A recording system employing a magneto-resistive (MR) element senses a resistance value of the MR element and generates one or more MR resistance (MRR) signal values based on the sensed MR element resistance value. The MRR signal values might be, for example, current or voltage values proportional or inversely proportional to the MR element resistance value. The MRR signal values might be employed to control one or more of: i) a unity gain bandwidth of a bias loop for the MR element, ii) an MR read head preamplifier low corner frequency, and iii) a slew rate across the MR element.

1. Field of the Invention
The present invention relates to circuits for transferring data to and from a recording medium and, in particular, to circuits of a magneto-resistive read head.
2. Description of the Related Art
Conventional recording systems of the prior art encode data and write the encoded data to a recording medium, such as a magnetic hard drive or an optical recording disc. A read channel component is an integrated circuit (IC) of a computer hard disk (HD) drive that encodes, detects, and decodes data, enabling a read/write head to correctly i) write data to the disk drive and ii) read back the data. The encoded data is written to the disc (or other recording medium) by a read/write head. In a magnetic recording system, data is recorded by a head by varying the magnetic field over a bit position ("cell") on the surface of the recording disc. Data is read by sensing magnetic variations corresponding to the data as the head passes over the cell.
Two types of disc drive systems might be employed to write information to or read information from a disc. One type is an inductive write/inductive read system, and the other type is an inductive write/magneto-resistive (MR) read system. Inductive write/inductive read systems employ a single inductive element (coil) that is used to both write and read data. However, as track densities increase, mismatch between ideal coil settings for write and read operations due to resonance frequency changes decreases the data bandwidth. Consequently, for inductive write/MR read systems, an inductive element is selected and optimized for write operations, while an MR element is employed for read operations. The MR element is a resistive element that is biased, either by voltage or current, and variations in the magnetic field detected by the MR element result in variations in the resistance value of the MR element. Variations in resistance of the MR element produce signal variations that are subsequently amplified by a preamplifier and provided as the detected data. An MR read head generally comprises the MR element, while the MR reader generally comprises at least a portion of the preamplifier having MR bias and other control loop circuitry (also termed an MR reader).
The resistance of a particular MR element in a given manufacturer's disk drive can vary over a wide range. It is desirable to accommodate head-to-head MR element resistance variations of 4:1 and higher in a given preamplifier design used in conjunction with the MR element. The value of the MR resistance (RMR) affects the design of a disk drive preamplifier used to amplify signals from the MR element. Head-to-head variations in RMR affect i) the gain and bandwidth of an MR element bias loop used to provide current/voltage bias to the MR element, ii) the setting of a low corner frequency of the MR reader, and iii) read-to-write and write-to-read transition times. Write-to-read transition time and read-to-write transition time are measures of the preamplifier's ability to quickly switch between operating modes.
In write mode, reduced or no bias voltage is applied to the MR element, because edge rates of the writer output are very fast. These edge rates might be fast enough to travel down the writer traces of the flex interconnect from the writer output of the preamplifier to the inductive write head, coupling across the interconnect to the reader traces on the flex interconnect which connect the MR element to the reader input of the preamplifier. Overbiasing the MR element can cause damage to the read head and reduce the read head's life span. So, reducing or removing the bias voltage placed across the MR element and pulling the read head to ground protects the MR element during write mode. When the preamplifier is in write mode, the MR bias loop is in slow mode for two reasons. First, in slow mode, the bandwidth of the loop is low so that any coupling due to the fast edges of the writer signal into the MR bias loop is ignored, and second, operating the MR bias loop in slow mode reduces power consumption. The difference between fast and slow modes is the MR bias feedback loop unity gain frequency. The unity gain frequency determines the rate that the MR bias can change.
When the preamplifier switches from write mode to read mode during the write-to-read transition, a bias voltage is applied relatively quickly to the MR element so that data may be read from the disk without wasting time or disk space. The preamplifier switches into fast mode so that the desired voltage applied to the MR element can be quickly reached. The MR bias loop then switches back into slow mode. In slow mode, the unity gain frequency of the MR bias loop is set below that of the lowest frequency content of the data to be read so that MR bias loop operation does not corrupt the data being read from the disk.
In read mode, the MR element has some bias voltage (or current) applied to it, and data is read from the disk. The MR bias loop operates in slow mode so as not to corrupt the data being read from the disk. As the preamplifier switches from read mode to write mode during the read-to-write transition, the MR bias loop switches into fast mode so that the bias voltage may be either reduced or removed altogether when in write mode. After the desired bias voltage level for write mode is reached, the MR bias loop switches back into slow mode.
Variations in MR resistance change the gain of the MR bias loop, thus affecting the MR bias loop's performance and stability. FIG. 1 shows a block diagram of prior art MR bias loop 100 that biases the MR element RMR in an MR reader. The voltage VMR across RMR (VMR is the voltage between nodes Vmr+ and Vmr−) is sensed and compared to a programmable offset voltage inside of gain stage 110. Gain stage 110 amplifies the difference between VMR and the programmable offset voltage by amplification factor A to provide output voltage VERR. The resulting output voltage VERR of gain stage 110 is amplified by transconductance stage 111 (with transconductance Gm, i.e., the slope of the transconductance stage's operating transfer characteristic).
The output signal of transconductance stage 111 is integrated via capacitor CINT, with the voltage across CINT employed to bias RMR through bias resistors RB1 and RB2 (RB1 substantially equals RB2 equaling RB) via isolating (unity-gain) amplifiers 102 and 103. MR bias loop 100 operates to drive VERR to zero volts (differential). When VERR is zero volts (differential), the bias voltage applied to the MR element RMR is equal to the programmable offset voltage.
The DC loop gain Aloop(DC) of MR bias loop 100 is given in equation (1):
                                          A                          loop                                            (                DC                )                                              =                                    AGmR              0                                                  (                                                R                  MR                                                                      R                    MR                                    +                                      2                                                              R                      B                                                                                )                                      ,                            (        1        )            where A is a constant and R0 is the output impedance of transconductance stage 111. The unity gain bandwidth (UGB) of MR bias loop 100 is given in equation (2):
                    UGB        =                                                            AGmR                0                                                          (                                                      R                    MR                                                                              R                      MR                                        +                                          2                                                                    R                        B                                                                                )                                                                (                              1                                  2                                                                                π                                                                                R                    0                                                                          C                    INT                                                              )                                =                                    (                                                AGmR                  MR                                                  2                                                                                π                                                                                C                      INT                                                                                (                                                                        R                          MR                                                +                                                  2                                                                                R                            B                                                                                )                                                                                )                        .                                              (        2        )            As shown in equation (1), a higher value of RMR yields a larger loop gain Aloop(DC), which may lead to loop instability. As shown in equation (2), a higher value of RMR also causes an increase in UGB.
The setting of a low corner frequency fLC of the MR reader also varies with variations in the MR resistance RMR. A second loop ("low corner frequency (LCF) loop") controls fLC of the first gain stage of the MR reader. For inductive write/MR read systems, a cross-coupled current sense (CCCS) reader is a preamplifier circuit that is employed with the MR element to read data from a recording medium. FIG. 2 shows CCCS reader 200 employed as the first gain stage of an MR reader. CCCS reader 200 is configured such that the changing magnetic field of the cell causes current variations in the MR element (RMR) as the element moves over the cell. CCCS reader 200 amplifies the current variations through RMR caused by varying differential input voltage VIN(=Vmr) across RMR, and translates them into an output signal VOUT representing sensed data. CCCS reader 200 includes a driver section for the voltage across RMR including transistors M1 and M2, load resistors RL1 and RL2 (RL1 equals RL2 equals RL), and current sources IA1 and IA2 that are configured as a differential amplifier through transconductance stage 201. CCCS reader 200 employs AC coupling of the driver section to transconductance stage 201 (through transistors Q1 and Q2, current sources IA3 and IA4, and coupling capacitors CCC1 and CCC2 (CCC1 equals CCC2 equals CCC).
The low corner frequency fLC of CCCS reader 200 is set to pass the lowest frequency content of the data being read from the disk while rejecting frequency content beneath that of the data. The unity gain bandwidth of the MR bias loop is maintained beneath that of fLC of CCCS reader 200. Otherwise, operation of the MR bias loop interacts with operation of the LCF loop, causing peaking in the frequency response of CCCS reader 200 and possible circuit instability. Furthermore, if the UGB of the MR bias loop extends to the frequency of data being read from the disk, then the MR bias loop corrupts the read data while attempting to maintain a constant bias across the MR read head.
However, it is desirable to maintain as high a gain as is possible in the MR bias loop so as to maximize accuracy of the MR bias loop. Thus, system designs that allow for a large variation in MR resistance make a trade-off between i) MR bias loop accuracy for low values of RMR and ii) UGB for high values of RMR.
The low corner frequency fLC of the MR reader is set by the gain of CCCS reader 200, the transconductance during slow mode (denoted by GmReader) of the CCCS reader 200, and the capacitance of the cross-coupling capacitors in the first gain stage of CCCS reader 200. The low corner frequency fLC is proportional to the approximation given in equation (3):
                                          f            LC                    ∝                                    AGm              Reader                                      C              CC                                ≈                                    2                                            R                L                                                          Gm                Reader                                                                    R                MR                                                          C                CC                                                    ,                            (        3        )
As shown in equation (3), fLC of CCCS reader 200 decreases as the value of RMR increases, which is the opposite of the effect of increasing RMR on the UGB of the MR bias loop. The risk of overlapping between i) the loop bandwidths of the MR bias loop and ii) the LCF loop setting the fLC, thus interfering with one another, due to variations in RMR increases substantially for larger variation range of RMR.
Read head voltage slew rate also varies with variations in RMR. The read head voltage slew rate is a measure of the preamplifier's (MR reader's) ability to rapidly change the bias voltage across the read head when switching between write and read operations. MR readers are increasingly sensitive to overbias conditions. Placing too large a voltage across the MR element significantly reduces the life expectancy of the head, and so avoiding voltage overshoot while ramping up the voltage across the MR element is desirable. While writing data to the disk, the MR bias circuit that provides the bias to the MR element may be turned off and both ends of the read head pulled to ground to minimize damaging effects from write head signals coupling onto the MR element. However, the MR reader should switch quickly from write mode into read mode to avoid wasting valuable disk space.
Referring to FIG. 1, there is a constant slew rate across integration capacitor CINT. The slew rate S is set by the maximum output current IGmMAX of transconductance stage 111 and the value of CANT and is as given by equation (4):
                    S        =                                            I              GmMAX                                      C              INT                                .                                    (        4        )
However, the slew rate SHEAD seen at the MR read head (across the MR element) varies proportionally to the value of RMR. The slew rate SHEAD at the MR element is given in equation (5):
                              S          HEAD                =                                            I              GmMAX                                      C              INT                                                      (                                          R                MR                                                              R                  MR                                +                                  2                                                        R                    B                                                                        )                                              (        5        )
With a range of values for RMR between 15Ω and 70Ω, and a typical value for RB of approximately 300Ω, the variation in slew rate at the MR read head may vary by approximately 4:1.
To minimize preamplifier switching time from write mode to read mode (the write-to-read recovery time), the maximum output current IGmMAX of transconductance stage 111 in MR bias loop 100 of FIG. 1 can be increased during this transition time. Increasing IGmMAx increases the slew rate seen at the MR reader, as given by equation (5). The value of Gm of transconductance stage 111 in MR bias loop 100 can be increased to a higher value during this transition from write mode into read mode. The increased value of Gm increases the UGB of the MR bias loop to maintain stability with the increased slew rate, which might be accomplished by i) increasing a tail current in a transconductance stage (Gm-stage) undegenerated differential pair, or ii) operating two Gm-stages in parallel. For the second method, a low-gain Gm-stage and a high-gain Gm-stage are used. The high-gain Gm stage is active only during the write mode to read mode transition.
With a faster slew rate seen at the MR read head, fLC of the first gain stage (e.g., CCCS reader 200) is also increased so that the LCF loop can track the rapid change in MR bias voltage without i) interfering with the MR bias loop, ii) causing overshoot in the MR bias voltage, or iii) instability. Increasing fLC of the first gain stage might be accomplished in a manner similar to that described for minimizing the preamplifier switching time by increasing the UGB of MR bias loop 100. The slew rate across the cross-coupling capacitors, CCC1 and CCC2, and the gain of the transconductance stage, GmREADER, are set to relatively high values during this write-to-read transition time, while still maintaining loop stability. This slew rate across the cross-coupling capacitors and the gain of the transconductance stage during this write-to-read transition time determine the maximum slew rate allowed at the MR read head. The maximum slew rate seen at the head occurs when RMR is at its maximum value, but to slew from zero volts across the read head to its final value (given the previously described range of values for RMR) might take up to four times longer when RMR is at its minimum value.

Magneto-resistive head resistance sensor


A heat-resistant alloy suitable as a material for reactor tubes such as cracking tubes for producing ethylene in the petrochemical industry consisting essentially of, in % by weight, 0.1 to 0.5% of C, over 0% to not more than 4% of Si, over 0% to not more than 3% of Mn, over 40% to not more than 50% of Cr, over 0% to not more than 10% of Fe, 0.01 to 0.6% of Ti, 0.01 to 0.2% of Zr, at least one element selected from the group consisting of 0.5 to 5% of W, 0.3 to 2% of Nb and 0.5 to 3% of Mo, and the balance substantially Ni. The alloy is excellent in oxidation resistance, high-temperature creep rupture strength, carburization resistance and ductility after aging.

The tubes for thermally cracking hydrocarbons, for example, those for producing ethylene by thermally cracking naphtha or the like under the conditions of high temperature and high pressure (about 800.degree. to about 1100.degree. C. in temperature and up to about 5 kg/cm.sup.2 in pressure) while passing the material through the tube must have high resistance to oxidation and mechanical strength (especially creep rupture strength) at high temperatures. The cracking tube must be outstanding also in resistance to carburization because solid carbon separates out from the reaction system during operation and causes carburization by adhering to the inner surface of the tube wall and diffusing through the tube wall to deteriorate the tube material and thereby embrittle the tube.
Such reactor tubes are usually prepared from HP material (0.4C-1.75Si-25Cr-35Ni-Fe) according to ASTM standard, improved HP material (0.4C-1.75Si-25Cr-35Ni-Mo, Nb, W-Fe), etc.
From the viewpoint of improved operation efficiency and productivity, it has recently been required to conduct the thermal cracking reaction of hydrocarbons at about 1150.degree. C. or higher temperatures.
However, the conventional tube materials, although usable at temperatures of about 1100.degree. C. to about 1150.degree. C., encounter difficulty in ensuring the safety of operation at higher temperatures, rapidly deteriorating especially owing to insufficient carburization resistance to become shortened in service life.
Cracking tubes locally degraded as by carburization are repaired usually by removing the degraded portion and welding for replacement. However, if the tube has been markedly impaired in ductility after aging, the tube is liable to weld cracking due to the embrittlement of the tube material when repaired by welding. For this reason, the reactor tube material needs to have high ductility after aging.
Thus, the reactor tube material is not suitable if low in one of the foregoing characteristics, i.e., oxidation resistance, creep rupture strength at high temperatures, carburization resistance and ductility after aging.
In view of the above problem, the present invention provides a heat-resistance alloy which is outstanding in oxidation resistance, creep rupture strength at high temperatures, carburization resistance and ductility after aging for use as a tube material which is least likely to embrittle so as to ensure durability and safety of operation.


A thin, deformable member may be fixed at one end, while another portion of the member rests on a hydrogel substance whose thickness changes depending on a characteristic of a liquid that permeates the hydrogel. When the hydrogel changes thickness and causes part of the member to tilt, a reflective surface on the member may reflect light in a different direction. Appropriate sensors may detect the change in the direction of the reflected light, allowing determination of the change in thickness, which in turn permits determination of the relevant characteristic of the liquid.

In various areas of medical, chemical, and/or biological technology, it is often desirable to measure the properties of an aqueous solution. For example, it might be desirable to measure pH, temperature, glucose concentration, etc, which typically requires a customized procedure for each type of measurement. Older techniques frequently involve mixing another chemical in the solution and looking for a detectable change, such as a change in color, a change in electrical conductivity, the production of salts, etc.
More recent techniques may use a hydrogel substance that changes its thickness based on the pertinent characteristics of the solution as that solution permeates the hydrogel. If the hydrogel substance is a few millimeters in size, it may take a long time (e.g., hours) for the solution to permeate the hydrogel substance to produce the desired change in thickness. Reducing the size to a few micrometers may reduce the time to permeate and the resulting time to get an accurate reading to a few seconds. However, directly measuring a change in thickness of only a few micrometers may be difficult and expensive.

Hydrogel-actuated micromirrors for optical sensing


A master provides a byte length of a frame in a certain position of the frame. The master also provides an error detection code in the final byte. After sending the final byte, the master monitors whether or not a negative acknowledgement is received. If a negative acknowledgment is received, the master transmits a dummy byte and then sends a stop condition. A slave counts the number of received bytes and compares the number of received bytes with the byte length of the frame. If the number of received bytes is larger than the byte length of the frame, the slave recognizes negative acknowledgement.

1. Field of the Invention
The present invention relates to data communication methods used in serial data transfer systems, and more particularly, to a data communication method used in a serial data transfer system in which a master (sending unit) sends serial data to a slave (receiving unit) via, for example, an inter-integrated circuit (I2C) bus.
2. Description of the Related Art
As shown in FIG. 5, in a serial data transfer system for sending serial data via an I2C bus, at least two units, a unit (master) 1, which is a sending unit, and a unit (slave) 2, which is a receiving unit, are connected to each other using a serial data line (SDA line) 3 for transferring data and a serial clock line (SCL line) 4 for transferring clock signals. In the master 1 and the slave 2, SD represents a data sending terminal, RD represents a data receiving terminal, SC represents a clock sending terminal, and RC represents a clock receiving terminal.
As shown in FIG. 6, the master 1 transfers a start condition S from the data sending terminal SD and the clock sending terminal SC via the SDA line 3 and the SCL line 4 such that a data signal SDA and a clock signal SCL have a predetermined first phase relationship at the start of a frame, and also transfers a stop condition P such that the data signal SDA and the clock signal SCL have a predetermined second phase relationship at the end of the frame. The master 1 transfers n-byte data in synchronization with clocks between the start condition S and the stop condition P.
The slave 2 detects the start condition S from the data receiving terminal RD and the clock receiving terminal RC to start reception of a frame, and sends an acknowledgement A from the data sending terminal SD to the master 1 via the SDA line 3 every time one byte of data is received. The slave 2 identifies the end of the frame from the stop condition P.
In other words, the master 1 sends the start condition S to the slave 2. Then, the master 1 sends a slave address as the first bit to the seventh bit, and sends a read/write control signal R/W as the eighth bit. After receiving an acknowledgement A sent from the slave 2 as the ninth bit, the master 1 transfers n bytes as transmission data, receives an acknowledgement A sent from the slave 2 every time one byte of data is transferred to the slave 2, and sends the stop condition P at the termination of data transfer.
FIG. 7 explains the levels (L: low level or H: high level) of signals output to the SDA line 3 and the SCL line 4 from each of the master 1 and the slave 2 when communication is performed via an I2C bus. When the master 1 performs transmission to the slave 2, the slave 2 outputs an "H" signal to the SDA line 3 and the SCL line 4, as shown in FIG. 7(b), and the master 1 outputs an "H" signal and "L" signal to the SDA line 3 and the SCL line 4 in accordance with data and a clock signal, as shown in FIG. 7(a). When one of the master 1 and the slave 2 outputs an "H" signal to a line, if the other of the master 1 and the slave 2 outputs an "L" signal, the line represents "L".
In other words, when the master 1 sends the start condition S, the SCL line 4 is "H" and the SDA line 3 is changed from "H" to "L". When the master 1 sends the stop condition P, the SCL line 4 is "H" and the SDA line 3 is changed from "L" to "H". Also, in order to receive an acknowledgement A, the master 1 outputs an "H" signal to the SDA line 3 as the ninth bit after sending a byte. In contrast, the slave 2 receives data sent from the master 1 to the SDA line 3 while outputting an "H" signal to the SDA line 3 and the SCL line 4, and outputs an "L" signal ("H" for NACK) to the SDA line 3 as the ninth bit after receiving the byte in order to send an acknowledgement A, as shown in FIG. 7(c). Also, after detecting the falling edge of the ninth clock bit, the slave 2 changes the SDA line 3 from "L" to "H". The slave 2 detects the stop condition P to complete reception of the frame.
Noise interference or a waveform distortion may cause a clock difference between a transmitter and a receiver. With such a difference between the transmitter and the receiver, the receiver may terminate reception processing normally even if the transmitter detects a communication error in the final byte of a communication frame.
FIG. 8 explains a state in which the master 1 recognizes abnormal termination but the slave 2 recognizes normal termination. When the sixth bit clock is regarded as two clocks due to interference of a noise component N, which is shown in FIG. 8 (c), in the SCL line 4, the slave 2 regards the normal seventh bit as the eighth bit. Then, if a frame is received successfully, the slave 2 outputs ACK (="L") to the SDA line 3. Thus, the slave 2 regards the normal eighth bit as the ninth bit. After detecting the falling edge of the ninth bit, the slave 2 outputs an "H" signal to the SDA line 3.
In contrast, the master 1 receives an "H" signal on the SDA line 3 as NACK at the normal ninth bit (A bit). Then, the master 1 sends the stop condition P. Since the slave 2 outputs an "H" signal to the SDA line 3 and the SCL line 4, the stop condition P represented by a dotted line 15 appears on the SDA line 3 and the SCL line 4. The slave 2 detects the stop condition P to normally terminate processing.
As described above, in the case where a receiver normally terminates reception processing although a transmitter recognizes abnormal termination causes the following problems:                1) inconsistency of operation as a system;        2) possibility of unintentional operation; and        3) possibility of malfunction.
For example, retransmission performed by a transmitter that terminates abnormally causes a problem described below. When an instruction for switching on a power supply is abnormally terminated, the transmitter resends the instruction to the receiver. Thus, the instruction for switching on the power supply is reported twice to the receiver. As a result of this, the receiver switches on the power supply in accordance with the first instruction, and then switches off the power supply in accordance with the second instruction. Thus, the receiver performs an operation that is not desired by the transmitter. Consequently, it is necessary for the receiver to recognize abnormal termination when the transmitter recognizes abnormal termination.
One approach for avoiding malfunction in I2C bus communication is disclosed, for example, in Japanese Unexamined Patent Application Publication No. 9-265436. In this approach, in order to avoid a malfunction caused when a master (microcomputer) reads or writes data from or to a slave (nonvolatile memory) when an SDA line is "L", the master performs an access operation after confirming that the slave releases a bus.
Also, a data transfer method for avoiding contention on a bus connecting a master to a slave is disclosed, for example, in Japanese Unexamined Patent Application Publication No. 2001-290764. In this approach, when the master performs transmission, the slave monitors whether or not data having a predetermined number of bytes is received from the master. When the data having the predetermined number of bytes is received, the data line is released, and the slave sends data to the master.
However, the known approaches described above do not solve the problems where the transmitter recognizes abnormal termination but the receiver recognizes normal termination.

Data communication system, data communication method, and communication unit


An entity modeling system integrated with a low-code application development platform may have a web/mobile-based user interface that can run in a browser environment on user devices ranging from desktop computers to smart phones. Users such as a subject matter expert may access an entity model designer tool of the system to model an entity. Responsive to user interaction with an entity composition function, the system may access a data store over a network and generate a view including a collection of entity building block(s) retrieved from the data store. Responsive to the user selecting a first entity building block from the collection to add to the entity, the system may automatically extend the entity to include settings of the first entity building block. The settings may include at least one of a property, permission, action, behavior, or resource to the entity.

In software engineering, an entity model, or entity-relationship model, refers to a particular type of data model that describes and defines a process in a problem domain. This process is modeled as components (entities) that are linked with each other by relationships that specify dependencies and requirements between them.
An entity model can be created by a data modeler using software tools. The entity model thus created can be translated into a physical database design and mapped to physical storage devices by a database administrator (DBA). For example, in the case of a relational database management system which stores data in tables, every row of each table represents one instance of an entity. Some data fields in the tables point to indexes in other tables. Such pointers represent the relationships.
As is known, a database management system is a complex software program that provides users with a systematic way to create, retrieve, update, and manage data. There are a number of problems with an existing approach to entity modeling in an application development environment that relies on data modelers (e.g., the IT staff) knowing how to interact with database management systems, essentially requiring them to have data administration and entity modeling expertise. However, the skills required for entity modeling are different from the skills required for data administration. As such, a data modeler may spend time working on what functionality to add to an entity as well as on figuring out how to correctly and appropriately add that functionality to an entity. What is more, traditional application development approaches require business requirements to be developed and then implemented by the IT staff. This process can take months and requires specialized IT personnel.
Furthermore, the existing approach to entity modeling involves using different software tools. Since the entities and their relationships are stored in a database, these software tools must provide a way to access them in the database. To do so, code for different user interfaces need to be written and implemented and data modelers need to learn how to use these software tools. Moreover, functions provided by one entity modeling tool may not be reusable or extensible by another entity modeling tool.
In view of the foregoing, there is a need for innovations and improvements to entity modeling in enterprise computing environments.

This patent is subject to a terminal disclaimer.

Compositional entity modeling systems and methods


A wireless communication system includes a repeater and a terminal device. The terminal device is connected to the repeater via a wireless communication channel. The terminal device includes a first section for converting a first electric signal into a first wireless signal, and transmitting the first wireless signal toward the repeater along the wireless communication channel. The terminal device includes a second section for receiving a second wireless signal from the repeater via the wireless communication channel, and converting the second wireless signal into a second electric signal. The terminal device includes a third section for deciding whether or not the first electric signal and the second electric signal are equal to each other to detect whether or not a signal collision occurs on the wireless communication channel.

1. Field of the Invention
This invention relates to a wireless communication system using light wave, radio wave, or the like.
2. Description of the Prior Art
In a wired LAN (local area network), terminal devices are connected to each other via wires. The terminal devices can communicate with each other via the wires.
It is known to combine a wired LAN and a wireless communication network. For example, a wired LAN is additionally provided with an access point device (a gateway device) which can execute both wired communication and wireless communication. The access point device is connected via wires to normal terminal devices in the wired LAN. The access point device can communicate with the normal terminal devices in the wired LAN via the wires. Also, the access point device can execute wireless communication with terminal devices in a wireless communication network. In this case, the wired LAN and the wireless communication network are connected via the access point device (the gateway device). In addition, the access point device is a member of the wired LAN as well as a member of the wireless communication network.
In a wireless communication network, if two terminal devices simultaneously transmit wireless signals toward another terminal device, the transmitted wireless signals collide with each other. In this case, both the transmission-side terminal devices fail to normally communicate with the reception-side terminal device.
There is a wireless communication network of a CSMA (carrier sense multiple access) type. In the CSMA wireless communication network, when a terminal device is required to transmit a wireless signal, the terminal device executes a process of sensing a carrier to check whether a communication channel is occupied or unoccupied. When the communication channel is unoccupied, the terminal device executes the transmission of the wireless signal. When the communication channel is occupied, the terminal device falls into a stand-by state to avoid a signal collision.
In a wired LAN, if two terminal devices simultaneously transmit signals toward another terminal device via a common bus wire, the transmitted signals collide with each other. In this case, both the transmission-side terminal devices fail to normally communicate with the reception-side terminal device.
There is a wired LAN of a CD (collision detection) type. In such a wired LAN, every terminal device monitors the level of a voltage at a common bus wire to check whether the common bus wire is occupied or unoccupied. The information of whether the common bus wire is occupied or unoccupied is used in avoiding a signal collision.
There is a wired LAN having a star connection between a hub device and terminal devices. The connection between the hub device and each terminal device includes a duplex line. Such a wired LAN intrinsically has a function of avoiding a signal collision.

Enhanced signal collision detection method in wireless communication system

NTT Data Communications Systems Corporation


An apparatus and method for elemental analysis of a formation fluid from a subsurface tool having a housing, a sampling probe for collecting a sample of the formation fluid external to the housing, and a microplasma device within the housing and in fluid communication with the sampling probe. The microplasma device includes an upstream gas system, a sampling valve in fluid communication with the sampling probe and the upstream gas system, an expansion chamber for volatizing the formation fluid sample obtained from the sampling valve, and a microplasma chamber in fluid communication with the expansion chamber for ionizing the volatilized fluid sample.

Hydrocarbon producing fields typically include a subterranean fluid that is comprised of a mixture of oil, gas and water, wherein the phase relationship between these components are controlled by the pressure, temperature and composition of the fluid. It is desirable to analyze and evaluate these fluids to determine fluid characteristics of commercial interest to the petroleum industry, such as the type and quality of the components within the reservoir. One way to accomplish this is by retrieving a sample of the subterranean formation fluid to the surface and analyzing the fluid to determine its composition.

Microplasma for downhole compositional analysis


An apparatus for synchronizing a terminal equipment such as a TV camera includes an external synchronizing signal generator which includes a switching circuit which generates two frequency signals and alternately transmits these signals to the terminal equipment which is provided with a decoder circuit decoding an alternating rate of the two signals outputted from the synchronizing signal generator, and an internal synchronizing signal generating circuit receiving a decoder circuit and generating a new synchronizing signal on the basis of the decoded signal.

1. Field of the Invention
This invention relates to an apparatus for synchronizing a terminal equipment, by using an external synchronizing signal, and more particularly, to a synchronizing apparatus suitable for a television camera having means for generating a horizontal synchronizing signal and a vertical synchronizing signal or composite synchronizing signal.
2. Description of the Prior Art
In a monitor television system used as one of information transmission systems, at least one television monitor is connected to a plurality of television cameras through an electronic switch and a plurality of transmission lines. The electronic switch provides selection of any one of the television cameras or sequential switching and displaying on the television monitor a picture image of one camera after another.
In such an information transmission system, it is necessary to mutually lock the internal synchronizing signals of a plurality of television cameras to an external synchronizing signal, in order to prevent the picture image on the monitor from being disturbed during and immediately after the switching operation from one television camera to another.
As one of the devices for synchronizing a plurality of television cameras, there is known an apparatus for transmitting a horizontal synchronizing signal and a vertical synchronizing signal used in a television system from an external synchronizing generator to the television cameras, and driving the television camera by the transmitted horizontal synchronizing signal, and the vertical synchronizing signal, or the composite synchronizing signal.
Another known apparatus for synchronizing a plurality of television cameras, is an apparatus for transmitting an external synchronizing signal from an external synchronizing generator to the television cameras and locking an internal synchronizing signal generator of the television camera by means of the transmitted external synchronizing signal. Such an apparatus is disclosed in U.S. Pat. No. 4,603,352, the contents of which are incorporated herein by reference.
In any of the known devices of the type under discussion, as the transmitted synchronizing signal itself is a train of pulses, which can be easily influenced by noise, the transmission of a synchronizing signal requires the use of a coaxial cable with its high shielding effect, which makes it difficult to transmit the synchronizing signal over long distances.

Apparatus for synchronizing terminal equipment


A wavelength conversion module according to the present invention includes an external resonator, a semiconductor laser module and a wavelength conversion device for converting a wavelength of light output from the semiconductor laser module into a shorter wavelength. This wavelength conversion device includes at least one of a nonlinear crystal for generating SFG (Sum-frequency Generation) light and a nonlinear crystal for generating SHG (Second Harmonic Generation) light. Each of the SFG generating element and the SHG generating element of the wavelength conversion device may have a periodically-poled ridge-waveguide structure or a periodically-poled proton-exchanged-waveguide structure.

Light output from a GaAs semiconductor laser has a wavelength which covers from around 1 μm to the 600 nm range, while a GaN semiconductor laser has been developed to output light with a wavelength of 405 nm mainly for use of next generation DVD light source. Well known as a laser of wavelength between them, that is, between about 400 nm and the 600 nm range are an Ar laser (488 nm/515 nm) and a combination of YAG/YLF and SHG (532 nm), for example.
The combination of YAG/YLF and SHG (532 nm) is developed for high power use (W level) and the YAG/YLF and SHG market is rapidly expanded in the fields of a marker of Si board or the like and trimming or repairing of TFT liquid crystal. Particularly, since a "marker" is now in increasing demand because of expanding demand for CSP (Chip Size Package) to be implemented in a mobile device, application of particularly YAG combined SHG laser module thereto is becoming active.
Further, in the trimming and repairing area, demands for repairing a display defect of TFT liquid crystal display are rapidly increased against the backdrop of increased production of TFT liquid crystal displays.
On the other hand, as a low power use, it is applied to measuring instrument, printing devices, DNA analyzers and the like.
FIG. 4 shows a conventional structure of an SHG blue (oscillation wavelength of 473 nm) or green (oscillation wavelength of 532 nm) laser module (for example, refer to "The Review of Laser Engineering" December 1998, pp 861 to 866).
A blue wavelength conversion SHG laser module 25 utilizes as a laser crystal a YAG crystal 21 and as a pumping light source a wide-stripe semiconductor laser device 5 of emission width 50 μm and maximum output 500 mW.
Semiconductor laser light output from the above-mentioned semiconductor laser device 5 is gathered inside the YAG crystal 21 via a lens 20 to initiate laser oscillation with the fundamental of wavelength 946 nm from the YAG crystal 21. Then, an SHG device (PPMGLN: Periodically poled MgO—LiNdO3 crystal) 22 converts the wavelength to output wavelength converted blue light of wavelength 473 nm, which then passes through an etalon 23 and a mirror 24 to be output.
However, the above-described conventional technique has a problem such that the YAG crystal 21 is heated when the fundamental is emitted by laser oscillation and the wavelength of light emitted from the YAG crystal 21 is shifted from the set wavelength. When the wavelength is shifted, an output from the SHG laser module becomes unstable.
In addition, as the biotechniques including fluorescence microscope and fluorescence analyses have been developed, there are demands for an inexpensive visible light (400 nm to 532 nm) laser for fluorescence excitation. However, its suitable laser module has not been realized yet.


An air conditioner may be provided. The air conditioner may include a housing disposed on a base, the housing may house an evaporator unit, a condenser unit, and a compressor unit. A first air inlet and a first air outlet may be located on a first end of the housing. The first air inlet, the first air outlet and the evaporator may be connected to each other to form an internal air circulation system. A second air inlet and a second air outlet may be located on a second end of the housing. The second air inlet, the second air outlet and the condenser unit may be connected to each other to form an external air circulation system. Airways of the internal air circulation system and the external air circulation system may be independent from each other.

A traditional air conditioner is a big bulk, and only be powered by the utility power. It thus is inconvenient for the use in outdoor environment, for example, a construction site, camping site. To meet people's desire to use an air conditioner to adjust surrounding ambient temperature in an outdoor activity, there exist portable air conditioners on the market. The portable air conditioners are easily moved and carried at any time. The common portable air conditioners may include a casing, a base, an evaporator (or a cooler), a condenser (or a heat sink), a compressor, an air inlet, an air outlet, and so on. The evaporator, the condenser and the compressor may be connected through a circulation pipe. However, the common portable air conditioners on the market still have many shortcomings to be improved. For example, an air outlet of the air conditioners is disposed at the front end of the casing, an exhaust outlet of the air conditioners is disposed at the rear end of the casing, and the air inlet is disposed at a side of the casing. In such a design, air may enter the casing from the air inlets on two sides, then get cooled in the evaporator and finally, the cooled air may be sent out from the air outlet. In some cases, this design easily causes some issues. For example, the air enters from a side and then leaks from the side. As another example, the cooled air is directly sucked into the air inlet and exchange heat with the condenser, then the cooled air is discharged, which may cause irregularity of the air circulation. As a further example, if an internal air circulation and an external air circulation are not independent, it may reduce the efficiency of an air heat exchange and utilization rate, and may also reduce the cooling efficiency of the air conditioner. In some cases, when using the common air conditioner, at least one part of the air inlet may need to be placed indoor, and at least one part of the air outlet is placed outdoor, so it is not convenient to install the air conditioner. Moreover, for a portable air conditioner, a drainage system for discharging condensed water is needed, which may require a large space for installing the air conditioner, and make internal structures of the air conditioner more complicated, resulting in the inconvenience to move and carry.


A precision soft-touch gripping mechanism has a mounting plate attached to a robot arm. The plate supports a stepper motor. The output shaft of the stepper motor is connected through a spring to an elongated finger that slides in a central longitudinal slot of the plate and supports a first wafer gripping post, while on the end opposite to the first wafer gripping post the mounting plate pivotally supports two L-shaped fingers with a second and third wafer gripping posts on their respective ends. The mounting plate in combination with the first sliding finger and two pivotal fingers forms the end effector of the robot arm which is thin enough for insertion into a wafer-holding slot of a wafer cassette. The end effector is equipped with a mapping sensor for detecting the presence or absence of the preceding wafer, wafer position sensors for determining positions of the wafer with respect to the end effector, and force sensors for controlling the wafer gripping force. Several embodiments relate to different arrangements of gripping rollers and mechanisms for control of the gripping force and speed of gripping required for gripping the wafer with a soft and reliable touch.

One of the major methods used at the present time in the semiconductor industry for grasping, holding, moving, and positioning of semiconductor wafers is the use of a mechanical hand of a robot equipped with a vacuum chuck.
From the beginnings of the semiconductor industry to the late 1980s, wafers were handled manually and later by rubber-band conveyors and cassette elevators. The first standards for wafer of 2″, 4″, 6″ diameters and appropriate cassette dimensions allowed to develop simple wafer handling mechanisms and standardize their designs. The early forms of automated handling contributed to improved yields by reducing wafer breakage and particle contamination. A variety of equipment layouts were used, but the general conception remained the same. In other words, the automation systems of that time relied mostly on stepper-motor-driven conveyor belts and cassette elevators to eliminate manual handling.
A central track would shuttle wafers between elevator stations that serviced cassettes and "tee" stations that serviced the process stations. This to some extent helped to reduce breakage, but did not solve the contamination problem. Furthermore, most equipment had manual loading as the standard, with the conveyor and elevators added. These systems were reliable and cheap and served as a good prerogative to automation of wafer handling by the times when 200-mm wafers came into use.
Further progress of the industry accompanied by an increase in the diameter of wafer with 200-mm diameter as a standard for substrates led to drastic changes in principles wafer handling occurred. Driven by ever-decreasing linewidths, tighter cleanliness and throughput requirements, and improvements in robotic technology, the rubber-band conveyor/cassette elevator solution was surpassed by true robotic wafer handling.
The new robotics consisted of polar-coordinate robot arms moving wafers with so-called "vacuum end effectors. In robotic, the end effector is a device or tool connected to the end of a robot arm. For handling semiconductor wafers, an end effector may be made in the form of grippers of the types described, e.g., in U.S. Pat. Nos. 5,108,140, 6,116,848, and 6,256,555. More detailed description of these end effectors or grippers will be considered later.
These robots were an improvement over the earlier technology. Since the robot's movements were controlled by microprocessor-based servo controllers and servomotors, it became possible to greatly improve the throughput, reliability, and error handling of the wafer handling systems. For example, a typical rubber-band conveyor and cassette elevator system could handle only tens of wafers per hour, while a three-axis robot could move hundreds. Reliability for robots was increased at least up to 80,000 hours mean time between failures (MTBF) compared to a few thousand hours for the conveyor systems. In the case of emergency situation the operator must immediately locate a wafer. This was not always possible with a belt-drive conveyor that could not always determine a current position of the wafer, whereas a robot system, which was characterized by a few possible wafer locations, could significantly facilitate a solution of the problem and allowed automated error handling.
Introduction of microprocessor control allowed true unattended equipment operation. Operators could manually load cassettes, and the tool could automatically process full wafer lots. Standards also were improved and introduced into use (see, e.g., SEMI standards). However, these standards helped reduce, but did not eliminate, the confusion involved in the selection and application of robotic wafer handling. For example, there are SEMI standards for cassettes, yet many nonstandard cassettes are used. Another compromise is the need to design semiconductormanufacturing equipment suitable for accepting a large variety of wafer sizes. This adds unnecessary complexity to equipment design.
Furthermore, many equipment manufacturers built their own robots. Each model had to be adaptable to many different wafer sizes and a variety of cassettes.
Recent transfer to 300-mm wafers, evolved new problems associated with much higher cost of a single wafer (up to several thousand dollars as compared with several hundred dollars for 200 mm wafers) and thus required higher accuracy and reliability of the wafer handling equipment. These problems becomes even more aggravated for handling double-sided polished wafers, where both sides of the wafer are used for the production of the chip. In other words, only edges of the wafers could be used for gripping, moving, and positioning of the wafers.
Furthermore, transition to 300 mm wafers made the use of low vacuum unsuitableforholding and handling the wafers. The main reason that in order to protect the wafer from contamination through the mechanical contact with holding parts of the robot arm, both sides (front or back) of the wafer becomes untouchable for handling. Another reason is that vacuum holders are not reliable for handling wafers of heavy weight. Thus, the conventional vacuum end effectors appeared to be unsuitable for handling expensive, heavy, and hard-to-grip wafers of 300 mm diameter.
According to Semi Standards, the allowance for the gripping area of the 300 mm wafer should not exceed 3 mm from the edge of the wafer and preferably to be down to 1.5 mm or even less. To reliably hold the wafer and to protect it from breaking during all handling transportation procedures, it is necessary to use a limited holding force of at least at 3 points circumferentially spaced along the edge of the wafer.
Since the position of each cassette and each wafer within the cassette is unique, the location of each wafer within the three planes of the orthogonal coordinate system relative to the reference plane of robot arm should be measured and used for precise positioning of the robot arm that carries the gripper. Using mechanical measurements or preliminary mapping procedures of location of the wafer in a cassette for precise positioning of the gripper relatively to the grasping points is a time consuming procedure that is difficult to perform in real conditions of the variety of wafer stages at wafer handling robotic lines.
U.S. Pat. No. 5,570,920 issued on Nov. 5, 1996 to J. Crisman et al. describes a robot arm with a multi-fingered hand effector where the fingers are driven from a DC motor via a system of pulleys with control of a grasping force by means of strain gauges attached to the inner surfaces of the fingers. However, such a robot arm is three-dimensional and is not applicable for handling thin flat objects, such as semiconductor wafers, located in a deep narrow slots of a multistack cassette of the type used for storing the wafers.
U.S. Pat. No. 6,167,322 issued on Dec. 26, 2000 to O. Hollbrooks, which describes Intelligent wafer handling system, is typical of the state of the art in two aspects. Hollbrooks system removes wafer from the cassette using a gripper that can slip in between parallel stacked and spaced wafers that has one or more actuating rods and one or more rotating fingers which are rotated by 90 degrees. Translator solenoid acting through an arm applies lateral movement to the finger to grasp the wafer between the finger and the posts. Grasping action is accomplished by using the finger to pressure the wafer against the fixed rods. The level of the pressure is maintained through the control of the electrical current applied to the driving translator. Hollbrook claims that the system can locate the position of the wafer with high degree of accuracy by employing light beams and photo sensors. The intelligent wafer handling system consists of a wafer mapping sensor mounted on the wrist end of the hand. The optics of the sensor is comprised of optical transmitters such as lasers or IR diodes and optical receivers such as CCD's or photo transistors used to receive reflections from the edge of the wafer. To determine the position of the front edge of the wafer, Hollbrook recommended using laser distance measuring unit. A laser head located on a two-axis mount would sweep the column of wafers in the cassette. To avoid the misreading of the wafer position, the sensor should span the small focal point across the edge. Hoolbrook recommended to avoid bending or cracking a wafer by lifting the movable finger, controlled precisely by closely controlling current through the voice coil of actuator.
A disadvantage of the wafer handling system of Hollbrooks consists in that this apparatus does not provide control of gripping speed at different stages of the gripping cycle. Another disadvantage of the Hollbrooks system consists in that this system does not provide decrease in gripping pressure when the gripper approaches the edge of the wafer with acceleration.
U.S. Pat. No. 5,504,345 issued on Apr. 2, 1996 to H. Bartunek et al discloses a dual beam sensor and an edge detection system. Two light sources of solid state lasers are used to detect the edges of the wafers in a cassette. The solution proposed by Bartunek et al. to install the wafer mapping sensor on the wrist end hand or on one side of gripper does not solve the problem of detecting the wafer before gripping or during regular mapping process. The wafer placed on the robot arm in front of the sensor would cover the field of view of the sensor. It is impossible to see the wafer in the next slot of the cassette looking above the front side of the wafer if the position of the sensor is determined by the recommendation of Bartunek's patent. But even if the precise position of the front edge of the wafer is known, there is no guarantee that the position of the backside of the wafer is related to the same plane as the front edge. In the meantime any inclination and tilted position of the wafer in a cassette might lead to wafer breakage during the gripping process.
U.S. Pat. No. 6,256,555 issued to Paul Bacchi, Paul S. Filipski on Jul. 3, 2001 shows gripping end effectors for wafer of more then 6 inches in diameter that include proximal and distal rest pads having pad and backstop portions that support and grip the wafer within the annular exclusion zone. The end effector includes a fiber optic light transmitting sensor for the wafer periphery and bottom surface. A disadvantage of the device of U.S. Pat. No. 6,256,555 consists in that this device does not allow to divide the gripping process into several stages with different controllable speeds. In order to prevent jerks at the moment of contact of the gripper with the wafer edge, the last stage of movement of the gripping fingers should be carried out with a reduced speed. The decrease in speed, however, reduces productivity of the gripper's operation. This problem is solved neither by the device of U.S. Pat. No. 6,256,555 nor by any of the previously described devices.
U.S. Pat. No. 5,108,140 issued on April 1992 to S. Bartholet discloses a palm plate and grippers having tactile or other sensors on their upper surfaces to detect the position of the wafer and provide feedback to the control mechanism. A parallel vice-like grip is generated, but there are no means of detecting the real orientation of the wafer relative to the gripper. To control the gripping force directly at the gripping points of the wafer, it is necessary to measure two dimensional coordinates of the plane of the wafer, the relative coordinates, the front and backside edges, and adjust the gripping points to performed measurements and gripping procedures in real time. More problems related to a limited load that robot arm is able to carry and the amount of wires that can deliver the control and sensing signals to a robot controller.
Thus none of the existing robot-arm end effectors is suitable for grasping and moving semiconductor wafers with high precision and grasping force controlled so as to provide soft touch without loss in productivity of the gripping device.

Precision soft-touch gripping mechanism for flat objects


An improved surface seeded exposed particulate concrete and method of making the improved surface seeded exposed particulate concrete is disclosed. Small particulate is sprayed over the upper surface of the concrete. The particulate may be sprayed using a material sprayer. The particulate may be uniformly sprayed to distances exceeding twenty feet. The particulate is mixed into a cement paste derived from the concrete mixture using floats. A surface retarder is then applied to cover the concrete surface. Subsequently, any surface film is washed from the surface of the concrete and the concrete is cured. The result is a surface seeded particulate with an exposed surface that is flat and is suitable for high traffic areas. The resultant surface may resemble stone, granite or marble.

The present invention relates in general to exposed particulate concrete, and in particular to an improved method for surface-seeding the particulates into the upper surface of the concrete.
U.S. Pat. No. 4,748,788 entitled SURFACE SEEDED EXPOSED AGGREGATE CONCRETE AND METHOD OF PRODUCING SAME, hereby incorporated by reference in its entirety, discloses a surface seeded exposed aggregate concrete characterized by the use of small, rounded aggregate, such as sand, being broadcast over the upper surface of concrete. The method disclosed results in a reduction in the size of the aggregate exposed on the surface of concrete compared to other prior art methods. The resultant surface seeded exposed aggregate concrete exhibits an extremely flat exposed aggregate surface suitable for extremely high traffic flooring applications. Additionally, the surface texture and color are able to approximate the surface color and texture of more conventional flooring surfaces, such as stone, granite and marble.
U.S. Pat. No. 6,033,146 entitled GLASS CHIP LITHOCRETE AND METHOD OF USE OF SAME, hereby incorporated by reference in its entirety, discloses a surface seeded exposed particulate concrete and method for producing same. U.S. Pat. No. 6,033,146 improves upon the surface seeded aggregate concrete and method of making same disclosed in U.S. Pat. No. 4,748,788 by disclosing a method that produces surface seeded particulate concrete that expands the colors and surface texture appearances of concrete surfaces beyond those disclosed in U.S. Pat. No. 4,748,788.
The patents described above produce surface seeded exposed particulate concrete with desirable characteristics, as evidenced by the use and extensive licensing of such products throughout the United States. However, the application of the surface seeded particulate is a timely process. Furthermore, uniformity of application is difficult to achieve for large surface areas. Typically, it is difficult to achieve a uniform application for surface areas which require broadcasting of particulate beyond a distance of ten feet from the broadcaster.
Accordingly, there is a need for an improved process for surface-seeding of the particulate into the upper surface of a very large concrete slab.

Method of forming surface seeded particulate


A high frequency MOSFET device includes a Silicon-On-Insulator substrate. The MOSFET device has a source electrode connected to the substrate by a conductive region penetrating the insulator layer for dissipating heat from the drive section of an MOSFET to the substrate. The conductive region may be in a grid pattern or lattice configuration, surrounding the drive section of each MOSFET on the SOI substrate, opposite the source electrode of the MOSFET.

1. Field of the Invention
The present invention relates to a MOSFET device which operates at high frequencies, particularly to a MOSFET device on an SOI (silicon-on-insulator) structure substrate, and a method of manufacturing the MOSFET device.
2. Description of the Related Art
In a high-frequency prior art MOSFET, operation at high frequencies can be improved by connecting a P.sup.+ diffused region 19 to a P.sup.+ semiconductor substrate (sub-layer) 1, just below a source electrode as shown in FIG. 8, thereby decreasing source inductance and ON-state resistance. To improve the high-frequency characteristics further, it is desired that the high-frequency MOSFET use an SOI substrate in which a thin film semiconductor layer having a thickness of several tens of nanometers is disposed on an insulating layer on a semiconductor substrate 1. However, such an insulating layer on a silicon semiconductor substrate makes it impossible to form the P.sup.+ diffused region connecting the semiconductor substrate in the same way as in the prior art. In FIG. 8, numeral 10 denotes a gate oxide film, 11 denotes a gate electrode, 12 denotes a CVD inter-layer film, 14 denotes a P type channel layer, 15 denotes an N.sup.- type LDD layer, 16 denotes N.sup.+ type source and drain layers, and 18a and 18b denote a source electrode and a drain electrode, respectively.
In order to overcome the connection problem, it has been proposed in Japanese Patent Kokai Nos. 7-283414 and 9-45789 to form a conductive portion that penetrates the insulating layer and connects to the P.sup.+ type substrate 1, just below the source electrode.
However, manufacture of an integrated circuit based on silicon, having a high degree of integration and high performance, requires wiring for the conductive portion with strips several micrometers wide in the SOI-MOSFET. Etching of an Si trench several micrometers wide before forming wiring for the source and the drain is difficult.
An SOI substrate has a low thermal conductivity because an SiO.sub.2 layer is interposed as an insulating layer, so that it is not suitable for a high power output device, such as a high-frequency MOSFET, which generates heat.


The invention relates to bifunctional stapled or stitched peptides comprising a targeting domain, a linker moiety, and an effector domain, that can be used to tether, or to bring into close proximity, at least two cellular entities (e.g., proteins). Certain aspects relate to bifunctional stapled or stitched peptides that bind to an effector biomolecule through the effector domain and bind to a target biomolecule through the targeting domain. Polypeptides and/or polypeptide complexes that are tethered by the bifunctional stapled or stitched peptides of the invention, where the effector polypeptide bound to the effector domain of the bifunctional stapled or stitched peptide modifies or alters the target polypeptide bound to the targeting domain of the bifunctional peptide. Uses of the inventive bifunctional stapled or stitched peptides including methods for treatment of disease (e.g., cancer, inflammatory diseases) are also provided.

The important biological roles that peptides and proteins play as hormones, enzyme inhibitors, substrates, and neurotransmitters has led to the use of peptides and/or peptide mimetics as therapeutic agents. The peptide's bioactive conformation, combining structural elements such as alpha-helices, beta-sheets, turns, and/or loops, is important as it allows for selective biological recognition of receptors, enzymes, and nucleic acids, thereby influencing cell-cell communication and/or controlling vital cellular functions, such as metabolism, immune defense, and cell division (Babine et al., Chem. Rev. (1997) 97:1359). Unfortunately, the utility of peptides as drugs is severely limited by several factors, including their rapid degradation by proteases under physiological conditions, their poor cell permeability, and their lack of binding specificity resulting from conformational flexibility.
The alpha-helix is one of the major structural components of peptides. However, alpha-helical peptides have a propensity for unraveling and forming random coils, which are, in most cases, biologically less active, or even inactive, and are highly susceptible to proteolytic degradation.
Many research groups have developed strategies for the design and synthesis of more robust peptides as therapeutics. For example, one strategy has been to incorporate more robust functionalities into the peptide chain while still maintaining the peptide's unique conformation and secondary structure (see, for example, Gante, Angew. Chem. Int. Ed. Engl. (1994) 33:1699-1720; Liskamp, Red. Trav. Chim. Pays-Bas (1994) 113:1; Giannis, Angew. Chem. Int. Ed. Engl. (1993) 32:1244; Bailey, Peptide Chemistry, Wiley, New York (1990), 182; and references cited therein). Another approach has been to stabilize the peptide via covalent cross-links (see, for example, Phelan et al., J. Am. Chem. Soc. (1997) 119:455; Leuc et al., Proc. Natl. Acad. Sci. USA (2003) 100: 11273; Bracken et al., J. Am. Chem. Soc. (1994) 116:6432; Yan et al., Bioorg. Med. Chem. (2004) 14:1403). However, the majority of reported approaches involved the use of polar and/or labile cross-linking groups.
"Peptide stapling" is a term coined for a synthetic methodology used to covalently join two olefin-containing side chains present in a polypeptide chain using an olefin metathesis reaction (J. Org. Chem. (2001) 66(16); Blackwell et al., Angew. Chem. Int. Ed. (1994) 37:3281). Stapling of a peptide using a hydrocarbon cross-linker created from an olefin metathesis reaction has bee shown to help maintain a peptide's native conformation, particularly under physiological conditions (U.S. Pat. No. 7,192,713; Schafineister et al., J. Am. Chem. Soc. (2000) 122:5891-5892; Walensky et al., Science (2004) 305:1466-1470; each of which is incorporated herein by reference). This strategy has been applied to the apoptosis-inducing BID-BH3 alpha-helix, resulting in a higher suppression of malignant growth of leukemia in an animal model compared to the unstapled peptide (Walensky et al., Science (2004) 305:1466-1470; U.S. Patent Application Publication No. 2005/02506890; U.S. Patent Application Publication No. 2006/0008848; each of which is incorporated herein by reference).

Bifunctional stapled polypeptides and uses thereof

President and Fellows of Harvard College


A method of producing 3,5,5-trimethylcyclohexa-3-ene-1-one (.beta.-isophorone) including a catalyst of an oxide or mixed oxide of at least one element of the groups IIa, VIII, Ib, IIIa and Va of the periodic system. Isomerization is carried out without the addition of an organic base. The space-time yield in the production of .beta.-isophorone by the isomerization of .alpha.-isophorone is at a level suitable for an industrial application. .beta.-isophorone is especially suitable as an intermediate product for producing ketoisophorone.

.beta.-isophorone has great economic significance since it is an important synthetic structural element for the production of carotinoids, vitamins and pharmaceutical products. In particular, .beta.-isophorone is required as a precursor for ketoisophorone(2,6,6-trimethylcyclohex-2-ene-1,4-dione) and trimethylhydroquinone and therewith for the production of vitamin E. In addition, it is pivotably used in syntheses for odorous substances and natural compounds such as astaxanthine and abscisic acid and derivatives.
The production of isophorone is carried out by means of acetone trimerization under condensation of the C.sub.3 structural elements. The primarily formed isomer is .alpha.-isophorone since it has, in contrast to the .beta. isomer, a double bond conjugated to the keto function. For this reason the thermodynamic equilibrium is on the side of the .alpha.-isophorone; the .beta. concentration is only approximately 1-2% and the adjustment of equilibrium takes place very slowly.
Although there are basically two different preparations for arriving at ketoisophorone, namely, the direct oxidation of .alpha.-isophorone (.alpha.-IP).fwdarw.ketoisophorone (KIP) and the indirect route via the isomerization .alpha.-isophorone.fwdarw..beta.-isophorone (.beta.-IP) in a primary step and subsequent oxidation of the .beta.-isophorone.fwdarw.ketoisophorone, the latter process is clearly advantageous. Scheme 1 presents these considerations for ketoisophorone synthesis in a clear manner. ##STR1##
Numerous methods for the isomerization of .alpha.-IP have been described in the course of time which, however, have significant disadvantages. Viewpoints such as consumption of chemicals, poor space/time yields and problems in the workup have prevented, up to the present, a practical processing reaction on a rather large scale.
A distinction between gaseous phase reactions and liquid phase reactions can be drawn in the production methods for .beta.-IP from .alpha.-IP.
Basically, four parallel reactions of .alpha.-isophorone are possible in the gaseous phase which compete with one another and can be used to a varying degree as a function of the selected temperature range and of the nature of the surface of the catalyst used.
Isophorone can react in the following manner on contact in the gaseous phase:
a.) Isomerization to .beta.-isophorone PA0 b.) Reduction to trimethylcyclohexadienes (hydrogen required for this is supplied by isophorone (IP) decomposition accompanied by carbonization phenomena) PA0 c.) .beta.-Elimination of methane to 3,5-xylenol PA0 d.) Production of mesitylene. PA0 D1=A. Heymes et al., Recherches 1971, 18, 104 PA0 D2=FR-A-1,446,246 PA0 D3=DE-OS-24 57 157 PA0 D4=U.S. Pat. No. 4,005,145 PA0 D5=EP-A-0,312,735 PA0 D6=JP 87-33019 corresp. to HEI-1-175954 of Jul. 12, 1989.
The following scheme 2 shows the reactions of .alpha.-IP catalyzed upon heterogeneous contact in the gaseous phase: ##STR2##
EP 0,488,045 B1 discloses an isomerization method in the gaseous phase (300-450.degree. C.) with a heterogeneous catalyst. Oxides and mixed oxides of Mg (group IIa), Al (IIIa), Si (IVa) and Ni (VIII) are used as catalysts which are active per se or are applied on a .gamma.-aluminum oxide carrier (specific surface 1-50 m.sup.2 /g). 1-10 kg .alpha.-IP are used per liter catalyst, the concentration of the intermediately obtained solution is about 9% .beta.-IP, the final concentration after distillation in a vacuum is 97% .beta.-IP. The granulation of NiO takes place with 1% Luviskol K90 (-polyvinylpyrrolidone). This result corresponds, relative to the amount of catalyst used and the time, to a yield of Y=0.308 kg .beta.-IP per liter catalyst and hour. A disadvantage to this is the fact that only a 9% .beta.-IP mixture accumulates per hour. The space-time (S-T) yield Y.sub.S-T =0.09 1.sub..beta..sbsb.-IP /l.sub.solution relative to the educt volume used (example 1).
In addition, the rate of removal is low, which makes the method not very attractive on an industrial scale.
L. F. Korzhova, Y. V. Churkin and K. M Vaisberg, Petrol. Chem. Vol. 31, 1991, 678 describe the reaction of .alpha.-IP at 300-800.degree. C. in the presence of heterogeneous catalysts. .gamma.-Aluminum oxide, magnesium oxide and quartz are considered as catalytic systems. The product spectrum is observed as a function of temperature and of catalyst. The formation of .beta.-IP, trimethylcyclohexadiene, 3,5-xylenol and of mesitylene are compared with each other (see scheme 2: Paths a., b., c., d.). Thus, the thermal reaction of .alpha.-IP at above 550.degree. C. on a slightly developed catalytic surface (quartz) results in a mixture of the composition c>>a>>d and b=0. The reaction of the MgO contact at 400.degree. C. shows a similar product distribution at distinctly lower temperature, namely, c>>a>d>b. The reaction takes place at 300.degree. C. in the presence of an aluminum oxide catalyst with pronounced basic-acidic surface structure with a distinct preference given to the cyclohexadiene products, namely, b>>c>d.
On the whole, it can be assumed that a catalytic gaseous-phase isomerization is absolutely disadvantageous in several ways: It can be stated in general that these methods are disadvantageous because either the product formation is accompanied by a considerable accumulation of byproducts or the space-time yield (absolute .beta.-IP production/hkg.sub.cat) is too low.
A number of publications also relate to the isomerization in the liquid phase. The recent state of the art is represented by the following publications:
D1 discloses the isomerization of .alpha.-IP to .beta.-IP with stoichiometric amounts of MeMgX (Me=methyl; X=halogen) Grignard compound. 73% .beta.-IP is obtained under the evolution of methane in the presence of catalytic amounts of FeCl.sub.3. Mechanistic notions start with the assumption that the Grignard compound reacts as a base and does not function as the carrier of a carbanion. Excess Mg results in the production of dimer mixtures which proceed from a reductive metallic dimerization. However, the reaction of .alpha.-isophorone with molar amounts of methylmagnesium iodide in the presence of catalytic amounts of FeCl.sub.3, subsequent hydrolysis and workup by distillation is just as complicated as it is in the consumption of chemicals.
D2 relates to the isomerization of .alpha.-IP to .beta.-IP in the presence of catalytic amounts of p-toluene sulfonic acid and generally aromatic sulfonic acids, especially aniline sulfonic acid. The amount of the catalyst used is 0.1-0.2% relative to the (.alpha.-IP used. However, a low degree of conversion and a high accumulation of byproducts prevent an industrial application of the method of D2.
According to D3, the preparation of .beta.-IP takes place by means of boiling .alpha.-IP for several hours in triethanol amine, fractionation, washing the distillate with tartaric acid and sodium chloride solution. The consumption of chemicals is also considerable here.
In D4, acids with a pK=2-5 and a higher boiling point than .beta.-IP (boiling point .beta.-IP=186.degree. C./760 mm Hg) are used as catalyst. According to the patent claim the following are explicitly protected in the liquid phase:
Aliphatic and aromatic amino acids, adipic acid, p-methylbenzoic acid, 4-nitro-m-methylbenzoic acid, 4-hydroxybenzoic acid, 3,4,5-trimethoxybenzoic acid, vanillic acid, 4-trifluoromethylbenzoic acid, 3-hydroxy-4-nitrobenzoic acid and cyclohexane carboxylic acid and derivatives. The amount of catalyst used is 0.1-20 molar percent. The yield of .beta.-IP (relative to .alpha.-IP used) is 74.5%. This corresponds under the given conditions converted to the amount of catalyst used and time to a yield of Y=0.218 liters .beta.-IP per kilogram catalyst and hour.
The homogeneous catalytic isomerization of .alpha.-IP.fwdarw..beta.-IP with slightly dissociated acids represents an improvement as concerns the consumption of chemicals with .beta.-IP being continuously removed from the equilibrium. With so low a rate of removal as 11 ml/h .beta.-IP from an educt volume of approximately 0.5 kg .alpha.-IP, the space-time yield and the production of .beta.-IP with Y=0.24 kg .beta.-IP/kg.sub.cat are too low to be used in technological applications.
A similar principle is followed in D5. Acetyl acetonates of transitional metals are used as .pi. bond isomerization catalysts. Even Al (acac) displays catalytic activity. The use of the catalyst takes place in 0.01-10% by weight. Metallic catalysts of the groups IVb (Ti/Zr/Hf), Vb (V/Nb/Ta), VIb (Cr, Mo, W), VIIb (Mn/Tc/Re), of the entire group VIII and aluminum are patented. The primarily accumulating distillate has a .beta.-IP content of 94%, a further Vigreux distillation enriches the .beta.-IP content to 99%. This result corresponds, relative to amount of catalyst used and the time, to a yield of Y--9.4 liters .beta.-IP per kilogram catalyst and hour. This corresponds, relative to the educt solution used, to a yield of Y.sub.s-t =0.0376 l.sub..beta..sbsb.-IP /h/l.sub.solution.
Aside from the fact that the space-time yield is low and the accumulation of byproducts considerable, catalyst and distillation residue can not be readily separated in the homogeneous catalytic system used. Therefore, discarding is from time to time necessary since the temperature in the distillation bottom would otherwise rise too high. Even so, a "re-truing" of the temperature is required.
According to D6, the isomerization takes place in the liquid phase at temperatures around 200.degree. C. Silica gels with or without the addition of alkyl-substituted imidazolines of the following formula are used as catalyst. ##STR3##
Typical experimental conditions: 300 g .alpha.-IP and 25.7 g SiO.sub.2 are distilled for 52 h in the presence of refined steel; 230 g .beta.-IP (=76.6% yield) result with 99.0% purity. This result corresponds, relative to amount of catalyst used and the time, to a yield of Y=0.174 liters .beta.-IP per liter catalyst and hour.
However, the preparation of the organic bases is expensive and the space-time yield of the method low; with a characteristic value of Y=0.174 liters .beta.-IP/l catalyst per hour, even this method can not be converted to a technical scale. Relative to the volume of educt solution used the yield is Y.sub.s-t =0.0149 l.sub..beta..sbsb.-IP /h/l.sub.solution.
Moreover, the procedure described is unfavorable and the absolute production of .beta.-IP is low. The batchwise reaction and the performance of the isomerization reaction and pure distillation of the .beta.-IP in one step is especially disadvantageous. It can be demonstrated that the re-isomerization of .beta.-IP to .alpha.-IP occurs to a considerable extent on account of the high reaction temperature in the distillation apparatus.

Method of producing 3, 5, 5-trimethylcyclohexa-3-ene-1-one(.beta.-isophorone) by the isomerization of 3, 5, 5-trimethylcyclohexa-2-ene-1-(.alpha.-isophorone)


A magnetic tunneling junction (MTJ) cell includes a free magnetic layer having a low magnetic moment, and a magnetic random access memory (MRAM) includes the MTJ cell. The MTJ cell of the MRAM includes a lower electrode, a lower magnetic layer, a tunneling layer, an upper magnetic layer and an upper electrode, which are sequentially stacked on the lower electrode. The upper magnetic layer includes a free magnetic layer having a thickness of about 5 nm or less. The MTJ cell may have an aspect ratio of about 2 or less, and the free magnetic layer may have a magnetic moment of about 800 emu/cm3 or less.

1. Field of the Invention
The present invention relates to a semiconductor memory. More particularly, the present invention relates to a magnetic tunneling junction (MTJ) cell having a free magnetic layer with a low magnetic moment and a magnetic random access memory (MRAM) having the same.
2. Description of the Related Art
A magnetic random access memory (MRAM) consists of a transistor and a magnetic tunneling junction (MTJ) cell in which data is stored. A magnetoresistance (MR) ratio of an MTJ cell changes depending on magnetic polarization orientations of vertically stacked magnetic layers. The MRAM is a memory device that writes data using the characteristics of the MTJ cell.
In order to accurately read out data from an MRAM, it is preferable that the MRAM has as large a sensing margin as possible. The sensing margin is generally determined by the MR ratio of the MTJ cell.
In order to increase the MR ratio of the MTJ cell, stability and uniformity of the MTJ cell must be assured. For this purpose, a tunneling oxide layer of the MTJ cell must have a uniform thickness and stability of manufacturing processes must first be established.
In addition, the MRAM must assure selectivity, i.e., other MTJ cells adjacent to a selected MTJ cell must not be influenced during an operation of selecting the selected MTJ cell. In a well-known MRAM (hereinafter, referred to as "the conventional MRAM"), however, abnormal phenomena, such as an edge pinning and a vortex pinning, have been reported during writing or reading data to or from an MTJ cell.
Due to these phenomena, larger switching fields are demanded during the data read/write operation. This results in failed bits, i.e., MTJ cells which are not switched by a normal switching field during the data read/write operation.
FIG. 1 illustrates an edge pinning that occurs in a free magnetic layer during the data read/write operation of the conventional MTJ cell, and FIG. 2 illustrates a variation in hysteresis characteristics arising from the edge pinning.
FIG. 3 illustrates a vortex pinning that occurs in a free magnetic layer during the data read/write operation of the conventional MTJ cell, and FIG. 4 illustrates a variation in hysteresis characteristics arising from the vortex pinning.
In FIGS. 2 and 4, a reference symbol "▪" indicates a hysteresis characteristic when a magnetic field is applied, and a reference symbol "◯" indicates a hysteresis characteristic when no magnetic field is applied.
FIG. 5 illustrates a switching distribution of MTJ cells during the data write operation of the conventional MRAM, in which free magnetic layer is formed of CoFe/NiFe, here, a cobalt iron (CoFe) layer having a thickness of 10 Å and a nickel iron (NiFe) layer having a thickness of 30 Å. In FIG. 5, reference symbols C1, C2, C3 and C4 indicate ratios of failed bits, i.e., MTJ cells that are not switched in a normal switching field.
Referring to FIG. 5, the MTJ cells that are not switched in the normal switching field are switched in a switching field that is well above the normal switching field (C1, C2, C4), or are switched in a switching field that is well below the normal switching field (C3).
In the conventional MRAM, the degree of integration can be increased by forming a thinner magnetic layer of the MTJ cell, especially a free magnetic layer (CoFe/NiFe). As the free magnetic layer is thinner, however, thermal stability in the magnetic moment of the free magnetic layer may be degraded. This means that the MTJ cell is thermally unstable.

Magnetic tunneling junction cell having a free magnetic layer with a low magnetic moment and magnetic random access memory having the same


A computer implemented method for authoring a multimedia compact disc is provided. The method includes obtaining multimedia content from at least one source and enabling manipulation of the obtained multimedia content. The method further includes arranging the obtained multimedia content in a graphical hierarchical tree structure. The arranging of the multimedia content graphically defines the hierarchical arrangement relative to other multimedia content to be recorded to the multimedia compact disc.

1. Field of the Invention
The present invention relates generally to the recording of video, photo, and multi-media onto optical media, and more particularly to a method and apparatus for easily capturing and editing images and multi-media, and for authoring optical media containing video, photo, image, and other multi-media presentations.
2. Description of the Related Art
The convergence of photography, video, and motion picture industries with the computer industry is greatly expanding the photo, video, and other image options for the consumer. The use of optical media such as CD-R, DVD, and the like, is rapidly becoming a viable option for business as well as personal applications. By way of example of a business application, equipment manufacturers can record maintenance and service procedures, and then transfer the recorded procedures to optical media to ship with a tool to customers, or to ship to field technicians. Customer or support personnel can then simply play the optical media in a convenient computer system to observe and learn necessary procedures as correctly demonstrated. Personal applications include photo and video capture to create everything from photo albums to multi-media collections of movies, images, photos, and the like.
Although the possibilities for the use and application of video media seem limited only by the boundaries of the imagination, the technical expertise required to assemble, edit, and author DVD and other optical media containing collections and presentations of video, photographic, image, and multi-media data has kept the expansion of the market in check, and beyond the resource and skill of the average consumer.
Typical prior art video authoring programs tend to be limited in scope so that specialized functions are accomplished with different programs. By way of example, one program might be required to capture and edit video data, another program might be required to capture and edit photographic data, and another program required to collect the data in a presentation format. Further, some prior art programs offer only standard templates into which a user can insert video or photographic files with little or no option for personalization or modification. If a prior art program does provide for user modification, edit and display is typically restricted to one content file and one content file type at a time.
Prior art authoring software often presents technical barriers preventing wide general use and enjoyment. By way of example, structuring of the photo, video, or other image content is generally presented in abstract file and folder hierarchical format. The non-technical user has no visual representation of structure and format using actual photo, video, or other image content. The un-skilled user with little experience authoring DVD or VIDEO CD projects is provided no tools or visual reference to associate the abstract file and folder structure with the ultimate video, photo, or other image DVD. The difficulty of creating even the abstract structure that will be a presentation is compounded by requiring the user to navigate through a plurality of screens and functions that are generally arcane to the average consumer, and bear little or no resemblance to a DVD presentation that one can experience by simply inserting a disc into a DVD player connected to the home television set.
In view of the foregoing, there is a need for a method and apparatus and computer program for easily capturing and editing video, photographic, and other image data, and then authoring DVD, VIDEO CD, and Super Video CD presentations to be recorded to the optical media. The method, apparatus, and computer program should provide an average computer user an effective and intuitive interface to capture and edit video, photographic, and other image content from a plurality of sources, and to collect, structure, and arrange the selected content to author DVD, VIDEO CD, and Super Video CD presentations. The method, apparatus, and computer program should further provide the user with a visual, graphic workspace in which to arrange and create presentations and projects including a plurality of content and content formats that can be easily structured using common methods and commands familiar to the typical user.

Software methods for authoring multimedia content to be written to optical media