• 제목/요약/키워드: Crossover

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교차주문을 갖는 리드타임 분포의 분석 (Analysis of Lead Time Distribution with Order Crossover)

  • 김기태
    • 산업경영시스템학회지
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    • 제44권4호
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    • pp.220-226
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    • 2021
  • In supply chain, there are a variety of different uncertainties including demand, service time, lead time, and so forth. The uncertainty of demand has been commonly studied by researchers or practitioners in the field of supply chain. However, the uncertainty of upstream supply chain has also increased. A problem of uncertainty in the upstream supply chain is the fluctuation of the lead time. The stochastic lead time sometimes causes to happen so called the order crossover which is not the same sequences of the order placed and the order arrived. When the order crossover happens, ordinary inventory policies have difficult to find the optimal inventory solutions. In this research, we investigate the lead time distribution in case of the order crossover and explore the resolutions of the inventory solution with the order crossover.

Nonparametric Tests in AB/BA/AA/BB Crossover Design

  • Nam, Jusun;Kim, Dongjae
    • Communications for Statistical Applications and Methods
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    • 제9권3호
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    • pp.607-618
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    • 2002
  • Crossover design is often used in clinical trials about chronic diseases like hypertension, asthma and arthritis. In this paper, we suggest nonparametric approaches of Friedman-type rank test based on Bernard-van Elteren test and of aligned method keeping the information of blocks based on the AB/BA/AA/BB crossover design. The simulation results are presented to compare experimental error and power of several methods.

Heteroscedasticity of Random Effects in Crossover Design

  • 안철환
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2002년도 추계 학술발표회 논문집
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    • pp.79-83
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    • 2002
  • A phase III clinical trial of a new drug for neutropenia induced by chemotherapy is presented and consider adding random effects in crossover design which was used in the clinical study. The diagnostics for its heteroscedasticity based on score statistic is derived for detecting homoscedasticity of errors in crossover design. A small simulation study is peformed to investigate the finite sample behaviour of the test statistic which is known to have an asymptotic chi-square distribution under the null hypothesis.

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Usefulness of AB/BA/AA/BB Crossover Design

  • Nam, Jusun;Kim, Dongjae
    • Communications for Statistical Applications and Methods
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    • 제10권1호
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    • pp.115-123
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    • 2003
  • In this paper, we discuss the usefulness of AB/BA/AA/BB crossover design sense of sample size. The result is that the AB/BA/AA/BB crossover design is more economical than AB/BA one if large carryover effect exists and so is it in the comparison with completely randomized design within-subject correlation is large.

수도권 전차선로 교차개소에 대한 고찰 (A study on a crossover on overhead catenary system in the urban transit)

  • 이기원;권삼영;김주락;창상훈
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(III)
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    • pp.507-512
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    • 2003
  • Even if tracks cross each other, a train has to maintain a good current collection. Where catenary cross each other, it is called a crossover. Based on the cause analysis for a breakdown accident of pantograph occurred in the crossover on Ansan-line, a theoretical background and recommendation for the installation rule of a crossover are presented in the paper.

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병렬 유전 알고리즘 기반 meta-유전 알고리즘을 이용한 교차율과 돌연변이율의 최적화 (Optimization of Crossover and Mutation Rate Using PGA-Based meta-GA)

  • 김문환;박진배;이연우;주영훈
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 추계학술대회 및 정기총회
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    • pp.375-378
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    • 2002
  • In this paper we propose parallel GA to optimize mutation rate and crossover rate using server-client model. The performance of GA depend on the good choice of crossover and mutation rates. Although many researcher has been study about the good choice, it is still unsolved problem. proposed GA optimize crossover and mutation rates trough evolving subpopulation. In virtue of the server-client model, these parameters can be evolved rapidly with relatively low-grade

유전알고리즘을 이용한 보수계획수립에 관한 연구 (Maintenance Scheduling using A Genetic Algorithms with a new crossover operator)

  • 정정원;김정익
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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    • pp.332-334
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    • 1998
  • Maintenance scheduling is one of mid-term scheduling problems of power systems. There have been many methods for this problem, but there is no effective way to treat all the generators simultaneously except evolutionary algorithms. In this paper, we apply GA to the maintenance scheduling problem. And we proposed new crossover operator(BOX type crossover) to improve searching ability of GA. Satisfactory results are obtained by GA with proposed crossover operator.

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원자로냉각재계통 중간배관과 동적거동 구속장치와의 접촉으로 인한 배관 건전성 평가 (Evaluation of Structural Integrity of Crossover Leg Piping System with Dynamic Whip Restraints)

  • 양준석;김범년;오상권;오창훈;이대희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집A
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    • pp.636-643
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    • 2001
  • Interference between the crossover leg of the reactor coolant system (RCS) and the pipe whip restraints (PWR) has brought a degradation issue of the integrity of the Reactor Coolant System in Westinghouse type nuclear power plants (NPPs) of Korea. According to the gap Inspect ion carried out during planned overhaul (Year 2000), interference between the crossover leg and the PWR was found in each RCS loop. This plant has had the high vibration problem on the RC pump 'B'. The reason for the high vibration in the RC pump 'B' had been massively surveyed and it was found that the crossover leg of RCS contacted with the PWR in hot condition. Since the contact between the crossover leg and the PWR changes the dynamic characteristics of the piping system for the RCS, this is considered as one reason for the high vibration. And a possibility of overstress on the crossover leg due to the contact with the PWR should be evaluated. Through performing RCS integrity analyses, subsequent actions were initiated to increase the gap between those parts. As the results of the appropriate separation between two parts, it was reported that there was no unusual noise or vibration during plant heat-up. In this paper, the evaluations for the gap between the crossover leg and the PWR and the structural integrity due to loop binding is described.

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대중문화의 크로스오버와 콜라보레이션 유행에 따른 한국 공포영화에서의 가능성 (A Study on the Possibilities in Korean Horror Movies Due to Popular Culture Crossover and Collaboration Trends)

  • 안일환
    • 한국엔터테인먼트산업학회논문지
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    • 제15권4호
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    • pp.31-43
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    • 2021
  • 요즘 시대의 화두는 바로 혁신과 융합이다. 혁신을 통해 융합이 탄생하고 융합을 통해 혁신이 이루어지니 융합이 곧 혁신이라고도 볼 수 있다. 대중문화에서 융합이라는 개념으로 쓰이는 크로스오버와 콜라보레이션(*크로스오버로 통칭)은 서로 다른 장르나 분야 간의 결합, 통합을 의미하며 최근 영화나 음악 등 다양한 분야에서 사용되고 있다. 크로스오버의 활용은 타 분야와의 경계를 허물고 자유롭고 다양한 시도를 통해 새로운 작품을 창조해 내는 데 도움을 준다. 이에 본 연구에서는 대중문화의 융합, 즉 크로스오버를 한국의 공포영화 장르와 연계하여 분석해본다. 현재 한국 공포영화는 90년대에서 2000년대 초반까지 인기를 끌다가 현재는 연속된 흥행 부진으로 인해 소수의 작품만이 나오는 실정이다. 하지만 본 연구 결과 한국 공포영화에서도 이미 크로스오버 시도는 시작되었고 몇몇 흥행한 작품들에서 크로스오버의 흔적이 강하게 발견되었다. 본 연구에서는 거기에서 더 나아가 <어벤저스> 같은 캐릭터 콜라보레이션까지 적용해서 한국 공포영화의 새로운 방향성까지 제시해본다.

고분자 연료전지 스택에서 질소 크로스오버 특성에 관한 연구 (Characterization of Nitrogen Gas Crossover in PEM Fuel Cell Stacks)

  • 백경돈;김민수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2227-2230
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    • 2008
  • Crossover of nitrogen from cathode to anode is inevitable in typical membranes used in PEM fuel cells. This crossovered nitrogen accumulates in anode recirculation system and excessive buildup of nitrogen in the recirculating anode gas lowers the hydrogen concentration and finally affects the performance of fuel cell stacks. In this study, characterization of nitrogen gas crossover was investigated in PEM fuel cell stacks. The mass spectroscopy (MS) has been applied to measure the amount of the crossovered nitrogen at the exit of anode. Results show that anode and cathode stoichiometric number ($SR_c$) have a big effect of nitrogen crossover.

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