检索结果-内蒙古大学图书馆

作者： Ongsakul, W. Dechanupaprittha, S. Ngamroo, I. Energy Field of Study Sch. of Environ. Rsrc./Development Asian Institute of Technology Pathumthani 12120 Thailand Electrical Power Engineering Program Sirindhorn Intl. Inst. of Technology Thammasat University Pathumthani 12121 Thailand

A parallel tabu search (PTS) algorithm for solving ramp rate constrained economic dispatch (CED) problems for generating units with non-monotonically and monotonically increasing incremental cost (IC) functions is proposed. To parallelise tabu search (TS) algorithms efficiently, the neighbourhood decomposition is used to balance the computing load, whereas competitive selection is used to update the best solution reached among subneighbourhoods. The proposed PTS is implemented on a 32-processor Beowulf cluster with an Ethernet switching network on a generating unit system size in the range 10-80 units over the entire dispatch periods. With different subneighbourhood sizes, the proposed PTS compromises the experimental speedup and solution quality for the best performance. PTS is potentially viable for the online implementation of CED because of the substantial generator fuel cost savings and high speedup upper bounds.

关键词： Electric power systems

来源：评论

学校读者我要写书评

暂无评论

Chopping of Oil Palm Empty Fruit Bunch Required to Produce Compost Material

Chopping of Oil Palm Empty Fruit Bunch Required to Produce C...

引用

国际农业工程大会

作者： Hadi Suryanto Lecturer and Head Study Program of Agricultural Engineering Faculty of Agriculture Andalas University PO Box 87 Padang Indonesia.

In Indonesia, there is about 2 million ha of oil palm plantation with 25-ton/ha/year fruit bunch. Besides oil, processing of fruit bunch also produces empty bunch of about 25%. This empty bunch is usually burned at th... 详细信息

关键词： Chopping of Oil Palm Empty Fruit Bunch Required to Produce Compost Material

来源：评论

学校读者我要写书评

暂无评论

A gait adaptation scheme for biped walking robots

A gait adaptation scheme for biped walking robots

引用

International Workshop on Advanced Motion Control (AMC)

作者： O. Bebek K. Erbatur Department of Electrical Engineering and Computer Science Case Western Reserve University USA Mechatronics Program Faculty of Engineering and Natural Sciences Sabanci University Turkey

Recent years witnessed a growing interest in biped walking robots because of their advantageous use in the human environment. However, their control requires many problems to be solved because of the many degrees of freedom and nonlinearity in their dynamics. The so-called open loop walking with offline trajectory generation is one of the control approaches in the literature. There are various difficulties involved in this approach, the most important one being the difficulty in tuning the gait parameters. This paper proposes an online fuzzy adaptation scheme for one of the trajectory parameters in the offline generated walking pattern. A fuzzy identifier system, represented as a three-layer feed-forward neural network is employed to compute the parameter as a function of time in simulations. Fuzzy system parameters are adapted via back-propagation. Virtual torsional springs are attached to the trunk center of the biped. The torque generated by the springs serve as the criterion for the tuning and they help maintaining a stable and a longer walk which is necessary for the online tuning process. 3D simulation and animation techniques are employed for a 12-DOF biped robot to test the proposed adaptive method.

关键词： Legged locomotion Open loop systems Fuzzy systems Springs Humans Fuzzy neural networks Feedforward systems Neural networks Feedforward neural networks Computer networks

来源：评论

学校读者我要写书评

暂无评论

Development of an FPGA-based gate signal generator for a multilevel inverter 5

Development of an FPGA-based gate signal generator for a mul...

引用

5th IEEE International Conference on Power Electronics and Drive Systems (PEDS 2003)

作者： Salim, F Azli, NA Electrical Engineering Department Program Pengajian Diploma Universiti Teknologi Malaysia Malaysia Energy Conversion Department Faculty of Electrical Engineering Universiti Teknologi Malaysia Malaysia

ISBN: (纸本)0780378857

The application of Field programmable Gate Array (FPGA) in the development of power electronics circuits control scheme has drawn much attention lately due to its shorter design cycle, lower cost and higher density. This paper presents an FPGA-based gate signal generator for a multilevel inverter employing an online optimal PWM switching strategy to control its output voltage. FPGA is chosen for the hardware implementation of the switching strategy mainly due to its high computation speed that can ensure the accuracy of the instants that gating signals are generated. The gate signal generator has been realized by an FPGA (FLEX10K20) from Altera. The design and development of the FPGA based gate signal generator is described in detail. Results from the timing simulation using MAX+PLUSII software are given and verified by the results obtained from the FLEX10K20 output.

关键词： FPGA optimal PWM multilevel inverter

来源：评论

学校读者我要写书评

暂无评论

Virtual PQ troubleshooter

引用

IEEE Power and Energy Magazine 2003年第3期1卷 24-31页

作者： Li, Chun Xu, Wilsun Hughes, Brent Gurney, James Neilson, Bruce Electrical and Computer Engineering Department University of Alberta Canada University of Alberta Canada Revenue Metering and Distribution Standards BC Hydro Canada IEEE Cigré Study Committee 36 BC Hydro's Strategic Research and Development Program IEEE Canada

An overview is given of the development of a PQ instrument that is specifically geared to power quality troubleshooting applications. The development has benefited from recent advancement in PC-based instrumentation technology and PQ disturbance source detection methods. The resultant instrument is a virtual tool, a laptop equipped with a PCMCIA card that performs all the instrumentation functions. This strategy has enhanced the reliability and flexibility of the device and also reduced the development efforts.

关键词： Electric power systems

来源：评论

学校读者我要写书评

暂无评论

DCT and wavelet based image compression in satellite images

DCT and wavelet based image compression in satellite images

引用

International Conference on Recent Advances in Space Technologies, RAST 2003

作者： Hacihaliloglul, Llker Karta, Mesut Satellite Communication and Remote Sensing Graduate Program Advanced Technologies in Engineering Informatics Institute Istanbul Technical University Maslak Istanbul34469 Turkey Electronic and Communication Department Faculty of Electrical and Electronic Engineering Istanbul Technical University Maslak Istanbul34469 Turkey

ISBN: (纸本)0780381424

Synthetic aperture radar (SAR) and SPOT images are becoming increasingly important and abundant in a variety of remote sensing and tactical applications. Thus, there is a strong interest in developing data encoding and decoding algorithms that can obtain higher compression ratios while keeping image quality to an acceptable level. This study aims to compare most of the well-known compression techniques namely discrete cosine transform and discrete wavelet transform. It investigates RADARSAT and SPOT images of different regions of different characteristics. RADARSAT-I fine and standard beam mode images of the different regions in Istanbul are used to test the performance of the compression algorithms. The regions, which have been investigated, were sea areas, forest areas, built environment - residential and industrial areas which define different patterns of urban land use. The studies showed that homogeneous areas like forest and sea gave better compression results compared to heterogeneous areas like industrial and environmental. The second purpose of this study is to compare the two compression algorithms. The discrete wavelet based algorithm gave much better results compared to the discrete cosine transform based algorithm. The results changed according to the quantization process and the transform coding algorithm. © 2003 IEEE.

关键词： Discrete wavelet transforms

来源：评论

学校读者我要写书评

暂无评论

Development of an FPGA-based gate signal generator for a multilevel inverter

Development of an FPGA-based gate signal generator for a mul...

引用

International Conference on Power Electronics and Drive Systems (PEDS)

作者： F. Salim N.A. Azli Electrical Engineering Department Program Pengajian Diploma Universiti Teknologi Malaysia Malaysia Energy Conversion Department Faculty of Electrical Engineering Universiti Teknologi Malaysia Malaysia

The application of field programmable gate array (FPGA) in the development of power electronics circuits control scheme has drawn much attention lately due to its shorter design cycle, lower cost and higher density. This paper presents an FPGA-based gate signal generator for a multilevel inverter employing an online optimal PVVM switching strategy to control its output voltage. FPGA is chosen for the hardware implementation of the switching strategy mainly due to its high computation speed that can ensure the accuracy of the instants that gating signals are generated. The gate signal generator has been realized by an FPGA (FLEX10K20) from Altera. The design and development of the FPGA based gate signal generator is described in detail. Results from the timing simulation using MAX+PLUSII software are given and verified by the results obtained from the FLEX10K20 output.

关键词： Signal generators Inverters Field programmable gate arrays Power electronics Circuits Costs Optimal control Voltage control Hardware Signal design

来源：评论

学校读者我要写书评

暂无评论

An HVDC-based controller design for stabilization of frequency oscillation

An HVDC-based controller design for stabilization of frequen...

引用

IEEE International Symposium on Circuits and Systems (ISCAS)

作者： S. Dechanupaprittha A. Patanapakdee L. Ngamroo Electrical Power Engineering Program Sirindhorn International Institute of Technology Thammasat University Thailand Mechanical Engineering Department Faculty of Engineering Sripatum University Bangkok Thailand

In this paper, a new controller design for a high-voltage direct current (HVDC) system subjected to frequency oscillation stabilization is proposed. The technique of overlapping decompositions is used to obtain the design subsystem embedded with the inter-area oscillation mode. The designed controller has the structure of a second-order lead/lag compensator. Automatically, the parameters of the controller are tuned based on a tabu search (TS) algorithm. The designed controller is installed in a three-area longitudinal interconnected power system. Consequently, the simulation results are carried out to illustrate the effectiveness of the designed controller.

关键词： Frequency Power system interconnection HVDC transmission Automatic control Power system modeling Control systems Power system stability Power system simulation Energy exchange Damping

来源：评论

学校读者我要写书评

暂无评论

Ant colony search algorithm for unit commitment

Ant colony search algorithm for unit commitment

引用

IEEE International Conference on Industrial Technology (ICIT)

作者： T. Sum-im W. Ongsakul Department of Electrical Engineering Faculty of Engineering Srinakharinwirot University Thailand Energy Field of Study School of Environment Resources and Development Asian Institute of Technology Pathum Thani Thailand

In this paper, the ant colony search algorithm (ACSA) is proposed to solve the thermal unit commitment problem. ACSA is a new cooperative agents approach, which is inspired by the observation of the behaviors of real ant colonies on the topic of ant trial formation and foraging methods. In the ACSA, a set of cooperating agents called "ants" cooperates to find good solution for unit commitment problem of thermal units. The merits of ACSA are parallel search and optimization capabilities. The problem is decomposed in two sub-problems. The unit commitment sub-problem is solved by the ant colony search algorithm method and the economic dispatch sub-problem is solved by the lambda-iteration method. The unit commitment problem is formulated as the minimization of the performance index, which is the sum of objectives (fuel cost, start-up cost) and some constraints (power balance, generation limits, spinning reserve, minimum up time and minimum down time). This proposed approach is tested and compared to conventional Lagrangian relaxation (LR), genetic algorithm (GA), evolutionary programming (EP), Lagrangian relaxation and genetic algorithm (LRGA) on the 10 unit system.

关键词： Costs Lagrangian functions Genetic algorithms Ant colony optimization Power generation economics Fuel economy Performance analysis Power generation Spinning System testing

来源：评论

学校读者我要写书评

暂无评论

Image quality and noise evaluation

Image quality and noise evaluation

引用

International Symposium on Signal Processing and Its Applications (ISSPA)

作者： C.Y. Fah O.M. Rijal N.M. Noor Faculty of Engineering Multimedia University Cyberjaya Selangor Darul Ehsan Malaysia Institute of Mathematical Science Faculty of Science University Malaya Kuala Lumpur Malaysia Electrical Engineering Course Diploma Program Universiti Teknologi Malaysia Kuala Lumpur Malaysia

The definition of a 'good image' is subjective and depends on the requirements of a given application Gonzalez, R. C., Woods, R. E. (1992). For example, image quality is highly connected to the process of image sampling and data compression. Noise can be generated and added in during both processes, plus it can also be generated if further processing is imposed on the image such as brightness enhancement or contrast stretch. The common practice is to evaluate the quality of the image visually. This is a subjective process since noise cannot be measured accurately Parker, J. R. (1997). In this paper, we propose using the coefficient of determination for the unreplicated linear functional relationship (ULFR) model, namely R/sup 2//sub F/ as a measure of the similarity between two images which in turn may be used as a definition for image quality Dolby G. R. (1976), Fuller, W. A. (1987). The derivation of R/sup 2//sub F/ is briefly reviewed. This study shows that the proposed similarity measure performs better than particular similarity measures Dietrich et al. (2002).

关键词： Image quality Noise measurement Performance evaluation Data compression Particle measurements Filtering Digital images Image analysis NIST Image sampling

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：