• Title/Summary/Keyword: basic load

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PSTCP : A Tool to Evaluate Power System Transfer Capability (전력계토의 수송능력 평가 프로그램 개발에 관한 연구)

  • Yu, Su-Hyeon;Jeong, Jong-Hun;Jeong, Min-Hwa;Lee, Byeong-Jun;Song, Gil-Yeong;Sin, Yeong-Cheol;Kim, Yeong-Seon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.7
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    • pp.872-880
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    • 1999
  • This paper presents an algorithm that can calculate the evaluation index of power system from the transfer capability point of view. The algorithm adopts a successive linear programming skill to solve an optimal solution. Two indices which are transfer margin index and economic matching index have been developed. Prior to calculating these indices, Maximum Load supplying Capability(MLSC) and Economic Load Supplying Capability(ELSC) are utilized as basic data. For man-machine interface, graphical user interface has been implemented so that an unified software package PSTCP(Power System Transfer Capability Program) has been developed. KEPCO systems planned up to 2006 year have been tested to show effectiveness and usefulness of the PSTCP for power system planning stages.

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- Review on Reliability of Observational Methods to Evaluate Postural Load - (관찰적 작업자세 평가 기법의 관찰 신뢰도에 관한 고찰)

  • Lee In Seok
    • Journal of the Korea Safety Management & Science
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    • v.6 no.3
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    • pp.77-86
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    • 2004
  • Observational methods to evaluate postural load have an intrinsic week point that is the problem of reliability in observing postures subjectively, although they have been widely used in assessing risk factors of work-related musculoskeletal disorders in the industry. In this study, observational reliability was discussed based on reviewing several previous studies. Practical guidelines was presented to reduce the observational errors when using video recording for the assessment of risk factors. In addition, previous studies on observational reliability were summarized and analyzed according to body parts to be observed, media for observation, objective measures, analysis, statistics, etc. It is expected that this basic study can be used to increase the applicability and accuracy of the observational methods.

Dynamic Simulation of Annual Energy Consumption in an Office Building by Thermal Resistance-Capacitance Method

  • Lee, Chang-Sun;Choi, Young-Don
    • International Journal of Air-Conditioning and Refrigeration
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    • v.6
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    • pp.1-13
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    • 1998
  • The basic heat transfer process that occurs in a building can best be illustrated by an electrical circuit network. Present paper reports the dynamic simulation of annual energy consumption in an office building by the thermal resistance capacitance network method. Unsteady thermal behaviors and annual energy consumption in an office building were examined in detail by solving the simultaneous circuit equations of thermal network. The results are used to evaluate the accuracy of the modified BIN method for the energy consumption analysis of a large building. Present thermal resistance-capacitance method predicts annual energy consumption of an office building with the same accuracy as that of response factor method. However, the modified BIN method gives 15% lower annual heating load and 25% lower cooling load than those from the present method. Equipment annual energy consumptions for fan, boiler and chiller in the HVAC system are also calculated for various control systems as CAV, VAV, FCU+VAV and FCU+CAV. FCU+CAV system appears to consume minimum annual energy among them.

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A Quantitative Linguistic Study on the Functional load of Phonemes in Standard Korean (한국어 음소의 기능부담량 - 계량 언어학적 연구)

  • Jin Nam-Taek
    • MALSORI
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    • no.25_26
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    • pp.65-92
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    • 1993
  • Not all linguistic units are of equal importance in the functioning of language. The present study aims to examine He functional load of phonemes in standard Korean, To achieve this goal, B analysed continuous texts selected from the textbooks of elementary school on a personal computer. The total number of syllables studied in this thesis is 101,637. The characteristics of the Korean syllable structures are as follows. 1) In a syllable head, /n/ occurs most frequently. 2) The frequencies of syllables with an onset are much higher than those with no onset ( 85% : 15% ), 3) In a syllable head, obstruents are preferred because their consonantal strength are great, (57%) 4) In a syllable nucleus, /a/ occurs most frequently. 5) The rate of occurrence of the monophthongs is 90.2%, and that of the diphthongs is 9.8%. Especially the three basic vowels(/i,a,u/) occur at the rate of 46.6%. 6) In a syllable coda, /n/ occurs most frequently. 7) The open syllables are favored (open syllable 68.7%, closed syllable 31.3%).

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Flexible Multibody Dynamic Model of a Maglev Vehicle Bogie (자기부상열차 대차 유연 다물체 모델)

  • Kim, Ki-Jung;Han, Hyung-Suk;Lee, Nam-Jin;Kim, Bong-Sub
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.1207-1212
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    • 2009
  • The flexible multibody dynamic model of an EMS-type Maglev vehicle is necessary in design stage to predict its behavior, load history and levitation performance. Especially in EMS-type Maglev vehicle, the body flexibility of its bogie with electromagnets affects the levitation performance because its feedback control system is more sensitive to vibration of bogie structure. The flexible multibody dynamic model of a 1/2 Maglev vehicle under test is presented. The basic modeling procedure is almost the same as in other applications. However, the feedback control system model unique in EMS-type maglev vehicle must be included in the model. With the model proposed in this study, the dynamic behavior, load history and levitation performance are more precisely predicted. This model could realize the virtual prototyping in EMS-type Maglev vehicle area.

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A Study on Stabilization of Container Cranes Using an Optimal Modulation Controller (최적 변조제어기를 이용한 컨테이너 크레인의 안정화에 관한연구)

  • 허동렬
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.5
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    • pp.630-636
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    • 1999
  • In this paper in optimal modulation controller for position control and anti-sway of container crane systems is designed by a recursive algorithm that determines the state weighting matrix Q of a linear quadratic performance. The optimal modulation controller is based on optimal control. The basic feature of the recursive algorithm is the reduction of the number of iterations as well as minimization of the calculations involved So in order to obtain a mathematical model which rep-resents the equation of motion of the trolley and load Lagrange equation is used. The optimal modulation controller has been verified and simulated to show that it is robust when a load dis-turbance is applied and a reference is changed.

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A Study on the Improvement of Bearing Capacity Prediction Equation for Auger-drilled Piling (매입말뚝공법의 지지력 예측식 개선에 관한 연구)

  • 최도웅;한병권;서영화;조성한
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.10a
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    • pp.382-389
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    • 2002
  • Recently, auger-drilled piling has been widely used in urban area to reduce the air pollution and noise. But this construction method that its basic theory was introduced from Japan may be changed depending on the each piling company and construction field condition. Therefore, the design code and management method for auger-drilled piling is not defined yet. Especially, the lack of research on the bearing capacity of auger-drilled piling leads to the absence of rational bearing capacity prediction equation. This paper presents the optimum design code and economical construction method of the auger-drilled piling by proposing the new bearing capacity prediction equation based on the site specific soil types and construction conditions. In this paper, existing bearing capacity prediction equations and current pile load tests were compared. And the end bearing capacity and skin friction characteristics were also analyzed by comparing the results of CAPWAP. From the results of analysis, a reliable bearing capacity prediction equation considered soil types is proposed.

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A 3V-50MHz analog CMOS continuous time current-mode filter with a negative resistance load

  • 현재섭;윤광섭
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.7
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    • pp.1726-1733
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    • 1996
  • A 3V-50MHz analog CMOS continuous-time current-mode filter with a negative resistance load(NRL) is proposed. In order to design a current-mode current integrator, a modified basic current mirror with a NRL to increase the output resistance is employed. the inherent circuit structure of the designed NRL current integrator, which minimizes the internal circuit nodes and enhances the gain bandwidth product, is capable of making the filter operate at the high frequency. The third order Butterworth low pass filter utilizing the designed NRL current integrator is synthesized and simulated with a 1.5.mu.m CMOS n-well proess. Simulation result shows the cutoff frequency of 50MHz and power consumption of 2.4mW/pole with a 3V power supply.

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A basic study for development of SMART form for beams (SMART 보 거푸집 개발 기초연구)

  • Kim, Gyeongju;Lim, Chaeyeon;Kim, Sunkuk
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.11a
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    • pp.203-204
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    • 2014
  • Unlike other members, beams have various cross-sections and they have an important role of delivering the load of slabs. A beam form neighbors the columns and slabs, which makes it difficult to be installed. In a conventional way to exclusively use the form after concrete pouring, the form and a support should be both removed. Then, the support should reinstalled to sustain the stripping time of form, resulting in a structural issue. To solve such structural problem, the study proposes SMART beam form that uses filler panels and supports for filler. The floor filler panels and supports for filler are not removed after concrete curing, to conform to the stripping time of supports. Thus, any structural problem such as cracks and reduction of compressive strength owing to the gap of load bearing capacity can be prevented. The study results will be used as cases for studies on productivity analyses.

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Fatigue Life Evaluation of the Plastic Gear (플라스틱 기어의 피로수명 평가 및 수명 예측)

  • Chong Tae Hyong;Kang Sung Kyu;Ha Young Wook
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2005.05a
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    • pp.239-245
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    • 2005
  • Through the fatigue test of plastic gears using polyacetal polymer, this research aims at providing basic data for not only specifying operation conditions of plastic gears, but also designing dimensions of plastic gears with giving fatigue life and the estimated equation of fatigue life of plastic gears. That is, from the fatigue life curves, the estimated equation of fatigue life of plastic gears is taken out. For the estimated equation of fatigue life of plastic gears, this research provides two test methods; one is preserving non-limited temperature of tooth flank, the other is preserving limited temperature of tooth flank. As results, how the temperature of tooth flank affects the fatigue life is shown. In addition, based on the endurance limit, the essential factors of the unit load and K-factor are determined, which are needed in the design of gear by bending strength and surface durability.

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