• Title/Summary/Keyword: Electrical Units

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Synthesis and Electroconductivities of Poly(2-cyano-5-methoxyl-1,4-phenylenevinylene) and Copolymers

  • Hong-Ku Shim;Shin-Woong Kang;Do Hoon Hwang
    • Bulletin of the Korean Chemical Society
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    • v.14 no.1
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    • pp.43-47
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    • 1993
  • Poly(2-cyano-5-methoxy-1,4-phenylenevinylene), PCMPV and a series of PPV copolymers containing 2-cyano-5-methoxy-1,4-phenylenevinylene (CMPV) units were prepared via the water-soluble precursor method. They were obtained in films form and were easily doped with $FeCl_3$. Doping of undrawn and drawn films of PCMPV homopolymer with $FeCl_3$ led to conductivity of $10^{-5}-10^{-4}\;Scm^{-1}$. Conductivity of $FeCl_3$-doped copolymer films ranged from $10^{-3}$ 4.0 Scm$^{-1}$ depending on composition. As the content of CMPV units in the copolymer increased further, the electrical conductivity steadly decreased. Electronic effect by the CN substituent and morphological changes brought by copolymerization appear to interplay intricately resulting in the observation of a maximum conducting composition.

Electrical Properties of 4th generational Dendrimer Containing Azo-group (아조 기능기를 가진 제4세대 덴드리머의 전기적 특성)

  • Yang, Ki-Sung;Ock, Jin-Young;Jung, Sang-Bum;Kim, Chung-Kyun;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.904-907
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    • 2003
  • We synthesized dendrimers containing light switchable units, azobenzene group. To apply to the molecular level devices or data storage system using Langmuir-Blodgett(LB) film, we firstly investigated the monolayer behavior using the surface pressure-area(${\pi}-A$) isotherms at air-water interface. And then the surface pressure shift of monolayer by light irradiation was also measured to the dendrimer with azobezene group. As a result, the monolayer of dendrimer with azobenzene group showed the reversible photo-switching behavior by the isomerization of azobenzene group in their periphery. This results suggest that the dendrimers with azobenzene group can be applied to high efficient nano-device of molecular level. And we measured the electrical properties by MIM and STM. The dendrimer with azobenzene group compared trans form and cis form at electrical properties.

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Risk Structure Analysis for Cost of Capital : A Demonstrative Study using Financial Indices

  • Ling, Feng;Suzuki, Tomomichi;Ojima, Yoshikazu
    • International Journal of Quality Innovation
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    • v.7 no.3
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    • pp.1-14
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    • 2006
  • Economic value added (EVA) is introduced on two levels: as index for evaluation of corporation and as index for evaluation of business unit. In the latter case, application of one and the same cost of capital to all business units of a business corporation may be possible, but it is a fundamental policy for EVA to apply different cost of capital to business units with different risks. Estimate of cost of capital of business units is a problem to be resolved. The author, focusing on the question of the estimate of cost of capital of business units, has conducted a demonstrative study on risk structure of cost of capital estimates by using financial indices of Japanese manufacturers (37 automotive industries, 141 electrical and electronic machinery industries, 63 food processing industries, 98 chemical industries, 125 general machinery industries) for a period of 5 years from 1995 to 1999. The author presumes that $\beta$ is explained by a regression formula ${\beta}=B_0+{\Sigma}B_iY_i+{\alpha}$ ($Y_i$: financial indices) and selects 40 explanatory variables from financial statements as risk components. Using their financial indices, the author concludes through a series of statistical analyses that there is a good likelihood of estimating cost of capital for Japanese industries and is convinced that it will lead to more reliable and practical results by assigning averages and variances to 40 primary financial indices for a period of 3 to 5 years selected in this demonstrative study.

A Methodology for Reliability and Economic Analysis of Wind Energy Embedded Electric Power System (풍력을 포함하는 전력 시스템의 신뢰성과 경제성 해석 방법)

  • Jain, Amit;Min, Joon-Ki;Choi, Jae-Ho
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.1316-1318
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    • 2002
  • A methodology for reliability and economic analysis of wind embedded electric power system is presented in this paper. This is done by evaluating the reliability index, loss of load expectation (LOLE), for the power system with and without integration of wind system in the overall electric power system. Economic analysis of the wind energy embedded electric system is done in terms of conventional fuel saving assessment due to the use of wind power generation units.

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The design of the Sliding Mode Controller of Voltage Bus Conditioner for a DC Power Distribution System with multiple parallel loads in the Electrical Vehicles (다중 병렬 부하를 갖는 전기 자동차의 DC 배전 시스템을 위한 Voltage Bus Conditioner의 슬라이딩 모드 제어기 설계)

  • Chang, Han-Sol;Jeon, Yong-Sung;La, Jae-Du;Kim, Young-Jo;Kim, Young-Seok
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1141-1142
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    • 2011
  • An electrical vehicle (EV) is a huge issue in the automotive industry. The EV have many electrical units: electric motors, batteries, converters, ets. The DC power distribution system (PDS) is essential for the EV. The DC PDS offers many advantages. However, multiple loads in the DC PDS may affect the severe instability on the DC bus voltage. Therefore, a voltage bus conditioner (VBC) may use the DC PDS. The VBC is used to mitigate the voltage transient on the bus. In this paper, sliding mode controller (SMC) is designed for the VBC of DC PDS in the EV. The simulation results by PISM simulation package are presented for validating the proposed control technique.

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High-Performance Korean Morphological Analyzer Using the MapReduce Framework on the GPU

  • Cho, Shi-Won;Lee, Dong-Wook
    • Journal of Electrical Engineering and Technology
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    • v.6 no.4
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    • pp.573-579
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    • 2011
  • To meet the scalability and performance requirements of data analyses, which often involve voluminous data, efficient parallel or concurrent algorithms and frameworks are essential. We present a high-performance Korean morphological analyzer which employs the MapReduce framework on the graphics processing unit (GPU). MapReduce is a programming framework introduced by Google to aid the development of web search applications on a large number of central processing units (CPUs). GPUs are designed as a special-purpose co-processor. Their programming interfaces are typically formulated for graphics applications. Compared to CPUs, GPUs have greater computation power and memory bandwidth; however, GPUs are more difficult to program because of the design of their architectures. The performance of the Korean morphological analyzer using the MapReduce framework on the GPU is evaluated in comparison with the CPU-based model. The proposed Korean Morphological analyzer shows promising scalable performance on distributed computing with the GPU.

Dynamic Neural Units and Genetic Algorithms With Applications to the Control of Unknown Nonlinear Systems (동적 신경망과 Geneo-tic Algorithms를 적용한 비선형 시스템의 제어)

  • Cho, Hyun-Seob;Min, Jin-Kyoung;Roh, Yong-Gi;Jung, Byung-Jo;Jang, Sung-Whan
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.1943-1944
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    • 2006
  • "Dynamic Neural Unit"(DNU) based upon the topology of a reverberating circuit in a neuronal pool of the central nervous system. In this thesis, we present a genetic DNU-control scheme for unknown nonlinear systems. Our methodis different from those using supervised learning algorithms, such as the backpropagation (BP) algorithm, that needs training information in each step. The contributions of this thesis are the new approach to constructing neural network architecture and its trainin

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Hybrid Artificial Immune System Approach for Profit Based Unit Commitment Problem

  • Lakshmi, K.;Vasantharathna, S.
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.959-968
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    • 2013
  • This paper presents a new approach with artificial immune system algorithm to solve the profit based unit commitment problem. The objective of this work is to find the optimal generation scheduling and to maximize the profit of generation companies (Gencos) when subjected to various constraints such as power balance, spinning reserve, minimum up/down time and ramp rate limits. The proposed hybrid method is developed through adaptive search which is inspired from artificial immune system and genetic algorithm to carry out profit maximization of generation companies. The effectiveness of the proposed approach has been tested for different Gencos consists of 3, 10 and 36 generating units and the results are compared with the existing methods.

An Improved Dynamic Programming Approach to Economic Power Dispatch with Generator Constraints and Transmission Losses

  • Balamurugan, R.;Subramanian, S.
    • Journal of Electrical Engineering and Technology
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    • v.3 no.3
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    • pp.320-330
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    • 2008
  • This paper presents an improved dynamic programming (IDP) approach to solve the economic power dispatch problem including transmission losses in power systems. A detailed mathematical derivation of recursive dynamic programming approach for the economic power dispatch problem with transmission losses is presented. The transmission losses are augmented with the objective function using price factor. The generalized expression for optimal scheduling of thermal generating units derived in this article can be implemented for the solution of the economic power dispatch problem of a large-scale system. Six-unit, fifteen-unit, and forty-unit sample systems with non-linear characteristics of the generator, such as ramp-rate limits and prohibited operating zones are considered to illustrate the effectiveness of the proposed method. The proposed method results have been compared with the results of genetic algorithm and particle swarm optimization methods reported in the literature. Test results show that the proposed IDP approach can obtain a higher quality solution with better performance.

Optimal Generation Asset Arbitrage In Electricity Markets

  • Shahidehpour Mohammad;Li Tao;Choi Jaeseok
    • KIEE International Transactions on Power Engineering
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    • v.5A no.4
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    • pp.311-321
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    • 2005
  • A competitive generating company (GENCO) could maximize its payoff by optimizing its generation assets. This paper considers the GENCO's arbitrage problem using price-based unit commitment (PBUC). The GENCO could consider arbitrage opportunities in purchases from qualifying facilities (QFs) as well as simultaneous trades with spots markets for energy, ancillary services, emission, and fuel. Given forecasted hourly market prices for each market, the GENCO's generating asset arbitrage problem is formulated as a mixed integer program (MIP) and solved by a branch-and-cut algorithm. A GENCO with 54 thermal and 12 combined-cycle units is considered for analyzing the proposed formulation. The proposed case studies illustrate the significance of simultaneous arbitrage by applying PBUC to multi-commodity markets.