检索结果-内蒙古大学图书馆

IAENG International Journal of Computer Science 2021年第3期48卷 1-7页

作者： Velez-Ramirez, Juan S. Giraldo, Eduardo Graduated student The master on Electrical Engineering program Universidad Tecnologica de Pereira Pereira Colombia Professor at the Department of Electrical Engineering Universidad Tecnologica de Pereira Research Group in Automatic Control Pereira Colombia

In this work, a method for hierarchical hybrid linear-nonlinear microgrid control is proposed based on nonlinear primary control and linear secondary control. The nonlinear controller is an Extended Feedback Linearization method, and the linear controller is a PID structure. The proposed method is evaluated in several scenarios to validate its performance to disturbances and island operation mode. To this end, three units of distributed generation are included: Photo-Voltaic Energy Sources, Energy Storage Systems, and Small-Hydro-Power Sources. The results are simulated over a DC microgrid that contains three different distributed generation units with disturbances and island operation mode. As a result, the proposed approach's robustness is validated for several cases, where the advantage of a hierarchical linear-nonlinear structure is shown. © 2021. All Rights Reserved.

关键词： Controllers

来源：评论

学校读者我要写书评

暂无评论

Smart inverter arc fault protection for photovoltaic power systems 17

Smart inverter arc fault protection for photovoltaic power s...

引用

17th IEEE International Conference on Environment and electrical engineering and 2017 1st IEEE Industrial and Commercial Power Systems Europe, EEEIC / I and CPS Europe 2017

作者： Vidales, B. Weber, S. Schweitzer, R. Torres, D. Madrigal, M. Vandoeuvre les Nancy54506 France Graduated Program of Research in Electrical Engineering Technologic of Mexico - Technological Institute of Morelia Morelia Mexico

ISBN: (纸本)9781538639160

In this work is presented a study of the influence that basic components present in photovoltaic installations, have in conventional Arc Fault (AF) protection systems, one of this components is the DC/AC Converter and MPPT tracking system which both work under the command of a PWM switching control strategy. With a deeper analysis of this type of components is possible to develop an approach that improve the actual efficiency of arc fault prevention systems. The possibility of preventing arc faults by detecting a voltage drop and modifying converters control is study and disputed its in this work. This is possible due to the fact that the DC/AC converters has a direct impact in the harmonic content of current and voltage signals conventionally employed in Arc Fault Detection Devices (AFDD), a comparative analysis of simulation results between both real and ideal schematic validate the statement above. © 2017 IEEE.

关键词： Solar panels

来源：评论

学校读者我要写书评

暂无评论

A New Fuzzy Logic Application To Search the Optimal Step Size For NLMS Beamforming

A New Fuzzy Logic Application To Search the Optimal Step Siz...

引用

International Conference on Telecommunications and Signal Processing

作者： Walter Orozco-Tupacyupanqui Hector Perez-Meana Mariko Nakano-Miyatake Graduated PhD program in Communication and Electronic Engineering National Polytechnic Institute Graduate studies and Research section of The Mechanical and Electrical Engineering School National Polytechnic Institute

ISBN: (纸本)9781479984992

This paper proposes a new application based on fuzzy logic to search the optimal Step Size of the Normalized Least Mean Square (NLMS) algorithm for beamforming systems. The searching of the step size depends on the fuzzy inference results of an estimation of the final value of the cost function (J_E) instead of using its instantaneous value. The update of the step-size is performed outside of the adaptive algorithm and given it feedback by the fuzzy inference system;therefore the step-size is still fixed for the NLMS algorithm but variable for the complete searching scheme. Simulation experimental results show that a useful approximation of the optimal step-size can be obtained for different conditions of signal-to-noise plus interference ratios (SINR) and the minimization of the mean square error for the adaptive beamforming algorithm is also achieved.

关键词： Adaptive linear array Communication systems Fuzzy inference systems Normalized least mean square (NLMS) algorithm Smart antennas

来源：评论

学校读者我要写书评

暂无评论

A fair and efficient bandwidth allocation algorithm for high-speed local area networks

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1996年第5期79卷 66-75页

作者： Saito, T Aida, H Kim, B Aoki, T Faculty of Engineering the University of Tokyo Tokyo Japan 113 Byung-suk Kim:graduated in 1991 from the Department of Electrical Engineering Seoul University Korea and received his Master's degree in 1994 from the University of Tokyo where he is currently in the doctoral program. He is engaged in research on access control in ultrahigh-speed LAN.

With the advent of broadband integrated services digital network (B-ISDN), there is the increasing need for high-speed multimedia systems also in the area of local area networks (LANs). It is obvious that the conventional systems such as CSMA/CD or token ring cannot cope with those requirements. At present, several new access control methods are proposed for slotted ring (or bus) LANs suited to transmission rates above 155 Mbps. This paper reviews the characteristics of those methods in a systematic way and proposes a new access control method called distributed reset algorithm (DRA). DRA can provide high throughput while maintaining the almost strict access fairness by using a new control called ''access bit control'' in addition to the already known window control.

关键词： high-speed LAN slotted ring ATMR metaring method FECCA

来源：评论

学校读者我要写书评

暂无评论

FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

引用

GROUND WATER MONITORING AND REMEDIATION 1991年第2期11卷 107-120页

作者： OSTENDORF, DW LEACH, LE HINLEIN, ES XIE, YF 1 David W. Ostendorf is an associate professor in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Dr. Ostendorf is a registered professional engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Water Well Association.2 Lowell E. Leach is an environmental engineer with the Robert S. Kerr Environmental Research Laboratory of the U.S. Environmental Protection Agency (RS Kerr Environmental Research Laboratory U.S. EPA P.O. Box 1198 Ada OK74820). Leach received his B.S. ingeological engineering at the University of Oklahoma in 1959 and has been a registered professional engineer in Oklahoma since 1966. With 29 years of experience in field applications of geological engineering he is responsible for developing methodology for sampling ground water and subsurface materials for the Robert S. Kerr Environmental Research Laboratory.3 Erich S. Hinlein is a research assistant in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include ground water pollution hazardous waste site investigation and transport processes in unconfined aquifers. Hinlein graduated with a B.S. in electrical and computer engineering from the University of Massachusetts at Amherst in May 1985 and entered the Environmental Engineering Master's Degree Program in January 1989.4 Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil E

Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured field extrusion of core barrels into pint-size Mason jars, while the second consisted of laboratory partitioning of intact stainless steel core sleeves. The barrel extrusion procedure involved jar headspace sampling in a nitrogen-filled glove box, which delineated the 0.7m thick residually contaminated interval for subsequent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were subjected to methylene chloride extraction and gas chromatographic analysis to compare their aviation gasoline content. The barrel extrusion sampling method yielded a vertical profile with 0.10m resolution over an essentially continuous 5.0m interval from the ground surface to the water table. The sleeve segment alternative yielded a more resolved 0.03m vertical profile over a shorter 0.8m interval through the capillary fringe. The two methods delivered precise estimates of the vertically integrated mass of aviation gasoline at a given horizontal location, and a consistent view of the vertical profile as well. In the latter regard, a 0.2m thick lens of maximum contamination was found in the center of the capillary fringe, where moisture filled all voids smaller than the mean pore size. The maximum peak was resolved by the core sleeve data, but was partially obscured by the barrel extrusion observations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the absence of sleeve partitions.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Sentiment Analysis of Hashtag Activism on Social Media Twitter

Sentiment Analysis of Hashtag Activism on Social Media Twitt...

引用

Computer Science, Information Technology and engineering (ICCoSITE), International Conference on

作者： Sidharta Sidharta Yaya Heryadi Lukas Lukas Wayan Suparta Yulyani Arifin Computer Science Department BINUS Graduated Program Computer Science Bina Nusantara University Jakarta Indonesia Cognitive Engineering Research Group (CERG) Universitas Katolik Indonesia Atma Jaya Jakarta Indonesia Department of Electrical Engineering Faculty of Industrial Technology Institut Teknologi Nasional Yogyakarta Yogyakarta Indonesia

Currently, the performance of the police in Indonesia is often in the spotlight of the public with cases that occur, both on a national and regional scale, including personal experiences who also feel disappointed with the performance of the police. The cases, such as the rape of three children by a biological father in East Luwu, and the barrage of other cases that have occurred, in their handling have left the public disappointed, giving rise to the hashtag percumlaporpolisi on social media, especially on twitter. This hashtag became trending and was widely responded to by the public. Using free hashtag keywords, tweet data is collected using Twitter’s API for sentiment analysis. The datasets obtained from the crawling results is the latest data with a total of 100 datasets. This study applies the naïve bayes algorithm using textblob which aims to determine the value of polarity and subjectivity. From the results of the analysis carried out, the words that appear most often are useless police, police chief, and policeman. While the results of the sentiment analysis that has been carried out are 40 percent positive sentiment, 40 percent are neutral sentiment and 10 percent are negative sentiment from the hashtags used. From these results, according to the keywords used, the percentage of negative sentiment should be greater than positive and neutral sentiment. It is necessary to conduct a more in-depth study related to the model used in the next research.

关键词： Computer science Sentiment analysis Pediatrics Law enforcement Social networking (online) Blogs Biology

来源：评论

学校读者我要写书评

暂无评论

Measurement of refractive index distribution of optical waveguides by the propagation mode near-field method employing an improved inverse analysis

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第9期79卷 21-29页

作者： Yabu, T Sawa, S Geshiro, M Faculty of Engineering Osaka Prefecture University Sakai Japan 593 Graduated from the Department of Electronic Engineering Doshisha University in 1989 and received his M.S. degree from Kyoto University in 1991. He withdrew from the doctoral program in 1993 and became a Research Associate at Osaka Prefecture University. He has been engaged in research on optical waveguides. Graduated from the Department of Electrical Engineering Osaka Prefecture in 1962 and joined Mitsubishi Electric remaining there until he left in 1964. He received his M.S. He received his M.S. and Dr. of Eng. degrees from Osaka University in 1967 and 1970 respectively. In 1970 he became an Associate Professor at Ehime University in the Department of Electronic Engineering where he was promoted to Professor in 1976. In 1991 he became Professor of Osaka Prefecture University in the Department of Electrical Engineering and in 1993 Professor in the Department of Electrical and Electronic Systems Engineering. He has been engaged in research on optical waveguides optical integrated circuits optical fibers and planar antennas. He is a member of IEEE Laser Society and the Institute of Electrical Engineers of Japan. Graduated in 1973 from the Department of Communication Engineering Osaka University and received his M.S. and Dr. of Eng. degrees in 1975 and 1978 respectively. In 1979 he became a Research Associate at Ehime University where he was promoted to an Associate Professor in 1984. In 1986–87 he was on leave at the University of Texas at Austin. In 1994 he became an Associate Professor at Osaka Prefecture University. He has been engaged in research on optics and millimeter wave and microwave waveguides. He is a member of IEEE.

A method to estimate the refractive index profile of an optical waveguide exists in which the optical intensity distribution of the only one propagation mode is used. Since this method requires only a microscope and a television camera, setup is extremely simple and inexpensive, thereby making the method practical. The differential processing method and the inverse analysis method have been proposed as methods to use the optical intensity distribution of only one propagation mode. The mechanisms of these methods that use the optical intensity distribution are presented in detail here. As a consequence, a new method that overcomes the difficulties in the previous methods, to be called Improved Inverse Analysis Method with Fewer Parameters, is proposed. Further, by using this proposed method, the index profiles of the step-index type optical fiber and the buried optical waveguide can be estimated in order for validity of the method to be studied.

关键词： optical waveguide refractive index profile image measurement

来源：评论

学校读者我要写书评

暂无评论

Degradation mechanism of contact resistance during window formation

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第1期79卷 93-100页

作者： Sekine, M Kakuhara, Y Kikkawa, T Nonmember NEC ULSI Device Development Laboratory Sagamihara Japan 229 Graduated in 1985 from Department of Metal Materials Osaka University where he received his Master's degree in 1988. He joined NEC in 1988. Graduated in 1984 from the Department of Electrical Engineering Aoyama Gakuin University and she received her Master's degree from Shinshu University in 1986. She joined NEC in 1986. She is a member of the Applied Physics Society. Graduated in 1974 from the Department of Electrical Engineering Shizuoka University where he received his Master's degree in 1976. He received his Ph.D. degree from Tokai University. He joined NEC in 1976. He is engaged in research and development of semiconductor LSI device and process. He was a Visiting Researcher at MIT from 1983 to 1984. He is currently a director of multilayer wire formation program ULSI Device Development Institute. He is a member of IEEE ICS and Applied Physics Society.

This paper describes a contact degradation mechanism during window formation followed by selective tungsten chemical vapor deposition (W-CVD). Contact resistances by using selective W-CVD were increased as the overetching rate increased. Surface analysis made it clear that the Si surface at the bottom of contact was damaged and oxygen atoms from dielectrics were introduced during window etching. These damage and oxygen atoms break Si-Si bonds and make Si-O bonds after additional ion implantation. The Si-O bonds degrade the valence-band density of states of the Si surface. Such a damaged surface will not react with WF6. This inactivation is the reason for contact degradation. Controlling the Si surface state by using the chemical dry etching (CDE) technique solves this problem.

关键词： selective W-CVD contact chemical dry etch

来源：评论

学校读者我要写书评

暂无评论

Improvement of convergence speed for subband adaptive digital filter using the multirate repeating method

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE 1995年第10期78卷 37-45页

作者： Kiya, H Nishikawa, K Ashihara, K Faculty of Technology Tokyo Metropolitan University Hachioji Japan 192-03 Members Kiyoshi Nshikawa graduated in 1990 from the Department of Electrical Engineering Tokyo Metropolitan University where he completed the Master's Program in 1992 and affiliated with Nippon Steel Co. Computer Systems Laboratory. He was a Research Associate in 1993 in the Department of Elect. Inf. Eng. Tokyo Metropolitan University engaged in research onadaptive signal processing and information source coding. He is a member of the IEEE. Associate Member

The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of the adaptive filter is related closely to the number of channels and the decimation ratio. The order of adaptive digital filter (ADF) is decreased greatly when the number of subbands is increased, and the decimation ratio is increased up to the maximum value. Then, however, the number of coefficient-updates per unit time is decreased, which results in the deterioration of the convergence Speed. From such a viewpoint, this paper discusses a method to improve the convergence speed, which is deteriorated in the subband adaptive system, due to the decimation. The idea of the proposed method is to utilize effectively the data which have been discarded in the decimation process and to improve the convergence speed. It is called the multirate repeating method. As the first step, the multirate repeating method is applied to the conventional subband adaptive system and the convergence speed is improved. Then a subband adaptive system is introduced in which the multirate repeating method can be utilized more effectively. As a result, a faster convergence is realized while retaining the ADF order-reduction effect, which is an advantage of the subband adaptive system.

关键词： adaptive signal processing subband adaptive system multirate repeating method rational decimation

来源：评论

学校读者我要写书评

暂无评论

Soliton system evaluations using fibers with dispersion and loss fluctuations

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第4期79卷 77-84页

作者： Ishiba, K Komatsu, T Takahara, M Faculty of Engineering Yamanashi University Kofu Japan 400 Graduated in 1994 from the Department of Electronic and Information Engineering where he is currently in the Master's program. He has been engaged in research on optical fiber soliton transmission. Received his B.S. and M.S. degrees in 1993 and 1995 respectively from the Department of Electronic and Information Engineering Yamanashi University. He joined NTT in April 1995. He has been engaged in research on simulation of the optical fiber soliton transmission and on the transmission system with flexibility in transmission speed. Graduated from the Department of Electrical Engineering Yamanashi University in 1965 and received his M.S. degree in 1967. He received his Ph.D. degree later. In 1967 he became a Research Associate of the Department of Electronic Engineering Yamanashi University. In 1991 he became a Professor of Electronic and Information Engineering. He has been engaged in research on special function theory nonlinear circuits optical communication systems and LAN systems. In 1984 he received a Book Award from I.E.I.C.E. In 1990–91 he was on leave at Southampton University. He is a member of IEEE.

In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity system. Several long-distance transmission experiments for high-density transmission by wavelength demultiplexing method (WDM) have been reported recently. However, more of the experimental examples have reported on soliton transmission than on WDM systems. Hence, the former is considered more advanced. It is necessary to prepare a fiber of a length of approximately 10,000 km for ultralong-distance transmission experiment. Since this is difficult to obtain, repetitive experiments are often the case. However, such an experiment does not disclose the effects of dispersion and loss fluctuation in the fiber. In this paper, the effect of fluctuation in dispersion and loss in the fiber is studied by simulation so that the resilience of the soliton to the variations of the fiber characteristics is evaluated.

关键词： optical soliton dispersion fluctuation loss fluctuation Gordon-Haus jitter

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：