provision of more detailed, yet real time, customer support, network traffic engineering or other administrative information. By implementing the carefully designed on-line support system, wireless providers will nevertheless receive just the right amount of data of interest, thus optimizing use of valuable system bandwidth.
According to another embodiment of the invention, a system includes a catcher for receiving data from data capture devices. A parser reads the daily files and interprets the messages into tables and fields. If the received message is a registration message or a reject message, then these messages are preferably written into a registration daily file and a reject daily file, respectively. The messages are preferably paired together so that all invoke messages are stored with the corresponding response message.
In the preferred embodiment, the system and method according to the method preferably maintain a separate table for each message type and a master daily file containing general information on all messages received that day. The database is structured so that it holds a week""s worth of data, with the last day""s data being deleted with each new day. The database also preferably contains a table holding the most current registration information on each MIN. By storing message data into a plurality of tables, responses to queries can be generated more quickly. For instance, rather than reading all of the data in a daily file to determine the location of a particular MIN, the system and method can perform a quick look-up in the MIN table, which contains a significantly less amount of data than the daily files. The system and method furthermore conserve space on the database by coding entries in the tables and fields. For instance, rather than storing xe2x80x9cregistration notificationxe2x80x9d when this type of message is received, the system and method instead store a specific number for that message, such as xe2x80x9c38.xe2x80x9d
The system and method support a number of different types of queries. One such query is a MIN/ESN query. With this query, the roaming activity of a specific customer can be ascertained. This search may be performed on a single day or over a range of days. A second type of query that may be performed with the invention is an active roamer query. An active roamer query shows a list of roamers that are active in a serving market. This query may be limited to a certain SID, switch, home SID, or NPA-NXX. A third query supported with the invention is a switch-to-switch query. The switch-to-switch query provides information on all ANSI-41 messaging on one switch or between two switches. The search may be performed on a single day or a range of dates. A fourth query performed with the invention is a transaction statistics query. The transaction statistics query provides information on registration messages between two cellular service providers. With this query, information may be obtained on all subscribers roaming in a foreign market or information may be obtained on everyone served by a home network. This query can be limited to a home region, to specific dates, to a specific roaming partner, and to a particular company, SID, switch, NPA-NXX, or MIN.
From the results of any query, a user can obtain record details on any message. If a user double-clicks on a message in the results section, the information on that message is pulled from the message table and the information is displayed in a tabular format. Each tab of information contains data on a group of parameters. If no data exists for all parameters within a group, then that tab preferably is not displayed to the user.
The system and method provide extremely useful data to a service provider. For customer support, the service provider can more quickly determine the source of a customer""s problem. The service provider need not place any type of xe2x80x9csnifferxe2x80x9d on a switch but instead can quickly recall the messaging that occurred at the time of the customer""s problem. Customer support, for instance, can determine whether the customer is able to register, whether the customer is authorized for a particular service. The engineering and technical support of a service provider can determine the cause of a past problem and, by monitoring the messaging within the network, can even prevent future problems from occurring.
It is accordingly an object of the present invention to provide a data capture device for monitoring and capturing a variety of information on telecommunications traffic within a wireless system.
It is an object of the present invention to provide a plurality of data capture devices, some of which capture data from a telecommunications link, others of which are coupled to particular network elements from which data of interest is captured.
It is a further object of the present invention to provide captured data to an administrative facility, such as a central message processor, where the results are collated or otherwise processed to yield roamer visibility, fraud, or other data useful in the administration of a wireless system.
It is an additional object of the present invention to provide a message processor for (1) receiving messages captured by data capture devices coupled to telecommunications links or network elements in a wireless system and (2) processing the received messages to yield paired IS-41 or other messages that provide roamer visibility and data useful in the detection of fraud.
It is another object of the present invention to provide a central message processor including a database containing roamer visibility data available for query by one or more on-line customer support systems.
It is a further object of the present invention to provide methods and apparatus for providing a central message processor for processing captured messages as well as fraud data received from outside or third party providers to generate a fraud data feed from which redundant fraud-related information has been removed.
It is still a further object of the present invention to provide methods and systems for enabling useful queries to be performed based on captured data.
It is yet another object of the present invention to provide methods and systems for allowing the capture of real-time roaming statistics.
It is another object of the present invention to provide methods and systems for allowing the capture of real-time data for use by engineering or technical support.
It is still another object of the present invention to provide methods and systems for enabling results of a query of a database to be returned in a relatively short period of time.
Other objects, features and advantages of the present invention will become apparent upon reading the remainder of this document.

Systems and methods for monitoring data signals on a communications network

BellSouth Intellectual Property Corporation