著者
大山 和伸
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.123, no.2, pp.63-66, 2003-02-01
被引用文献数
14 7

The history of motor technology began with the discovery of electromagnetic induction by Faraday. Various kinds of motors were developed by the recent progress of the fundamental technology (magnetic structure, magnetic material, drive circuit, control method). Especially, motors using the reluctance torque have many advantages and some of them are used as high efficient motors. This paper overviews recent advances of reluctance torque assisted motors such as Switched Reluctance Motor (SRM), Synchronous Reluctance Motor (SynRM) and Interior Permanent Magnet Synchronous Motor (IPMSM).
著者
朴 炳植
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)
巻号頁・発行日
vol.123, no.7, pp.808-813, 2003-07-01
被引用文献数
7 1

A CO<SUB>2</SUB>-capturing NO<SUB>x</SUB>-free H<SUB>2</SUB>O turbine power generation system is proposed in which middle pressure steam produced in a thermal power plant is utilized to increase generated power when demand for electricity is large. The proposed system can capture all the generated CO<SUB>2</SUB> based on the oxygen combustion method and emits no NO<SUB>x</SUB>, so that it causes no urban and global environmental problems. A combined cycle power generation system with 200MW gas turbine power output is adopted as an example of a thermal power plant. It was assumed that 32 t/h of steam with 25kg/cm<SUP>2</SUP> pressure produced at waste heat recovery boiler was utilized in the proposed system.It has been shown through simulation study that increase of power output by 11.8MW or 4.51% of the rated output is possible with no efficiency decrease. The amount of CO<SUB>2</SUB> reduction is estimated to be 19600t/y.The unit cost of generated power is estimated to be 8.38yen/kWh, annual gross profit of the proposed system 271 million yen, depreciation year 4.87, and thus the proposed system is estimated to be economically feasible.
著者
吉野 純 北 裕幸 田中 英一 長谷川 淳 久保 宏 世永 茂
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)
巻号頁・発行日
vol.124, no.5, pp.723-732, 2004-05-01
被引用文献数
7 2

Recently, a number of electric consumers have concerned about the reliability of electricity to be served. For example, some consumers need the electricity with a higher reliability by the automation of manufacturing processes. On the other hand, some consumers need the electricity of a cheaper price even if the reliability becomes a little worse. Under such circumstances, it is necessary that power suppliers evaluate the needs of every consumers precisely and propose the most desirable measures for meeting their requirements. This paper develops a tool to analyze the reliability for high-voltage supplied consumers quantitatively. Further, this paper presents a method for evaluating the outage cost of consumers to help them choose the most appropriate measures for maintaining the reliability. The proposed method applies the fuzzy reasoning approach. The validity of the proposed method is ascertained through some numerical simulations.
著者
雨宮 正樹 今江 理人 藤井 靖久 鈴山 智也 内藤 孝 浦川 順治 海老原 清一 照沼 信浩
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.130, no.4, pp.644-650, 2010-04-01

A precise frequency dissemination system using optical fiber is studied. The purpose of the system is to transmit frequency standard with little deterioration to distant many users. It is composed of a phase compensation transmitter, bidirectional optical amplifiers, optical amplified distributor, and receiver. The system target is to achieve a stable transmission of hydrogen maser class signals. For short term stability, it is shown the required optical received power to realize the Allan deviation of 1×10<sup>-13</sup> (averaging time of 1 s). For long term stability, a new compensation method using third wavelength transmission is effective to suppress phase fluctuation induced by fiber temperature change. Experimental result shows stability of 8×10<sup>-17</sup> at 10<sup>5</sup> s in a fiber link of 160 km in total with one bidirectional optical amplifier.
著者
税所 真前 伊瀬 敏史 辻 毅一郎
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)
巻号頁・発行日
vol.123, no.8, pp.964-973, 2003-08-01
被引用文献数
19 14

In the large-scale factories like ironworks, many power electronic inverter loads exist, and these inverter loads are connected into ac systems by using rectifiers. On the other hand, DGs (Distributed Generators) such as photovoltaic generators and fuel cells, or ESSs (Energy Storage Systems) such as secondary batteries and SMESs (Superconducting Magnetic Energy Strages), which are dc power sources will be introduced to distribution systems more and more. These are connected into ac systems by using inverters. Therefore, it is expected that some countermeasures to achieve a dc distribution system which can reduce power losses due to rectifiers and inverters, should be developed.<BR>In this paper, a dc loop type distribution system is proposed as one of the new dc distribution system configurations. The calculation results of power losses for the dc loop type distribution system are compared with those for an ac distribution system. Moreover, this paper shows configurations and simulation results of the inverter, bi-directional rectifier and PFC (Power Factor Corrector) used in this system.
著者
真木 紘一 田中 照也
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. A, 基礎・材料・共通部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A, A publication of Fundamentals and Materials Society (ISSN:03854205)
巻号頁・発行日
vol.129, no.9, pp.595-604, 2009-09-01

Subjects in radiation shielding for the low aspect ratio tokamak commercial reactor VECTOR are discussed and their solutions are presented. The subjects and design criteria of radiation shielding in ITER are consulted to discussion in the present work, because of these in commercial reactors same as those in the ITER.
著者
堂脇 清志 森 俊介 福島 千尋 浅井 貴康
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.123, no.10, pp.1670-1679, 2003-10-01
被引用文献数
2 1

This paper describes on a comprehensive economic analysis concerning biomass gasification systems. In Japan, promoting biomass energy systems in domestic area comes to be expected recently. However, there are some problems in achieving this project. The costs for plant building are very expensive comparing with conventional ones. Accordingly, the unit costs of electricity increase up to as high as other environmental energy systems.<br>In this paper, biomass energy systems using woody biomass are proposed from the viewpoints of successful environmental business. The biomass integrated gasification combined cycle (BIGCC) plant by Independent Power Producer and biomass gasification co-generation (BGCGS) plant in the sawmill or the asphalt-concrete production factory will have opportunities to be implemented in the near future. Our analysis concludes that the systems proposed in this paper provide the following outcomes with subsidies: (1) the generating cost in BIGCC becomes from 15.1 to 36.6 yen/kWh, (2) the generating cost in BGCGS becomes from 2.6 to 32.2 yen/kWh, (3) the cost reduction of products in BGCGS in asphalt factory comes to about 60 million yen per year.
著者
七夕 高也 清水 久代 篠村 知子 高野 誠 宮村 中村 浩子 斎藤 隆文
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.128, no.6, pp.962-969, 2008-06-01
被引用文献数
3 1

We developed an imaging system and image analysis software for phenotype analysis of rice seedlings growth. The developed imaging system could collect rice seedlings growth images in test tubes every 10 minutes. The image analysis software could detect leaf tip points and collect measurement of leaf height. Using this system, we could obtain detailed measurement and analysis phenotype of rice seedlings growth depends on time parameters, germination timing and leaf elongation timing.
著者
西 貴行 藤吉 弘亘 梅崎 太造
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.124, no.12, pp.2433-2438, 2004-12-01

In archiving video for surveillance, frame-based coding has been used and it makes storage size large because the whole image is stored even if there is no object in the image. On the other hand, object-based coding has the capability to make storage size small, because it distinguishes between the foreground and the background regions of the image, and stores only foreground objects such as people. This paper describes object-based coding by pixel state analysis. In our method, pixel state analysis detects the foreground objects and background regions in video frames. Furthermore, it distinguishes foreground object pixels as <i>stationary</i> or <i>transient</i> pixels. For <i>stationary</i> pixels, it is possible to restore the color intensity by refering to the same pixel location in the last frame. Therefore, our method makes the storage size smaller. Additionally, the <i>transient</i> pixels of foreground objects are compressed using LZH codec. Since LZH codec uses lossless compression, the object region can be compressed with lesser loss in image quality. We have evaluated our method over 9 test sequences and obtained an improvement of 15% in compression ratio and better quality for the moving parts of the object region compared to MPEG-4.
著者
西川 寛
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)
巻号頁・発行日
vol.127, no.7, pp.827-832, 2007-07-01
被引用文献数
2 2

Following the examples of other countries, in April 2005 Japan launched wholesale electric power exchange operations as a primary item of system reform in line with electric liberalization. Only two years have passed since the initiation of these operations. However, in the summer of 2005, the surge in market prices was evident, which suggested that certain measures should be taken to confront potential market risks. Establishing a useful system for forecasting market prices through the modeling of price fluctuations in the wholesale electric market became essential. Currently, various price models are being proposed. Taking both the limited amount of data and the model's purpose into consideration, this study adopted the univariate time series model.<br>We conducted a time series analysis on the open price indexes in the JEPX spot market with the Box-Jenkins method. Since a seven-day cycle can be observed in the data, we adopted the seasonal ARIMA model. In accordance with the procedures of the Box-Jenkins method, we determined the degree of the model's polynomial using the autocorrelation and partial autocorrelation of the data and estimated the parameters of the model with the maximum likelihood method. We conducted a forecast on next day JEPX spot market prices with this time series model and examined its validity and utility as a forecasting tool.<br>Price forecasts made with this model require only a small amount of data and will save substantial analysis work. Consequently, this method is expected to be widely used by market participants as the reference data for their bid pricing.
著者
村田 博士 小野田 崇 由本 勝久 中野 幸夫 近藤 修平
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.124, no.9, pp.1874-1880, 2004-09-01
被引用文献数
13 7

This paper presents applying results of four estimation algorithms of non-intrusive monitoring system for real household. We conclude that all algorithms have practicable ability. 1) support vector machine(SVM): SVM was used to estimate ON/OFF states for fluorescent and refrigerator. SVM has the performance equivalent to best performance of sigmoid function networks(SFN). However, SVM has high estimating ability constantly. 2) RBF networks(RBFN): RBFN was used to estimate power consumption for air conditioner. RBFN has the performance equivalent to best performance of SFN. However, RBFN has high estimating ability constantly. 3) step change detection method(SCD): SCD was used to estimate ON/OFF states and power consumption for IH cooking range. SCD does not need the necessary learning process for SFN and has higher estimating ability than SFN. 4) spectrum reference method(SRM): SRM was used to estimate working conditions for rice cocker and washing machine. SRM is able to estimate these working conditions that cannot be estimated by earlier methods.
著者
副島 勝則 樋口 剛 阿部 貴志 平山 斉 河野 勝一
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.130, no.2, pp.181-188, 2010-02-01
被引用文献数
2

We have developed a low-speed and low-capacity wind power generator. In this paper, we introduce the outline of the 5kW multi-polar synchronous generator that generates the electric power efficiently from 50rpm to 180rpm. The generator is produced by a magnetic powder core for cost reduction. We also express the outline and field test results of the low-capacity power plant constructed in Ohmura City, Nagasaki.
著者
福地 哲生 名雪 琢弥 根本 孝七 内野 喜一郎
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.123, no.9, pp.1531-1536, 2003-09-01
被引用文献数
7 4

An acousto-optic laser deflector was used as a shutter for high-speed imaging of laser interference fringes using an ordinary CCD camera. The exposure duration was set by the pulse width of the high frequency signal applied to the acousto-optic deflector. Changes in laser interference fringes due to an impulse discharge in air were obtained at an exposure duration of 4μs. By applying a sequence of high frequency signals with different frequency, the beam was deflected to four different angles at different times, allowing four interference images to be captured on a single video frame. This was used for time-resolved imaging of the interference fringe pattern.
著者
小林 慎一 白井 康之 比屋根 一雄 粂野 文洋 犬島 浩 山内 規義
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.125, no.5, pp.720-729, 2005-05-01
被引用文献数
1

Information technology is increasingly important in recent years for the development of our society. IT has brought many changes to everything in our society with incredible speed. Hence, when we investigate R & D themes or plan business strategies in IT, we must understand overall situation around the target technology area besides technology itself. Especially it is crucial to understand overall situation as time series to know what will happen in the near future in the target area. For this purpose, we developed a method to generate Multiple-phased trend maps automatically based on the Internet content. Furthermore, we introduced quantitative indicators to analyze near future possible changes. According to the evaluation of this method we got successful and interesting results.
著者
瀬崎 直人 黄瀬 浩一
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.129, no.3, pp.475-480, 2009-03-01

In this paper, we propose a system for recommending tags of images. The proposed method presents to its user various tags with high precision by taking into account both the co-occurrence of tags and tags of similar images. Additional search with the user feedback enables us to find some new tags relevant to the image of interest. In order to test the proposed method, we compare it with a method based only on the co-occurrence of tags, as well as a method based only on the similarity of images. From the experimental results using 16002 images, we have confirmed that the proposed method is capable of finding more tags as compared to the methods for comparison. We have also confirmed that the additional search is effective to find additional tags.
著者
嶋田 香 間普 真吾 森川 英治 平澤 宏太郎 古月 敬之
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.128, no.5, pp.795-803, 2008-05-01
被引用文献数
2 1

A method of class association rule mining from incomplete databases is proposed using Genetic Network Programming (GNP). GNP is one of the evolutionary optimization techniques, which uses the directed graph structure. An incomplete database includes missing data in some tuples, however, the proposed method can extract important rules using these tuples, and users can define the conditions of important rules flexibly. Generally, it is not easy for Aprior-like methods to extract important rules from incomplete database, so we have estimated the performances of the rule extraction and classification of the proposed method using incomplete data set. The results showed that the accuracy of classification of the proposed method is favorable even if some tuples include missing data.
著者
金久保 正明 萩原 将文
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C, 電子・情報・システム部門誌 = The transactions of the Institute of Electrical Engineers of Japan. C, A publication of Electronics, Information and System Society (ISSN:03854221)
巻号頁・発行日
vol.128, no.6, pp.997-1004, 2008-06-01

Frequent patterns mining is one of the important problems in data mining. Generally, the number of potential rules grows rapidly as the size of database increases. It is therefore hard for a user to extract the association rules. To avoid such a difficulty, we propose a new method for association rule induction with pseudo artificial life approach. The proposed method is to decide whether there exists an item set which contains N or more items in two transactions. If it exists, a series of item sets which are contained in the part of transactions will be recorded. The iteration of this step contributes to the extraction of association rules. It is not necessary to calculate the huge number of candidate rules. In the evaluation test, we compared the extracted association rules using our method with the rules using other algorithms like Apriori algorithm. As a result of the evaluation using huge retail market basket data, our method is approximately 10 and 20 times faster than the Apriori algorithm and many its variants.
著者
本郷 保二 道下 幸志
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. B, 電力・エネルギー部門誌 = The transactions of the Institute of Electrical Engineers of Japan. B, A publication of Power and Energy Society (ISSN:03854213)
巻号頁・発行日
vol.128, no.12, pp.1535-1542, 2008-12-01
被引用文献数
6 1

The overvoltage associated with direct lightning hits has been the important factor for the insulation design of a distribution line. In this paper, the sparkover rate of a medium-voltage line associated with direct lightning hits is investigated based on numerical calculations obtained by using EMTP and statistical analysis by taking account of the correlation between the peak value and the front duration of return-stroke current waveform. When the line is equipped with surge arresters at the interval of 100m in addition to the overhead ground wire, the sparkover rate associated with subsequent strokes is higher than that associated with first strokes. This demonstrates the importance of the study of current parameters for subsequent strokes.
著者
市川 麻理子 柴田 昌明
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.127, no.6, pp.651-652, 2007

This paper proposes a visual servo control method for exploring motion of eye-in-hand robot to recognize a three-dimensional object. Optimal motion is based on the strategy in which the position estimation precision of the feature points gets improved when the feature points move widely, and the optimal robot motion provides the widest transitions of the feature points per unit robot motion, so that the robot should be controlled to purse such motion. In addition, this paper describes the way to reduce a large number of calculation efforts. The validity of our approach is confirmed in the several experimental results.
著者
上保 徹志
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌. C (ISSN:03854221)
巻号頁・発行日
vol.125, no.11, pp.1646-1651, 2005
被引用文献数
28 13

Various types of radars have been developed and used until now—such as Pulse, FM-CW, and Spread Spectrum. Additionally, another type of radar has been proposed recently. The radar measures distance by using standing wave and has been named as "Standing Wave Radar." Standing wave radar has a shorter minimum detectable range and higher accuracy compared to other types. However, the radar can not measure distance down to zero meters like other types of radars. Minimum detectable range of the standing wave radar depends on a usable frequency range. A wider frequency range is required if we need to measure shorter distance. We show a new method for measuring distance down to zero meters without expanding the frequency range. Specifically, we derive an analytic signal, which is a complex sinusoidal signal, by processing the signals obtained from multiple detectors, and we calculate and obtain distances by Fourier transform of the analytic signal. We then verify the validity of our method by simulations based on numerical calculation. The results show that it is possible to measure distance down to zero meters. In our method, measurement errors are caused by gain deviation of the detectors. They are several cm if the gain deviations are less than ±1%. Prevalent radars still have a common defect that they can not measure distance from zero to the minimum detectable range. We expect that the defect will be eliminated by putting our method into practical use.