The disclosure herein describes managing defects in a model training pipeline. A synthetic data set is generated that is associated with a defect type and a lifecycle stage of the model training pipeline, and baseline performance metrics associated with the defect type are generated. Based on a code change to the pipeline, a test model is trained using the pipeline and the synthetic data set, and test performance metrics are collected based on the test model and associated with the defect type. Based on comparing the baseline performance metrics and the test performance metrics, a defect of a particular defect type is identified in the pipeline. An indicator of the defect is provided that includes the defect type and the lifecycle stage with which the synthetic data set is associated, whereby a defect correction process is enabled to remedy the defect based on the associated defect type and the lifecycle stage.

Machine learning-based models have become vital tools for many purposes, such as classifying data entries based on complex requirements, identifying patterns in very large data sets, processing image or video data to enable computer vision, and the like. Improving and automating the processes that are used to create and train such models are important areas that provide opportunities but that also present significant challenges. Much recent work on the subjects have focused on the selection of machine learning algorithms and tuning of parameters that are used in the processes. However, there are many different points in the model training lifecycle where changes can be introduced that result in degraded performance of the trained models, and are therefore considered defects. Identifying and correcting such defects requires significant time and manual effort by technicians, and increasing complexity of model training processes only increases the type and number of defects that may be introduced based on changes, further compounding the challenges of defect identification and correction.

Managing defects in a model training pipeline using synthetic data sets associated with defect types


The present invention provides a ball spline which enables the manufacturing of an outer cylinder to be done simply, the manufacturing cost to be reduced, and the loading of balls to be done easily. This ball spline comprises a slider fitted around a ball spline shaft so that the slider can be slid freely thereon, and so that rotational torque can be transmitted to the slider. In the slider, a retainer unit fitted in the outer cylinder is divided into two at the regions of direction changing passages, and rings provided with curved portions constituting guides for balls are fitted in the portions of the outer cylinder which are opposed to the regions of the direction changing passages. The rings are fitted between the outer cylinder and retainers.

1. Field of the Invention
This invention relates to a ball spline in which a slider is formed so that the slider can be slid via balls relatively to a ball spline shaft having longitudinally extending raceway grooves.
2. Description of the Prior Art
A ball spline adapted to moving a slider linearly along a ball spline shaft via balls held and rolling in retainers has been applied to an industrial robot and a transfer machine. A ball spline constitutes a linear motion guide bearing, and comprises an elongated ball spline shaft, and a slider freely slidable with respect to the ball spline shaft and adapted to receive rotary torque from the same.
A linear motion guide ball bearing is known as a retainer-carrying ball spline. This linear motion guide ball bearing comprises mainly an outer cylinder, retainers, balls as rolling elements, and snap rings. On the outer circumferential side of the retainers, circuit type circulating passages for circulating and guiding the balls are formed. An inner circumferential surface of the outer cylinder is provided with raceways on which the balls receiving a load roll, inclined surfaces for circulating the balls smoothly from the raceways to no-load escape sections, and ball return passage-forming circumferentially inclined curved surfaces (refer to, for example, Japanese Patent Laid-Open No. 187112/1984).
A ball retainer for linear bearings, comprising a retainer body, and an annuler member adjacent to the retainer body is known as a ball spline. This ball retainer for linear bearings is formed of a retainer body and an annular piece, the retainer body being provided with loaded ball guide grooves in ball rolling regions of raceways, the annular piece being provided with semicircular recesses, which are opposed to ball turning grooves formed at an end portion of the retainer body, for smoothly carrying out the circulating and guiding of the balls (refer to, for example, Japanese Utility Model Registration No. 2504812).
The ball spline disclosed in Japanese Patent Laid-Open No. 208469/1995 filed by the applicant of the present invention has a one-piece retainer fitted in an outer cylinder body and side rings, and end seals at both ends of the retainer. This ball spline need not be provided with ball retaining claws in the outer cylinder body, and the retainer can be positioned accurately in the axial and circumferential directions with respect to the outer cylinder body. The ball spline is provided with an axial slide stop and a rotation stop on the retainer. When the retainer turned during the assembling of the ball spline, until the axial slide stop has been brought into slide contact with both of the end surfaces of the outer cylinder body with the rotation stop having contacted a rotation stop surface of the outer cylinder body, the axial and circumferential positioning of the retainer with respect to the outer cylinder is attained. When the projections of the side rings are fitted in hollow spaces between outer surfaces of projecting portions of this ball spline and wall surfaces of recessed portions of the outer cylinder body, the retainer can be fixed with respect to the outer cylinder body.
In various types of ball splines described above, escape sections comprising inclined grooves are formed at both of axial ends of raceway grooves in ball loading regions of the outer cylinder so as to guide the balls moving in direction changing passages in the retainer. Therefore, it is difficult to form the raceway grooves, and the manufacturing cost increases. Regarding the outer cylinder, to which a retainer is fixed, in a conventional ball spline, the broaching thereof and the high-precision finishing of the raceway grooves thus formed in the outer cylinder are difficult to implement, and it is also troublesome to form retainer fixing portions on the outer cylinder. This causes the outer cylinder manufacturing cost to increase.


A method, executed in a microprocessor, for providing a shift-and-add mask, M=m.sub.1, m.sub.2, . . . , m.sub.N-1, m.sub.N, for a pseudo-noise sequence generator ("PNSG"). The PNSG generates a first pseudo-noise ("PN") code, and has N stages, each stage being at one of two states. The PNSG also has an associated shifter for generating a shifted PN code which is the same code as the first PN code, but delayed by K chips. The shifted PN code is generated as the inner product of the shift-and-add mask with the states of the stages of the PNSG. According to the inventive method, a value of K is provided, and it is determined whether K is 0. If K is 0, M is provided such that m.sub.N =1 and, for all n.noteq.N, m.sub.n =0. However, if K is not 0, it is determined whether K is greater than N. If K is greater than N, the remainder, R, of the division D.sup.K-1 /f(D), is determined, where EQU D.sup.K-1 =(m.sub.1 c.sub.1 +m.sub.2 c.sub.2 + . . . +m.sub.N c.sub.N)+(m.sub.2 c.sub.1 +m.sub.3 c.sub.2 + . . . +m.sub.N c.sub.N-1)D+(m.sub.3 c.sub.1 +m.sub.4 c.sub.2 + . . . +m.sub.N c.sub.N-2)D.sup.2 + . . . +m.sub.N c.sub.1 D.sup.N-1,. and EQU f(D)=c.sub.1 D.sup.N +c.sub.2 D.sup.N-1 + . . . +c.sub.N D+1.. Then, M is determined by setting EQU R=(m.sub.1 c.sub.1 +m.sub.2 c.sub.2 + . . . +m.sub.N c.sub.N)+(m.sub.2 c.sub.1 +m.sub.3 c.sub.2 + . . . +m.sub.N c.sub.N-1)D+(m.sub.3 c.sub.1 +m.sub.4 c.sub.2 + . . . +m.sub.N c.sub.N-2)D.sup.2 + . . . +m.sub.N c.sub.1 D.sup.N-1,. and determining the resulting values of m.sub.n. However, if K is not greater than N, M is determined by setting EQU D.sup.K-1 =(m.sub.1 c.sub.1 +m.sub.2 c.sub.2 + . . . +m.sub.N c.sub.N)+(m.sub.2 c.sub.1 +m.sub.3 c.sub.2 + . . . +m.sub.N c.sub.N-1)D+(m.sub.3 c.sub.1 +m.sub.4 c.sub.2 + . . . +m.sub.N c.sub.N-2)D.sup.2 + . . . +m.sub.N c.sub.1 D.sup.N-1,. and determining the resulting values of m.sub.n.

Pseudo-noise ("PN") codes are finding increasing application, for example in the area of wireless telephony. In code division multiple access telephony, for example, a digitized data stream is encoded using PN codes, to "spread" the spectrum of the signal transmitting the data. The digitized data stream is decoded using the same PN code used to encode it at the transmitter.
By illustration, FIG. 1 shows a block diagram of a portion of a code division multiple access ("CDMA") receiver unit. Specifically, FIG. 1 shows the functional blocks of a CDMA digital baseband functional unit 10 useful in understanding an application of the present invention. The blocks are implemented primarily in software running on a digital signal processor ("DSP").
Thus, there is shown an Energy Estimator unit 18, a Searcher 20, and a plurality of "Fingers" 22, each of which receives the two-wide input line 12 as an input. The outputs of the Energy Estimator unit 18, Searcher 20 and "Fingers" 22, are provided to other functional units represented collectively by block 24, such as, for reception, rate detection, symbol alignment, Viterbi decoding, etc., and, for transmission, encoding, interleaving, etc. Voice signals are provided on line 14 to block 24. Signals from Estimator unit 18 are provided on line 26 to block 24. Signals from Searcher 20 are provided on line 28 to block 24. Signals from Fingers 22 are provided on lines 30 to block 24. A Transmit Processing unit 32 receives encoded data signals on line 34. The output of Transmit Processing unit 32 is provided on line 16.
A PN Code Generator unit 36 provides PN code signals on line 38 to Fingers 22, and on lines 40 to Transmit Processing unit 32. The PN Code Generator unit 36 receives control signals on lines 42 from block 24, and it receives clock signals from a Clock Generator 44 on lines 46. Clock Generator 44 also provides clock signals on lines 48 for various other clocked functions in Functional unit 10.
As a general matter, in operation, functional unit 10 receives I and Q encoded data streams on two-wide input lines 12, provided from an RF front end unit (not shown), and performs various functions associated with CDMA reception, such as signal acquisition, rate determination, Viterbi decoding, digital-to-analog conversion, and the like. The I,Q encoded data is provided in the form of binary encoded sample values of the analog RF signal received at the RF front end, since the implementation of the functional unit 10 is in a software process executed using a DSP, which requires such binary encoded sample form for the data.
Functional unit 10 also receives voice signals on line 14, performs various transmission functions, such as analog-to-digital conversion and encoding, and provides I,Q coded, spread-spectrum signals on two-wide output line 16 for modulation and transmission by the RF front end unit.
Specifically, the binary encoded sample values, of I,Q coded data, on line 12 are provided to Energy Estimator 18, which performs various operations on the data to estimate the average envelope strength of the received signal, and provides the result on line 26 for further processing. The binary encoded sample values, of I,Q coded data, on line 12 are also provided to Searcher 20, which performs various operations on the data to identify received signals for allocation to one of the Fingers 22, the data for such selection being provided to block 24 on line 28. Finally, the binary encoded sample values, of I,Q coded data, are provided on line 12 to Fingers 22 where some binary encoded values are selected and used in a decoding operation using a PN code provided on line 38 by PN Code Generator 36 to determine whether the PN Code Generator code signal is at the proper timing to decode the signal on line 12.
The PN Code Generator 36 also provides PN code signals, on lines 40, to the Transmit Processing Unit 32, which uses such PN code signals to spread-spectrum encode the digitized voice data, which may be Walsh encoded, e.g., provided on line 34 from block 24. The spread-spectrum signal resulting from this process is provided on output line 16. The PN Code Generator 36 also includes a Mask Generator subunit 37, which generates a mask for use in immediate shifts of the PN Code Generator 36 output, as is discussed in detail hereinbelow.
All of the foregoing, in general, is well known in the spread-spectrum communications art. Further details of the various functional units of such a CDMA digital baseband functional unit 10, other than that of the PN code generator 36, are, therefore, not pertinent to an understanding of the present invention, and so, in the interest of clarity and brevity are not described in detail herein. The PN code generator 36, however, is pertinent, and is described further hereinbelow.
First, turning to a general discussion of PN codes, PN codes are generated by pseudo-noise sequence generators ("PNSGs"). One familiar apparatus used in PNSGs is a device known as a linear feedback shift register ("LFSR"). However, PNSGs are not limited to LFSRs. An PNSG is typically composed of a series of N stages, each stage including a memory element or memory step (depending on whether the PNSG is hardware or software), whose inputs are a linear combination (modulo 2) of the output memory element or step and previous memory element or step when viewed from a left-to-right perspective. The individual ones and zeros ("bits") of the output sequence of a PNSG, i.e., of a PN code, are sometimes referred to as "chips." A specific example of a PNSG 1 for N=4 is shown in FIG. 2. It will be understood that the PNSG 1 may be implemented in hardware, for example as an LFSR, or it may be implemented in software, for example for execution on a DSP, in which case FIG. 2 represents a structure for the logical flow of the method so implemented. Discussion below assumes software implementation.
In FIG. 2 can be seen the four memory steps 50, 52, 54, 56, as well as an addition step 58 disposed between memory steps 54 and 56. The output of memory step 50 is provided to the input of memory step 52, the output of memory step 52 is provided to the input of memory step 54, while the output of memory step 54 is provided to one input of addition step 58. The output of addition step 58 is provided to the input of memory step 56, with the output of the PNSG being the output 60 of memory step 56. A feedback path 60' is also provided from the output 60 of memory step 56 to the input of memory step 50 and to the other input of addition step 58.
The operation of the PNSG 1 shown in FIG. 2 can be described by either a state diagram or a table. The "state" of the PNSG 1 is the value of the bits stored in the memory steps before a given iteration. Thus, for PNSG 1, the state before iteration "n" may be expressed as S.sub.n =mnop, where m, n, o and p are the value of the bits stored in memory steps 50, 52, 54, 56, respectively. If the memory steps 50, 52, 54, 56, of PNSG 1 are initialized with the state S.sub.0 =0001, the output and subsequent states of the PNSG are as shown in Table 1:
TABLE 1 ______________________________________ Clock Cycle or Iteration State Output ______________________________________ 0 0001 1 1 1001 1 2 1101 1 3 1111 1 4 1110 0 5 0111 1 6 1010 0 7 0101 1 8 1011 1 9 1100 0 10 0110 0 11 0011 1 12 1000 0 13 0100 0 14 0010 0 15 0001 1 ______________________________________
With respect to Table 1, note that after the 15th iteration the state of the PNSG reaches that of the initial or 0th iteration. In fact, the output and state sequences of the PNSG repeat with a period of 15. For the case of N=4, this represents the maximum possible period since the all zeros state never occurs. Thus, in general, a PNSG is capable of generating a sequence of period (or, length) 2.sup.N -1, where N is the number of stages. Not all PNSG configurations generate a sequence with the largest possible period, but those that do are said to generate a maximal length sequence or m-sequence for short. For the purposes of the present invention, PNSGs that generate m-sequences are of primary interest and hence discussion herein is focused on PNSGs having this property.
Now, it is often desirable to generate a delayed version of a PN code relative to some master, or reference, sequence. While it is possible to use a simple delay line to accomplish this, it is frequently necessary to generate very long delays that cause this approach to become impractical.
A superior technique for generating a delayed PN code exploits the shift-and-add property of m-sequences. This property means that when a shifted or delayed version of a PN code is added to itself, the resulting code is merely a delayed version of the original. To better understand this, consider the following sequence generated by the PNSG 1 of FIG. 2:
. . 111101011001000 . . . . PA0 . . 011110101100100 . . . . PA0 . . 100011110101100 . . . ,
If this sequence is shifted or delayed by one chip, the result is
Adding these two sequences together using modulo 2 arithmetic yields
which is merely the original PN sequence delayed by 4 chips. While other specific delays can be generated in this fashion, a more efficient and sophisticated method is described next.
Referring to the State column in Table 1, notice that the sequence associated with a particular stage represents a delayed version of the PNSG output. E.g., the sequence corresponding to the least significant bit of the state vector is identical to the output; the sequence corresponding to the most significant bit is the output delayed by one chip, etc. Thus according to the shift-and add property of m-sequences, another PN code having a specific delay relative to the original sequence can be generated by adding together one or more outputs of the four stages.
FIG. 3 shows a PN sequence generator having a PNSG 1, similar to the arrangement of FIG. 2, but also having an associated PN shifter 62. As in FIG. 1, four memory steps 50, 52, 54, 56, an addition step 58, an output 60 and a feedback path 60' are provided, interconnected as in FIG. 2. Also provided, however, is shifter 62. The shifter 62 is comprised of an additional four memory steps 64, 66, 68, and 70. These receive a PN shift-and-add mask value over an input 72. The output of memory step 64 is provided to one input of a first multiplier 74. The other input of multiplier 74 is the output of memory step 50. The output of memory step 66 is provided to one input of a second multiplier 76. The other input of multiplier 76 is the output of memory step 52. The output of memory step 68 is provided to one input of a third multiplier 78. The other input of multiplier 78 is the output of memory step 54. The output of memory step 70 is provided to one input of a fourth multiplier 80. The other input of multiplier 80 is the output of memory step 56.
The output of multiplier 74 is provided to one input of a second addition step 82. The output of multiplier 76 is provided to the second input of addition step 82, while the output of addition step 82 is provided to one input of a third addition step 84. The output of multiplier 78 is provided to the second input of addition step 84, while the output of addition step 84 is provided to one input of a fourth addition step 86. The output of multiplier 80 is provided to the second input of addition step 86. The output 88 of addition step 86 provides the same sequence as the output 60 of the PNSG 1, but delayed by an amount determined by the value of the shift-and-add mask stored in memory steps 64, 66, 68, and 70.
Thus, by forming the inner product of a shift-and-add mask, hereinafter simply referred to as a "mask," stored in the memory steps 64, 66, 68, 70, with the states of the PNSG, stored in the memory steps 50, 52, 54, 56, as shown in FIG. 2, a second sequence can be generated with a known delay relative to the PNSG output. This second sequence is, as mentioned above, provided at the output 88 of addition step 86.
However, a problem that exists in the practical application of the use of a mask for accomplishing rapid shifts of PN sequences is in the time it takes to generate the mask itself. For example, PN sequence generators are currently being used in code division multiple access ("CDMA") cellular telephone applications. Data rates in such applications are high. Rapid shifts in the PN sequences generated in such applications must also be rapid. Therefore, there is a need for a method and apparatus for generating a mask rapidly, yet controllably and accurately.

Method for providing offset mask for pseudo-noise sequence generator


A radio frequency (RF) tuner includes a programmable tracking filter bank receiving an RF input and outputting a filtered RF signal. A mixer stage receives the filtered RF signal and outputs a first quadrature component of the filtered RF signal and a second quadrature component of the filtered RF signal. Two variable gain amplifiers receive the first and second quadrature components and output amplitude-controlled I and Q components of the filtered RF signal. In one embodiment, the programmable tracking filter bank includes a plurality of tank circuits each connected to the RF input through an impedance. Each tank circuit include an inductor and a capacitor connected in parallel thereby forming an LC network, and a plurality of switched capacitors in parallel with the LC network and switched in and out of the tank circuit by programmable switches. In another embodiment, the programmable tracking filter bank includes a plurality of peaked low-pass circuits each connected to the RF input through an impedance. Each peaked low-pass circuit includes a capacitor connected to ground, and a plurality of switched capacitors in parallel with the capacitor and switched in and out of the peaked low-pass circuit by programmable switches.

1. Field of the Invention
The present invention relates to radio frequency (RF) receivers, and more particularly, to RF receivers with tracking filter banks for single conversion broadband filters.
2. Description of the Related Art
Direct-conversion, or homodyne, receivers are popular for many communications applications because of their simplicity and low power. They do not require intermediate-frequency (IF) filters, which are often costly, and need only one frequency conversion stage and one local oscillator (LO).
Direct-conversion receivers rely entirely on quadrature mixing to obtain the necessary image rejection. Single-conversion low-IF receivers for broadband communication systems, such as direct broadcast satellite (DBS), broadcast or cable television (CATV), may rely on some combination of quadrature conversion and pre-selection with tracking or switched filters.
Double-conversion receivers for these applications rely more on IF filtering for image rejection. Because the IF frequencies can be fixed, very sharp filters, such as surface acoustic wave (SAW) filters, need to be used. However, these filters are relatively costly.
Difficulties in integrating tracking filters and in achieving the necessary degree of image rejection through quadrature balance have heretofore prevented the implementation of integrated direct-conversion receivers for broadcast television and CATV. Integrated single-conversion low-IF tuners generally do not include the tracking filters.
A typical conventional single-conversion tuner is illustrated in FIG. 1. As shown in FIG. 1, the conversion tuner includes a bank of bandpass filters 101a, 101b, 101c (in this example, three filters) that receive RF input. The output of the bandpass filters 101 is fed into a low-noise amplifier 104, and then to a mixer 109. The tuner also includes a phase-lock loop (PLL) 120, which is comprised of a phase-lock loop controller 105, and voltage controlled oscillators (VCO's) 106a, 106b, 106c. Each VCO 106 is matched to a corresponding bandpass filter 101. The output of a phase-lock loop controller 105 controls the filters 101 and the voltage control oscillators 106. The outputs of the VCOs 106 are also inputted into the mixer 109.
As further illustrated in FIG. 1, the output of the mixer 109 is received by a variable gain amplifier (VGA) 110, which is placed in a feedback loop that includes a power detector 111. The output of the variable gain amplifier 110 then is inputted to a downstream demodulator (not shown in FIG. 1).
Thus, each tracking filter 101 is slaved to a corresponding voltage-controlled oscillator (VCO) 106a, 106b, 106c, which produces the local oscillator (LO) for the first frequency conversion when that filter 101 is selected. The choice of filter 101 and VCO 106 depends on the frequency of the desired channel, and is determined by a digital command. By using matched components, such as inductors, capacitors, and voltage-variable capacitors (varactors) in the VCO 106 and filter 101, the center frequency of each filter 101 can be matched to the frequency of the corresponding VCO 106. This arrangement is illustrated in FIG. 2.
As shown in FIG. 2, each bandpass filter 101 can include an inductor L205, a capacitor C207, a varactor diode D208, and a capacitor C206, connected as shown. Choke inductors L204 are used to prevent leakage of RF signals back upstream. As further shown in FIG. 2, the voltage control oscillator 106 includes active components 202, and passive components L210, C212, D213, and C211, connected as shown. A choke L209 similarly prevents leakage of RF signals back upstream from the VCO 106.
A secondary problem in direct-conversion tuners are the responses at the LO harmonics, as shown in the bottom graph of FIG. 1. For a narrowband communication system, where the input spectrum spans less than one octave, this is not a problem. There are no signals to be received at the frequencies corresponding to the LO harmonics. Any unwanted signals can in principle be removed with a fixed filter. But for wideband communication systems such as CATV and terrestrial broadcast television, this issue must be addressed. For example, for a TV channel at 50 Mhz, there is an unwanted harmonic response at 150 Mhz, as shown in FIG. 1.

Integrated tracking filters for direct conversion and low-IF single conversion broadband filters


A printing apparatus that conveys a printing medium placed on a surface of a conveyor belt, and performs printing to the printing medium by ejecting a liquid from a liquid ejection head, the apparatus includes: a magnetic recording layer that is formed to the conveyor belt as a continuous strip; a magnetic reproduction head that is disposed opposing the magnetic recording layer of the conveyor belt; and a control unit that detects recording details reproduced from the magnetic recording layer by the magnetic reproduction head. In the printing apparatus, the magnetic recording layer is recorded with the recording details about a magnetic pole change of a predetermined pattern, and is partially recorded with the recording details about a magnetic pole change different from the change of the predetermined pattern, and the control unit detects a movement status of the conveyor belt from any of the recording details reproduced from the magnetic recording layer by the magnetic reproduction head specifically about the magnetic pole change of the predetermined pattern, and detects a reference position of the conveyor belt therefrom specifically about the magnetic pole change different from the change of the predetermined pattern.

1. Technical Field
The present invention relates to a printing apparatus and a printing medium conveying apparatus that print any predetermined text, images, and others or a printing medium by forming minute particles (dots) thereon through ejection of a small amount of liquid from a plurality of nozzles.
2. Related Art
With the reason of the relatively inexpensive price and the ease of achieving high-quality color printing, an inkjet printer being an example of such a printing apparatus has become widely popular not only for office use but also for personal use with the spread of personal computers, digital cameras, and others.
Such an inkjet printer generally creates any desired printed matter with minute ink dots formed on a printing medium. More in detail, a moving element referred to as carriage or others includes an ink cartridge and a printing head (liquid ejection head) as a piece. Such a moving element ejects a liquid ink from a nozzle formed to the printing head while moving back and forth on the printing medium in the direction orthogonal to the direction of conveying the printing medium so that small ink dots are formed on the printing medium. If the carriage is provided with ink cartridges of four colors, i.e., black, yellow, magenta, and cyan, and their each corresponding printing heads, full-color printing becomes easily possible in addition to monochrome printing.
With an inkjet printer of a type using no carriage but a printing head of the length same as the width of the printing medium, there is no need to move the printing head in the width direction of the printing medium. This accordingly enables printing with a so-called single path, thereby favorably leading to high-speed printing as can be with laser printers. Note here that the inkjet printer of the former type is generally referred to as "multi-path (serial) inkjet printer", and the ink jet printer of the latter type as "line-head inkjet printer".
A line-head inkjet printer is often configured to place a printing medium on a conveyor belt for conveying. With such a configuration of placing a printing medium on a conveyor belt for conveying, to achieve printing with high image quality through ejection of a liquid ink onto an incoming printing medium from the printing head, there needs to detect the position of the printing medium with good accuracy. For this purpose, generally, the conveyor belt is provided with a mark for detection of the movement status, i.e., movement amount and speed such as linear scale. The mark is read by an encoder so that the position of the conveyor belt is detected, and from the detected position of the conveyor belt, the position of a printing medium is detected. For such detection, however, there needs to set a reference position for the conveyor belt for use as a position reference for the printing medium because the conveyor belt is generally endless. In consideration thereof, with an inkjet printer described in JP-A-2006-96429, a conveyor belt is provided with a tab for use as a position reference of the conveyor belt through detection thereof by a sensor, and control is so exercised as to place a printing medium not on the seam of the belt.
The problem with the previous technology typified by JP-A-2006-96429 is that there needs to include two sensors, i.e., a sensor for detecting the movement status of the conveyor belt, and a sensor for detecting the reference position of the conveyor belt, thereby complicating the configuration and increasing the cost.

Printing apparatus and printing medium conveying apparatus


An aluminum nitride (AlN) sintered product with a high thermal conductivity of 120 W/m.multidot.k or above can be produced at a relatively low sintering temperature of 1650.degree. C. or below in accordance with the following process of the present invention. That is, an A1N powder having a specific surface in a region of about 3.5 to 8 m.sup.2 /g and an oxygen content between 0.5 to 1.8 wt % is mixed with optimum additive amounts of sintering aids (I) to (III) to obtain a mixture powder. The sintering aid (I) is at least one selected from the group consisting of rare earth oxides and rare earth compounds which are converted to corresponding rare earth oxides by the sintering. The sintering aid (II) is at least one selected from the group consisting of alkaline earth oxides and alkaline earth compounds which are converted to corresponding alkaline earth oxides by the sintering. The sintering aid (III) is at least one selected from the group consisting of LAB.sub.6, NbC, and WB. The optimum additive amount of LaB.sub.6 is in a range of 0.05 to 3 wt % of the A1N sintered product. The mixture powder is compacted, and then sintered at the sintering temperature in a non-oxidation atmosphere to obtain the A1N sintered product.

1. Field of the Invention
The present invention is directed to a process for producing an aluminum nitride sintered product with a high thermal conductivity at a relatively low sintering temperature.
2. Description of the Prior Art
Aluminum nitride (AlN) is an excellent material having a high thermal conductivity, insulation resistance and a low thermal expansion coefficient, etc. However, since aluminum nitride is a covalent bonding compound, it is difficult to produce a pure aluminum nitride sintered product without utilizing sintering aids or a hot-press sintering method.
U.S. Pat. No 4,746,637 discloses that a combination of Y.sub.2 O.sub.3 and CaO as sintering aids. That is, a mixture of an AlN powder and the sintering aids is densely sintered at a temperature of 1650.degree. C. or above to obtain an AlN sintered product. However, thermal conductivity of the AlN sintered product is only 100 W/m.multidot.k or less. For using as a substrate in a power module, etc., an AlN sintered product having a high thermal conductivity of 120 W/m.multidot.k or more is desired.
Japanese Early Publication [KOKAI]No. 03-146471 discloses that a combination of Y.sub.2O.sub.3 and LaB.sub.6 is utilized as the sintering aids. In addition, Japanese Early Publication [KOKAI]No. 03-197366 discloses that a combination of CaO and LaB.sub.6 is utilized as the sintering aids. Though AlN sintered products obtained by using these combinations of the sintering aids show a high thermal conductivity, a high sintering temperature of 1900.degree. C. or above is required, so that it is necessary for expensive high temperature sintering furnace and fittings such as a setter capable of using at the high temperature. Additionally, there has been a problem of an expensive energy cost for producing the AlN sintered products.
In case of utilizing the hot-press sintering method for producing the AlN sintered product, though the sintering temperature can be lowered, a size or shape of the AlN sintered product would be limited.

Process for producing an aluminum nitride sintered product


An electret condenser microphone includes a housing, a diaphragm disposed within the housing, first and second sound inlet ports and an acoustic resistive material disposed within the housing and in the acoustic path between the second inlet port and the diaphragm. The acoustic resistive may further electrically couple a backplate coupled to the diaphragm to an amplifier disposed within the housing.

Unidirectional electret condenser microphones (ECM"s) typically include a housing, a diaphragm and a ring assembly, a backplate, and a spacer separating the diaphragm and ring assembly from the backplate. The ECM may also include an amplifier that may be disposed on a printed circuit board electrically coupled to the backplate. These components are mounted within the housing. One way in which ECMs operate is by allowing acoustic vibrations to enter the housing and allowing the diaphragm to vibrate in response thereto. The vibrating diaphragm causes a capacitance change between the diaphragm and the backplate that may be detected as an electrical signal. The electrical signal is coupled to the amplifier by a suitable conductor, such as wire, to produce an output from the ECM.
Typically, the unidirectional ECM should provide a high performance and control so that the sound coming from the front of the microphone is reinforced and the sound coming from the back is canceled. A unidirectional ECM may be made directional in order to enhance the performance with respect to sound coming from the front of the microphone by adding a second sound inlet port, such that there is one at the front and one at the back of the ECM. The sound entering from the front of the microphone goes directly to the diaphragm. The sound entering from the back of the microphone is delayed by a resistive/capacitive (RC) acoustic network. This delay is made so that the sound coming from the front of the microphone is reinforced and the sound from the back is cancelled.
To implement the RC acoustic network, an acoustic resistive material may be disposed between the second sound inlet port and the diaphragm. This material may be made of sintered plastics, plastic felts, laser drilled disks, and the sound is made to travel through the material perpendicular to a plane of the material. That is, the material is typically provided in the form of a sheet or layer having a first surface and a second surface. The sound is then made to travel substantially perpendicular to the first and second surfaces.
This arrangement of the acoustic resistive material has several disadvantages. The acoustic resistive materials often have a relatively large amount of variability that has a great effect on the directional performance of the microphone, with laser drilled disks providing the least amount of variability of the currently available materials but at higher cost. Also, the physical volume of the material places limits on the size of the ECM making size reductions difficult.
Accordingly, there is a need for an ECM that is inexpensive, simple to manufacture and scalable to relatively small sizes.


A system and method for generating a key list structure forming a queue of users' work flow requests in a queuing system such that many requests from a single user will not prevent processing of requests from other users in the queuing system. The key list structure comprises keys associated with users' work flow requests, each key indicating a priority level associated with a request, a user identification (User ID) associated with a requestor, and, an assigned user priority value (UPV). The method assigns UPVs to user requests in a manner such that user request entries become interleaved in the key list structure to prevent a single user from dominating the request processing.

1. Field of the Invention
The present invention relates generally to computing systems involving a queue for accommodating multiple user requests, and particularly, to a novel method for handling process requests in a manner that prevents starvation of a user's request.
2. Discussion of the Prior Art
Priority queuing schemes are used in computing environments where certain requests are deemed to be of more importance than other requests.
For example, a particular environment may be established such that priorities are assigned to requests based on whether the requester is waiting for the request to complete before continuing processing (synchronous), or if the requestor will not wait for the request to complete before processing other work (asynchronous). Synchronous requests may be assigned a priority 100 and "no wait" requests are assigned a priority 50. Thus, when a request is submitted, it is placed on the work queue based on the priority of the request. Synchronous requests are placed at the head of the queue to be selected first, and asynchronous requests are placed at the tail of the queue to be processed only after all synchronous requests have been processed.
In such systems that implement a queue to process work requests, queue entries are generally placed on the queue in FIFO order or according to some designated priority. When a work request is being selected, the processor simply removes an entry from the Head/Tail of the queue. If a single user submits a large number of requests, and then a second user (of equal importance or priority) submits subsequent requests, then the second user's request undergoes processor starvation since it is unable to have any of its requests processed until all of the requests of the first user are completed. In this scenario, the FIFO queue creates a situation of unfairness by allowing a single user to dominate request processing and not allowing other requests from other users to be processed, even though all of the requests have equal priority.
While algorithms exist today that implement round robin using different physical queues, link lists, etc., none of these systems present a system for interleaving requests based on keys in a constrained environment. For example, IBM's Data Facility Storage Management Subsystem: Hierachical Storage Manager (DFSMShsm) (an element of the DFSMS/MVS software storage solution for the OS/390 and z/OS IBM mainframe operating systems), is a disk storage management and productivity tool for managing low-activity and inactive data. It provides backup, recovery, migration, and space management functions as well as full function disaster recovery. DFSMShsm improves disk use by automatically managing both space and data availability in a storage hierarchy by implementing a link list and organizing requests on that queue. Thus, when placing a new request, the system begins at the head of the queue and traverses the queue until an appropriate location for the new request is found based on the priority and the requestor. For example, if one person submits a new synchronous request, then the queue would have to be traversed until that person's last existing synchronous request, or until a person is found with the next lower priority. The worst case scenario is that the entire length of the queue must be traversed before finding the placement location for the new request.
Thus, it would be highly desirable to provide some fairness to the queuing system so that a single user can not dominate the processor while other users have to wait for the first user's requests to be complete.
It would be further highly desirable to provide a system and methodology for sorting such requests based on the submitter such that requests from different users are interleaved so that no one user has all of their requests selected for processing while other users' requests have to wait.

System and method for processing multiple work flow requests from multiple users in a queuing system

International Business Machines Corporation


A dual in-situ mixing approach for extended tuning range of resonators. In one embodiment, a dual in-situ mixing device tunes an input radio-frequency (RF) signal using a first mixer, a resonator body, and a second mixer. In one embodiment, the first mixer is coupled to receive the input RF signal and a local oscillator signal. The resonator body receives the output of the first mixer, and the second mixer is coupled to receive the output of the resonator body and the local oscillator signal to provide a tuned output RF signal as a function of the frequency of local oscillator signal.

A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonance frequencies, with greater amplitude than at others. Resonators can be used in, for example, crystal oscillators (also known as quartz oscillators), inductance-capacitive (LC) oscillators, resistance-capacitive (RC) oscillators, and Microelectromechanical systems (MEMS) oscillators, also referred to as micromechanical MEMS oscillators. A crystal oscillator is an electronic circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. Crystal oscillators, such as quartz oscillators, are commonly used to generate frequencies to keep track of time (as in quartz clocks) or to generate a clock signal for digital integrated circuits. Usually, a different crystal is required for each desired frequency. Also, the crystal and the oscillator circuit compliments are typically distinct from one another, i.e., they are not integrated.
Resonators can also be used to select specific frequencies from a signal. Resonators can also be used in filters, such as in a quartz filter (also referred to as a crystal filter), or other piezoelectrics. Quartz resonators, for example, can directly convert their own mechanical motion into electrical signals. Quartz crystal filters have much higher quality factors than LCR filters (also referred to as a resonant circuit, tuned circuit, or RLC circuit) that has a resistor (R), an inductor (L), and a capacitor (C). These filters can be used in RF communication devices, for example, the quartz filter can be used in the intermediate frequency (IF) stages of a radio receiver. The quartz filter can be used for a fixed IF stage frequency because it has a very precise fixed frequency.
In general, electronic filters are electronic circuits which perform signal processing functions, specifically intended to remove unwanted signal components and/or enhance wanted ones. Electronic filters can be passive or active, analog or digital, discrete or continuous, linear or non-linear. The most common types of electronic filters are linear filters. One type of filter is a surface acoustic wave (SAW) filter, which is based on the transduction of acoustic waves. The transduction from electric energy to mechanical energy, in the form of SAWs, is accomplished by the use of piezoelectric materials. In particular, electrical signals are converted to a mechanical wave in a piezoelectric crystal. This wave is delayed as it propagates across the crystal, before being converted back to an electrical signal by further electrodes. The delayed outputs are recombined to produce a direct analog implementation of a finite impulse response filter. This hybrid filtering technique is also found in an analog sampled filter. Electronic devices, employing the SAW, typically utilize one or more inter-digital transducers (IDTs) to convert acoustic wave to electrical signal and vice versa utilizing the piezoelectric effect of certain materials, such as quartz. SAW filters are commonly used in radio-frequency (RF) applications, such as mobile telephones. These SAW filters may provide significant advantages in performance, cost, and size over other filter technologies such as quartz crystals (bulk wave), LC filters, and waveguide filters.
Tuning the center frequency of resonators and filters over a wide range can be difficult. For example, the MEMS resonator frequency is generally sensitive to electrostatic bias voltage, stress and any type of external force applied as control input. The higher the frequency the less sensitive the structure is to external forces, and the more difficult it is to pull its frequency.
Frequency pulling mechanisms are used to trim the frequency accuracy of oscillator and filters, to compensate for any type of drift including temperature, and to serve as a control mechanism for voltage controlled oscillators. These frequency pulling mechanisms may be, for example physical trimming, capacitive pulling, electrostatic pulling, stress or temperature control, or complex closed loop systems with multiple oscillators. For example, in oscillator applications, one can rely on the pulling effect of load capacitor. In such cases, the resonator mechanical frequency remains the same but the oscillator frequency is tuning over a very small range. For example, for quartz based oscillators, this capacitive load is used for temperature compensation and accurate trimming of the center frequency. In the case of MEMS oscillators, additional control can be exercised through the resonator DC Bias voltage (Vp) which creates an electrostatic pulling force. The pulling is directly proportional to the mechanical stiffness of the resonator. So, for a given control voltage range, the frequency pulling range will be reduced as the resonator increases in frequency. This control voltage can be used for trimming and temperature compensation.
Designs can be implemented to rely on stress dependence or temperature dependence of mechanical resonators to exercise a control over their center frequency. Physical trimming (etch, deposition) is used to bring the accuracy of resonator inside the specification range, especially for filters (quartz, thin Film Bulk Acoustic Resonator (FBAR), Bulk Acoustic Wave (BAW), MEMS, or the like.). More complex techniques for trimming and compensation of output oscillator at higher frequency have been introduced more recently. They rely on closed loop systems, like Fractional-N PLL or digital frequency discriminator where the main oscillator is locked to a reference oscillator, and their frequency ratio is control digitally. Other approaches may include electrostatic pulling in open-loop configuration, encapsulation of the device into micro-oven to keep temperature constant during fabrication, mechanical compensation of temperature drift, and Fractional-N PLL with reference drifting.
It should be noted that traditional electrostatic pulling is not effective in high-frequency MEMS oscillators. High-frequency MEMS resonators, such as MEMS resonators having approximately 1 MHz frequency or greater, for example, have a very high equivalent stiffness that causes them to have a very small electrostatic frequency pulling range. In MEMS oscillators, capacitive pulling, like used in quartz-based oscillators, may also not be effective to adjust the output frequency for both initial accuracy and temperature stability due to extremely small effective capacitance of the MEMS resonators.

Dual in-situ mixing for extended tuning range of resonators


Boron-containing network sulfide glass which may be useful in IR transmitting applications, such as IR optics, laser or fiber amplifiers doped with rare earths with emission in the near IR, and methods of making the same.

Field
Embodiments relate generally to boron-containing network chalcogenide glass and more particularly to boron-containing network chalcogenide glass which may be useful in IR transmitting applications, such as IR optics, laser or fiber amplifiers doped with rare earths with emission in the near IR, and methods of making the same.
Technical Background
Boron (B) is an extremely useful component of many oxide glasses, including borosilicates, boroaluminosilicates, borophosphates, etc. In the case of silica-containing glasses, B is used as a flux to lower melting/forming temperatures as well as to provide excellent thermal shock resistance through reduced thermal expansion coefficients. In the case of phosphate glasses, B tends to associate with P as a next nearest neighbor, forming coupled BO4/PO4 tetrahedra, which leads to increased polymerization of the glass network and improved durability of the glass.
Although B could be a useful component in tailoring the properties of chalcogenide glass, e.g. to reduce thermal expansion or perhaps to improve chemical durability, there are few reports of B-containing chalcogenide glass. Most of the B-containing glasses that have been reported to date are B sulfide (B2S3) and the so-called alkali thioborates, i.e. glasses comprising B2S3 and an alkali sulfide such as Na2S, all of which are characterized by poor durability. B-containing AgGe sulfide glasses have been described with a passing reference to some unmodified network glasses comprising B2S3 and GeS2. Save for the latter, there are no literature citations for B-containing network chalcogenide glasses, e.g. glasses based on P, Ga, Ge, As, In Sn and Sb sulfides, selenides or tellurides, other than for pure vitreous B2S3, presumably due to the fact that such glasses are typically prepared by melting mixtures of the constituent elements within evacuated fused silica vessels. As B is extremely refractory (Melting Point>2000° C.) as well as very reactive with O, it is very slow to dissolve and has a tendency to react with the container walls, thereby introducing Si and/or O into the resultant melt/glass. There is a need to develop B-containing network chalcogenide glasses, for example, B-containing network sulfide, selenide, and selenotelluride glasses and also methods to overcome the latter practical difficulties.


The present invention discloses a bat having an interchangeable handle portion and barrel portion. The handle portion has a first end and a second end. The barrel portion has a proximal end and a distal end, the proximal end abuttable to the second end of the handle portion. A tie rod received by the handle portion and the barrel portion, the tie rod having an alpha end and a beta end, the alpha end placible proximal the first end of the handle. An end cap placible proximal the distal end, the end cap releasibly attached to the beta end of the tie rod.

The present invention relates generally to an implement used for playing diamond sport and, more particularly, to a bat with interchangeable handles and barrels.
It will be appreciated by those of ordinary skill in the art that in the diamond sports, high performance bats are desired. It will further be appreciated that high performance bats also come at a considerable price. It will also be appreciated that the best bat for a particular person depends upon the weight of the bat, the length of the bat, how the weight is distributed, the material from which the bat is made, whether it is a single wall or shell bat, and other factors. Further, the best bat for an individual at bat varies based upon the type of ball used, the desired optimal result of the bat, the temperature, and other factors. This causes an individual player to own many bats and teams to own many more bats. Different softball associations require bats to meet different performance standards. Further, players like to use one bat for batting practice and another bat for game situations.
Further, it should be appreciated by one of ordinary skill in the art that different parts of a bat wear out for different reasons and at different times. For example, the barrel or ball striking portion of the bat tends to deflect when contacting the ball. Over time, this repeated deflection creates deformations. These deformations cause failure. As a result, the barrel on a bat may fail leaving the handle functional. To this end there have certain attempts to provide separate handle and barrels. Unfortunately, these separatable bats adversely effect the performance of the bat.
US Patent Application Publication No. US 2003/0069095 filed Apr. 10, 2003 disclosed a handle threadibly attached to a taper section and threadibly attached to a barrel section. Unfortunately, this direct threadible attachment creates many issues. Initially, the threaded portions will be the weakest sections of the fixed beam resulting in failure at the threaded portions. Likewise, U.S. Pat. No. 5,409,214; U.S. Pat. No. 6,511,392; U.S. Pat. No. 6,432,006; U.S. Pat. No. 5,820,438; U.S. Pat. No. 4,907,800; and U.S. Pat. No. 3,955,816 disclose pieces that are threadibly attached together or attached with very short threaded dowels or bolts. Other inventions such as those disclosed in Pub. No. US2003/0144089 and U.S. Pat. No. 4,819,935 use an internally threaded spine to hold the pieces together or to adjust the positions of the various pieces. U.S. Pat. No. 3,877,698 uses an internal dowel with grooves. In each of these cited patents and published applications, the inventor uses internal threading. This is difficult to achieve and adds much cost to the product. Further, the combined threads are likely to wear our over time. More importantly, none of these configurations appear to be useable in connection with a bat having a shell.
What is needed then is a bat with interchangeable handle and barrel. This needed bat allows the user to rapidly change handles, tapers, and barrels. This needed bat must allow the user to insert an exterior shell if necessary. This needed bat must allow the user to change the components of the bat to use varying materials, weights, sizes, and grip. This needed bat must provide barrels capable of use in connection with different governing bodies having different standards. This needed bat must be capable of use in connection with different bats for different purposes such as batting practice and game situations. This bat is presently lacking in the prior art.

Bat with interchangeable handle and barrel


An apparatus for sealing non-regular holes in a perforation in a wall, including a sealing member configured to be forcibly pressed into an inner surface of the perforation, an expandable member for forcing the sealing member against the inner surface of the perforation, and an expander member for causing the expandable member to force the sealing member against the inner surface of the perforation.

1. Field of the Invention
The present invention relates to plugs for the sealing of holes, in particular loosely toleranced holes, such as the perforations produced through the wall(s) of oilfield hole casings to sample reservoir fluid and to measure formation pressures.
2. The Prior Art
It is common, in oilfields, for the hole casings to be perforated, through the side of the casing, for purposes of sampling the fluid in the oilfield reservoir, and for determining the pressure in the oilfield formation. Once the sample has been taken, in order to restore the casing to utility for drilling or pumping purposes, the perforations must be closed. While efforts may be made to produce uniform perforations, so that they may be more easily closed, typically, the perforation will have a non-uniform circumferential contour, or the circumferential edge of the perforation may otherwise be rough.
Prior art apparatus for plugging such perforations are illustrated in Roe, U.S. Pat. No. 2,262,117; Mott, U.S. Pat. No. 4,007,905; Payton, U.S. Pat. No. 4,424,865; Geeting, U.S. Pat. No. 4,942,923; and Dave, U.S. Pat. No. 5,195,588.
It would be desirable to provide an apparatus and method for plugging such hole casings which would be capable of accommodating non-uniform or roughened perforations.

Plug apparatus suitable for sealing holes of variable or roughened diameter


The present disclosure provides a method of electronically exchanging tickets for an event in a secondary market from ticket sellers to ticket buyers located at remote terminals. The method comprises associating the tickets with authentication data of the ticket seller, receiving from ticket sellers electronic asks comprising an ask quantity and an ask price, receiving from a ticket buyer an electronic bid comprising a bid quantity and a bid price, comparing the bid to the asks, completing a transfer of the tickets when the bid price equals the ask price and the ask quantity is equal to or greater than the bid quantity, and reassociating the tickets with authentication data of the ticket buyer. Also disclosed is a system for performing the method.

The present invention relates to a system and method for real-time sales and distribution of tickets.
Paper tickets are widely used to grant access to patrons to sporting and general entertainment events. The ticket is a contract which grants the holder the right to attend the event and, normally, to sit in a particular seat. By transferring possession of the physical ticket, a ticketholder has transferred the right to attend the event.
However, many problems are associated with the transfer of paper tickets. In order to issue the ticket, the event promoter must organize the delivery of thousands of tickets. Additionally, if a purchaser wishes to transfer the ticket to a subsequent purchaser, the buyer and seller must be geographically proximate to physically transfer the ticket. With the advent of the Internet, buyers and seller have been able to locate each other in order to transfer tickets. However, the paper ticket still stands as an impediment to the efficient transfer of the right to attend an event because the seller must ship the ticket to the seller. By shipping the ticket the buyer and seller incur additional costs and require a greater lead time to allow the transfer to occur before the event. Each party must also have enough trust that the other party will deliver as agreed. Frequently, because of the impediments of sale, tickets are not widely transferred by geographically remote buyers and sellers.
Another type of impediment stands in the way of the efficient transfer of tickets. Most states have laws which prevent the sale of tickets for more than the face value of the ticket unless the seller has the consent of the event sponsor. To sell the ticket above face value, it is impractical for an individual seller to attempt to obtain permission from an event sponsor prior to selling a ticket. Because an event sponsor makes no money on the transaction, it has very little incentive to grant consent.
In a few other states laws allow a ticket broker to sell tickets at a price above the face value of the ticket, but not buy tickets above face value. Therefore, ticket brokers must obtain a ticket at the face value from the event sponsor and resell the ticket at a higher price. The ticket broker is violating the law if he purchases the ticket at a higher value from someone who is not a ticket broker. Finally, the ticker broker must still physically transfer the ticket to the buyer.
The present invention is a system and method which provides a legal, efficient way to transfer the right to attend an event at the market value of that right and to determine the market value. The present invention eliminates the disadvantages of the prior art.
The present disclosure provides a method of electronically exchanging tickets for an event in a secondary market from ticket sellers to ticket buyers located at remote terminals. The method comprises associating the tickets with authentication data of the ticket seller, receiving from ticket sellers electronic asks comprising an ask quantity and an ask price, receiving from a ticket buyer an electronic bid comprising a bid quantity and a bid price, comparing the bid to the asks, completing a transfer of the tickets when the bid price equals the ask price and the ask quantity is equal to or greater than the bid quantity, and reassociating the tickets with authentication data of the ticket buyer. Also disclosed is a system for performing the method.


An image sensor in accordance with exemplary embodiments of the inventive concept may include a pixel sensor array which includes an active pixel sensor and an optical black pixel sensor; a first analog to digital converter configured to convert a first sensing signal, which is provided from the active pixel sensor, to a first digital signal; a second analog to digital converter configured to convert a second sensing signal, which is provided from the optical black pixel sensor, to a second digital signal; and an output buffer configured to temporarily store and output the first digital signal and the second digital signal, wherein a plurality of noise characteristics of the second analog to digital converter is different from a plurality of noise characteristics of the first analog to digital converter.

Exemplary embodiments relate to semiconductor devices. In particular, exemplary embodiments relate to an image sensor which includes a heterogeneous analog to digital converter.
A mobile device, such as a smart phone, a tablet PC, a digital camera, a MP3 player, an e-book, etc., is being used more frequently. Most mobile devices are loaded with at least one image sensor to shoot an image. Examples of the at least one image sensor includes a charge coupled device (CCD) and a complementary metal-oxide semiconductor (CMOS) image sensor.
A CCD image sensor has low noise and superior image quality in comparison to a CMOS image sensor. However, a CMOS image sensor has a simple driving type, and can be embodied by various scanning methods. Since a CMOS image sensor can integrate a signal processing circuit in a single chip, the CMOS image sensor can be easily miniaturized. Further, since a CMOS image sensor can use a CMOS process technology, the unit production cost is low. A CMOS image sensor also has very low power consumption and can be easily applied to a mobile device.
A CMOS image sensor includes an analog to digital converter for converting an image signal being sensed by an analog signal to a digital signal. A pixel array of a CMOS image sensor includes a plurality of pixels arranged in a two-dimensional matrix form. Each of the plurality of pixels outputs an image signal from light energy. Each of the plurality of pixels accumulates photocharges corresponding to the amount of light supplied through a photodiode, and outputs a pixel signal of an analog current form according to the accumulated photocharges. The pixel signal is converted into a digital signal by an analog to digital converter (ADC). Thus, a number of ADC circuits which correspond to the number of column lines of the pixel array are needed.
Various noise filtering technologies are being used in a CMOS image sensor to generate a high quality image signal. Among various kinds of noise, horizontal noise (HN) has a characteristic which is easily sensed by the human eye. Thus, various studies for reducing horizontal noise HN are under way. Horizontal noise HN can be processed in the process of converting an analog signal being output from a pixel array of a CMOS image sensor into a digital signal. However, it is difficult to effectively remove horizontal noise HN due to random noise.

Image sensor including heterogeneous analog to digital convertor with different noise characteristics


Pyrazole compounds substituted with heteroaryl or pharmaceutically acceptable salts thereof that have an SGLT1 inhibitory activity and are useful for a drug, pharmaceutical compositions comprising the same, and pharmaceutical use thereof are disclosed. Specifically, a compound of Formula [X]:

SGLT1, i.e., Sodium-Glucose Cotransporter 1, is known to contribute to a great portion of absorption of glucose and galactose in the small intestine. It is reported that human SGLT1-deficient patients cause glucose-galactose malabsorption. Furthermore, it is confirmed that the expression of SGLT1 in the small intestine increases in diabetic patients and it is thought that increased sugar absorption in diabetic patients is caused by the high expression of SGLT1 in the small intestine.
Based on the knowledge, an SGLT1 inhibitor is expected to normalize the blood glucose level by blocking glucose absorption in the small intestine. An SGLT1 inhibitor is, therefore, considered to be effective against diabetes and diabetic complications associated with hyperglycemia. It is also considered to be effective against obesity by inhibiting the inflow of glucose into the body (Non Patent Literatures 1 and 2).
Voglibose, a generic name, is a drug approved for manufacturing and marketing under the Japan Pharmaceutical Affairs Act Article 14 (Approval number: 21600AMZ00368). Voglibose improves excess blood glucose after eating by inhibiting disaccharidase, α-glucosidase, that degrades disaccharides existing in the intestinal mucosa into monosaccharides and inhibiting or delaying the digestion and absorption of carbohydrate in the intestinal tract. Such a pharmacological effect is known to be effective against delayed onset of type 2 diabetes in imparied glucose tolerance.
Based on the knowledge, inhibition of sugar absorption through small intestine with an SGLT1 inhibitor and thereby improvement of excess blood glucose after eating is thought to be effective against delayed onset of type 2 diabetes in imparied glucose tolerance.
The expression of SGLT1 is confirmed in cardiac muscle cells. It is known that GLUT1 (Glucose Transporter Type 1) and GLUT4 (Glucose Transporter Type 4) usually have a role in uptake of glucose into cardiac muscle cells and the contribution of SGLT1 is reduced. The expression of SGLT1 is, however, induced in the cardiac muscle of mice into which is introduced mutated genes of PRKAG2 (gamma 2 subunit of AMPK (AMP-Activated Protein Kinase)) which is a responsible gene of familial hypertrophic cardiomyopathy (glycogen accumulation-type myocardosis), or mice which undergo myocardial ischemia treatment, and SGLT1 is reported to contribute to the uptake of glucose to cardiac muscle cells in these pathologies. Glucose incorporated by SGLT1 is thought to be excessively accumulated or metabolized within cardiac muscle cells and impair the cells. It is reported in the former mouse model that accumulation of glycogen in the cardiac muscle is actually inhibited by the treatment of a non-selective SGLT inhibitor, phlorizin.
Based on the knowledge, an SGLT1 inhibitor is thought to be effective against hypertrophic cardiomyopathy and ischemic heart disease by inhibiting uptake of excess glucose into cardiac muscle cells (Non Patent Literatures 3 and 4).
SGLT1 is stabilized in cancer cells by epidermal growth factor receptors, i.e., surface proteins on many kinds of cancer cells. It is known that transporters of glucose, lactic acid, and amino acid, etc. are involved in nutrition supply to cancer cells, and especially, regarding the transportation of glucose, SGLT1 and GLUT1 continuously supply glucose to cancer cells. When glucose is not supplied over a long period of time, cells are destroyed by autophagy.
Based on the knowledge, an SGLT1 inhibitor is thought to inhibit supply of glucose to cancer cells and show anticancer activity (Non Patent Literatures 5 and 6).
Since carbohydrate is degraded to monosaccharides in the gastrointestinal tract in diet and is absorbed in the upper gastrointestinal tract, many sugars never reach the lower gastrointestinal tract. When, however, drugs that delay or inhibit glucose absorption are administered, or a large amount of resistant polysaccharides are ingested, then undigested sugars are retained in the lower gastrointestinal tract and the undigested sugars retained in the lower gastrointestinal tract cause osmotic diarrhea.
An SGLT1 inhibitor inhibits the glucose absorption and increases the amount of monosaccharides in the lower gastrointestinal tract. The SGLT1 inhibitor is, therefore, believed to be effective against constipation.

Pyrazole compounds substituted with heteroaryl and pharmaceutical use thereof

Abstract: wherein R1 is hydrogen or halogen, R2 is C1-6 alkyl or halo-C1-6 alkyl, Ring Het is substituted pyridyl or optionally substituted pyrazinyl, pyrimidinyl, or pyridazinyl, or a pharmaceutically acceptable salt thereof, a pharmaceutical composition comprising it, and pharmaceutical use thereof is provided.


The present invention is directed to a process for preparing NES-type zeolites using novel nitrogen-based structure directing agents. The structure directing agents used in preparing NES-type zeolites selected from the group consisting of 1,4-bis(N,N-dimethylcyclohexylammonium) butane dications and 1,5-bis(N,N-dimethylcyclohexylammonium) pentane dications.

Zeolites having the NES framework topology defined by the connectivity of the tetrahedral atoms are known. See, for example, Ch. Baerlocher et al., Atlas of Zeolite Framework Types, 6th Revised Edition, 2007 of the International Zeolite Association. An example of an NES-type zeolite includes the zeolite designated "Nu-87." U.S. Pat. Nos. 5,041,402; 5,102,641; 5,178,748 and 5,345,021, all to Casci et al., disclose Nu-87.
It has now been found that NES-type zeolites can be prepared using 1,4-bis(N,N-dimethylcyclohexylammonium)butane dications and 1,5-bis(N,N-dimethylcyclohexylammonium)pentane dications as SDAs.

This patent is subject to a terminal disclaimer.

Method for preparing NES-type zeolites using novel structure directing agents


An apparatus and method for setting the upstand height of the studs of an array of studs used to form antenna panels is disclosed. The apparatus includes a transducer beam having a row of spaced-apart distance transducers. The apparatus also includes an actuator beam having a row of spaced rotary actuators. The actuators rotate the threaded studs to raise or lower the studs until the corresponding transducer indicates that the stud has achieved an intended height. Also disclosed is a method using an array of laser diodes, rather than the transducer beam, arranged at one end of the base plate and an array of photo diodes at the opposite end. The output of the diodes indicates the height of the studs.

The prior procedure and apparatus used to create such antenna panels is described in the paper "The Australia Telescope Antennas: Development of High-Accuracy Low-Cost Surface Panels" by B F Parsons and D E Yabsley published in October 1985 in the Proceedings of the IREE of Australia (conference (IREECON 85) pp 716-719). A similar arrangement is disclosed in U.S. Pat. No. 4,731,144 issued Mar. 15, 1988 to Kommineni et al. Both these documents disclose arrangements in which the stud height of each stud is adjusted by manually turning the bolt which forms the stud. This manual adjustment is a very time consuming, and therefore and expensive, procedure.

Method and apparatus of stud array upstand setting

Commonwealth Scientific and Industrial Research Organisation


A gadolinium (3.sup.+) complex of polyamine polyacetate, comprising a polyamine nucleus having a pendant boron-containing substituent on one of the nitrogen or carbon atoms of the polyamine nucleus. The boron-gadolinium compound may suitably be of the formula: ##STR1## wherein: is a polyamine coordination structure capable of covalently bonding the substitutents R.sub.1, R.sub.2, R.sub.3 and R.sub.4 and of complexing with Gd;. R.sub.1, R.sub.2, and R.sub.3 are independently selected from carboxyl, carboxylic salt groups, carboxylic ester groups, and carboxylate anion; PA0 R.sub.4 is a boron-containing group; and PA0 x is a number from zero to 4.. Also disclosed is a method of treating a tumor-bearing mammalian subject by boron neutron capture therapy wherein the boron drug employed in such treatment comprises a boron-gadolinium compound, and a method of conducting sequential imaging and NCT treatment of a tumor tissue site in the corporeal structure of a mammalian subject, comprising administering to the mammalian subject an MRI imagingly- and NCT treatingly-effective amount of an effective boron-gadolinium compound, visualizing the tumor tissue site by MRI, and treating the tumor tissue by NCT.

1. Field of the Invention
This invention relates to novel boron-gadolinium compounds, and to a method of conducting imaging processes and/or neutron capture therapy with boron-gadolinium compounds.
2. Description of the Related Art
Interest in the Neutron Capture Therapy (NCT) of cancer has increased tremendously in recent years. A number of compounds are already in preclinical or clinical trials in the U.S., Europe, Japan, and Australian. Most of these studies are based on the use of .sup.10 B as the neutron capture agent. Although .sup.10 B has certain advantages (e.g., versatile chemistry, cost-effectiveness, type of radiation generated upon neutron capture, etc.) over other potential neutron capture agents, there are also some problems. For example, the boron concentrations in tissues are difficult to measure and noninvasive determination of boron distribution in the body is very difficult. Additionally, boron compounds in general have given poor tumor to blood ratio in the past, with some notable exceptions.
Recently, reports have described the use of .sup.157 Gd compounds as neutron capture agents. Gadolinium-157 has a much larger cross-section for thermal neutrons than boron-10 (66 times larger), and some Gd complexes have been shown to give good tumor to blood and tumor to tissue ratios.
A significant property of .sup.157 Gd is that, being paramagnetic, it is a very good contrast agent for imaging by magnetic resonance. In fact, one Gd complex is already in clinical use as an MRI agent.
However, as in the case with boron-10, gadolinium-157 also has certain disadvantages as a neutron capture agent. The gadolinium complexes are less potent and can be more toxic due to the type of radiation (.gamma.-radiation) generated upon neutron capture.
Therefore, a combination of .sup.10 B and .sup.157 Gd might compensate each isotope's weaknesses and offer a better therapeutic method of treatment. A single agent incorporating both .sup.10 B and .sup.157 Gd may therefore provide not only the diagnostic capability of detecting the tumor, but at the same time a better means of destroying the tumor by both .sup.10 B-NCT and .sup.157 Gd-NCT.
NCT is based on the nuclear reaction produced when a neutron capture agent such as .sup.10 B or .sup.157 Gd isotope (localized in tumor tissues) is irradiated with low energy thermal neutrons. The radiation produced is capable of effecting selective destruction of tumor cells while sparing normal cells. The advantage of NCT is the fact that it is a binary system, capable of independent variation of control of the neutron capture agent and thermal neutrons.
While a number of nuclei have high cross section for thermal neutrons, most of the studies have been focused on the use of .sup.10 B as the neutron capture agent. It would therefore be an advance in the art, and is an object of this invention to provide NCT agents with both .sup.10 B and .sup.157 Gd in the same compound.
Boron-10 has a high cross-section (3838 barns) for thermal neutrons. The reaction products of .sup.10 B and thermal neutrons have short path length and the high linear energy transfer (LET) radiation (LET>100 KeV/.mu.m) is deposited within the cell giving preferential destruction if the boron is localized in the tumor.
Another advantage of .sup.10 B is that the chemistry of boron is very versatile and a variety of boron compounds can be readily synthesized. However, the problems with boron compounds are: 1) most of the compounds studied so far give poor tumor to blood ratio, although there are notable exceptions, e.g., boronated porphyrins; 2) boron distribution in the body is difficult to determine without isolating the organs and tissue, and although .sup.11 B nmr has been used for imaging, it is not very sensitive; and 3) boron concentrations in the tumor are also difficult to determine.
Gadolinium-157 has a much larger cross section (66 times larger than .sup.10 B) for thermal neutrons than boron-10. Gadolinium compounds (due to the presence of unpaired electrons) have been used successfully for NMR imaging and the diethylenetriamine pentaacetic acid complex of Gd.sup.3+ is currently undergoing clinical trials as an imaging agent. Gd compounds have been shown to provide high tumor concentrations and good tumor to tissue and tumor to blood ratios.
Many Gd complexes behave similar to the corresponding technetium complexes. Therefore, by substituting .sup.99m Tc for Gd along with the Gd complex, and by determining the concentration of technetium in various tissues, the concentration of Gd can be estimated. Alternatively, Gd concentrations in various tissues may be determined indirectly by measuring proton relaxivities (MRI).
The disadvantages of Gd are, however, that the major cell killing component of the radiation produced from Gd.sup.157 and neutron reaction is Auger electrons. To be effective these Auger e's have to be released in the vicinity of the genetic material and this constraint limits the effectiveness of Gd NCT in comparison to .sup.10 B-NCT. A second drawback of the .sup.157 Gd NCT is that a second component of radiation from .sup.157 Gd-neutron reaction, low LET gamma rays, are not only less effective in killing cells but can also travel longer distances and can destroy normal tissue. On the other hand, delivery of radiation to the surrounding tissue may increase the chance of hitting all the cells in the tumor. Thus a combination of boron-10 and gadolinium-157 may require lower concentration of each component (and decrease side effects) and still be more effective than each individual component at a higher concentration.
Concerning desirable characteristics for imaging reagents generally, the basic properties of good magnetic resonance imaging agents are as follows:
1) Relaxivity: The relaxivity of metal complexes (efficiency with which a complex enhances proton relaxation rate of water) should be sufficiently high. However, an increase of as little as 10-20% in 1/T.sub.1 could be detected by NMR imaging. Relaxivity may be increased by providing one or more inner sphere coordination site(s) for water molecules. PA1 2) Specificity: For NMR imaging agents it is important that the agent enhances the relaxation rates of target tissue in preference to other tissues. This may be accomplished either by preferential incorporation of compound or by difference in relaxivity if the complex has a higher relaxivity in the environment of one tissue over others. PA1 3) in vivo stability, lack of toxicity and rapid excretability: It is extremely important that the imaging agent has a low acute and chronic toxicity. Many complexes, while inherently nontoxic, could exhibit high toxicity upon dissociation into the free metal ions and ligands. Therefore, both the thermodynamic and the kinetic stabilities of complexes are very important. Additionally, after serving their purpose, diagnostic agents should be excreted within hours of administration. Of course, retention in tumor is highly desirable for NCT. PA1 4) Solubility in water: For ease of delivery, the imaging agent should have good solubility in water. PA1 5) Osmolality: Although not essential, it is beneficial to have uncharged species to prevent hyperosmolality with respect to body fluids. PA1 1) High cross-section for thermal neutrons: As indicated earlier, both .sup.10 B and .sup.157 Gd have high cross-section for thermal neutrons. PA1 2) Tumor specificity: In order for NCT to be effective, the neutron capture agent should preferentially localize into tumor cells. The position inside the cell is also important. So far, this has been one of the most challenging problems for NCT. PA1 3) Stability, Excretability and lack of toxicity: The same criteria apply here as for imaging agents. Not only should the compound have good stability and low toxicity after the treatment (or even before neutron capture reaction), the compound should also be readily excreted from the normal tissue of the body, but retained in tumor cells. PA1 R.sub.1, R.sub.2, and R.sub.3 are independently selected from carboxyl, carboxylic salt groups, carboxylic ester groups, and carboxylate anion; PA1 R.sub.4 is a boron-containing group; and PA1 x is a number from zero to 4. PA1 R.sub.4 is a boron-containing group; and PA1 x is a number from zero to 4. PA1 1,4,7-tris (carboxymethyl)-10-(1-carboranylpropyl)-1,4,7,10-tetraazacyclododecane PA1 1,4,7-tris (carboxymethyl)-10-(1-phenylpropyl)-1,4,7,10-tetraazacyclododecane PA1 R.sub.1, R.sub.2, and R.sub.3 are independently selected from carboxyl, carboxylic salt groups, carboxylic ester groups, and carboxylate anion; PA1 R.sub.4 is a boron-containing group; and PA1 x is a number from zero to 4. PA1 R.sub.1, R.sub.2, and R.sub.3 are independently selected from carboxyl, carboxylic salt groups, carboxylic ester groups, and carboxylate anion; PA1 R.sub.4 is a boron-containing group; and PA1 x is a number from zero to 4. PA1 R.sub.4 is a boron-containing group; and PA1 x is a number from zero to 4.
Considering the desired properties of NCT reagent materials, the properties of good NCT agents are as follows:
In addition, the criteria of good water solubility and low osomality also apply to NCT agents.
Accordingly, it is one object of the present invention to provide novel boron-gadolinium compounds having utility for imaging applications such as MRI as well as for NCT.
It is another object of the invention to provide a method of making such boron-gadolinium compounds.
It is a further object of the invention to provide a method of and compounds for contemporaneously conducting imaging and NCT processes, utilizing a single reagent formulation.
Other objects and intents of the present invention will be more fully apparent from the ensuing disclosure and appended claims.

Boron-gadolinium compounds and method of conducting imaging and/or neutron capture therapy with same


A method and apparatus for measuring properties of a fluid composition in a conduit includes a mechanical resonator connected to a measurement circuit. The measurement circuit provides a variable frequency input signal to the mechanical resonator, causing the mechanical resonator to oscillate. The input signal is then sent to the mechanical resonator and swept over a selected frequency range. The mechanical resonator""s response over the frequency range depends on various characteristics of the fluid being tested, such as the temperature, viscosity, and other physical properties.

The present invention is directed to using mechanical oscillators for measuring various properties of fluids (including both liquids and vapors), and more particularly to a method and system using a mechanical oscillator (resonator) for measuring physical, electrical and/or chemical properties of a fluid based on the resonator""s response in the fluid to a variable frequency input signal.
Companies are turning to combinatorial chemistry techniques for developing new compounds having novel physical and chemical properties. Combinatorial chemistry involves creating a large number of chemical compounds by reacting a known set of starting chemicals in all possible combinations and then analyzing the properties of each compound systematically to locate compounds having specific desired properties. See, for example, U.S. patent application Ser. No. 08/327,513 (published as WO 96/11878), filed Oct. 18, 1994, entitled xe2x80x9cThe Combinatorial Synthesis of Novel Materialsxe2x80x9d, the disclosure of which is incorporated by reference.
The virtually endless number of possible compounds that can be created from the Periodic Table of Elements requires a systematic approach to the synthesizing and screening processes. Thus, any system that can analyze each compound""s properties quickly and accurately is highly desirable. Further, such a system would be useful in any application requiring quick, accurate measurement of a liquid""s properties, such as in-line measurement of additive concentrations in gasoline flowing through a conduit or detection of environmentally-offending molecules, such as hydrogen sulfide, flowing through a smokestack.
It is therefore an object of the invention to measure simultaneously both the physical and the electrical properties of a fluid composition using a mechanical resonator device.
It is also an object of the invention to detect differences clearly between two or more compounds in a fluid composition by using a mechanical resonator device to measure a composition""s physical and electrical properties.
It is a further object of the invention to use a mechanical resonator device to monitor and measure a physical or chemical transformation of a fluid composition.
It is also an object of the invention to use a mechanical resonator device to detect the presence of a specific material in a fluid.
The present invention includes a method for measuring a property of a fluid composition using a tuning fork resonator, the method comprising:
placing the tuning fork resonator in the fluid composition such that at least a portion of the tuning fork resonator is submerged in the fluid composition;
applying a variable frequency input signal to a measurement circuit coupled with the tuning fork resonator to oscillate the tuning fork resonator;
varying the frequency of the variable frequency input signal over a predetermined frequency range to obtain a frequency-dependent resonator response of the tuning fork resonator; and
determining the property of the fluid composition based on the resonator response.
The method can also measure a plurality of fluid compositions, wherein the fluid compositions are liquid compositions, using a plurality of tuning fork resonators, wherein the method further comprises:
providing an array of sample wells;
placing each of said plurality of liquid compositions in a separate sample well;
placing at least one of said plurality of tuning fork resonators in at least one sample well;
applying a variable frequency input signal to a measurement circuit coupled with each tuning fork resonator in said at least one sample wells to oscillate each tuning fork resonator associated with each of said at least one sample well;
varying the frequency of the variable frequency input signal over a predetermined frequency range to obtain a frequency-dependent resonator response of each tuning fork resonator associated with said at least one sample well; and
analyzing the resonator response of each tuning fork resonator associated with said at least one sample well to measure a property of each liquid composition in said at least one sample well.
Accordingly, the present invention is directed primarily to a method using a mechanical piezoelectric quartz resonator (xe2x80x9cmechanical resonatorxe2x80x9d) for measuring physical and electrical properties, such as the viscosity density product, the dielectric constant, and the conductivity of sample liquid compositions in a combinatorial chemistry process. The detailed description below focuses primarily on thickness shear mode (xe2x80x9cTSMxe2x80x9d) resonators and tuning fork resonators, but other types of resonators can be used, such as tridents, cantilevers, torsion bars, bimorphs, or membrane resonators. Both the TSM resonator and the tuning fork resonator can be used to measure a plurality of compounds in a liquid composition, but the tuning fork resonator has desirable properties that make it more versatile than the TSM resonator.
The mechanical resonator is connected to a measuring circuit that sends a variable frequency input signal, such as a sinusoidal wave, that sweeps over a predetermined frequency range, preferably in the 25-30 kHz range for the tuning fork resonator and in a higher range for the TSM resonator. The resonator response over the frequency range is then monitored to determine selected physical and electrical properties of the liquid being tested. Although both the TSM resonator and the tuning fork resonator can be used to test physical and electrical properties, the tuning fork resonator is an improvement over the TSM resonator because of the tuning fork""s unique response characteristics and high sensitivity.
Both the TSM resonator and the tuning fork resonator can be used in combinatorial chemistry applications according to the present invention. The small size and quick response of the tuning fork resonator in particular makes it especially suitable for use in combinatorial chemistry applications, where the properties of a vast number of chemicals must be analyzed and screened in a short time period. In a preferred embodiment, a plurality of sample wells containing a plurality of liquid compositions are disposed on an array. A plurality of TSM or tuning fork resonators are dipped into the liquid compositions, preferably one resonator per composition, and then oscillated via the measuring circuit. Because the resonating characteristics of both the TSM resonator and the tuning fork resonator virtually eliminate the generation of acoustic waves, the size of the sample wells can be kept small without the concern of acoustic waves reflecting from the walls of the sample wells. In practice, the tuning forks can be oscillated at a lower frequency range than TSM resonators, making the tuning forks more applicable to real-world applications and more suitable for testing a wide variety of compositions, including high molecular weight liquids.
In another embodiment of the invention, the mechanical resonator is coated with a material to change the resonator""s characteristics. The material can be a general coating to protect the resonator from corrosion or other problems affecting the resonator""s performance, or it can be a specialized xe2x80x9cfunctionalizationxe2x80x9dcoating that changes the resonator""s response if a selected substance is present in the composition being tested by the resonator.
To obtain a more complete range of characteristics for a selected fluid composition, multiple resonators having different resonator characteristics can be connected together as a single sensor for measuring the fluid composition. The resonator responses from all of the resonators in the sensor can then be correlated to obtain additional information about the composition being tested. By using resonators having different characteristics, the fluid composition can be tested over a wider frequency range than a single resonator. Alternatively, a single resonator that can be operated in multiple mechanical modes (e.g. shear mode, torsion mode, etc.) can be used instead of the multiple resonators. The resonator responses corresponding to each mode would be correlated to obtain the additional information about the composition.
The mechanical resonator system of the present invention, particularly a system using the tuning fork resonator, can also be used to monitor changes in a particular liquid by keeping the resonator in the liquid composition as it undergoes a physical and/or chemical change, such as a polymerization reaction. The invention is not limited to measuring liquids, however; the quick response of the tuning fork resonator makes it suitable for measuring the composition of fluid compositions, both liquid and vaporous, that are flowing through a conduit to monitor the composition of the fluid.

Method and apparatus for characterizing materials by using a mechanical resonator