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An intelligent automatic correlation method of oilbearing strata based on pattern constraints:An example of accretionary stratigraphy of Shishen 100 block in Shinan Oilfield of Bohai Bay Basin,East China
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作者 WU Degang WU Shenghe +1 位作者 LIU Lei SUN Yide 《Petroleum Exploration and Development》 SCIE 2024年第1期180-192,共13页
Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thic... Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thickness,an intelligent automatic correlation method of oil-bearing strata based on pattern constraints is formed.We propose to introduce knowledge-driven in automatic correlation of oil-bearing strata,constraining the correlation process by stratigraphic sedimentary patterns and improving the similarity measuring machine and conditional constraint dynamic time warping algorithm to automate the correlation of marker layers and the interfaces of each stratum.The application in Shishen 100 block in the Shinan Oilfield of the Bohai Bay Basin shows that the coincidence rate of the marker layers identified by this method is over 95.00%,and the average coincidence rate of identified oil-bearing strata reaches 90.02% compared to artificial correlation results,which is about 17 percentage points higher than that of the existing automatic correlation methods.The accuracy of the automatic correlation of oil-bearing strata has been effectively improved. 展开更多
关键词 oil-bearing strata automatic correlation contrastive learning stratigraphic sedimentary pattern marker layer similarity measuring machine conditional constraint dynamic time warping algorithm
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Automatic Measurement of Fetal Abdominal Biometric Parameters—Feasibility on a Portable Ultrasound Device 被引量:1
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作者 Naiad Hossain Khan Eva Tegnander +4 位作者 Sigurd Storve Johan Morten Dreier Sturla Eik-Nes Hans Torp Gabriel Kiss 《Open Journal of Obstetrics and Gynecology》 2017年第8期922-936,共15页
An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, t... An automatic method for measuring the fetal mean abdominal diameter (MAD) or abdominal circumference (AC) with ultrasound is proposed. From a correctly presented abdominal section suitable for MAD or AC measurement, the location of fetal abdomen is detected by image processing. Thereafter, an active contour model is converged along the abdominal boundary for measurement purposes. The validation data set contained 310 images of fetuses with gestational age (GA) from 14 to 41 weeks. The measurement success rate was 88.1%. By manually indicating the location of the abdomen, the success rate was further improved to 95.8% for the failed cases. The correlation between manual and automatic measurements was 0.95 and the intraclass correlation coefficient (ICC) was 0.976 (95% confidence interval (CI);0.969 - 0.981). The average method execution time was 0.3 s. The mean error was lower in young fetuses (0.4%) than in older fetuses (-2.1%). The proposed cross-platform method was implemented on a portable, low-cost ultrasound machine prototype targeted for low- and middle-income countries (LMIC);the results achieved were comparable to those of other state-of-the-art automatic methods. 展开更多
关键词 Portable ULTRASOUND Scanner automatic measurement Mean ABDOMINAL Diameter ABDOMINAL CIRCUMFERENCE PRENATAL ULTRASOUND ICT4D
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Adjusting precipitation measurements from the TRwS204 automatic weighing gauge in the Qilian Mountains, China 被引量:5
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作者 ZHENG Qin CHEN Ren-sheng +9 位作者 HAN Chun-tan LIU Jun-feng SONG Yao-xuan LIU Zhang-wen YANG Yong WANG Lei WANG Xi-qiang LIU Xiao-jiao GUO Shu-hai LIU Guo-hua 《Journal of Mountain Science》 SCIE CSCD 2018年第11期2365-2377,共13页
With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions ... With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions may have different effects on the performance of the precipitation gauges, it is also necessary to test the gauges in different areas. This study mainly analyzed precipitation measurements from the single-Altershielded TRwS204 automatic weighing gauge(TRwS_(SA)) relative to the adjusted manual measurements(reference precipitation) from the Chinese standard precipitation gauge in a doublefence wind shield(CSPG_(DF)) in the Hulu watershed in the Qilian Mountains, China. The measurements were compared over the period from August 2014 to July2017, and the transfer function derived from the work by Kochendorfer et al.(2017 a) for correcting windinduced losses was applied to the TRwS_(SA) measurements. The results show that the average loss of TRwS_(SA) measurements relative to the reference precipitation decreased from 0.55 mm(10.7%) to 0.51 mm(9.9%) for rainfall events, from 0.35 mm(8.5%)to 0.22 mm(5.3%) for sleet events, and from 0.49 mm(18.9%) to 0.33 mm(12.7%) for snowfall events after adjustment. The uncorrected large biases of TRwS_(SA) measurements are considered to be mainly caused by specific errors of TRwS_(SA), different gauge orifice area and random errors. These types of errors must be considered when comparing precipitation measurements for different gauge types, especially in the mountains. 展开更多
关键词 中国标准 计量器 降水 调整 区域测试 气象站 优先级 分水岭
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Automatic Detection and Measurement of Fetal Biparietal Diameter and Femur Length —Feasibility on a Portable Ultrasound Device
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作者 Naiad Hossain Khan Eva Tegnander +3 位作者 Johan Morten Dreier Sturla Eik-Nes Hans Torp Gabriel Kiss 《Open Journal of Obstetrics and Gynecology》 2017年第3期334-350,共17页
An automatic method able to recognize a presented section through the biparietal plane of the fetal head and a section through the fetal femur in ultrasound images is developed. Once the correct anatomical section for... An automatic method able to recognize a presented section through the biparietal plane of the fetal head and a section through the fetal femur in ultrasound images is developed. Once the correct anatomical section for measurement is identified by the machine, the placement of the measurement calipers is automatically determined by fitting an active contour model to the structure of interest. The fetal biparietal diameter (BPD) and femur length (FL) are then measured automatically. The validation data set contained 167 and 197 B-mode images for BPD and FL measurements, respectively. The images were acquired using 4 different ultrasound scanners, which resulted in varied image quality and gain settings. The mean gestational age (GA) of the fetuses was 19.4 weeks, range 16 to 41 weeks. A measurement success rate of 90% was achieved for both BPD and FL. The correlation coefficients between the manual and automatic measurements were 0.995 (BPD) and 0.967 (FL), mean errors were 0.5 mm (BPD) and -1.7 mm (FL) and error range with 95% confidence interval (CI) were ﹣3.8 - 4.8 mm (BPD) and ﹣11.4 - 8.1 mm (FL). The automatic measurement results were consistent in both high and low gain settings. The intraclass correlation coefficients between manual and automatic measurements were 0.995 (95% CI;0.981 - 0.999) for BPD in high gain, 1.0 (95% CI;0.998 - 1.0) for BPD in low gain, 0.998 (95% CI;0.991 - 0.999) for FL in high gain and 0.999 (95% CI;0.996 - 1.0) for FL in low gain settings. The method was implemented on a prototype, portable ultrasound machine designed to be used in low- and middle-income countries (LMIC). The overall performance of the method supports our hypothesis that automated methods can be used and are beneficial in a clinical setting. 展开更多
关键词 FETAL DATING Biparietal DIAMETER FEMUR Length PORTABLE Ultrasound Machine automatic measurement
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Automatic measurement of air-pressure sensor based on two-pressure control instrument
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作者 丁红英 赵湛 +1 位作者 轩运动 方震 《Journal of Measurement Science and Instrumentation》 CAS 2013年第1期6-9,共4页
To measure the performance of high precision air-pressure sensors in below normal pressure,an automatic measurement instrument has been designed and implemented.It can simulate environment of low pressure from 300hPa ... To measure the performance of high precision air-pressure sensors in below normal pressure,an automatic measurement instrument has been designed and implemented.It can simulate environment of low pressure from 300hPa to 1 000hPa with high accuracy by proportional-integral-derivative(PID)control quickly,and it can also generate various relative humidity by two-pressure control.The results show that this instrument can reach controlled pressure quickly.And it works well with the minimum average pressure difference,and the fluctuation is±0.02hPa at 500hPa.And it can keep in a stable status for a long time.It works well in performance testing of pressure sensors.The structure of the system is simple,takes small investment,and can be operated conveniently. 展开更多
关键词 automatic measurement two-pressure pressure sensor proportional integral derivative(PID)control
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Design of a Modularized Automatic Measurement and Control System for LaserInduced Breakdown Spectrometer
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作者 丁宇 田地 +2 位作者 陈飞鹏 乔淑君 杨光 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期406-410,共5页
In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and cont... In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and control system was developed. Based on the characteristics of each LIBS component, the following development steps have been performed:( 1) a summary of characteristic parameters of the component are established;( 2) the integration mechanism of multiple electrical interfaces is designed;( 3) the component control instruction library is developed. The experimental results indicate that the measurement and control system is compatible with most LIBS parts in the market.Spectrometer and laser can be compatible with at least three different types of parts. In addition,a multilayer iterative testing process is designed to improve the efficiency of optimization process of LIBS parameters. The experimental results have shown that the automatic optimization of the delay time compared to the manual testing provides significant gain in testing efficiency. The range of delay time in the experiments is 1. 28 to 10. 28 μs and the step value is 1,0. 5,0. 2 and 0. 1 μs. The gain in testing efficiency has been found to be increased by 73. 76%,75. 93%,78. 81% and 80. 42%,respectively. 展开更多
关键词 automatic control technique laser-induced breakdown spectroscopy(LIBS) measurement and control system(MCS) COMPONENT
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Measurement of Stone Diameter with Three Sizes of Automatically Fixating Stone Baskets
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作者 Jens Cordes Felix Nguyen +1 位作者 Wolfgang Pinkowski Dieter Jocham 《Open Journal of Urology》 2013年第2期58-61,共4页
Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is s... Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is sometimes difficult for surgeons to estimate stone size and therefore give prognostic advises. The visual perception of the stone size depends on the shape, colour, distance to the renoscope and dilatation of the ureter. This is the so-called binding problem, because shape, color and direction of motion are processed separately by different population of optical neurons. In order to establish a better prognostic rational especially for less experienced surgeons, we established an intra operative semi-quantitative measurement of the stone size supported by a stone basket. Materials and Methods: We modified the tipped, nitinol stone baskets from the company Urotech with diameters of 2.5, 3.0 and 4 FR. The handle of this basket has a spring mechanism, which automatically closes the basket and provides a predefined fixation force of the stones within the basket. On the handle we established a non-linear scale in mm by grabbing standardized balls or standardized screws. Result: The scales are nonlinear because of the nonlinear relation between the diameter of the stone and the distance of the slider. Also the scales differ in between the basket size, because of the different strain conditions due to the different wire sizes and materials or the spring and basket. Conclusion: This scale could be an important orientation for a surgeon during endourological procedures to estimate stone sizes. After further clinical experience a semi-quantitative visualization like green, yellow and red colors could help to predict potential complications due to large stone sizes. Finally it could bevery interesting for other disciplines like gastroenterology. 展开更多
关键词 STONE Basket automaticALLY Fixating STONE Basket measurement of STONE SIZE
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Design of mobile sensing system for automatical measurement
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作者 ZHU Jun-jiang HE Ling-song 《Journal of Measurement Science and Instrumentation》 CAS 2014年第2期68-75,共8页
移动设备人机交互能力较差且计算能力有限,因此开发基于移动设备的测量系统的难度较高。本文设计了一种移动传感系统,它具备构件、配置和运行测量程序的功能,由移动设备和传感器探头两部分组成。在移动设备中安装了小型化虚拟仪器平台,... 移动设备人机交互能力较差且计算能力有限,因此开发基于移动设备的测量系统的难度较高。本文设计了一种移动传感系统,它具备构件、配置和运行测量程序的功能,由移动设备和传感器探头两部分组成。在移动设备中安装了小型化虚拟仪器平台,该平台具有面向对象的架构,并可以通过XML文件进行配置,且这些配置文件可以被写入传感器探头。因此,探头和移动设备之间可以通过自组网形成测量系统。为测试该系统的性能,本文基于某安卓手机和一个测量探头设计了声音采集和柔性力测量程序,体现出移动传感平台具备可重构、自动化和柔性化程度高的特点。 展开更多
关键词 移动传感系统 自动化测量 可重构 XML 小型化虚拟仪器平台
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Automatic Recognition Method for Optical Measuring Instruments Based on Machine Vision 被引量:2
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作者 宋乐 林玉池 郝立果 《Transactions of Tianjin University》 EI CAS 2008年第3期202-207,共6页
Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, ... Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, a 2-layer automatic recognition model for data reading is established after adopting a series of pre-processing algorithms. This model is an optimal combination of the correlation-based template matching method and a concurrent back propagation(BP) neural network. Multiple complementary feature extraction is used in generating the eigenvectors of the concurrent network. In order to improve fault-tolerance capacity, rotation invariant features based on Zernike moments are extracted from digit characters and a 4-dimensional group of the outline features is also obtained. Moreover, the operating time and reading accuracy can be adjusted dy-namically by setting the threshold value. The experimental result indicates that the newly developed algorithm has optimal recognition precision and working speed. The average reading ratio can achieve 97.23%. The recognition method can automatically obtain the results of optical measuring instruments rapidly and stably without modifying their original structure, which meets the application requirements. 展开更多
关键词 机器视觉 自动识别 光学测量工具 神经网络
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Method of Predicting Water Content in Crude Oil Based on Measuring Range Automatic Switching
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作者 陈祥光 朱文博 +1 位作者 赵军 任磊 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期87-91,共5页
Water content in output crude oil is hard to measure precisely because of wide range of dielectric coefficient of crude oil caused by injected dehydrating and demulsifying agents.The method to reduce measurement error... Water content in output crude oil is hard to measure precisely because of wide range of dielectric coefficient of crude oil caused by injected dehydrating and demulsifying agents.The method to reduce measurement error of water content in crude oil proposed in this paper is based on switching measuring ranges of on-line water content analyzer automatically.Measuring precision on data collected from oil field and analyzed by in-field operators can be impressively improved by using back propogation (BP) neural network to predict water content in output crude oil.Application results show that the difficulty in accurately measuring water-oil content ratio can be solved effectively through this combination of on-line measuring range automatic switching and real time prediction,as this method has been tested repeatedly on-site in oil fields with satisfactory prediction results. 展开更多
关键词 water content in crude oil prediction method BP network measuring range automatic switching
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AN AUTOMATIC HEAT FLUX-TEMPERATURE MEASURING SYSTEM AND ITS APPLICATION
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作者 Lu Shunchang Mao Fangguan Engineers, Naval Medical Research Institute, P. L. A., Shanghai 《China Ocean Engineering》 SCIE EI 1989年第3期375-382,共8页
An automatic heat flux-temperature measuring system can be used to measure local body heat flux, local skin temperature, body core temperature, and ambient temperature, as well as mean body heat flux, mean skin temper... An automatic heat flux-temperature measuring system can be used to measure local body heat flux, local skin temperature, body core temperature, and ambient temperature, as well as mean body heat flux, mean skin temperature, physiological shell thermal insulation and suit thermal insulation. This paper describes the measuring principle, hardware construction, software program and the application in thermal measurements on divers. 展开更多
关键词 AN automatic HEAT FLUX-TEMPERATURE measurING SYSTEM AND ITS APPLICATION HEAT BODY ITS
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Study on Factors Influencing the Quality of Automatic Monitoring Data of Pollution Sources and Technical Assurance Measures
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作者 Hanju BAO Yun WU Chengxin PAN 《Meteorological and Environmental Research》 CAS 2021年第6期53-58,共6页
Automatic monitoring data of pollution sources is an important basis for environmental supervision and management.At present,it is difficult to guarantee the quality of automatic monitoring data of pollution sources,a... Automatic monitoring data of pollution sources is an important basis for environmental supervision and management.At present,it is difficult to guarantee the quality of automatic monitoring data of pollution sources,and it is difficult to play the role of the monitoring data.In response to this problem,the factors influencing the quality of automatic monitoring data of pollution sources were analyzed in detail,and technical assurance measures for the quality of automatic monitoring data of pollution sources in Shandong Province were studied.Besides,the dynamic management and control idea of automatic monitoring of pollution sources was proposed,and specific technical measures were analyzed from five aspects of standardizing automatic monitoring equipment of pollution sources,improving the data collection and transmission system,establishing a mechanism for reporting operating status information of monitoring equipment,setting alarm rules and alarm processing procedures,and statistically analyzing the operating status of the equipment.Practice has proved that the dynamic management and control system can effectively ensure the quality of automatic monitoring data of pollution sources. 展开更多
关键词 automatic monitoring Quality assurance Technical measures Dynamic management and control
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Intelligent Segmentation and Measurement Model for Asphalt Road Cracks Based on Modified Mask R-CNN Algorithm 被引量:4
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作者 Jiaxiu Dong Jianhua Liu +4 位作者 Niannian Wang Hongyuan Fang Jinping Zhang Haobang Hu Duo Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第8期541-564,共24页
Nowadays, asphalt road has dominated highways around the world. Among various defects of asphalt road, crackshave been paid more attention, since cracks often cause major engineering and personnel safety incidents. Cu... Nowadays, asphalt road has dominated highways around the world. Among various defects of asphalt road, crackshave been paid more attention, since cracks often cause major engineering and personnel safety incidents. Currentmanual crack inspection methods are time-consuming and labor-intensive, and most segmentation methods cannot detect cracks at the pixel level. This paper proposes an intelligent segmentation and measurement model basedon the modified Mask R-CNN algorithm to automatically and accurately detect asphalt road cracks. The modelproposed in this paper mainly includes a convolutional neural network (CNN), an optimized region proposalnetwork (RPN), a region of interest (RoI) Align layer, a candidate area classification network and a Mask branch offully convolutional network (FCN). The ratio and size of anchors in the RPN are adjusted to improve the accuracyand efficiency of segmentation. Soft non-maximum suppression (Soft-NMS) algorithm is developed to improvethe segmentation accuracy. A dataset including 8,689 images (512× 512 pixels) of asphalt cracks is established andthe road crack is manually marked. Transfer learning is used to initialize the model parameters in the trainingprocess. To optimize the model training parameters, multiple comparison experiments are performed, and the testresults show that the mean average precision (mAP) value and F1-score of the optimal trained model are 0.952 and0.949. Subsequently, the robustness verification test and comparative test of the trained model are conducted andthe topological features of the crack are extracted. Then, the damage area, length and average width of the crackare measured automatically and accurately at pixel level. More importantly, this paper develops an automatic crackdetection platform for asphalt roads to automatically extract the number, area, length and average width of cracks,which can significantly improve the crack detection efficiency for the road maintenance industry. 展开更多
关键词 Asphalt road cracks intelligent segmentation automatic measurement deep learning Mask R-CNN
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Easy calibration method of vision system for in-situ measurement of strain of thin films 被引量:3
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作者 Jun-Hyub PARK Dong-Joong KANG +5 位作者 Myung-Soo SHIN Sung-Jo LIM Son-Cheol YU Kwang-Soo LEE Jong-Eun HA Sung-Hoon CHOA 《中国有色金属学会会刊:英文版》 CSCD 2009年第B09期243-249,共7页
An easy calibration method was presented for in-situ measurement of displacement in the order of nanometer during micro-tensile test for thin films by using CCD camera as a sensing device. The calibration of the sensi... An easy calibration method was presented for in-situ measurement of displacement in the order of nanometer during micro-tensile test for thin films by using CCD camera as a sensing device. The calibration of the sensing camera in the system is a central element part to measure displacement in the order of nanometer using images taken with the camera. This was accomplished by modeling the optical projection through the camera lens and relative locations between the object and camera in 3D space. A set of known 3D points on a plane where the film is located on is projected to an image plane as input data. These points, known as a calibration points, are then used to estimate the projection parameters of the camera. In the measurement system of the micro-scale by CCD camera, the calibration data acquisition and one-to-one matching steps between the image and 3D planes need precise data extraction procedures and repetitive user's operation to calibrate the measuring devices. The lack of the robust image feature extraction and easy matching prevent the practical use of these methods. A data selection method was proposed to overcome these limitations and offer an easy and convenient calibration of a vision system that has the CCD camera and the 3D reference plane with calibration marks of circular type on the surface of the plane. The method minimizes the user's intervention such as the fine tuning of illumination system and provides an efficient calibration method of the vision system for in-situ axial displacement measurement of the micro-tensile materials. 展开更多
关键词 标定方法 视觉系统 原位测试 应变 薄膜
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Automatic Partition of Chinese Sentence Group 被引量:3
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作者 陈怡疆 史晓东 周昌乐 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期177-180,共4页
Automatic partition of Chinese sentence group is very important to the statistical machine translation system based on discourse. This paper presents an approach to this issue:first,each sentence in a discourse is exp... Automatic partition of Chinese sentence group is very important to the statistical machine translation system based on discourse. This paper presents an approach to this issue:first,each sentence in a discourse is expressed as a feature vector; second,a special hierarchical clustering algorithm is applied to present a discourse as a sentence group tree. In this paper,local reoccurrence measure is proposed to the selection of key phrases and the evaluation of the weight of key phrases. Experimental results show our approach promising. 展开更多
关键词 句子组 句子组的自动分区 判组树 本地出现措施
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An Automatic Synchronization Method for Distributed Power Electronics System
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作者 Cheng Zhang Chi Sun Sheng Ai 《Energy and Power Engineering》 2013年第3期24-27,共4页
Currently, the high-speed serial fiber-optic ring net communication is a main method for performing the distributed control network topology and control mode. Because of a network transmission delay inherent in the to... Currently, the high-speed serial fiber-optic ring net communication is a main method for performing the distributed control network topology and control mode. Because of a network transmission delay inherent in the topology, synchronization between nodes has become a critical issue which needs to be studied. The existing synchronization methods largely depend on the complex communication protocol. Therefore, this paper has proposed a method of automatic measurement and compensation of synchronization delay, and analyzed its operating principle and implementation procedure in detail. The results obtained from the experiments prove the proposed method to be correct, effective and practicable. 展开更多
关键词 Power ELECTRONICS CONVERTER System(PECS) Distributed Control DELAY automatic measurement SYNCHRONIZATION
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Design of Automatic Batch Calibration and Correction System for IMU
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作者 Lihua Zhu Qifan Yun +1 位作者 Zhiqiang Wu Cheire Cheng 《Computers, Materials & Continua》 SCIE EI 2022年第4期1489-1501,共13页
Thanks to its light weight,low power consumption,and low price,the inertial measurement units(IMUs)have been widely used in civil and military applications such as autopilot,robotics,and tactical weapons.The calibrati... Thanks to its light weight,low power consumption,and low price,the inertial measurement units(IMUs)have been widely used in civil and military applications such as autopilot,robotics,and tactical weapons.The calibration is an essential procedure before the IMU is put in use,which is generally used to estimate the error parameters such as the bias,installation error,scale factor of the IMU.Currently,the manual one-by-one calibration is still the mostly used manner,which is low in efficiency,time-consuming,and easy to introduce mis-operation.Aiming at this issue,this paper designs an automatic batch calibration method for a set of IMUs.The designed automatic calibration master controller can control the turntable and the data acquisition system at the same time.Each data acquisition front-end can complete data acquisition of eight IMUs one time.And various scenarios of experimental tests have been carried out to validate the proposed design,such as the multi-position tests,the rate tests and swaying tests.The results illustrate the reliability of each function module and the feasibility automatic batch calibration.Compared with the traditional calibration method,the proposed design can reduce errors caused by the manual calibration and greatly improve the efficiency of IMU calibration. 展开更多
关键词 MEMS inertial measurement unit batch calibration automatic calibration
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Automatic System for Failure Detection in Hydro-Power Generators
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作者 Luis Carlos Ribeiro Levy Ely de Lacerda de Oliveira +4 位作者 Erik Leandro Bonaldi Luiz Eduardo Borges da Silva Camila Paes Salomon Jonas G. Borges da Silva Germano Lambert-Torres 《Journal of Power and Energy Engineering》 2014年第4期36-46,共11页
This paper presents an automatic system for failure detection in hydro-power generators. The main idea of this system is to detect failure using current and voltage signals acquired without any type of internal interf... This paper presents an automatic system for failure detection in hydro-power generators. The main idea of this system is to detect failure using current and voltage signals acquired without any type of internal interference in the generator operation. The detected failures could be mechanical or electrical origins, such as: problems in bearings, unwanted vibrations, partial discharges, misalignment, unbalancing, among others. It is possible because the generator acts as a transducer for mechanical problems, and they appear in current and voltage signals. This automatic system based on electric signature analysis has been installed in Itapebi Power Plant generators since 2012. Some results are presented in this paper. 展开更多
关键词 automatic System ON-LINE measurements Digital SIGNAL Processing PREDICTIVE Maintenance FAILURE Detection
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MC-LRF based pose measurement system for shipborne aircraft automatic landing
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作者 Zhuo ZHANG Qiufu WANG +2 位作者 Daoming BI Xiaoliang SUN Qifeng YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第8期298-312,共15页
Due to the portability and anti-interference ability,vision-based shipborne aircraft automatic landing systems have attracted the attention of researchers.In this paper,a Monocular Camera and Laser Range Finder(MC-LRF... Due to the portability and anti-interference ability,vision-based shipborne aircraft automatic landing systems have attracted the attention of researchers.In this paper,a Monocular Camera and Laser Range Finder(MC-LRF)-based pose measurement system is designed for shipborne aircraft automatic landing.First,the system represents the target ship using a set of sparse landmarks,and a two-stage model is adopted to detect landmarks on the target ship.The rough 6D pose is measured by solving a Perspective-n-Point problem.Then,once the rough pose is measured,a region-based pose refinement is used to continuously track the 6D pose in the subsequent image sequences.To address the low accuracy of monocular pose measurement in the depth direction,the designed system adopts a laser range finder to obtain an accurate range value.The measured rough pose is iteratively optimized using the accurate range measurement.Experimental results on synthetic and real images show that the system achieves robust and precise pose measurement of the target ship during automatic landing.The measurement means error is within 0.4in rotation,and 0.2%in translation,meeting the requirements for automatic fixed-wing aircraft landing. 展开更多
关键词 automatic landing Dataprocessingand image processing Laser range finder Monocular camera Pose measurement
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Automatic Sentiment Classification of News Using Machine Learning Methods
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作者 Yuhan Wang 《Modern Electronic Technology》 2022年第1期7-11,共5页
With the rapid development of social economy,the society has entered into a new stage of development,especially in new media under the background of rapid development,makes the importance of news and information to ge... With the rapid development of social economy,the society has entered into a new stage of development,especially in new media under the background of rapid development,makes the importance of news and information to get the comprehensive promotion,and in order to further identify the positive and negative news,should be fully using machine learning methods,based on the emotion to realize the automatic classifying of news,in order to improve the efficiency of news classification.Therefore,the article first makes clear the basic outline of news sentiment classification.Secondly,the specific way of automatic classification of news emotion is deeply analyzed.On the basis of this,the paper puts forward the concrete measures of automatic classification of news emotion by using machine learning. 展开更多
关键词 Machine learning automatic classification of news sentiment Specific measures
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