• 제목/요약/키워드: ahead

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4-Bit 카운터 74LS163의 연결방법에 대한 분석 (Analysis of the Method of Cascading 74LS163 4-Bit Binary Counters)

  • 유준복;정태상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 D
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    • pp.794-796
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    • 2000
  • This paper analyzes the method of cascading 74LS163 4-Bit Binary Counters. The 74LS163 4-Bit Binary Counter has synchronous LD. CLR functions and especially ENT, ENP, RCO to cascade some chips in order to count more 4bit binary number. The maximum operating frequency may vary according to the method of cascading. The Data sheet from Texas Instruments introduces two methods, The Ripple Carry Mode Circuit and The Carry Look Ahead Circuit, and shows that The Carry Look Ahead Circuit is more efficient than the other. However, there are only little information for user to understand and apply this to other circuits. Thus, we not only analyzed the two methods but also compared with each other in the point of performance.

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자기회귀누적이동평균 모형을 이용한 전일 계통한계가격 예측 (A Day-Ahead System Marginal Price Forecasting Using ARIMA Model)

  • 김대용;이찬주;이명환;박종배;신중린
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.819-821
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    • 2005
  • Since the System Marginal Price (SMP) is a vital factor to the market entities who intend to maximize the their profit, the short-term marginal price forecasting should be performed correctly. In a electricity market, the short-term trading between the market entities can be generally affected a short-term market price. Therefore, the exact forecasting of SMP can influence on the profit of market participants. This paper presents a methodology of day-ahead SMP foretasting using Autoregressive Integrated Moving Average (ARIMA). To show the efficiency and effectiveness of the proposed method, the numerical studies have been performed using historical data of SMP in 2004.

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Grey 모형을 이용한 홍수량 예측 (Real Time Flood Forecasting Using a Grey Model)

  • 강민구;박승우
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.535-538
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    • 2003
  • A Grey model was developed to forecast short-term runoff from the Naju watershed in Korea. In calibration, the root mean square error(RMSE) of the simulated runoff of six hours ahead using Grey model ranged from 6.3 to $290.52m^3/s,\;R^2$ ranged from 0.91 to 0.99, compared to the observed data. In verification, the RMSE ranged from 75.7 to $218.9m^3/s,\;R^2$ ranged from 0.87 to 0.96, compared to the observed data. The results in this study demonstrate that the proposed model can reasonably forecast runoff one to six hours ahead.

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사이버교육에 따른 학교건축계획의 방향에 관한연구 (A Study on the Architectural Planning of School According to the Cyber Education)

  • 맹준호
    • 교육녹색환경연구
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    • 제3권2호
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    • pp.71-86
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    • 2003
  • Informationization is fast progressing in Korean and the informationization of education is also moving ahead fast. With informationization of education going fast ahead, cyber education is also increasing. Given such scenario, we should establish countermeasures not only to accommodate the current curriculum but also to accommodate the surplus school facilities created by cyber education by compartmentalizing the classrooms for future life-long education, lease and sale in lots. In conclusion, the school construction plan should be established to systematically cope with the future changes systematically.

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Simulation study on one-step ahead control of a photovoltaic energy storage system

  • Sugisaka, Masanori;Kuroiwa, Kenzo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집(한일합동학술편); 한국과학기술대학, 충남; 16-17 Oct. 1987
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    • pp.741-746
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    • 1987
  • Solar cell which transforms the light energy into the electric energy from Sun comes into prominence as a new energy for next generation. However, it is difficult to obtain the stable output voltage and current from the solar cell due to the uncertainty in weather conditions, etc, In the present paper, two types of control laws are considered for regulating the input voltage in a photovoltaic energy storage system such as the system with the super conducting magnetic energy storage. (1) Oone is the design of optimal controller. (2) The other is that of weighted minimum prediction error controllers (weighted one-step ahead controllers). Simulation study for the above controllers is performed to see how they work and to get preliminary knowledge in the regulation of the input voltage to the experimental photovoltaic energy storage system.

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Ad-hoc 네트워크에서 Look-ahead Selective Flooding을 이용한 On-Demand 라우팅 프로토콜 성능 개선 (Performance Evaluation of On-Demand Routing Protocol using Look-ahead Selective Flooding in Ad-hoc Network)

  • Yo-chan Ahn
    • Journal of Information Technology Applications and Management
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    • 제10권2호
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    • pp.61-71
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    • 2003
  • Ad-hoc networks are characterized by multi-hop wireless links, frequently changing network topology and the need for efficient dynamic routing protocols. In an Ad-hoc network, each host assumes the role of a router and relays packets toward final destinations Because a packet is broadcast to all neighboring nodes, the optimality criteria of wireless network routing is different from that of wired network routing. tn this paper 1 point out the more important cost factor than the number of links in the Ad-hoc network. A class routing protocols called on-demand protocols has recently found attention because of their low routing overhead since it performs a blind flooding to look for a path. In this paper, 1 propose the method which reduces overhead by using the information of neighboring nodes and doing a selective flooding. Simulation results demonstrate better reduction of routing overheads with this scheme.

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적응 일반형 예측제어 설계에 관한 연구 (A study on the design of adaptive generalized predictive control)

  • 김창회;이상정
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.176-181
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    • 1992
  • In this paper, an adaptive generalized predictive control(GPC) algorithm which minimizes a N-stage cost function is proposed. The resulting controller is based on GPC algorithm and can be used in unknown plant parameters as the parameters of one step ahead predictor are estimated by recursive least squares method. The estimated parameters are extended to G,P, and F amtrix which contain the parameters of N step ahead predictors. And the minimization of cost function assuming no constraints on future controls results in the projected control increment vector. Hence this adaptive GPC algorithm can be used for either unknown system or varing system parameters, and it is also shown through simulations that the algorithm is robust to the variation of system parameters. This adaptive GPC scheme is shown to have the same stability properties as the deterministic GPC, and requires small amount of calculation compared to other adaptive algorithms which minimize N-stage cost function. Especially, in case that the maximum output horizon is 1, the proposed algorithm can be applicable to direct adaptive GPC.

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시계열모델을 이용한 하수처리장 유입수 성상 예측 (Forecast of Influent Characteristics in Wastewater Treatment Plant with Time Series Model)

  • 김병군;문용택;김홍석;김종락
    • 상하수도학회지
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    • 제21권6호
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    • pp.701-707
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    • 2007
  • The information on the incoming load to wastewater treatment plants is not often available to apply to evaluate effects of control actions on the field plant. In this study, a time series model was developed to forecast influent flow rate, BOD, COD, SS, TN and TP concentrations using field operating data. The developed time series model could predict 1 day ahead forecasting results accurately. The coefficient of determination between measured data and 1 day ahead forecasting results has a range from 0.8898 to 0.9971. So, the corelation is relatively high. We made forecasting program based on the time series model developed and hope that the program will assist the operators in the stable operation in wastewater treatment plants.

웨이브 파이프라인 클럭 제어에 의한 1V-2.7ns 32비트 자체동기방식 병렬처리 덧셈기의 설계 (1V-2.7ns 32b self-timed parallel carry look-ahead adder with wave pipeline dclock control)

  • 임정식;조제영;손일헌
    • 전자공학회논문지C
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    • 제35C권7호
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    • pp.37-45
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    • 1998
  • A 32-b self-timed parallel carry look-ahead adder (PCLA) designed for 0.5.mum. single threshold low power CMOS technology is demonstrated to operate with 2.7nsec delay at 8mW under 1V power supply. Compared to static PCLA and DPL adder, the self-timed PCLA designed with NORA logic provides the best performance at the power consumption comparable to other adder structures. The wave pipelined clock control play a crucial role in achieving the low power, high performance of this adder by eliminating the unnecessary power consumption due to the short-circuit current during the precharge phase. Th enoise margin has been improved by adopting the physical design of staic CMOS logic structure with controlled transistor sizes.

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A Bit-level ACSU of High Speed Viterbi Decoder

  • Kim, Min-Woo;Cho, Jun-Dong
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권4호
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    • pp.240-245
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    • 2006
  • Viterbi decoder is composed of BMU(Branch metric Unit), ACSU(Add Compare Select Unit), and SMU(Survivor path Memory Unit). For high speed viterbi decoders, ACSU is the main bottleneck due to the compare-select and feedback operation. Thus, many studies have been advanced to solve the problem. For example, M-step look ahead technique and Minimized method are typical high speed algorithms. In this paper, we designed a bit-level ACSU(K=3, R=1/2, 4bit soft decision) based on those algorithms and switched the matrix product order in the backward direction of Minimized method so as to apply Code-Optimized-Array in order to reduce the area complexity. For experimentation, we synthesized our design by using SYNOPSYS Design compiler, with TSMC 0.18 um library, and verified the timing by using CADENCE verilog-XL.