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新的体系结构创造了新一代的逻辑分析器——TLA700型系列产品的异步数字附加取样结构是硬件定时检测技术的新典范
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《今日电子》 1997年第2期78-80,142,共4页
传统的逻辑分析仪结构已不能满足市场的需求。当处理器的速度超过100MHz并出现了先进的逻辑电路时,现有的100MS/s(每秒兆样值)逻辑分析器已跟不上时代的前进步伐。不仅如此,快速移动的数字信号还会感受串扰和反射等模拟效应。100MHz的... 传统的逻辑分析仪结构已不能满足市场的需求。当处理器的速度超过100MHz并出现了先进的逻辑电路时,现有的100MS/s(每秒兆样值)逻辑分析器已跟不上时代的前进步伐。不仅如此,快速移动的数字信号还会感受串扰和反射等模拟效应。100MHz的常规逻辑分析器只能提供10ns的定时分辨率,因此无法测出高速毛刺和微小的定时问题。 逻辑分析器的制造厂商一直设法改进现有的产品。尽管如此,逻辑分析器仍不能满足市场的需要。他们曾试图以减少通道的方法而获得较高的捕获速率和较大的存储量。 展开更多
关键词 逻辑分析仪 自理器 异步数字式 取样结构
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新一代SHARC结构的DSP-ADSP21160 被引量:1
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作者 王大鸣 丁志强 黄慧群 《微处理机》 1999年第4期13-15,共3页
介绍一种 AD公司新一代超级哈佛结构的 DSP-ADSP2 1 1 60的应用特点、主要性能及芯片内部的系统结构和功能框图 ,并简要介绍以 ADSP2 1 1
关键词 DSP 数字信号自理器 超级哈佛结构 ADSP21160
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MICROPROCESSOR BASED MODEL FOLLOWING ADAPTIVE CONTROL SYSTEM FOR CSIM DRIVES
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作者 张春明 左敦稳 王珉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期40+35-39,共6页
A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is ... A model following adaptive control system for CSIM is presented in this paper. A dynamic mathematical model of slip control based system is obtained. With the help of model reducing technique, full order model is reduced to simplify the design without degrading much of the performance. Model following adaptive control laws in discrete form are derived. These laws satisfy the hyperstability condition for taking care of the load and machine parameter changes of the drive. A microprocessor 8098 is used to develop the speed controller. The implementation of the control system uses only available variables of the reference model and the controlled plant. Experimental results are given to demonstrate the good performance of the system. 展开更多
关键词 induction motors frequency converters microprocessors adaptive control model following
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Design and dynamic simulation of hydraulic system of a new automatic transmission 被引量:15
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作者 王书翰 徐向阳 +3 位作者 刘艳芳 戴振坤 TEN BERGE P 曲巍 《Journal of Central South University》 SCIE EI CAS 2009年第4期697-701,共5页
A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic syste... A new hydraulic system of a novel automatic transmission (AT) was designed. The dimension and structure of valves and cylinders were designed by theoretical calculation. The dynamic simulation model of hydraulic system of AT was established by ITI-SimulationX. Simulation results and theoretical design results were compared to confirm the simulation model. Based on the confirmed simulation model, the simulation results of pressure and flow of the hydraulic system were analyzed. The dynamic simulation method is very helpful for designing and analyzing the performance of hydraulic system and further optimization design. The theoretical design method and dynamic simulation model are feasible for the real industrial applications. The research results can be used in hydraulic system design and optimization. 展开更多
关键词 automatic transmission hydraulic system dynamic simulation
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Study on Real-time Look-ahead and Adaptive Parametric Curve Interpolator 被引量:2
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作者 郭伟 杜道山 +1 位作者 徐荣珍 李从心 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第3期388-393,共6页
The principle of real-time look-ahead was introduced and analysed. An adaptive parametric curve interpolator with a real-time look-ahead function was developed for non-uniform rational B-spline (NURBS) curves interpol... The principle of real-time look-ahead was introduced and analysed. An adaptive parametric curve interpolator with a real-time look-ahead function was developed for non-uniform rational B-spline (NURBS) curves interpolation, which considering the maximum acceleration/deceleration of the machine tool. In order to deal with the acceleration/deceleration around the feedrate sensitive corners, the look-ahead function was designed and illustrated. It can detect and adjust the feedrate adaptively. With the help of real-time look-ahead, the acceleration/deceleration can be limited to the range of the machine tool capacity. Thus, feedrate fluctuation is reduced. A NURBS curve interpolation experiment was provided to verify the feasibility and advantages of the proposed interpolator with a real-time look-ahead function. 展开更多
关键词 adaptive interpolator LOOK-AHEAD non-uniform rational B-spline curves feedrate sensitive corner chord error
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A closed-loop particle swarm optimizer for multivariable process controller design 被引量:2
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作者 Kai HAN Jun ZHAO +1 位作者 Zu-hua XU Ji-xin QIAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第8期1050-1060,共11页
Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms (EAs) since it can be formulated as an optimization problem. A closed-loop... Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms (EAs) since it can be formulated as an optimization problem. A closed-loop particle swarm optimization (CLPSO) algorithm is proposed by mapping PSO elements into the closed-loop system based on control theories. At each time step, a proportional integral (PI) controller is used to calculate an updated inertia weight for each particle in swarms from its last fitness. With this modification, limitations caused by a uniform inertia weight for the whole population are avoided, and the particles have enough diversity. After the effectiveness, efficiency and robustness are tested by benchmark functions, CLPSO is applied to design a multivariable proportional-integral-derivative (PID) controller for a solvent dehydration tower in a chemical plant and has improved its performances. 展开更多
关键词 Multivariable process control Proportional-integral-derivative (PID) control Model predictive control (MPC) Particle swarm optimization (PSO) Closed-loop system
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UPF based autonomous navigation scheme for deep space probe 被引量:8
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作者 Li Peng Cui Hutao Cui Pingyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期529-536,共8页
The autonomous "celestial navigation scheme" for deep space probe departing from the earth and the autonomous "optical navigation scheme" for encountering object celestial body are presented. Then,... The autonomous "celestial navigation scheme" for deep space probe departing from the earth and the autonomous "optical navigation scheme" for encountering object celestial body are presented. Then, aiming at the conditions that large initial estimation errors and non-Gaussian distribution of state or measurement errors may exist in orbit determination process of the two phases, UPF (unscented particle filter) is introduced into the navigation schemes. By tackling nonlinear and non-Gaussian problems, UPF overcomes the accuracy influence brought by the traditional EKF (extended Kalman filter), UKF (unscented Kalman filter), and PF (particle filter) schemes in approximate treatment to nonlinear and non-Gaussian state model and measurement model. The numerical simulations demonstrate the feasibility and higher accuracy of the UPF navigation scheme. 展开更多
关键词 control and navigation technology of aircraft nonlinear and non-Gaussian unscented particle filter autonomous orbit determination celestial navigation optical navigation.
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Suboptimal reliable guaranteed cost control for continuous-time systems with multi-criterion constraints 被引量:1
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作者 Deng-feng ZHANG Hong-ye SU +1 位作者 Jian CHU Zhi-quan WANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第8期1024-1033,共10页
The suboptimal reliable guaranteed cost control (RGCC) with multi-criterion constraints is investigated for a class of uncertain continuous-time systems with sensor faults. A fauk model in sensors, which considers o... The suboptimal reliable guaranteed cost control (RGCC) with multi-criterion constraints is investigated for a class of uncertain continuous-time systems with sensor faults. A fauk model in sensors, which considers outage or partial degradation of sensors, is adopted. The influence of the disturbance on the quadratic stability of the closed-loop systems is analyzed. The reliable state-feedback controller is developed by a linear matrix inequalities (LMIs) approach, to minimize the upper bound of a quadratic cost fimction under the conditions that all the closed-loop poles be placed in a specified disk, and that the prescribed level of H∞ disturbance attenuation and the upper bound constraints of control inputs' magnitudes be guaranteed. Thus, with the above muki-criterion constraints, the resulting closed-loop system can provide satisfactory stability, transient property, a disturbance rejection level and minimized quadratic cost performance despite possible sensor faults. 展开更多
关键词 Sensor faults Multi-criterion constraints Reliable guaranteed cost control (RGCC) Linear matrix inequality (LMI)
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WORD SENSE DISAMBIGUATION BASED ON IMPROVED BAYESIAN CLASSIFIERS 被引量:1
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作者 Liu Ting Lu Zhimao Li Sheng 《Journal of Electronics(China)》 2006年第3期394-398,共5页
Word Sense Disambiguation (WSD) is to decide the sense of an ambiguous word on particular context. Most of current studies on WSD only use several ambiguous words as test samples, thus leads to some limitation in prac... Word Sense Disambiguation (WSD) is to decide the sense of an ambiguous word on particular context. Most of current studies on WSD only use several ambiguous words as test samples, thus leads to some limitation in practical application. In this paper, we perform WSD study based on large scale real-world corpus using two unsupervised learning algorithms based on ±n-improved Bayesian model and Dependency Grammar (DG)-improved Bayesian model. ±n-improved classifiers reduce the window size of context of ambiguous words with close-distance feature extraction method, and decrease the jamming of useless features, thus obviously improve the accuracy, reaching 83.18% (in open test). DG-improved classifier can more effectively conquer the noise effect existing in Naive-Bayesian classifier. Experimental results show that this approach does better on Chinese WSD, and the open test achieved an accuracy of 86.27%. 展开更多
关键词 Word Sense Disambiguation (WSD) Natural Language Processing (NLP) Unsupervised learning algorithm Dependency Grammar (DG) Bayesian classifier
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Adaptable Processing: Stage Development
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作者 Dumitru Todoroi 《Journal of Literature and Art Studies》 2013年第5期305-311,共7页
The development and evolution of Microsoft Office and Microsoft Windows shells are based in general on the special methodology of software creation and implementation such as macros, subroutine, custom commands, and s... The development and evolution of Microsoft Office and Microsoft Windows shells are based in general on the special methodology of software creation and implementation such as macros, subroutine, custom commands, and specialized features. Microsoft Office for Mac has for long been criticized for its lack of support of Unicode and BiDi languages, notably Arabic and Hebrew. This has not changed in the Office 2008 version. Microsoft Office 2010 (also called Office 2010 and Office 14) is the current version of the Microsoft Office productivity suite for Microsoft Windows, and the successor to Microsoft Office 2007. With Office 2010, users are in control, getting things done and producing amazing results however and wherever they work best. Ms Office 2010 is the last version of Microsoft Office with support for Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008 due to Office 2013 requiring Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, or Windows RT. Adaptive hardware (Ugurdag, 2006) reflects the capability of a system to maintain or improve its performance in the context of internal or external changes. Adaptation at hardware levels increases the system capabilities beyond what is possible with software-only solutions. Algorithms, techniques, and their implementation in hardware are developed over a diverse variety of applications. The methodology of the On-Off-Line adaptable processors (Todoroi & Micusha, 2012) support development of adaptable software and hardware. Automatic creation of the Off-Line adaptable processors are proved. Development of the On-Line and On-Off-Line adaptable processors based on Off-Line processing creation method is proposed (Todoroi, Micu^a, & Todoroi, 2009; Todoroi, 2008a, 2008b) 展开更多
关键词 ADAPTABILITY ADAPTIVE PROCESSOR LANGUAGE adaptable processor adaptive hardware adaptable software
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Space discriminative function for microphone array robust speech recognition
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作者 赵贤宇 Ou Zhijian Wang Zuoying 《High Technology Letters》 EI CAS 2005年第4期351-354,共4页
Based on W-disjoint orthogonality of speech mixtures, a space d,scnmlnative tunetlon was proposer1 to enumerate and localize competing speakers in the surrounding environments. Then, a Wiener-like postfiherer was deve... Based on W-disjoint orthogonality of speech mixtures, a space d,scnmlnative tunetlon was proposer1 to enumerate and localize competing speakers in the surrounding environments. Then, a Wiener-like postfiherer was developed to adaptively suppress interferences. Experimental results with a hands-free speech recognizer under various SNR and competing speakers settings show that nearly 69 % error reduction can be obtained with a two-channel small aperture microphone array against the conventional single microphone baseline system. Comparisons were made against traditional delay-and-sum and Griffiths-Jim adaptive beamforming techniques to further assess the effectiveness of this method. 展开更多
关键词 speech recognition array signal processing microphone array source localization adaptive filtering
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Configuration information acquisition and matching in self-reconfiguring process of modular self-reconfigurable robots 被引量:1
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作者 任宗伟 《High Technology Letters》 EI CAS 2008年第4期411-417,共7页
Configuration information acquisition and matching are two important steps in the self-reconfiguring process of self-reconfigurable robots. The process of configuration information acquisition was introduced, and a se... Configuration information acquisition and matching are two important steps in the self-reconfiguring process of self-reconfigurable robots. The process of configuration information acquisition was introduced, and a self-reconfiguring configuration matching strategy based on graded optimization mechanism was proposed. The first-grade optimization was to search common connection between matching scheme and goal configuration. The second-grade optimization, whose object function was constructed in terms of configuration connectivity, was to search connnon topology according to the results of the first-grade optimization. The entire process of configuration information acquisition and matching was verified by an experiment and genetic algorithm (GA). The result shows the accuracy of the configuration information acquisition and the effectiveness of the configuration matching method. 展开更多
关键词 self-reconfigurable robot genetic algorithm (GA) information acquisition configuration matching graded optimization.
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Improved Real-time Implementation of Adaptive Gassian Mixture Model-based Object Detection Algorithm for Fixed-point DSP Processors 被引量:2
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作者 Byung-eun LEE Thanh-binh NGUYEN Sun-tae CHUNG 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期116-120,共5页
Foreground moving object detection is an important process in various computer vision applications such as intelligent visual surveillance, HCI, object-based video compression, etc. One of the most successful moving o... Foreground moving object detection is an important process in various computer vision applications such as intelligent visual surveillance, HCI, object-based video compression, etc. One of the most successful moving object detection algorithms is based on Adaptive Gaussian Mixture Model (AGMM). Although ACMM-hased object detection shows very good performance with respect to object detection accuracy, AGMM is very complex model requiring lots of floatingpoint arithmetic so that it should pay for expensive computational cost. Thus, direct implementation of the AGMM-based object detection for embedded DSPs without floating-point arithmetic HW support cannot satisfy the real-time processing requirement. This paper presents a novel rcal-time implementation of adaptive Gaussian mixture model-based moving object detection algorithm for fixed-point DSPs. In the proposed implementation, in addition to changes of data types into fixed-point ones, magnification of the Gaussian distribution technique is introduced so that the integer and fixed-point arithmetic can be easily and consistently utilized instead of real nmnher and floatingpoint arithmetic in processing of AGMM algorithm. Experimental results shows that the proposed implementation have a high potential in real-time applications. 展开更多
关键词 background modeling real-time computing object de-tection
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Modeling TCP performance with proxy and ARQ
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作者 金彦亮 杨宇航 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期164-171,共8页
TCP/IP is a next generation key technology in the wireless communication network where the different characteristics of wireless and wired links result in performance degradation. We can use the proxy and automatic re... TCP/IP is a next generation key technology in the wireless communication network where the different characteristics of wireless and wired links result in performance degradation. We can use the proxy and automatic repeat request (ARQ) schemes to deal with this problem. In this work, we investigate the TCP performance over proxy and ARQ in the wireless network. Our analysis results showed that using the proxy can result in lower transfer latency and higher throughput and that ARQ can decrease the loss rate of wireless link and improve the performance with little additional latency. The analytical results were validated against simulations using the NS-2 with some more realistic parameters. 展开更多
关键词 TCP performance Wireless communication PROXY ARQ
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A New Self-assembly Metal CMG Discriminator by Multi-exposure LiGA Like Process and Sacrificial Layer Process 被引量:1
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作者 张卫平 陈文元 +2 位作者 赵小林 丁桂甫 李胜勇 《Journal of Donghua University(English Edition)》 EI CAS 2005年第4期91-93,共3页
The counter-meshing gears (CMG) discriminator is a mechanically coded lock, which is used to prevent the occurrence of High Consequence Events. This paper advanced a new kind of self-assembly metal CMG discriminator... The counter-meshing gears (CMG) discriminator is a mechanically coded lock, which is used to prevent the occurrence of High Consequence Events. This paper advanced a new kind of self-assembly metal CMG discriminator based on multi-exposure LiGA like process and sacrificial layer process. The new CMG discriminator has the following characters except low cost: 1) it has only discrimination teeth sections; 2) the thickness of each gear layer exceeds one hundred micrometers; 3) it is axially driven by a separate dectronic magnetic micromotor directly; 4) its CMG is made of metal and is batch fabricated in the assembled state; 5) it is prevented from rotating in the opposite direction by pawl/ratchet wheel mechanism; 6) it has simpler structure. This device has better strength and reliability in abnormal environment compared to the existing surface micro machining (SMM) discriminator. 展开更多
关键词 Counter-meshing gears (CMG) discriminator multi-exposure LiGA like process sacrificial layer process.
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Pyramidal Edge Detection Method Based on AWFM Filtering and Fuzzy Linking Model
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作者 王志刚 WangDong 《High Technology Letters》 EI CAS 2002年第1期26-31,共6页
A novel multiresolution pyramidal edge detector, based on adaptive weighted fuzzy mean(AWFM)filtering and fuzzy linking model, is presented in this paper. The algorithm first constructs a pyramidal structure by repeti... A novel multiresolution pyramidal edge detector, based on adaptive weighted fuzzy mean(AWFM)filtering and fuzzy linking model, is presented in this paper. The algorithm first constructs a pyramidal structure by repetitive AWFM filtering and subsampling of original image. Then it utilizes multiple heuristic linking criteria between the edge nodes of two adjacent levels and considers the linkage as a fuzzy model, which is trained offline. Through this fuzzy linking model, the boundaries detected at coarse resolution are propagated and refined to the bottom level from the coarse-to fine edge detection. The validation experiment results demonstrate that the proposed approach has superior performance compared with standard fixed resolution detector andprevious multiresolution approach, especially in impulse noise environment. 展开更多
关键词 Edge detector Pyramidal structure Adaptive weight fuzzy mean filter Fuzzy modeling Impulse noise
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Construction of unsupervised sentiment classifier on idioms resources 被引量:2
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作者 谢松县 王挺 《Journal of Central South University》 SCIE EI CAS 2014年第4期1376-1384,共9页
Sentiment analysis is the computational study of how opinions, attitudes, emotions, and perspectives are expressed in language, and has been the important task of natural language processing. Sentiment analysis is hig... Sentiment analysis is the computational study of how opinions, attitudes, emotions, and perspectives are expressed in language, and has been the important task of natural language processing. Sentiment analysis is highly valuable for both research and practical applications. The focuses were put on the difficulties in the construction of sentiment classifiers which normally need tremendous labeled domain training data, and a novel unsupervised framework was proposed to make use of the Chinese idiom resources to develop a general sentiment classifier. Furthermore, the domain adaption of general sentiment classifier was improved by taking the general classifier as the base of a self-training procedure to get a domain self-training sentiment classifier. To validate the effect of the unsupervised framework, several experiments were carried out on publicly available Chinese online reviews dataset. The experiments show that the proposed framework is effective and achieves encouraging results. Specifically, the general classifier outperforms two baselines(a Na?ve 50% baseline and a cross-domain classifier), and the bootstrapping self-training classifier approximates the upper bound domain-specific classifier with the lowest accuracy of 81.5%, but the performance is more stable and the framework needs no labeled training dataset. 展开更多
关键词 sentiment analysis sentiment classification bootstrapping idioms general classifier domain-specific classifier
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Automatic Migration of a Software Task to Hardware Component in MPSoC Systems
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作者 Kamel Smiri Abdelhafidh Ben Fadhel +1 位作者 Abderrazak Jemai Ahmed Chiheb Ammari 《Computer Technology and Application》 2011年第12期931-938,共8页
The authors will focus on the study of the design of Multiprocessor Systems on Chip (MPSoC), specifically in the context of improving the performance of applications located on the MPSoC architecture. The objective ... The authors will focus on the study of the design of Multiprocessor Systems on Chip (MPSoC), specifically in the context of improving the performance of applications located on the MPSoC architecture. The objective of this research is to study the problems of transition from a pure software implementation for an embodiment admitting one or more hardware components and to develop a methodology for automatic generation of migration of a software task into a hardware component in MPSoC. The transformation of a software task into a hardware task led to many changes, hardware part (connection, the requirement of an interrupt controller...), software part (at least one task, I/O (I/O), synchronization...) and an architectural point of view, the remarkable aspects of data storage. The experiment is done on the MJPEG decoder to illustrate the effectiveness of the authors' tool for automatic generation of migration. 展开更多
关键词 CO-DESIGN decoder motion-JPEG transaction accurate automatic generation material component.
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Research on Influence of Micro Structure on Residual Oil Distribution
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作者 Xu Xin Cao Ying Li Lei 《International Journal of Technology Management》 2015年第2期127-129,共3页
Researching residual oil distribution not only is a difficulty in the world, but also is the pioneering research subject in different fields such as geology, physical geography and reservoir engineering. The modem geo... Researching residual oil distribution not only is a difficulty in the world, but also is the pioneering research subject in different fields such as geology, physical geography and reservoir engineering. The modem geology technique, well logging technology and reservoir engineering technique develops rapidly, which provides favorable conditions for researching residual oil distribution. 展开更多
关键词 detailed reservoir description residual oil distribution sedimentary characteristics heterogenous
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Semi-physical simulation of AUV pipeline tracking 被引量:1
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作者 李晔 庞永杰 +1 位作者 张磊 张鸿皓 《Journal of Central South University》 SCIE EI CAS 2012年第9期2468-2476,共9页
Before the task of autonomous underwater vehicle(AUV) was implemented actually,its semi-physical simulation system of pipeline tracking had been designed.This semi-physical simulation system was used to test the softw... Before the task of autonomous underwater vehicle(AUV) was implemented actually,its semi-physical simulation system of pipeline tracking had been designed.This semi-physical simulation system was used to test the software logic,hardware architecture,data interface and reliability of the control system.To implement this system,the whole system plan,including interface computer and the methods of pipeline tracking,was described.Compared to numerical simulation,the semi-physical simulation was used to test the real software and hardware more veritably.In the semi-physical simulation system,tracking experiments of both straight lines and polygonal lines were carried out,considering the influence of ocean current and the situation of buried pipeline.The experimental results indicate that the AUV can do pipeline tracking task,when angles of pipeline are 15°,30°,45° and 60°.In the ocean current of 2 knots,AUV could track buried pipeline. 展开更多
关键词 autonomous underwater vehicle semi-physical simulation underwater pipeline tracking underwater sensor simulation underwater optical vision
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