• 제목/요약/키워드: Electrical Units

검색결과 712건 처리시간 0.023초

A Korean Flight Reservation System Using Continuous Speech Recognition

  • Choi, Jong-Ryong;Kim, Bum-Koog;Chung, Hyun-Yeol;Nakagawa, Seiichi
    • The Journal of the Acoustical Society of Korea
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    • 제15권3E호
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    • pp.60-65
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    • 1996
  • This paper describes on the Korean continuous speech recognition system for flight reservation. It adopts a frame-synchronous One-Pass DP search algorithm driven by syntactic constraints of context free grammar(CFG). For recognition, 48 phoneme-like units(PLU) were defined and used as basic units for acoustic modeling of Korean. This modeling was conducted using a HMM technique, where each model has 4-states 3-continuous output probability distributions and 3-discrete-duration distributions. Language modeling by CFG was also applied to the task domain of flight reservation, which consisted of 346 words and 422 rewriting rules. In the tests, the sentence recognition rate of 62.6% was obtained after speaker adaptation.

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발전력의 경쟁적 입찰전략과 전략적 보수계획에 대한 결합모형 연구 (Analysis on a Combined Model of Competitive Bidding and Strategic Maintenance Scheduling of Generating Units)

  • 이광호
    • 대한전기학회논문지:전력기술부문A
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    • 제55권9호
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    • pp.392-398
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    • 2006
  • Maintenance scheduling of generating units (MSU) has strategic dimension in an oligopolistic market. Strategic MSU of gencos can affect a market power through capacity withdrawal which is related to bidding strategy in an generation wholesale market. This paper presents a combined framework that models the interrelation between competitive bidding and strategic MSU. The combined game model is represented as some sub-optimization problems of a market operator (MO) and gencos, that should be solved through bi-level optimization scheme. The gradient method with dual variables is also adopted to calculate a Nash Equilibrium (NE) by an iterative update technique in this paper. Illustrative numerical example shows that NE of a supply function equilibrium is obtained properly by using proposed solution technique. The MSU made by MO is compared with that by each genco and that under perfect competition market.

Study of Cache Performance on GPGPU

  • Choi, Kyu Hyun;Kim, Seon Wook
    • IEIE Transactions on Smart Processing and Computing
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    • 제4권2호
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    • pp.78-82
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    • 2015
  • General-purpose graphics processing units (GPGPUs) provide tremendous computational and processing power. Despite the latency hiding mechanism, a GPU architecture requires high memory bandwidth and lower latency between computational units and the memory system. For this reason, the current GPU architecture has private L1 caches in each core and a shared L2 cache to increase performance by reducing memory latency. But in some cases, this CPU-like cache design is not suitable for GPGPUs. In this paper, we analyze detailed cache performance related to GPGPU application characteristics, and suggest technical alternatives for the GPGPU architecture as future work.

이동통신 단말기용 SLA(Scanned Linear Array) 적용에 관한 연구 (A study on SLA(Scanned Linear Array) Applications for Mobile Communication Units)

  • 김인회;안원석;문현찬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.275-278
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    • 1998
  • In recent years, miniaturization has become the key factor in the development of mobile communication system. Portable communications and computing devices suffer from two conflicting requirements which are device size to be as small as possible and large, high resolution display. These problems can be solved by virtual display. Any display in which the user views an image through an optical system is a virtual display. It provides a display which is high resolution, appears large to the viewer and at the same time occupies little physical space. In this study, handhold units of mobile communication was investigated through use of the SLA(Scanned Linear Array). The basic SLA mechanism comprises a linear array of LED's, a magnifying lens, and a scan mirror. To optimize virtual image, we investigated optical system design and operating condition for each part.

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Tabu 탐색법을 이용한 화력 발전기의 기동정지계획 (Thermal Unit Commitment using Tabu Search)

  • 천희주;김형수;황기현;문경준;박준호
    • 대한전기학회논문지:전력기술부문A
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    • 제49권2호
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    • pp.70-77
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    • 2000
  • This paper proposes a method of solving a unit commitment problem using tabu search (TS) which is heuristic algorithm. Ts is a local search method that starts from any initial solution and attempts to determine a better solution using memory structures. In this paper, to reduce the computation time for finding the optimal solution, changing tabu list size as intensification strategy and path relinking method as diversification strategy are proposed. To show the usefulness of the proposed method, we simulated for 10 units system and 110 units system. Numerical results show improvements in the generation costs and the computation time compared with priority list, genetic algorithm(GA), and hybrid GA.

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동시자기진단이 적용한 마이크로푸로세서의 하드웨어 구성에 관한연구 (A Design Approach to Concurrent Self-Diagnosable Microprocessor)

  • 하경재;신명철
    • 대한전기학회논문지
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    • 제38권1호
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    • pp.68-77
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    • 1989
  • In this paper, a design approch is presented for a concurrent self-diagnosable microprocessor. An efficient diagnostic procedure to dynamically test the processor functional units decomposed by each insturction, concurrently with a program under execution is suggested. The basic goals of the proposed design approach are the low hardware overhead, no increase in the pin count and the minimal change of the initial design concepts on conventional microprocessors. The results of the performance of the suggested self-diagnosing hardware for an 8080 type microprocessor show that the suggested diagnosis scheme would be efficiently applicable, since diagnosing the processor functional units can be completed in a reasonably short time with the execution of an arbitrarily chosen sample program.

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경사 투영법을 이용한 발전사업자의 경제급전 (Economic Dispatch of Thermal Units of a GENCO Using the Gradient Projection Method)

  • 정정원
    • 대한전기학회논문지:전력기술부문A
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    • 제52권9호
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    • pp.550-556
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    • 2003
  • Price-based unit commitment is one of bidding strategies which a Genco may take in a practical manner. For that purpose, it is required for a Genco to decide output levels of its generators at each trade period. In this paper, an economic dispatch of thermal units is proposed considering the quantity of reserve contracts. A gradient projection algorithm is adopted as an optimization tool. A direct form of a projection matrix without any calculation of matrix inverse and multiplications is induced. Besides, it is proved that there is no need to check one of the two optimality conditions in the gradient projection method, which also requires matrix inverse and multiplications.

Probabilistic Load Flow for Power Systems with Wind Power Considering the Multi-time Scale Dispatching Strategy

  • Qin, Chao;Yu, Yixin;Zeng, Yuan
    • Journal of Electrical Engineering and Technology
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    • 제13권4호
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    • pp.1494-1503
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    • 2018
  • This paper proposes a novel probabilistic load flow model for power systems integrated with large-scale wind power, which considers the multi-time scale dispatching features. The ramp limitations of the units and the steady-state security constraints of the network have been comprehensively considered for the entire duration of the study period; thus, the coupling of the system operation states at different time sections has been taken into account. For each time section, the automatic generation control (AGC) strategy is considered, and all variations associated with the wind power and loads are compensated by all AGC units. Cumulants and the Gram-Charlier expansion are used to solve the proposed model. The effectiveness of the proposed method is validated using the modified IEEE RTS 24-bus system and the modified IEEE 118-bus system.

Synthesis and Electrical Conductivities of Poly(1,4-phenylenevinylene-co-2,3,5,6-tetramethyl-1,4-phenylenevinylene)s

  • Jin, Jung-Il;Kang, Heung-Joong;Shim, Hong-Ku
    • Bulletin of the Korean Chemical Society
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    • 제11권5호
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    • pp.415-420
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    • 1990
  • A series of copolymers of poly(1,4-phenylenevinylene-co-2,3,5,6-tetramethyl- 1,4-phenylenevinylene), poly(PV-co-TMPV), were prepared in film forms from the precursor polymer films. The sulfonium salt precursor polymers were synthesized by copolymerization of the mixtures of the respective bis(sulfonium salt) monomers. All of the copolymer films could be doped with $FeCl_3$ to have high electrical conductivities and they showed good air stability. The maximum conductivity of the $FeCl_3$-doped films ranged $10^{-3}\;to\;10^2Scm^{-1}$ depending on the composition of the copolymer films. However, these copolymer films could not be doped with iodine. The coplanarity of PV and TMPV units in the main chain appears to be affected by steric effect of the methyl groups in the TMPV units.

A New Recurrent Neural Network Architecture for Pattern Recognition and Its Convergence Results

  • Lee, Seong-Whan;Kim, Young-Joon;Song, Hee-Heon
    • Journal of Electrical Engineering and information Science
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    • 제1권1호
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    • pp.108-117
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    • 1996
  • In this paper, we propose a new type of recurrent neural network architecture in which each output unit is connected with itself and fully-connected with other output units and all hidden units. The proposed recurrent network differs from Jordan's and Elman's recurrent networks in view of functions and architectures because it was originally extended from the multilayer feedforward neural network for improving the discrimination and generalization power. We also prove the convergence property of learning algorithm of the proposed recurrent neural network and analyze the performance of the proposed recurrent neural network by performing recognition experiments with the totally unconstrained handwritten numeral database of Concordia University of Canada. Experimental results confirmed that the proposed recurrent neural network improves the discrimination and generalization power in recognizing spatial patterns.

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