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XMAC仪器与LCZ-1陀螺仪并测的实现
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作者 牛宏斌 《国外测井技术》 2019年第3期73-74,共2页
LCZ-1陀螺仪可以挂接在ECLIPS-5700测井系统下,实现套管井的井斜、方位数据测量。但是,LCZ-1陀螺仪是一个独立的个体,和其它仪器没有数据上的关联。本文通过分析研究,使LCZ-1陀螺仪和XMAC仪器成功挂接,大大提高了LCZ-1陀螺仪的应用前景。
关键词 XMAC LCZ-1 挂接 并测
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NDLS-3000网络双测井系统解决声感并测干扰的方法
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作者 陈金宏 董军 +1 位作者 贺伦 李庆军 《石油仪器》 2005年第5期36-38,共3页
声感并测时,特别是测高阻地层或遇到测井电缆性能不好时,声波同步对中感应、八侧向曲线存在严重的干扰。NDLS-3000网络双测井系统为了解决声感并测干扰,通过应用可控定时采样和间隔可控声波同步技术,改变了直流板采样方式和声波板声波... 声感并测时,特别是测高阻地层或遇到测井电缆性能不好时,声波同步对中感应、八侧向曲线存在严重的干扰。NDLS-3000网络双测井系统为了解决声感并测干扰,通过应用可控定时采样和间隔可控声波同步技术,改变了直流板采样方式和声波板声波同步产生方式,在满足采样精度要求的情况下,获得了最佳的并测效果。 展开更多
关键词 声感并测 可控定时采样 间隔可控声波同步 NDLS-3000网络双井系统
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基于对半组合法的导弹绝缘电阻测试
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作者 卢文忠 张磊 冀海燕 《弹箭与制导学报》 CSCD 北大核心 2009年第4期248-250,共3页
导弹检测过程中的绝缘电阻测试是一项重要工作。现常用的测试方法有分测法、并测法,可较准确地完成这项工作,但这两种方法操作步骤多、耗费时间长。经过数学分析,提出了一种新的测试方法:对半组合法,经实例表明:该方法可减少操作步骤,... 导弹检测过程中的绝缘电阻测试是一项重要工作。现常用的测试方法有分测法、并测法,可较准确地完成这项工作,但这两种方法操作步骤多、耗费时间长。经过数学分析,提出了一种新的测试方法:对半组合法,经实例表明:该方法可减少操作步骤,大大缩短导弹绝缘电阻测试时间。 展开更多
关键词 绝缘电阻 并测 对半组合法
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数字电极测井仪分析
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作者 李园媛 《国外测井技术》 2020年第5期23-26,共4页
数字电极仪器是一种新式测井仪器,在满足探测深度及地层响应的同时,实现了井下供电、测量,并能与其它仪器实现并测。由于该仪器采用数字传输技术减少了干扰,同时取消了传统测井所用的步进器,改变了以往普通电阻率单独测量的局面。
关键词 数字电极 井仪器 并测
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ATE中的浮动V/I源 被引量:2
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作者 孙铣 《中国集成电路》 2011年第11期55-63,共9页
本文论述了浮动V/I源和共地V/I源的构造区别,及在开尔文检测和多工位并测方面的差异,论述了浮动V/I源的各种类型和应用优势,并分析了浮动V/I源的共模干扰和与此相关的一些认识误区。关键词:浮动V/I源;共地V/I源;多工位并测;
关键词 浮动V/I源 共地V/I源 多工位并测 共模干扰
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30Gbit/s Parallel Optical Receiver Module
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作者 陈弘达 贾九春 +1 位作者 裴为华 唐君 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期696-699,共4页
A 30Gbit/s receptor module is developed with a CMOS integrated receiver chip(IC) and a GaAs-based 1 × 12 photo detector array of PIN-type. Parallel technology is adopted in this module to realize a high-speed r... A 30Gbit/s receptor module is developed with a CMOS integrated receiver chip(IC) and a GaAs-based 1 × 12 photo detector array of PIN-type. Parallel technology is adopted in this module to realize a high-speed receiver module with medium speed devices. A high-speed printed circuit board(PCB) is designed and produced. The IC chip and the PD array are packaged on the PCB by chip-on-board technology. Flip chip alignment is used for the PD array accurately assembled on the module so that a plug-type optical port is built. Test results show that the module can receive parallel signals at 30Gbit/s. The sensitivity of the module is - 13.6dBm for 10^-13 BER. 展开更多
关键词 receiver module PARALLEL PD array
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航天飞行器分析、排除故障三十六计(续2)
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作者 王觉先 《质量与可靠性》 1998年第5期27-29,共3页
第十五计 双台并测 在对弹上仪器进行测试并发现故障时,有时怀疑地面测试设备质量不稳,这时可以更换一台地面测试设备再进行测试。但有些故障时隐时现或测试数据时大时小,因而在分别进行测量时,无法进行比较,不能判定弹上被测设备有无... 第十五计 双台并测 在对弹上仪器进行测试并发现故障时,有时怀疑地面测试设备质量不稳,这时可以更换一台地面测试设备再进行测试。但有些故障时隐时现或测试数据时大时小,因而在分别进行测量时,无法进行比较,不能判定弹上被测设备有无问题。 展开更多
关键词 航天飞行器 故障排除 双台并测 两站对比
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DC LOOP-CURRENT DETECTING AND RESTRAINING METHODS FOR PARALLEL INVERTER SYSTEM
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作者 陈良亮 肖岚 严仰光 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期1-6,共6页
DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the pa... DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance. 展开更多
关键词 DC loop-current DETECT digital adjustment parallel inverter
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CFD aided investigation of single droplet coalescence 被引量:2
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作者 Felix Gebauer Mark W.Hlawitschka Hans-Jorg Bart 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期249-252,共4页
This article describes the development of a coalescence model using various CFD work packages,and is validated using as toluene water model system.Numerical studies were performed to describe droplet interactions in l... This article describes the development of a coalescence model using various CFD work packages,and is validated using as toluene water model system.Numerical studies were performed to describe droplet interactions in liquid–liquid test systems.Current models use adjustable parameters to describe these phenomena.The research in the past decades led to different correlations to model coalescence and breakage depending on the chemical system and the apparatus geometry.Especially the complexity of droplet coalescence requires a detailed investigation of local phenomena during the droplet interaction.Computational fluid dynamics(CFD) studies of single droplet interactions were performed and validated with experimental results to improve the understanding of the local hydrodynamics and film drainage during coalescence.The CFD simulations were performed for the interaction of two differently sized droplets at industrial relevant impact velocities.The experimental verification and validation of the numerical results were done with standardized high-speed imaging studies by using a special test cell with a pendant and a free rising droplet.An experimental based algorithm was implemented in the open source code OpenF OAM to account for the contact time and the dimple formation.The standard European Federation of Chemical Engineering(EFCE) test system toluene/water was used for the numerical studies and the experimental investigations as well.The results of the CFD simulations are in good accordance with the observed coalescence behavior in the experimental studies.In addition,a detailed description of local phenomena,like film rupture,velocity gradients,pressures and micro-droplet entrainment could be obtained. 展开更多
关键词 CFD Parameter estimation COALESCENCE Film drainage
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Serological Diagnosis of Liver Metastasis in Patients with Breast Cancer 被引量:6
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作者 Rui Cao Li-ping Wang 《Clinical oncology and cancer researeh》 CAS CSCD 2012年第1期57-62,共6页
Objective To diagnose and explore the serological diagnostic factors for liver metastasis in patients with breast cancer before symptoms occur. Methods A total of 430 female in-patients with breast cancer of stages 0 ... Objective To diagnose and explore the serological diagnostic factors for liver metastasis in patients with breast cancer before symptoms occur. Methods A total of 430 female in-patients with breast cancer of stages 0 to IIIC who came to Tianjin Medical University Cancer Institute and Hospital from January 2003 to January 2004 were studied and followed up until May 2011. Serum levels of biochemical markers for tumor and liver were measured at the time of diagnosis. Results Liver metastasis was more likely to occur in patients with stage Ill cancer or c-erbB-2-positive expression. Alanine aminotransferase, aspartate aminotransferase, ~/-glutamyltransferase (GGT), alkaline phosphatase, lactate dehvdrogenase (LDH), and carbohydrate antigen 1153 (CA153) levels were significantly higher in patients with liver metastasis than those without liver metastasis. Diagnostic indices of LDH, GGT, and CA153 were 174 U/L, 32 U/L, and 26.48 Dg/L, respectively. The areas under the curves of LDH, GGT, and CEA were 0.795, 0.784, and 0.661, respectively, and sensitivities of parallel tests for LDH and CA153 and for GGT and CA153 were 88.6% and 85.7 %, respectively. The specificity of serial tests for both pairs of enzymes was 97.7%. Conclusions Tile sensitivity and specificity of combined tumor and biochemical markers could be used as indicators during screening for breast-liver metastasis. 展开更多
关键词 breast neoplasms LIVER neoplasm metastasis OXIDOREDUCTASES GAMMA-GLUTAMYLTRANSFERASE
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Parallel Test Tasks Scheduling and Resources Configuration Based on GA-ACA 被引量:3
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作者 方甲永 薛辉辉 肖明清 《Journal of Measurement Science and Instrumentation》 CAS 2011年第4期321-326,共6页
A Genetic Algorithm-Ant Colony Algorithm(GA-ACA),which can be used to optimize multi-Unit Under Test(UUT)parallel test tasks sequences and resources configuration quickly and accurately,is proposed in the paper.With t... A Genetic Algorithm-Ant Colony Algorithm(GA-ACA),which can be used to optimize multi-Unit Under Test(UUT)parallel test tasks sequences and resources configuration quickly and accurately,is proposed in the paper.With the establishment of the mathematic model of multi-UUT parallel test tasks and resources,the condition of multi-UUT resources mergence is analyzed to obtain minimum resource requirement under minimum test time.The definition of cost efficiency is put forward,followed by the design of gene coding and path selection project,which can satisfy multi-UUT parallel test tasks scheduling.At the threshold of the algorithm,GA is adopted to provide initial pheromone for ACA,and then dual-convergence pheromone feedback mode is applied in ACA to avoid local optimization and parameters dependence.The practical application proves that the algorithm has a remarkable effect on solving the problems of multi-UUT parallel test tasks scheduling and resources configuration. 展开更多
关键词 parallel test Genetic Algorithm-Ant Colony Algo-rithm GA-ACA cost efficiency multi-UnitUnder Test UUT resources configuration tasks scheduling
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Off-shell BRST-VSUSY Superalgebra for D = 4 BF Theories in Superconnection Formalism 被引量:1
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作者 A. Aidaoui M. Tahiri 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期309-312,共4页
We propose the supereonneetion formalism to construct the off-shell BRST-VSUSY superalgebra for D = 4 BF theories. The method is based on the natural introduction of physical fields as well as auxiliary fields via sup... We propose the supereonneetion formalism to construct the off-shell BRST-VSUSY superalgebra for D = 4 BF theories. The method is based on the natural introduction of physical fields as well as auxiliary fields via supereon- neetions and their associated supereurvatures defined on a superspaee. We also give a prescription to build the off-shell BRST-VSUSY exact quantum action. 展开更多
关键词 superconnection off-shell BRST-VSUSY superalgebra BF theories
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Multidisciplinary imaging of liver hydatidosis 被引量:10
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作者 Gianluca Marrone Francesca Crino' +6 位作者 Settimo Caruso Giuseppe Mamone Vincenzo Carollo Mariapina Milazzo Salvatore Gruttadauria Angelo Luca Bruno Gridelli 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第13期1438-1447,共10页
Liver hydatidosis is a parasitic endemic disease affecting extensive areas in our planet, a significant stigma within medicine to manage because of its incidence, possible complications, and diagnostic involvements. T... Liver hydatidosis is a parasitic endemic disease affecting extensive areas in our planet, a significant stigma within medicine to manage because of its incidence, possible complications, and diagnostic involvements. The diagnosis of liver hydatidosis should be as fast as possible because of the relevant complications that may arise with disease progression, involving multiple organs and neighboring structures causing disruption, migration, contamination. The aim of this essay is to illustrate the role of imaging as ultrasonography (US), multi detector row computed tomography, and magnetic resonance imaging (MRI) in the evaluation of liver hydatidosis: the diagnosis, the assessment of extension, the identification of possible complications and the monitoring the response to therapy. US is the screening method of choice. Computed tomography (CT) is indi-cated in cases in which US is inadequate and has high sensitivity and specificity for calcified hydatid cysts. Magnetic resonance is the best imaging procedure to demonstrate a cystic component and to show a biliary tree involvement. Diagnostic tests such as CT and MRI are mandatory in liver hydatidosis because they allow thorough knowledge regarding lesion size, location, and relations to intrahepatic vascular and biliary structures, providing useful information for effective treatment and decrease in post-operative morbidity. Hydatid disease is classified into four types on the basis of their radiologic appearance. 展开更多
关键词 Liver hydatidosis Hepatic cyst Daughtercysts Calcified cyst Pericyst
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Management of Pregnancy with Ankylosing Spondylitis 被引量:1
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作者 Qian Zhou Xu-ming Bian Jun-tao Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第1期46-49,共4页
Objective To discuss the interaction between pregnancy and ankylosing spondylitis, and the management of pregnancy with ankylosing spondylitis. Methods Twelve cases of pregnancy with ankylosing spondylitis in Peking U... Objective To discuss the interaction between pregnancy and ankylosing spondylitis, and the management of pregnancy with ankylosing spondylitis. Methods Twelve cases of pregnancy with ankylosing spondylitis in Peking Union Medical College Hospital from September 2004 to July 2011 were analyzed retrospectively, focusing on the arteritis condition, pregnancy complications, and outcomes. Results All the 12 patients had full-term pregnancy. Five cases gave birth naturally, and 7 cases received cesarean section for maternity factors. No adverse pregnancy outcomes were encountered. Waist pain appeared in 2 cases in the second trimester, for both of which medication failed. One of the 2 cases had natural childbirth, while the other maintained pregnancy smoothly to cesarean section. Conclusions Pregnancy monitoring can help obtain favorable pregnancy outcomes. Attention should be paid to postpartum change of the illness. 展开更多
关键词 ankylosing spondylitis PREGNANCY pregnancy outcome
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Design of Parallel Electrical Resistance Tomography System for Measuring Multiphase Flow 被引量:3
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作者 董峰 许聪 +1 位作者 张志强 任尚杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期368-379,共12页
ERT(electrical resistance tomography) is effective method for visualization of multiphase flows,offering some advantages of rapid response and low cost,so as to explore the transient hydrodynamics.Aiming at this targe... ERT(electrical resistance tomography) is effective method for visualization of multiphase flows,offering some advantages of rapid response and low cost,so as to explore the transient hydrodynamics.Aiming at this target,a fully programmable and reconfigurable FPGA(field programmable gate array)-based Compact PCI(peripheral component interconnect) bus linked sixteen-channel ERT system has been presented.The data acquisition system is carefully designed with function modules of signal generator module;Compact PCI transmission module and data processing module(including data sampling,filtering and demodulating).The processing module incorporates a powerful FPGA with Compact PCI bus for communication,and the measurement process management is conducted in FPGA.Image reconstruction algorithms with different speed and accuracy are also coded for this system.The system has been demonstrated in real time(1400 frames per second for 50 kHz excitation) with signal-noise-ratio above 62 dB and repeatability error below 0.7%.Static experiments have been conducted and the images manifested good resolution relative to the actual object distribution.The parallel ERT system has provided alternative experimental platform for the multiphase flow measurements by the dynamic experiments in terms of concentration and velocity. 展开更多
关键词 electrical resistance tomography data acquisition compact peripheral component interconnect field programmable gate array digital filter digital demodulation
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Self-Assembled Monolayer of Lipoic Acid on Gold and Its Application to Rapid Determination of 2, 3, 7, 8-Tetrachlorodibenzo-p-Dioxin 被引量:1
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作者 刘宪华 杨娇凤 +2 位作者 张林 刘洪喜 鲁逸人 《Transactions of Tianjin University》 EI CAS 2013年第4期248-254,共7页
Lipoic acid (LA) has received great attention in the area of gold surface functionalization. In this study, LA was employed as a linker for the attachment of antibody to the gold surface of surface plasmon resonance (... Lipoic acid (LA) has received great attention in the area of gold surface functionalization. In this study, LA was employed as a linker for the attachment of antibody to the gold surface of surface plasmon resonance (SPR) chip. By using this chip in a homemade SPR immunosensor, low molecular weight compound 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) can be detected at a low level of 0.01 ng/mL. There is a good linear relationship(R2 =0.943 1) between the results of SPR biosensor and enzyme-linked immunosorbent assay(ELISA). 展开更多
关键词 lipoic acid self-assembled monolayer 2 3 7 8-TCDD
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Isolation, identification, and cytotoxicity of a new isobenzofuran derivative from marine Streptomyces sp. W007 被引量:1
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作者 张宏宇 谢则平 +1 位作者 娄婷婷 姜鹏 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第2期386-390,共5页
A new isobenzofuran derivative( 1) was isolated from the marine Streptomyces sp. W007 and its structure was determined through extensive spectroscopic analyses, including 1D-NMR, 2D-NMR, and ESI-MS. The absolute confi... A new isobenzofuran derivative( 1) was isolated from the marine Streptomyces sp. W007 and its structure was determined through extensive spectroscopic analyses, including 1D-NMR, 2D-NMR, and ESI-MS. The absolute configuration of compound 1 was determined by a combination of experimental analyses and comparison with reported data, including biogenetic reasoning, J-coupling analysis, NOESY, and 1 H- 1 HCOSY. Compound 1 exhibited no cytotoxicity against human cells of gastric cancer BGC-823, lung cancer A549, and breast cancer MCF7. 展开更多
关键词 marine streptomycete isobenzofuran derivative absolute configuration CYTOTOXICITY
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Watershed-based Image Segmentation with Region Merging and Edge Detection 被引量:1
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作者 Salman N H 《High Technology Letters》 EI CAS 2003年第1期58-63,共6页
The clustering technique is used to examine each pixel in the image which assigned to one of the clusters depending on the minimum distance to obtain primary classified image into different intensity regions. A waters... The clustering technique is used to examine each pixel in the image which assigned to one of the clusters depending on the minimum distance to obtain primary classified image into different intensity regions. A watershed transformation technique is then employes. This includes: gradient of the classified image, dividing the image into markers, checking the Marker Image to see if it has zero points (watershed lines). The watershed lines are then deleted in the Marker Image created by watershed algorithm. A Region Adjacency Graph (RAG) and Region Adjacency Boundary (RAB) are created between two regions from Marker Image. Finally region merging is done according to region average intensity and two edge strengths (T1, T2). The approach of the authors is tested on remote sensing and brain MR medical images. The final segmentation result is one closed boundary per actual region in the image. 展开更多
关键词 image segmentation edge detection WATERSHED K-MEANS edge strength brain images remote sensing images region adjacency graph (RAG).
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Neighborhood fusion-based hierarchical parallel feature pyramid network for object detection 被引量:3
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作者 Mo Lingfei Hu Shuming 《Journal of Southeast University(English Edition)》 EI CAS 2020年第3期252-263,共12页
In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid... In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid network(FPN)and deconvolutional single shot detector(DSSD),where the bottom layer of the feature pyramid network relies on the top layer,NFPN builds the feature pyramid network with no connections between the upper and lower layers.That is,it only fuses shallow features on similar scales.NFPN is highly portable and can be embedded in many models to further boost performance.Extensive experiments on PASCAL VOC 2007,2012,and COCO datasets demonstrate that the NFPN-based SSD without intricate tricks can exceed the DSSD model in terms of detection accuracy and inference speed,especially for small objects,e.g.,4%to 5%higher mAP(mean average precision)than SSD,and 2%to 3%higher mAP than DSSD.On VOC 2007 test set,the NFPN-based SSD with 300×300 input reaches 79.4%mAP at 34.6 frame/s,and the mAP can raise to 82.9%after using the multi-scale testing strategy. 展开更多
关键词 computer vision deep convolutional neural network object detection hierarchical parallel feature pyramid network multi-scale feature fusion
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Measuring Method for Shunt Resistance of Solar Cell
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作者 CHENTingjin WANGDongxiang 《Semiconductor Photonics and Technology》 CAS 1998年第1期62-66,共5页
Shunt resistance of solar cell must be monitored for large area solar cell manufactured with conventional process.A measuring method for the shunt resistance is derived from direct-current model.The shunt resistance o... Shunt resistance of solar cell must be monitored for large area solar cell manufactured with conventional process.A measuring method for the shunt resistance is derived from direct-current model.The shunt resistance of solar cell is obtained only by treating a part of I-V data. 展开更多
关键词 Direct-current Model Measuring Method Shunt Resistance Solar Cell
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