• Title/Summary/Keyword: due-date

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Structural Analysis for Building Structures reflecting Differential Column Shortening based upon Construction Sequence (시공 공정에 따른 건축 구조물의 구조해석 및 수직부재의 부등변형)

  • 조상규;이형우;최창식
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.333-341
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    • 1998
  • The general method of structural analysis for building structures has been based upon the assumption that all dead loads are imposed on a building simultaneously throughout the entire structure. In reality, buildings are built floor by floor or a few floors at a time. The construction dead load is applied gradually onto the structure as the structure is being erected. The prevailing commercial software for structural analysis used to date have resulted in the representation of inaccurate structural behaviors. The actual construction sequence and the loading of the structure ere not properly represented in the analysis. This paper identifies the source of the errors and develops the algorithm to account for the differential column shortening due to construction dead load based upon a given construction sequence

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An Investigation of the Effect of Re-entrance to the Same Station in a Job Shop Scheduling (Job Shop Scheduling에서 동일한 작업장에 대한 재투입 허용이 미치는 영향분석)

  • 문덕희;최연혁;신양우
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.47
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    • pp.125-138
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    • 1998
  • In this paper, we investigate the effect of re-entrance to the same work station in a job shop with multiple identical machines. System A is defined as the system in which re-entrance is not permitted, and system B is defined as the system in which re-entrance is permitted. By the analytical result of the queueing network, we find that the two systems have the same queue length distributions and utilizations under FIFO dispatching rule when all parameters are same. Simulation models are developed for various comparisons between the two systems, and simulation experiments are conducted for the combinations of five dispatching rules, two average workloads and two due date allowances. Five performance measures are selected for the comparison. The simulation results show that permitting re-entrance affects for some combinations of system environments.

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Historical study of 濟衆入效方 -focusing on 交效散 (『제중입효방(濟衆立效方)』에 관한 의사학적 고찰 - 교효산(交效散)을 중심으로 -)

  • Lee, Duk Ho;Kim, Hong-kyoon;Ahn, Sang Woo
    • The Journal of Korean Medical History
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    • v.21 no.2
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    • pp.29-39
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    • 2008
  • "濟衆立效方" is the oldest Koryo dynasty medical document known to date. Despite its historical importance, due to the absence of its original copy, its true characters could not be understood. Through comparison of the many documents that cited 濟衆立效方, it could be found that 濟衆立效方 can be classified into two parts based on its contents and form. In Chinese medical texts, neither the name 交效散 nor any similar prescription is mentioned. 濟衆立效方 was the first in suggesting the usage of pine needles and salt for fomentation and not for internal use. Thus 交效散 can be thought of as the oldest indigenous prescription preserved in Korean history. 濟衆立效方 conveys records of the combination of the ancient origin pine needle fomentation and the creative addition of salt.

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Quasi Assignment Algorithms in Job Shops

  • Byeon Eui-Seok;Lee Jang-Yong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2002.05a
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    • pp.704-708
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    • 2002
  • Production scheduling has been one of the most critical issues in a manufacturing environment Job-shop scheduling problems(JSP) are well know from the standpoint of production planning and operations control in this research scheduling against due date is a measure of performance and the objective is minimizing total weighted tardiness This paper presents an idea of decomposition of the problem and shows robustmess of the schedule under various disturbances along with exact and approximation methods. The proposed method can indeed handle shop disturbances more effectively when compared with traditional and dynamic scheduling methods.

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Evaluation of drug interventions for the treatment of sleep disorders in children with autism spectrum disorders: a systematic review

  • Jenabi, Ensiyeh;Ataei, Sara;Bashirian, Saeid
    • Clinical and Experimental Pediatrics
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    • v.62 no.11
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    • pp.405-409
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    • 2019
  • A structured review study of drug interventions on sleep disorders in patients with autism spectrum disorders (ASD) has not been published to date. This systematic review aimed to investigate drug interventions for the treatment of sleep disorders in children with ASD. The Web of Science, PubMed, and Scopus databases were searched until March 2019. Study quality was assessed using the Delphi checklist. Due to the heterogeneity of the findings, a meta-analysis was not possible. Drug interventions for the treatment of sleep disorders in patients with ASD included melatonin, atomoxetine, and risperidone. Atomoxetine had no effect on sleep disorders in patients with ASD. A total of 10 studies were reviewed. Melatonin appears to be useful for the treatment of sleep problems in patients with ASD, but further studies are needed to determine the effects of other drugs.

Ranking Dispatching Rules in the Job Shop with Unbalanced Machine Workloads (설비 작업부하가 불균형한 Job Shop에서 할당규칙의 순위)

  • 배상윤
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.50
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    • pp.161-170
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    • 1999
  • This paper evaluates forty different dispatching rules with respect to twenty different performance measures of job shop scheduling under seven levels of workload imbalance. Computer simulation is used as a tool to determine rankings of the dispatching rules for a given workload imbalance. The experiments results show rankings of dispatching rules are different in the job shop with unbalanced machine workloads. As variations of workload imbalance increase from 7% to 78%, the performance of dispatching rules is gradually deteriorated in measure related to completion time and due date. These results guide scheduling practitioners not only to choosing dispatching rules but also to developing the model of facility investment for workload balance, when there are different levels of workload imbalance.

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A Study on the Body Welding Operation Scheduling Considering the Assembly Line's Input Sequence in Construction Equipment Manufacturing (건설기계 조립 라인 투입 순서를 고려한 제관 공정 생산 스케줄링에 관한 연구)

  • Kim, Ki-Dong;Choi, Ho-Sik
    • Journal of Industrial Technology
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    • v.27 no.A
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    • pp.69-76
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    • 2007
  • The body of an excavator, one sort of the construction equipment, consists of mainframe part, track frame part, boom part and arm part. The all parts are manufactured in the body welding operation. The scheduling in the body welding operation of a construction equipment manufacturing is to take all the various constraints into consideration. The offset time, due date, daily capacity of operations, daily jig's capacity, precedence relation, outsourcing, alternative resource and all of the shop floor environment should be considered. An APS(Advanced Planning & Scheduling) system is a proper and efficient system in such circumstance. In this paper, we present an APS system, the optimal scheduling system for the construction equipment manufacturing specifically for the body welding operation, using ILOG Solver/Scheduler. ILOG Solver/Scheduler is a general purposed commercial software which supports to find a feasible or optimal solution using object oriented technique and constraints satisfaction programming, given constraints and objectives.

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Semiconductor Backend Scheduling Using the Backward Pegging (Backward Pegging을 이용한 반도체 후공정 스케줄링)

  • Ahn, Euikoog;Seo, Jeongchul;Park, Sang Chul
    • Korean Journal of Computational Design and Engineering
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    • v.19 no.4
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    • pp.402-409
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    • 2014
  • Presented in this paper is a scheduling method for semiconductor backend process considering the backward pegging. It is known that the pegging for frontend is a process of labeling WIP lots for target order which is specified by due date, quantity, and product specifications including customer information. As a result, it gives the release plan to meet the out target considering current WIP. However, the semiconductor backend process includes the multichip package and test operation for the product bin portion. Therefore, backward pegging method for frontend can't give the release plan for backend process in semiconductor. In this paper, we suggest backward pegging method considering the characteristics of multichip package and test operation in backend process. And we describe the backward pegging problem using the examples.

A AGV time-oriented Job Dispatching Methodology for Preventing the Tardiness (납기지연시간 단축을 위해 AGV 시간을 고려한 작업할당 방법)

  • Kim, Geun-Hyung;Ko, Hyo-Heon;Baek, Jun-Geol
    • Journal of the Korea Safety Management & Science
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    • v.13 no.4
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    • pp.125-137
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    • 2011
  • Customers are generally requiring a variety of products, earlier due date, and lower price. A manufacturing process needs the efficient scheduling to meet those customer's requirements. This study proposes the novel algorithm named MJA(Minimum Job completion time and AGV time) that increases the performance of machines and AGV(Automated Guided Vehicles) in many kinds of job types. MJA optimizes the bottleneck of machines and efficiency of AGV with considering two types of dispatching at the same time. Suggested algorithm was compared with existing heuristic methods by several simulations, it performed better for reducing the time of tardiness.

A Study on the Priority Area Selection for Updating FDB Attributes using MODIS Product (MODIS Product를 활용한 FDB 속성 갱신 대상지역 선정 연구)

  • Park, Wan-Yong;Eo, Yang-Dam;Kim, Yong-Min;Kim, Chang-Jae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.1
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    • pp.65-73
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    • 2013
  • FDB(Feature DataBase) attributes have been produced by using the resource data prior to the year 2002. Due to this reason, the attributes need to be updated to the up-to-date ones. In this regards, this study focuses on the way of finding areas whose attributes need to be updated. Forest and crop classes were chosen as target classes among FDB features. MODIS Landcover data and FDB are, first, compared to detect the changed forest and crop areas from 2001 to 2008. Then, vegetation vitality changes are analyzed using MODIS annual NDVI data. Based on the change detection and the vegetation vitality analysis, the index of area selection for updating FDB attributes is proposed in this study.