An accuracy optimization method for random access inter-satellite measurement system

2019 ◽  
Author(s):  
Xiaoyi Xu ◽  
Chunhui Wang ◽  
Zhonghe Jin ◽  
Bei Ye
Keyword(s):  
Measurement System ◽  
Random Access ◽  
Optimization Method ◽  
Satellite Measurement

Accuracy optimization method of ultrasonic power measurement system based on acousto-optic effect

2021 ◽  
Author(s):  
Ben Shen ◽  
Baoshan Zeng ◽  
Xiaojian Liu ◽  
Chenzefang Feng ◽  
Zhou Hu ◽  
...  
Keyword(s):  
Measurement System ◽  
Optimization Method ◽  
Power Measurement ◽  
Ultrasonic Power

scholarly journals Sensitive, Linear, Robust Current-To-Time Converter Circuit for Vehicle Automation Application

Electronics ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 490
Author(s):  
Nandakishor Yadav ◽  
Youngbae Kim ◽  
Mahmoud Alashi ◽  
Kyuwon Ken Choi
Keyword(s):  
Random Access ◽  
Optimization Method ◽  
Digital Converter ◽  
Large Area ◽  
Negative Bias Temperature Instability ◽  
Analog To Digital ◽  
Bias Temperature Instability ◽  
Linear Current ◽  
Converter Design ◽  
Vehicle Automation

Voltage-to-time and current-to-time converters have been used in many recent works as a voltage-to-digital converter for artificial intelligence applications. In general, most of the previous designs use the current-starved technique or a capacitor-based delay unit, which is non-linear, expensive, and requires a large area. In this paper, we propose a highly linear current-to-digital converter. An optimization method is also proposed to generate the optimal converter design containing the smallest number of PMOS and sensitive circuits such as a differential amplifier. This enabled our design to be more stable and robust toward negative bias temperature instability (NBTI) and process variation. The proposed converter circuit implements the point-wise conversion from current-to-time, and it can be used directly for a variety of applications, such as analog-to-digital converters (ADC), used in built-in computational random access (C-RAM) memory. The conversion gain of the proposed circuit is 3.86 ms/A, which is 52 times greater than the conversion gains of state-of-the-art designs. Further, various time-to-digital converter (TDC) circuits are reviewed for the proposed current-to-time converter, and we recommend one circuit for a complete ADC design.

Development of measurement system for radiation effects on synchronous dynamic random access memory

2013 ◽  
Vol 25 (10) ◽  
pp. 2699-2704
Author(s):  
姚志斌 Yao Zhibin ◽  
罗尹虹 Luo Yihong ◽  
陈伟 Chen Wei ◽  
何宝平 He Baoping ◽  
张凤祁 Zhang Fengqi ◽  
...  
Keyword(s):  
Measurement System ◽  
Radiation Effects ◽  
Random Access ◽  
Random Access Memory ◽  
Dynamic Random Access Memory ◽  
Access Memory

scholarly journals Circuit Optimization Method to Reduce Disturbances in Poly-Si 1T-DRAM

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1209
Author(s):  
Yejin Ha ◽  
Hyungsoon Shin ◽  
Wookyung Sun ◽  
Jisun Park
Keyword(s):  
Memory Performance ◽  
Random Access ◽  
Random Access Memory ◽  
Optimization Method ◽  
Memory Device ◽  
Circuit Optimization ◽  
Access Memory ◽  
Source Line ◽  
Bias Condition ◽  
Circuit Configuration

A capacitorless one-transistor dynamic random-access memory device (1T-DRAM) is proposed to resolve the scaling problem in conventional one-transistor one-capacitor random-access memory (1T-1C-DRAM). Most studies on 1T-DRAM focus on device-level operation to replace 1T-1C-DRAM. To utilize 1T-DRAM as a memory device, we must understand its circuit-level operation, in addition to its device-level operation. Therefore, we studied the memory performance depending on device location in an array circuit and the circuit configuration by using the 1T-DRAM structure reported in the literature. The simulation results show various disturbances and their effects on memory performance. These disturbances occurred because the voltages applied to each device during circuit operation are different. We analyzed the voltage that should be applied to each voltage line in the circuit to minimize device disturbance and determine the optimized bias condition and circuit structure to achieve a large sensing margin and realize operation as a memory device. The results indicate that the memory performance improves when the circuit has a source line and the bias conditions of the devices differ depending on the write data at the selected device cell. Therefore, the sensing margin of the 1T-DRAM used herein can expectedly be improved by applying the proposed source line (SL) structure.

scholarly journals A Combined Measurement Method for Large-Size Aerospace Components

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4843
Author(s):  
Zhilong Zhou ◽  
Wei Liu ◽  
Qiong Wu ◽  
Yuxin Wang ◽  
Binchao Yu ◽  
...  
Keyword(s):  
Measurement System ◽  
Measurement Method ◽  
Measurement Accuracy ◽  
Optimization Method ◽  
High Accuracy ◽  
Control Points ◽  
3D Scanner ◽  
Global Control ◽  
Accuracy Measurement ◽  
Large Size

Automated and high-accuracy three-dimensional (3D) shape measurement is required in quality control of large-size components for the aerospace industry. To eliminate the contradiction between global measurement and local precision measurement control in 3D digitalization for the key local features of the large-size components, a combined measurement method is proposed, including a 3D scanner, a laser tracker, and an industrial robot used as an orienting device, to achieve high-accuracy measurement. As for improving the overall measurement accuracy, an accurate calibration method based on coordinate optimization of common points (COCP) and coordinate optimization of global control points (COGP) is proposed to determine the coordinate systems. Firstly, a coordinate optimization method of common points (COCP) is recommended. Then, a coordinate optimization method of global control points (COGP) based on the angular constraint is proposed for minimizing the measurement errors and improving the measurement accuracy of the position and orientation of the 3D scanner. Finally, a combined measurement system is established, and validation experiments are carried out in laboratory within a distance of 4 m. The calibration experiment results demonstrate that the max and mean errors of the coordinate transformation have been reduced from 0.037 and 0.022 mm to 0.021 and 0.0122 mm. Additionally, the measurement experiment results also show that the combined measurement system features high accuracy.

The Nimbus F Random Access Measurement System (RAMS)

1975 ◽  
Vol 13 (1) ◽  
pp. 18-27 ◽  
Author(s):  
James Coates
Keyword(s):  
Measurement System ◽  
Random Access

scholarly journals Determining the likely localization of methane sources using forecast time series and satellite data

2021 ◽  
Author(s):  
M.V. Platonova ◽  
E.G. Klimova
Keyword(s):  
Observational Data ◽  
Mathematical Formulation ◽  
Three Dimensional ◽  
Measurement Data ◽  
Real Data ◽  
Optimization Method ◽  
Satellite Measurement ◽  
Time Interval ◽  
Methane Fluxes ◽  
Forecast Time

The paper is devoted to the topical problem of determining the sources of methane from observational data. An algorithm based on the statistical optimization method used to estimate a time constant parameter is considered. To implement the algorithm, a variant of ensemble smoothing is used, which is an optimal estimate of the desired parameter based on observational data and forecast for a given time interval. This paper presents the implementation of the algorithm for real observational and forecast data, the results of a three-dimensional transport and diffusion model are taken as a mathematical model, and satellite measurement data are used as observational data. Methane fluxes are estimated in subdomains of the Earth’s surface for specified time intervals. The paper contains a mathematical formulation of the problem, a scheme for its numerical implementation. The results of numerical experiments with model and real data are presented.

scholarly journals Calibration Method for Angular Positioning Deviation of a High-Precision Rotary Table Based on the Laser Tracer Multi-Station Measurement System

2019 ◽  
Vol 9 (16) ◽  
pp. 3417 ◽  
Author(s):  
Hongfang Chen ◽  
Bo Jiang ◽  
Hu Lin ◽  
Shuang Zhang ◽  
Zhaoyao Shi ◽  
...  
Keyword(s):  
High Precision ◽  
Measurement System ◽  
Calibration Method ◽  
Optimization Method ◽  
Rotary Table ◽  
Work Surface ◽  
Marquardt Algorithm ◽  
Angular Interval ◽  
Relationship Model ◽  
Value Decomposition

This paper proposes a calibration method for angular positioning deviation of a high-precision rotary table based on the laser tracer multi-station measurement system. The algorithm error of the calibration method for angular positioning deviation of a high-precision rotary table based on the laser tracer multi-station measurement system was mainly discussed. During the experiments, the laser tracer was fixed on the work surface of the rotary table, and the rotary was fixed on the work surface of the coordinate measurement machine (CMM). The rotary table was rotated with the same angular interval. In this case, an optimization method for calculating the coordinates of a laser tracer station by using Levenberg–Marquardt algorithm and singular value decomposition transform was proposed. Then, the angular positioning deviation of the rotary table was calibrated by an established geometric relationship model between the coordinates of laser tracer stations and the rotation angle of the rotary table. The angular positioning deviation of the high-precision rotary table was as low as ±0.9″, and the error of the calibration method was ±0.4″. The experimental results proved the feasibility of the proposed calibration method. The calibration method proposed in this paper is suitable for the case that the rotary table is not linked with the CMM, especially for large high-precision rotary tables.

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