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Copyright of Bearing is the property of Bearing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A small sheet-type LFM is proposed to solve the problems of leakage and deformation in the design of traditional sheet-type LFM. The pressure tap is set in the middle of the laminar flow channel to extract pressure from the fully developed laminar flow. The design value Remax·de/l is 5.81, which is much higher than the 2~2.5 required by the traditional design. Experimental results show that the linearity factor ξL of small sheet-type LFM can reach 0.81% and the accuracy is up to 1%, which shows that the present design can effectively overcome the nonlinear effects caused by sudden expansion and contraction. In addition, when the flow rate is above 20% designed maximum valve, the calculation error of pressure drop can be controlled below 5.42%.

In order to enhance the performances of clock and data recovery circuit(CDR) in the high speed multichannel serial transceiver system, a novel phase interpolator(PI) circuit used in CDR has been proposed in the paper. It adopts four groups of differential signal and DAC to act on common load resistance, generates complementary thermometer code through digital filter to control DAC output current, realizes phase weight allocation for differential input clock to make 128 times interpolated, and optimizes the differential signal by input stage four phase correction circuit and duty cycle adjustment circuit. This chip is fabricated in 40 nm CMOS process, the simulation results show that PI has good linearity from 1 GHz to 6 GHz, and DNL is no more than 1.4 LSB, INL is no more than 1.5 LSB, and has been successfully applied to a variety of high speed SerDes.

Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rotary variable differential transformer（RVDT）adopts non-contract design, has the advantages of high sensitivity, good linearity and compact structure, and is widely used in automatic control system in the aviation field. The air gap between stator and rotor is one of the important structural parameters to improve its performance and reliability. This paper studies the air gap between stator and rotor and develops an optimized design with a typical product. Through theoretical simulation analysis and physical experimental tests, the influence of the air gap on the linearity and gradient of RVDT, the two important static indicators, is studied. In this way, under a certain structure size, the influence of the air gap size on the RVDT output gradient and linearity and the reasonable selection range of the air gap are obtained. The proposed study can not only provide strong support for the selection of product structure design parameters, but also revise the actual product structure size during engineering realization to improve the product qualification rate. In addition, the relevant research methods and conclusions obtained can also be promoted and applied to the development of redundant RVDT, providing a reference for the rapid development of such products. [ABSTRACT FROM AUTHOR]

Due to the low measurement precision, small measurement range and low stability of traditional displacement sensors, this paper propose and implement a displacement sensor based on varied line-space grating, with the displacement characteristic test and the error problems in the measurement process are accomplished and analyzed, respectively. In the experiment, the varied line-space grating is placed on the electric displacement platform. The incident position of the light spot is controlled by adjusting the displacement of the platform. Besides, the correlation between the grating displacement and the wavelength of the reflection spectrum first-order diffraction center is established to realize the wavelength coding of the displacement. The platform movement range is 0~20 mm, with step length of 2 mm, and the round trip repeated measurement is made for 6 times. The central wavelength at each shift point is recorded and the displacement characteristics of the sensor are calibrated. Based on the error analysis of the central wavelength data generated by repeated measurements at each shift point, the standard deviation of multiple measurements at each point is analyzed by using Bessel formula combined with the Pieters method. The reliability of the data is further determined by combining with the 3σ criteria. The experimental results show that the sensor system has no systematic error and gross error. Also, the wavelength and displacement of the sensor change linearly, and the linearity of multiple repetitions is better than 0.994 6. The average displacement sensitivity of the sensor's full range is 16.67 nm/mm. The content of this paper can provide a certain research reference for displacement sensing system based on varied line-space grating.

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of problems of traditional current detection method which took electromagnetic current transformer as the core that it was difficult to install and maintain, took up a lot of space and has low precision, a current detection system of underground intelligent substation with Rogowski coil as sensing head was designed. Design of integral reduction circuit and adaptive amplifier circuit was introduced, and the system stability analysis as well as Rogowski coil test, linearity test, frequency characteristic test and temperature characteristic test were carried out. Test results show that the system has high precision and good linearity.

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the influence of various static performance parameters of line structured light sensors on its measurement accuracy, a plan of line structured light sensors static performance test scheme was designed. A second level gauge block, nano-positioning table and laser interferometer were used on high-precision mobile platform. The important static performance parameters ,such as stability, repeatability and linearity, were analyzed to quantify the influence of various static performance parameters on the measurement accuracy of the sensor. The working surface of the second level gauge block was used as the measurement surface during the test. The high-precision mobile platform was used to test the whole measurement area of the sensor. The laser interferometer was used to compensate the positioning error of the mobile platform, which improved the reliability of the measurement result. The research results indicate that the sensor needs 1 hour to ensure the measurement accuracy, and the repeatability of the middle measurement area is the best with an average value of 0.418 μm. The linearity of the sensor has the greatest influence on the measurement accuracy. The error caused by the sensor nonlinearity is at most 11.2 μm. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Physical Education Institute / Shanghai Tiyu Xueyuan Xuebao is the property of Shanghai Physical Education Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The linearity index was proposed for evaluating piezoelectric ceramic excitation signal， and experiment was carried out to study a PZT ceramics based on self-designed piezoceramic excitation feedback system. After analyzing the influence factors and law of excitation force， an evaluation method of single-frequency excitation capability was proposed. Evaluation equation was established based on the experimental data， and confidence interval in frequency domain of single-frequency excitation was obtained to make good use of piezoelectric ceramic exciter during the high order vibration test of thin-walled structures. The overall characteristics of the piezoelectric ceramic single-frequency excitation showed that high level excitation capability can be realized under the smaller single-frequency condition， while the low level excitation capability can only be realized under the larger single-frequency condition. [ABSTRACT FROM AUTHOR]

In order to solve the problem of the standard facilities with high expanded uncertainty which affected by the linearity of the standard flowmeter itself, the improvement of flow meter accuracy by compressing measurement range was investigated after the analysis of the effect of the accuracy of vortex flowmeter, the relationship between the linearity of the standard flowmeters and the expanded uncertainty of the standard facilities was established. A method was presented to reduce the expanded uncertainty of the standard facilities. The expanded uncertainty of the standard facilities were evaluated on the theoretical calculation, the efficacy were tested. The experimental results show that we can reduce the expanded uncertainty of the standard facilities by compressing measurement range and combination optimization. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A balanced vibration of driving module excited by electrostatic driving signal is the working base for MEMS gyroscope. In order to analyze the linearity of the vibration system, a method based on computer vision is applied to detect the vibration process, which works with the help of high-speed vidicon to acquire the video images of vibration displacement of gyroscope driving module, under the AM (amplitude modulation) driving voltage signal with inherent frequency. By means of image processing, target identifying and motion parameter extracting from the video images, the vibration of the gyroscope with time variation could be obtained. Finally, linearity of the vibration system could be analyzed by focusing on the displacement of vibration responding to the amplitude of driving voltage signal. [ABSTRACT FROM AUTHOR]

The distance mathematical modeling is the foundation of streak tube imaging lidar (STIL) system. Based on the STIL imaging principle and the experimental observation, the relation of target relative distance to the CCD image distance was theoretically analyzed. The analyzed result shows that the nonlinear relative deviation between target distance and image distance is very small. That means the target distance and CCD image distance present an approximately linear relationship, so the distance mathematical modeling could be processed linearly. A hardware platform was built and two crucial parameters of scanning velocity and position of static reference line were ascertained by measurement. Based on the above, the distance model for STIL system was built and its validity has been verified. [ABSTRACT FROM AUTHOR]

To overcome the shortage of common method of invariable feedback time, a scheme using improved invariable feedback time of the reference current is proposed to reduce the error of the voltage-to-frequency converter. With the same circuit resolution, the feedback time is increased by 1.8 times. The linearity accuracy of designed converter using new method can be better than 0.005 0% in the full scale of output frequency -- 200~200 kHz. [ABSTRACT FROM AUTHOR]

A new digitally self calibration algorithm was investigated to compensate interstage gain errors in pipeline analog digital converter (ADC). An improved pipeline ADC structure was introduced which is more adapted to the digital self calibration algorithm. Missing code and missing decision levels can be eliminated by adjusting reference voltage, and the effect of non linearity is apparently improved. [ABSTRACT FROM AUTHOR]