• Title/Summary/Keyword: time-consistency

검색결과 819건 처리시간 0.025초

The performance and quality improvement of Lithium ion Batteries

  • Xiaoping Li
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 2004년도 전지기술심포지움
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    • pp.75-108
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    • 2004
  • The market, development and trend of Lithium ion Batteries in China are introduce briefly. Early, Chinese manufactories were busy to expand and many new battery factories have been built up. Now, the relatively large companies pay more attentions on comprehensive quality improvement, therefore the production processing and facilities have been also modified in some extent. The recent technology progresses focus on High capacity (energy density), High rate, High average voltage, High safety, High temperature properties, Long cycle life, Low temperature properties, Low self discharge, Low cost, Super-large, Super-small, Super-thin, Consistency, Customization, and Environment friendly processing, simply $H_5L_4S_3C_2E_1$. Lithium ion polymer batteries which all batteries packaged with soft lamination film are named as in China have a quick growth and emphasized here because of their advantages ins $H_5L_4S_3C_2E_1$ for which it is quite difficult to be realized at the same time. Some of research works such as listed above are introduced. The other contends related to application trend of Lithium ion batteries and projects carrying out are also included.

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에너지 시뮬레이션을 위한 서울의 표준 외기 온도 및 습도 데이터 (Standard Weather Data of Seoul for Energy Simulation)

  • 김성실;김영일
    • 설비공학논문집
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    • 제14권11호
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    • pp.897-906
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    • 2002
  • Standard temperature and absolute humidity weather correlations of Seoul for dynamic energy simulation have been developed regressing the measured data compiled by the Korea Meteorological Adminstration during a 10-year period from 1991 to 2000. The mathematical equations can generate the daily and yearly variations of outdoor weather data with consistency unlike the measured data which may show abnormal behavior, Considering that each hour of the day follows a certain yearly pattern, the correlations are developed for each hour. The derived 24 simple mathematical equations can be used for estimating outdoor temperature and humidity conditions for any arbitrary time of the year.

초소성재료의 압력성형에 관한 삼차원 유한요소해석 (3-D Finite Element Analysis of Superplastic Blow Forming)

  • 이기석;허훈
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1994년도 추계학술대회 논문집
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    • pp.55-63
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    • 1994
  • The analysis of superplastic sheet forming process is studied by the use of the finite element method using a convected coordinate system and a skew boundary condition. In the formulation, the large inelastic behavior of the superplastic material is described as incompressible, nonlinear, viscous flow. The formulation is then approximated to the finite dimensional space with the use of membrane elements, which results in algebraic linear equations. In addition to the finite element formulation, a pressure cycle control algorithm is combined in the analysis for optimization of the forming time, which deals with the maximization of the strain rate sensitivity, the protection of the thickness reduction, the consistency of the desired strain rate and improvement of formability.

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A resource-constrained job shop scheduling problem with general precedence constraints

  • Ahn, Jaekyoung
    • 경영과학
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    • 제10권1호
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    • pp.171-192
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    • 1993
  • In this paper, a rule for dispatching operations, named the Most Dissimilar Resources (MDR) dispatching rule is presented. The MDR dispatching rule has been designed to maximize utilization of resources in a resource-constrained job shop with general precedence constraints. In shown that solving the above scheduling problem with the MDR dispatching rule is equivalent to multiple solving of the maximum clique problem. A graph theoretic approach is used to model the latter problem. The pairwise counting heuristic of computational time complexity O(n$^{2}$) is developed to solve the maximum clique problem. An attempt is made to combine the MDR dispatching rule with the existing look-ahead dispatching rules. Computational experience indicates that the combined MDR dispatching rules provide solutions of better quality and consistency than the dispatching rules tested in a resource-constrained job shop.

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혼화재료의 조합사용에 따른 콘크리트의 기초물성 및 단열온도상승 특성 (Fundamental Properties and Adiabatic Temperature Rise of Concrete with the Combination of Mineral and Chemical Admixture)

  • 전충근;김종;신동안;윤기원;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.345-348
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    • 2005
  • This paper presents the result of adiabetic temperature rise and fundamental properties of concrete combining admixtures. According to results, difference of setting time with I5.5hours is observed between S-P and R-F30 mixture. Based on the adiabetic temperature rise test, 8$^{circ}C$of heat producted occurs between E-P and R-F30 mixture. is applied to estimate the temperature rising under adiabetic curing condition, which exhibits closer consistency with tested value. The function mentioned above can account for the effect of dormant period in hydration process at early stage on hydration heat production. It reveals that the consideration of placing layer based on the mixture adjustment(E-P mixture at top layer and R-F30 mixture at bottom layer) in mass concreting will contribute to reduce hydration heat as well as alleviate tensile stress discrepancy between placing layer.

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내재성 기본모델을 사용한 적용제어 시스템의 구성 (Implementation of Implicit Model Reference Adaptive Control System)

  • 허욱열;고명삼
    • 대한전기학회논문지
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    • 제32권4호
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    • pp.136-144
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    • 1983
  • In this paper, a new scheme of implicit MRAC is presented for single input single output discrete system. The MRAC can be applied to the nonminimum phase system, too. They have simple structure because the parameters of the controller are estimated directly by changing the plant output equation properly. In this scheme, the observation process is well seperated from the adaptation process, so the adaptation algorithm is derived from the exponentially weighted least square method which has fast convergence characteristics and can deal with the time varying plant. The consistency of the estimated parameter is proved. And it is also proved the whole system has the stabilizing property. The effectiveness of the algorithm and the structure is illustrated by the computer simulation of the model reference adaptive control for a third order plant. It is proposed how to select the selectable parameters in the adaptive control system from the simulation results.

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재생커널입자법을 이용한 체적성형공정의 해석 (Analysis of Bulk Metal Forming Process by Reproducing Kernel Particle Method)

  • 한규택
    • 한국기계가공학회지
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    • 제8권3호
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    • pp.21-26
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    • 2009
  • The finite element analysis of metal forming processes often fails because of severe mesh distortion at large deformation. As the concept of meshless methods, only nodal point data are used for modeling and solving. As the main feature of these methods, the domain of the problem is represented by a set of nodes, and a finite element mesh is unnecessary. This computational methods reduces time-consuming model generation and refinement effort. It provides a higher rate of convergence than the conventional finite element methods. The displacement shape functions are constructed by the reproducing kernel approximation that satisfies consistency conditions. In this research, A meshless method approach based on the reproducing kernel particle method (RKPM) is applied with metal forming analysis. Numerical examples are analyzed to verify the performance of meshless method for metal forming analysis.

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아동 후기 또래괴롭힘 참여자 역할의 안정성 및 변화와 환경적 특성과의 관계 : 주변또래의 역할을 중심으로 (Stability & Changes of Participant Roles in Bullying and Associated Environmental Characteristics : With a Focus on Peer Bystanders)

  • 서미정
    • 아동학회지
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    • 제36권4호
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    • pp.17-32
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    • 2015
  • The purpose of the present study was to explore the stability and changes of participant roles in the bullying process, namely, bullies, victims, followers, outsiders, and defenders. In addition, this study examined associated environmental characteristics of both followers and defenders in sixth graders among peer bystanders in the fifth grade. The participants consisted of 461 children from grades 5 to 6(male: 239, female: 222). Data were collected at one year intervals for two data points. The results indicated a moderate consistency in the participant roles the children take across time. Followers and outsiders tended to change differently in their roles one year later. On the other hand, defenders, bullies, and victims tended to keep the same role. The defenders group generally had higher levels of peer attachment, teacher attachment and community's supervision than the followers group. The implications for future research and intervention in bullying were also discussed.

인터넷 쇼핑몰 이용자의 의식 및 이미지 특성 분석 - 대학생을 중심으로 - (Analysis on the Consciousness and Image Character of the Internet Shopping Mall Consumer)

  • 이정;이상설
    • 산업경영시스템학회지
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    • 제28권3호
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    • pp.87-97
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    • 2005
  • This study deals with the analysis on the consciousness and image character of the internet shopping mall. As consciousness analysis result of internet shopping mall consumer, 'cheap price' and 'convenience' are evaluated high by reason that buy goods/service. 'Delivery delay' shows that deficiency of swiftness is indicated preferentially by shortcoming when the goods/service are purchased at the internet shopping mall. Consumer is prferring most 'deferred payment' with consumer's protection system of internet shopping mall. In image character of internet shopping mall, computer system speed and swiftness of reaction time, intimacy of shopping mall site design, delivery system trustability, goods/service contiguity, trustability of billing system, recognition shopping mall company, consistency about good service etc., showed high assessment, but comparative satisfaction is not high in solution at authoritativeness of personal information leakage prevention, problem occurrence.

The Effects of Superplasticizers on the Engineering Properties of Plain Concrete

  • Park, Seung-Bum
    • KCI Concrete Journal
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    • 제11권3호
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    • pp.29-43
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    • 1999
  • The effects of superplasticizers on fresh and hardened concrete were investigated. The experimental program included tests on the workability and slump loss, bleeding, setting time, air content, compressive, tensile and flexural strength, permeability, shrinkage, freeze-thaw durability and creep deformation. Properties of superplasticized concrete were compared with those of conventional and base concretes. Superplasticizers were observed to have an appreciable fluidifying action in fresh concrete. They permitted a significant water reduction while maintaining the same workability. Bleeding of superplasticized concrete was much lower than that of conventional concrete of the same consistency. This indicates that the use of superplasticizers did not affect the tendency of segregation of fresh concrete. The compressive, tensile, and flexural strengths of superplasticized concrete were significantly higher than those of conventional concrete. The permeability and drying shrinkage and creep of superplasticized concrete were less than those of conventional concrete, but there were no significant differences between base and superplasticized concrete. Compared with base concrete, non-air-entrained superplasticized concrete had slightly higher freeze-thaw durability. and superplasticized concrete with an appropriate amount of entrained air Eave even better resistance to freezing and thawing.

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