• 제목/요약/키워드: running average

검색결과 279건 처리시간 0.026초

통과의례풍속에 관한 연구 (The Study of The Traditional Rites)

  • 허성미;한재숙
    • 동아시아식생활학회지
    • /
    • 제6권3호
    • /
    • pp.411-423
    • /
    • 1996
  • The purpose of this study is to provide the basic data for Dietary Lifary Life and Culture. The frequency and percentage, x2-test and one-way ANOVA and scheffe-test for post-hoc analysis is used to evaluate our purpose by running SPSS/PC+ program. The major results are as follows: Most of the Traditional rites, Custome, and Foods are still remain as day used to be. But a few of those are changing now. That is, in the case of The Traditional Rites, peoples are not frequently participated in [The calebration of one's coming of age(2.4 out of 5.0] Regarding to the custom of Traditional Rites, most of that are the same situation with The Traditional Rites expect which have traditional supersition factor. The significant family environmental variables on satisfaction at using of professional agency bussiness for the Traditional Rites Foods are [the housewife's age(p<01], [the housewife's education(p<01] But the degree of the people's satisfaction at that is below average.

  • PDF

흡음에 의한 도시철도 곡선부 스퀼 소음저감에 관한 연구 (A Study on Squeal Noise Control by Absorption Treatment in Urban Rail Transit System)

  • 최진권;이재원;장서일
    • 한국소음진동공학회논문집
    • /
    • 제11권4호
    • /
    • pp.58-64
    • /
    • 2001
  • Sound absorbing materials are applied to the exposed surfaces of curvet subway tunnel for the reduction of curving noise level. Before the treatment, acoustical engineering simulation is performed to predict the noise level reduction for different kinds and amounts of absorbing material. The principle of geometrical acoustics is utilized to perform the simulation efficiently and accurately. The noise bevels of the inside and outside of running car body are measured to find the noise level reduction. The average noise level reduction of 8 dB has been attained. It has been shown that the simulated results are comparable to the measured ones.

  • PDF

선박용 디젤기관의 피스톤 응력해석 (Stress analysis of marine diesel engine piston)

  • 한문식;김상철
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제9권2호
    • /
    • pp.143-152
    • /
    • 1985
  • In this paper, temperature distribution and thermal stress are investigated considering engine peak pressure and the time average temperature distribution in the piston under running conditions for the marine diesel engine. The induced stress are calculated by the Finite Element Method (FEM). The results obtained are summerized as follows. 1) The results calculated by the FEM present good agreement with other numerical solution in literatures. 2) It is comfirmed that the maximum compressive stresses are induced in the part of outside wall between the piston crown and the pin bush 3) In the axial direction, the hoop stresses are changed its sign at the portion of crown near the inner wall side. 4) Large gradient of temperature is shown in the piston crown near the side wall in the axial direction, in the part between the piston crown and the pin bush in radial direction. 5) In case of stress distribution of piston wall surface in the axial direction, the hoop stress is a little greater than axial stress, and the latter is greater than the radial stress.

  • PDF

Numerical Investigation on Permanent-Magnet Eddy Current Loss and Harmonic Iron Loss for PM Skewed IPMSM

  • Lim, Jin-Woo;Kim, Yong-Jae;Jung, Sang-Yong
    • Journal of Magnetics
    • /
    • 제16권4호
    • /
    • pp.417-422
    • /
    • 2011
  • This paper presents the characteristics of PM eddy current loss and harmonic iron loss for PM step-skewed Interior Permanent Magnet Synchronous Motor (IPMSM) with concentrated windings and multi-layered PM under the running condition of maximum torque per ampere (MTPA) and flux-weakening control. In particular, PM eddy current loss and harmonic iron loss in IPMSM have been numerically computed with three-dimensional Finite Element Analysis (3D FEA), whereby IPMSM with concentrated windings and multi-layered PM has been designed to identify the optimized skew angle contributing to the reduced PM eddy current loss and torque ripples, while maintaining the required average torque. Furthermore, numerical investigation on PM eddy current loss and iron loss at MTPA and flux-weakening control has been carried-out in terms of PM step-skew.

6kW급 태양열 온수급탕 시스템의 실증실험 및 분석(제1보 실증실험) (Verification Experiment and Analysis for 6 kW Solar Water Heating System(Part 1: Verification Experiment))

  • 김진홍;김성수;최봉수;홍희기
    • 설비공학논문집
    • /
    • 제16권2호
    • /
    • pp.128-134
    • /
    • 2004
  • In order to verify and take measures against a variety of troubles which cannot be predicted in a well-controlled laboratory, it is necessary that solar system should be experimented in an actual situation during a long period. Through this experiment it can be also understood how the load pattern and operational conditions expected in a design process become different to those in the actual running, which can be applied to a new system design. We installed 6 kW solar hot water heating system with a shower facility and operated during 7 months. As a result, average 8.3 persons took a shower a day; solar fraction is 71% and total collector efficiency is 40% during the periods from March to September. We confirmed several troubles encountered in the actual situation and considered practical center-measures.

리스크 기반 테스트 케이스/테스트 세트 가치 추정 모델 (Risk-based Test Case/Test Set Value Estimation Model)

  • 권원일;김종구;권호열
    • 산업기술연구
    • /
    • 제32권A호
    • /
    • pp.125-128
    • /
    • 2012
  • In this paper, we proposed a prioritization method of test cases using a value estimation model of test sets, that are key elements for highly effective software testings as well as involve a large cost factor in software developments and maintenances. Based on previous studies, our idea includes introducing some practical factors of the test case prioritization which critically influence the value of a test case: Relative values of test sets before and after the test running, Average value of these two relative values, Severity of the defect, Risks that are covered, Frequency of use, Change related values, Systematic elicitations, etc. Finally we discussed the usefulness and the expected effects of the proposed scheme.

  • PDF

Rayleigh 페이딩 채널에서 강인한 동기 획득 시스템 (Robust Code Acquisition System in Rayleigh Fading Channel)

  • 장경운;김기채;박용완
    • 한국전자파학회논문지
    • /
    • 제11권5호
    • /
    • pp.723-730
    • /
    • 2000
  • 이 논문은 Rayleigh 페이딩 채널환경에서 가산 백색 가우시안 잡음 제거 필터를 적용한 직렬 탐색 동기 획득 방식에 대한 성능을 분석하고, 임계치를 페이딩 정도에 따라 변화시킬 수 있도록 참조 필터를 추가하여 페이딩 환경에서 강인하게 동기 획득이 이루어지도록 하였다. 성능 분석을 위해 사용된 채널 모델은 JAKE 모델이며 성능분석 결과, 제안된 동기 획득 방식이 기존의 직렬 탐색동기 획득 방식과 수신된 신호에 대한 칩별 연속 평균을 구해 페이딩에 의한 감쇄요소를 보상하는 가산 백색 가우시안 잡음 제거 필터만을 적용한 동기 획득 방식보다 낮은 신호대잡음비에서 평균 동기 획득 시간이 줄어듬을 알 수 있었다.

  • PDF

배터리 'State of Charge' 예측 알고리즘 구현 (Implementation of Battery 'State of Charge' Estimation algorithm)

  • 김용호;김대환
    • 정보통신설비학회논문지
    • /
    • 제10권1호
    • /
    • pp.27-32
    • /
    • 2011
  • These days more electric devices are implemented in car, and more accurate estimation of SoC is required. OCV with current integration and Internal Resistance is essential method of Battery SoC Estimation. In this paper we propose OCV with current integration method and compare with Internal Resistance method. In OCV with current integration method estimation error was less than average 2%, but requires more than 5 minutes to stabilize OCV. If Stop and Running conditions are change frequently, estimation error will increase. In Internal resistance Modeling method, in high SoC state, estimation error was more than 15%, and in low SoC state, estimation error was less than 8%.

  • PDF

실시간 배경갱신 및 이를 이용한 객체추적 (Real time Background Estimation and Object Tracking)

  • 이완주
    • 정보학연구
    • /
    • 제10권4호
    • /
    • pp.27-39
    • /
    • 2007
  • Object tracking in a real time environment is one of challenging subjects in computer vision area during past couple of years. This paper proposes a method of object detection and tracking using adaptive background estimation in real time environment. To obtain a stable and adaptive background, we combine 3-frame differential method and running average single gaussian background model. Using this background model, we can successfully detect moving objects while minimizing false moving objects caused by noise. In the tracking phase, we propose a matching criteria where the weight of position and inner brightness distribution can be controlled by the size of objects. Also, we adopt a Kalman Filter to overcome the occlusion of tracked objects. By experiments, we can successfully detect and track objects in real time environment.

  • PDF

시간별 신뢰도 가치를 고려한 분산전원의 최적 운영전략 (Optimal Operating Strategy of Distributed Generation Considering Hourly Reliability Worth)

  • 배인수;신동준;김진오
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제52권8호
    • /
    • pp.457-462
    • /
    • 2003
  • This paper presents an optimal operating strategy of distributed generation (DG) with reliability worth evaluation of distribution systems. Using DG for peak-shaving unit could reduce the overall system operating cost, and using DG for standby power unit could reduce the customer interruption cost. If DG operating cost is less than utility power cost in peak time, DG should be running to reduce the overall system operating cost. When customer interruption cost enlarges, however, standby power strategy may be the better operating strategy than peak-shaving strategy. Selection of whether DG should be operated for peak-shaving or for standby power, needs the accurate reliability worth evaluation and the accurate power cost evaluation. Instead of using annual average reliability worth, the concept of hourly reliability worth is introduced in this paper to determine the optimal operating decision of DG. Applying suggested hourly reliability worth, the distribution companies that possess DG could set up the optimal operating strategy of DG.