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International Symposium on Instrumentation Systems, Circuits and Transducers (INSCIT)

作者： Carlos Felipe G. Souza Henrique A. Cordeiro Davies W. de Lima Monteiro Telson Emmanuel O. Crespo Úrsula V. Abecassis Luciana P. Salles Graduated Program in Electrical Engineering — Federal University of Minas Gerais - UFMG Belo Horizonte MG Brasil Departament of Electronics and Telecommunications Federal Institute of Amazonas — IFAM Manaus AM Brazil

This paper presents a simplified instrument to measure the profile of a refractive object contactlessly based on the Hartmann-Shack (H-S) method. The sensing device has been designed with a simple CMOS Position-Sensitive Detector (PSD) of the quad-cell (QC) type, comprising four Active-Pixel Sensor (APS) pixels. A collimated laser beam traverses the object and the resulting wavefront is shaped by its profile. We demonstrate the reconstruction of this wavefront, and therefore the profile of the object, by sequentially sampling the wavefront through a moving single aperture coupled to a converging lens. Notwithstanding, we propose a sequence of steps for instrument calibration, among them the focalization step, using a feature of the QC not yet explored. A target lens was used as a test structure and its sagitta was measured, presenting an average error of 4% with respect to the datasheet value.

关键词： Lenses Laser beams Measurement by laser beam Transistors Quantum cascade lasers Apertures Optical sensors

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A Geographic Information System Application to Estimate the Weather-Dependent Power System Losses

A Geographic Information System Application to Estimate the ...

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IEEE International Autumn Meeting on Power, Electronics and Computing (ROPEC)

作者： Karen A. Villarreal Chaires Emilio Barocio Dunstano Del Puerto Flores Felix Rafael Segundo Sevilla Petr Korba Graduated program in electrical engineering Universidad de Guadalajara Guadalajara Jalisco México Electric Power Systems and Smart Grid Lab Zurich University of Applied Sciences ZHAW Winterthur Switzerland

ISBN: (纸本)9781665434287

The accuracy of weather-dependent power flow analysis for large interconnected systems can be significantly improved by including more electrical devices exposed to weather variables such as ambient temperature, wind speed and solar irradiance. The innovative part of the proposed approach is the combination of factors such as a voltage regulating transformer model, freely available weather data to feed the weather-dependent power flow algorithm, and a geographic visualization tool to display the results. To demonstrate the effectiveness of the proposed approach, the IEEE 118-bus system is used to analyze and compare the results of the weather-dependent power flow model versus a conventional power flow. In this case, it is used in the stationary analysis, the power flow temperature algorithms are performed in spatial visualization schemes. The results show that weather conditions directly affect the power system performance

关键词： Temperature sensors Temperature distribution Reactive power Wind speed Data visualization Transformers Data models

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

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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

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Sentiment Analysis of Hashtag Activism on Social Media Twitter

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

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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

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AUTOMATION OF PROPELLER INSPECTION AND FINISHING

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NAVAL ENGINEERS JOURNAL 1985年第4期97卷 124-131页

作者： STERN, H METZGER, R Howard K. Stern:is presently vice president of Robotic Vision Systems Inc. He received a bachelor of electrical engineering degree from College of the City of New York in 1960. Mr. Stern joined Dynell Electronics Corporation in 1971 and became part of the Robotic Vision Systems Inc. staff at the time of its spin-off from Dynell. He was program manager of the various three-dimensional sensing and replication systems constructed by Dynell and Robotic Vision Systems. As program manager his responsibilities encompassed technical administrative and operational areas. The first two portrait sculpture studio systems and the first three replication systems built by Robotic Vision Systems Inc. were designed manufactured and operated under his direction. Before joining Dynell Mr. Stern was a senior engineer at Instrument Systems Corporation and chief engineer of the Special Products Division of General Instrument Corporation. Prior to these positions Mr. Stern was chief engineer of Edo Commercial Corporation. At General Instrument and Edo Commercial he was responsible for the design and manufacture of military and commercial avionics equipment. Mr. Stern is presently responsible for directing the systems design and development for all of the company's programs. Robert J. Metzger:is currently engineering group leader at Robotic Vision Systems Inc. He graduated summa cum laude from the Cooper Union in 1972 with a bachelor of electrical engineering degree. Under sponsorship of a National Science Foundation graduate fellowship he graduated from the Massachusetts Institute of Technology in 1974 with the degrees of electrical engineer and master of science (electrical engineering). In 1979 Mr. Metzger graduated from Polytechnic Institute of New York with the degree of master of science (computer science). Since 1974 Mr. Metzger has been actively engaged in the design of systems and software for noncontact threedimensional optical measurement for both military and commercial applications. Of particular note are his c

Ship's propellers are currently measured by manual procedures using pitchometers, templates and gauges. This measurement process is extremely tedious, labor intensive and time consuming. In an effort to provide increased accuracy, repeatability and cost effectiveness in propeller manufacture, an automated propeller optical measurement system (APOMS) has been built which rapidly and automatically scans an entire ship's propeller using a 3-D vision sensor. This equipment is integrated with a propeller robotic automated templating system (PRATS) and the propeller optical finishing system (PROFS) which robotically template and grind the propeller to its final shape, using the APOMS-derived data for control feedback. The optical scanning and the final shape are both controlled by CAD/CAM data files describing the desired propeller shape. An automated propeller balancing system is incorporated into the PROFS equipment. The APOMS/PRATS/PROFS equipment is expected to provide lower propeller manufacturing costs.

关键词： PROPELLERS

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STUDY OF MATCHING LOAD ON NONUNIFORM COAXIAL TRANSMISSION LINE AND ITS APPLICATION TO WIDEBAND IMPEDANCE TRANSFORMER.

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Electronics and Communications in Japan, Part II: Electronics (English translation of Denshi Tsushin Gakkai Ronbunshi) 1987年第8期70卷 43-50页

作者： Sano, Seigo Mochizuki, Manabu Muto, Shinzo Ito, Chiaki Ito, Hiroshi Member Faculty of Engineering Yamanashi University Koufu Japan 400 Nonmember Shinzu Muto graduated from Yamanashi University Dept. of Electrical Engineering in 1970 and completed the Master's program in 1972. He became an Assistant at Yamanashi University Dept. of Electrical Engineering in 1973. He was on leave at Tohoku University in 1979. He has worked on organic dye lasers laser applications and waveguide devices. Member Applied Physics Society and Laser Society. Members

Two nonuniform coaxial transmission lines have been fabricated in which the primary parameters of the line vary parabolically and cosinusoidally. The characteristic impedances and the matched loads have been measured and the application to a broadband impedance transformer has been studied. The results show that the characteristic impedance distribution of the nonuniform coaxial transmission line does not coincide with the nominal characteristic impedance but agrees with the solution of the differential equation for the impedance derived from the telegrapher's equation. The condition providing for an effective matched load is determined and it is found that under this matched condition both of the nonuniform coaxial transmission line elements operate as an impedance transformer over an extremely wide frequency range exceeding 0. 5 GHz.

关键词： TELECOMMUNICATION LINES, HIGH FREQUENCY

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IMPROVEMENT OF ALGORITHM USING INTERVAL ANALYSIS FOR SOLUTION OF NONLINEAR CIRCUIT EQUATIONS.

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Electronics and Communications in Japan, Part I: Communications (English translation of Denshi Tsushin Gakkai Ronbunshi) 1987年第9期70卷 1-10页

作者： Okumura, Kohshi Kishima, Akira Saeki, Shuichi Faculty of Engineering Kyoto University Kyoto Japan 606 NTT Ltd. Chofu Japan 108 Shuichi Saeki graduated 1983 Dept. Electronic Eng. Fac. Eng. Kyoto University. Completed Master's program 1985 Graduate School and affiliated with NTT. Engaged in researches in interval analysis. Akira Kishima graduated 1951 Dept. Electrical Eng. Fac. Eng. Kyoto University. Completed Grad. School 1956. Assoc. Prof and presently Prof. Fac. Eng. (2nd Dept. Electrical Engineering) Kyoto University. Doctor of Engineering. Engaged in researches in electrical circuit power circuit and systems.

This paper describes an improvement of the solution by Krawczyk, Moore and Jones (KMJ algorithm) for nonlinear equations based on the interval analysis. When the KMJ algorithm is applied to practical problems such as the determination of the operating point of a multistable electronic circuit, a large computation time is required. It is shown that the algorithm can be improved in the computation time by a preprocessing and an elaboration in the region partitioning.

关键词： ELECTRIC NETWORKS, NONLINEAR

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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

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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.

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NUMERICAL METHOD FOR ANALYZING TRANSIENT AND STEADY STATES OF SINE WAVE OSCILLATOR CIRCUIT WITH STIFFNESS.

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Electronics and Communications in Japan, Part I: Communications (English translation of Denshi Tsushin Gakkai Ronbunshi) 1987年第10期70卷 1-11页

作者： Okumura, Kohshi Kishima, Akira Yasuda, Hisashi Faculty of Engineering Kyoto University Kyoto Japan 606 Kohshi Okumura graduated 1966 Dept. Electrical Eng. Fac. Eng. Kyoto University. Completed doctoral program 1971 Grad. School and Assistant Kyoto University. Doctor of Engineering. Presently Lecturer Dept. Electrical Eng. Engaged primarily in researches in nonlinear circuits lightning surge performance hysteresis characteristics and so forth. Member IEEJ IECEJ and IEEE. Hisashi Yasuda graduated 1981 Dept. Electrical Eng. Fac. Eng. Kyoto University. Completed Master's program 1983 Grad. School. Presently with Nippon Steel Co. Ltd. Member IECEJ. Nippon Steel Corporation Kitakyushu Japan 805 Akira Kishima graduated 1951 Dept. Electrical Eng. Fac. Eng. Kyoto University. Completed Grad. School 1956. Assoc. Prof. Presently Prof. Dept. Electrical Eng. Fac. Eng. Kyoto University. Doctor of Eng. Engaged in researches in electrical circuit power circuit and systems.

This paper proposes a method for analyzing the transient and steady states of a sine wave oscillator circuit with reactive elements which have large differences in their values. The circuit equation is represented by an autonomous nonlinear differential equation with the values of these elements. First, we describe the method for solving numerically the differential equation regardless of the stiffness by the asymptotic method developed by Krylov, Bogolyubov and Mitropolskiy. Second, we present the method for obtaining solutions of the differential equation with regard to the stiffness by combining the asymptotic method with numerical integration.

关键词： OSCILLATORS

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The Navy Standard Hardware program

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Naval Engineers Journal 1974年第5期86卷 79-91页

作者： MERZ, JOHN A. The author graduated from the University of Notre Dame in 1955 at which time he received his BS degree in Electrical Engineering. He is presently the Program Manager for Microcircuit Developments and Advanced Modular Concepts at the Naval Electronic Systems Command where previously he had been the Program Manager for the Standard Hardware Program responsible for the overall financial administrative and technical management of the program. He is a member of the Institute of Electrical and Electronic Engineers and a registered Professional Engineer in the District of Columbia.

The Standard Hardware program represents the start of an endeavor to standardize the modular building blocks of all Navy solid state electronic systems. When fully expanded, this vital program will lower the cost and increase the availability of electronic systems for the operating forces. The administrative, electrical and mechanical principles of the program are explained. It is shown that forecasting and controlling system costs can be simplified because: 1) the characteristics of the standard modules are known quantities;2) the designs have been tested;3) Vendors have been qualified, and 4) production costs are known and stable. The impact on maintenance and training is discussed as a function of using modules that are inexpensive enough so that they can be economically discarded upon failure. Statistics derived from Fleet operations are shown to illustrate much better than average reliability for the standard modules. © 1974 American Society of Naval Engineers

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