• Title/Summary/Keyword: Excel-solver

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A connection method of LPSolve and Excel for network optimization problem (네트워크 최적화 문제의 해결을 위한 LPSolve와 엑셀의 연동 방안)

  • Kim, Hu-Gon
    • Journal of Korea Society of Industrial Information Systems
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    • v.15 no.5
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    • pp.187-196
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    • 2010
  • We present a link that allows Excel to call the functions in the lp_solve system. lp_solve is free software licensed under the GPL that solves linear and mixed integer linear programs of moderate size. Our link manages the interface between Excel and lp_solve. Excel has a built-in add-in named Solver that is capable of solving mixed integer programs, but only with fewer than 200 variables. This link allows Excel users to handle substantially larger problems at no extra cost. Futhermore, we introduce that a network drawing method in Excel using arc adjacency lists of a network.

Land Generated Waste Load Unit Estimation Based on Land Use Map with LP Optimization (LP 최적화에 의한 토지피복도 기반 토지계 발생부하 원단위 산정)

  • Park, Kyung Ok;Lee, Chang Hee
    • Journal of Wetlands Research
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    • v.18 no.3
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    • pp.226-231
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    • 2016
  • Land Generated Waste Load Unit(LGWLU) estimation based on land use data is required to understand the impact of land use on water quality. The method of estimating LGWLU based on the monitoring data requires a lot of time and manpower. In this study, we propose a method of land pollution unit load estimation based on land use data with LP optimization. Optimization is the process to obtain the best possible optimal solution in a given condition. This study carried out optimization by using excel solver in Microsoft Excel. This study derived LGWLU of BOD, T-N, T-P in Gongju-Si and Seocheon-Gun by using the 2012 land use map made by ministry of environment based on 2010 satellite image. This study about LGWLU estimation is expected to be able to determine more clearly the water pollution caused by land use changes.

Replicating the chemical composition of the binder for restoration of historic mortars as an optimization problem

  • Miriello, D.;Lezzerini, M.;Chiaravalloti, F.;Bloise, A.;Apollaro, C.;Crisci, G.M.
    • Computers and Concrete
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    • v.12 no.4
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    • pp.553-563
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    • 2013
  • The present study aims to show how the problem of reproducing, as closely as possible, binders of historic mortars by mixing raw materials which are commercially available, can be formulated as a linear optimization problem. The study points out that by mixing five standard raw materials (end-members) it is possible to obtain mortar binders with the almost same chemical compositions of those determined on the historic and archaeological mortar samples studied in some recent scientific papers. An advanced function of the Microsoft Excel spreadsheet, the Solver add-in, was used for the calculation of the right amount of each raw material to be mixed for producing the new binders. This approach could be useful to provide an optimal solution in the process of restoration of ancient monuments, where it is necessary to replace the historic mortars with new highly compatible repair mortars.

An Integer Programming Model for a Complex University Timetabling Problem: A Case Study

  • Prabodanie, R.A. Ranga
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.141-153
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    • 2017
  • A binary integer programming model is proposed for a complex timetabling problem in a university faculty which conducts various degree programs. The decision variables are defined with fewer dimensions to economize the model size of large scale problems and to improve modeling efficiency. Binary matrices are used to incorporate the relationships between the courses and students, and the courses and teachers. The model includes generally applicable constraints such as completeness, uniqueness, and consecutiveness; and case specific constraints. The model was coded and solved using Open Solver which is an open-source optimizer available as an Excel add-in. The results indicate that complicated timetabling problems with large numbers of courses and student groups can be formulated more efficiently with fewer numbers of variables and constraints using the proposed modeling framework. The model could effectively generate timetables with a significantly lower number of work hours per week compared to currently used timetables. The model results indicate that the particular timetabling problem is bounded by the student overlaps, and both human and physical resource constraints are insignificant.

Mathematical Model for Liner Shipping Alliance Problem (컨테이너 정기선 선사의 전략적 제휴를 위한 수리적 모형 연구)

  • Chung, Ki-ho
    • Management & Information Systems Review
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    • v.33 no.5
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    • pp.85-95
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    • 2014
  • This paper suggested an efficient mathematical model for strategic alliance of liner shipping companies. Even though a few previous research papers proposed the mathematical models for container slot chartering and allocation under liner shipping, those models were nonlinear and very difficult to solve. So their models had limits to apply them to real world problems. On the other hand, the model suggested in this paper is easy to solve and apply to real world problems because it is a integer linear programming model. This paper tried to apply the model to the same example problem as used in existing research paper. Excel add-in program, Premium Solver Platform was used to solve the problem and the optimal allocation and slot chartering for containers were able to be found easily. The result also showed that the total container shipping cost for applying the strategic alliance model was reduced compared to non-strategic alliance model.

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An Optimization Model for an Production-Distribution Planning with Consideration of a Transportation Time (운송시간을 고려한 생산-분배계획을 위한 최적화모델)

  • Lim, Seok-Jin;Jeong, Suk-Jae
    • Journal of the Korea Safety Management & Science
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    • v.10 no.1
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    • pp.139-144
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    • 2008
  • Recently, a multi-facility, multi-product and multi-period industrial production-distribution planning problem has been widely investigated in Supply Chain Management (SCM). One of the key issues in the current SCM research area involves reducing both production and distribution costs. We have developed an optimization model to tackle the above problems under the restricted conditions such as transportation time and a zero inventory. Computational experiments using commercial tool Ms-Excel Solver show that the real size problems we encountered can be solved in reasonable time. The model can be used to decide an appropriate production-distribution planning problem in SCM research area.

Optimal design of offshore production considering market demand (시장 수요를 고려한 Offshore Production의 최적화 설계)

  • Kim, Chang-Su;Kim, Si-Hwa
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2014.10a
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    • pp.53-55
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    • 2014
  • Offshore 에서의 oil & gas 생산은 해상이라는 환경으로 인한 고유의 특성 때문에 항상 다수의 변수들에 영향을 받으며, 막대한 비용이 소요되기 때문에 비용을 최소화하며, 비용 대비 수익을 최대화시키기 위한 optimal design이 필수이다. 본 논문은 가상의 offshore plant와 이에서 생산된 oil의 수요지들을 설정하여 시장수요에 따른 offshore 생산의 최적화 문제를 연구대상으로 하며, 다수의 offshore oil fields를 보유한 major oil company가 당면할 수 있는 offshore production에 관한 문제를 일반화하여 정의하고, 이윤을 극대화시킬 수 있는 최적화 모형을 혼합정수계획모형(mixed integer programming)으로 정식화 하였다. 최적화 모형의 해는 Microsoft office excel solver를 통해 구하였으며 그 계산실험의 결과를 요약하여 보고한다.

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A Study on the Stock Assessment and Management Implications of the Hairtail, Trichiurus lepturus Linne in Korean Waters 1. Estimation of Population Ecological Characteristics of the Hairtail, Trichiurus lepturus Linne in Korean Waters (한국 연근해 갈치의 자원평가 및 관리방안 연구 1. 한국 연근해 갈치의 자원생태학적 특성치 추정)

  • ZHANG Chang-Ik
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.5
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    • pp.567-577
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    • 1996
  • This study is to estimate population ecological parameters, including growth parameters, survival rates, instantaneous coefficients of natural and fishing mortalities, and age at first capture, as well as growth rates at age of the hairtail, Trichiurus lepturus Linne in Korean waters. For describing the growth of the hairtail, three growth models were fitted, and the von Bertalanffy growth model was adopted for the purpose of the further stock assessment work. The von Bertalanffy growth parameters estimated from a nonlinear regression using EXCEL Solver were $L_\infty=46.01cm$, K=0.3868, and $t_0=-0.3220$. Annual survival rate (S) of the hairtail was estimated to be 0.277 (variance=0.00035) and the instantaneous coefficient of natural mortality (M) was estimated to be 0.441/year. Instantaneous coefficient of fishing mortality (F) for the recent years was calculated as 0.843/year, implying an impact from fishing about two times greater than that of natural mortality. The age at first capture $(t_c)$ was estimated to be 0.787 years, which is much younger age than $50\%$ mature age. Finally, the growth rates at age were estimated.

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