Inventory Sharing with Transshipment: Impacts of Demand Distribution Shapes and Setup Costs

Lot sizing problem in production planning aims to optimize production costs (processing, setup and holding cost) by fulfilling demand and resources capacity costraint. The Capacitated Lot sizing Problem (CLSP) model aims to balance the setup costs and inventory costs to obtain optimal total costs. The object of this study was a plastic component manufacturing company. This study use CLSP model, considering process costs, holding costs and setup costs, by calculating product cycle and setup time. The constraint of this model is the production time capacity and the storage capacity of the finished product. CLSP can reduce the total production cost by 4.05% and can reduce setup time by 46.75%. Keyword: Lot size, CLSP, Total production cost.

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Reliability and Accuracy of Bootstrap and Monte Carlo Methods for Demand Distribution Modeling

Volume 9: 23rd International Conference on Design Theory and Methodology; 16th Design for Manufacturing and the Life Cycle Conference ◽

10.1115/detc2011-47496 ◽

2011 ◽

Author(s):

Swithin S. Razu ◽

Shun Takai

Keyword(s):

Monte Carlo ◽

Product Development ◽

Conjoint Analysis ◽

New Product Development ◽

Demand Uncertainty ◽

New Product ◽

Product Development Process ◽

Choice Data ◽

Product Concept ◽

Demand Distribution

Estimation of demand is one of the most important tasks in new product development. How customers come to appreciate and decide to purchase a new product impacts demand and hence profit of the product. Unfortunately, when designers select a new product concept early in the product development process, the future demand of the new product is not known. Conjoint analysis is a statistical method that has been used to estimate a demand of a new product concept from customer survey data. Although conjoint analysis has been increasingly incorporated in design engineering as a method to estimate a demand of a new product design, it has not been fully employed to model demand uncertainty. This paper demonstrates and compares two approaches that use conjoint analysis data to model demand uncertainty: bootstrap of respondent choice data and Monte Carlo simulation of utility estimation errors. Reliability of demand distribution and accuracy of demand estimation are compared for the two approaches in an illustrative example.

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Produktionskennlinien für Arbeitssysteme mit Rüstzyklen*/Increasing output by setup optimized sequencing

wt Werkstattstechnik online ◽

10.37544/1436-4980-2017-04-86 ◽

2017 ◽

Vol 107 (04) ◽

pp. 282-287

Author(s):

F. Engehausen ◽

H. Prof. Lödding

Keyword(s):

Setup Times ◽

Trade Off ◽

Setup Costs ◽

Sequence Dependent ◽

Sequence Dependent Setup ◽

Dependent Setup Times ◽

Sequence Dependent Setup Times

Viele Unternehmen nutzen Rüstzyklen, um Rüstaufwände bei besonders reihenfolgeabhängigen Rüstzeiten zu verringern und nehmen dafür höhere Bestände und Durchlaufzeiten in Kauf. Rüstzykluskennlinien gestatten es, diesen Zielkonflikt zu modellieren und übersichtlich darzustellen. Dieser Fachartikel erklärt, welche Größen einen besonderen Einfluss auf den Verlauf der Kennlinien haben und wie diese in die Modellierung integriert werden.   In the case of sequence-dependent setup times many companies use setup cycles to reduce setup costs accepting higher WIP levels and throughput times. Logistic operating curves for setup cycles enable the illustration of this trade-off and a logistic positioning. This article explains which variables have a particular influence on the characteristics of the operating curves and how they are integrated into the modeling.

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The Newsboy Problem With Price-Dependent Demand Distribution

IIE Transactions ◽

10.1080/07408178808966166 ◽

1988 ◽

Vol 20 (2) ◽

pp. 168-175 ◽

Cited By ~ 171

Author(s):

AMY HING-LING LAU ◽

HON-SHIANG LAU

Keyword(s):

Newsboy Problem ◽

Demand Distribution ◽

Dependent Demand

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Model Integrasi Penjadwalan Batch dan Penjadwalan Preventive Maintenance dengan Kriteria Minimisasi Biaya Simpan, Biaya Setup, Biaya Pm, serta Biaya Rework pada Mesin Stabil

ComTech Computer Mathematics and Engineering Applications ◽

10.21512/comtech.v5i1.2634 ◽

2014 ◽

Vol 5 (1) ◽

pp. 397

Author(s):

Zahedi Zahedi

Keyword(s):

Preventive Maintenance ◽

Batch Scheduling ◽

Problem Instance ◽

Production Schedule ◽

Batch Production ◽

Setup Costs ◽

The Cost ◽

Single Batch

This study developed a model of batch scheduling involving the unavailability machine to minimize setup costs, cost of preventive maintenance and the cost of rework in a stable machine. This model is considered necessary in order to understand the effect of the unavailability machine for production runs and to understand the effect on the batch production schedule. The results of this study indicate that the first and last run will not give single batch. Given a hypothetical example of how the model and algorithm developed solve the problem instance.

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Optimal control policy for a Brownian inventory system with concave ordering cost

Journal of Applied Probability ◽

10.1239/jap/1450802743 ◽

2015 ◽

Vol 52 (4) ◽

pp. 909-925 ◽

Cited By ~ 8

Author(s):

Dacheng Yao ◽

Xiuli Chao ◽

Jingchen Wu

Keyword(s):

Optimal Control ◽

Brownian Motion ◽

Cost Optimization ◽

Control Policy ◽

Optimization Criterion ◽

Inventory System ◽

Single Pair ◽

Normal Density ◽

Strong Condition ◽

Demand Distribution

In this paper we consider an inventory system with increasing concave ordering cost and average cost optimization criterion. The demand process is modeled as a Brownian motion. Porteus (1971) studied a discrete-time version of this problem and under the strong condition that the demand distribution belongs to the class of densities that are finite convolutions of uniform and/or exponential densities (note that normal density does not belong to this class), an optimal control policy is a generalized (s, S) policy consisting of a sequence of (si, Si). Using a lower bound approach, we show that an optimal control policy for the Brownian inventory model is determined by a single pair (s, S).

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Design Criteria for Hardturning Machines

10.1115/imece1999-0739 ◽

1999 ◽

Author(s):

Shouri Yasui ◽

Kazutoshi Sakai

Keyword(s):

Energy Consumption ◽

Tool Material ◽

Low Energy ◽

Design Criteria ◽

Setup Costs ◽

Machine Technology ◽

Rolling Contacts ◽

Low Energy Consumption ◽

Increasing Demand

Abstract The benefits of hardturning include reduced setup costs; shorter tool change times; improved squareness by virtue of the ability to machine cylinder I.D., O.D. and face in one chucking; low energy consumption and elimination of the need to handle grinding sludge and waste fluid. Hardturning has typically been used as a replacement for grinding, in the processing of fitting surfaces or clad surfaces, and other such relatively straightforward applications not requiring sliding. In recent years, however, due to advances in servo and other machine technology, and tool material improvements (CBN, ceramics), hardturning has entered the realm of finishing curved and complex shaped surfaces that have sliding and rolling contacts. This paper will present the machine characteristics developed to meet the ever increasing demand for hardturning process accuracy, and introduce each of the factors which ultimately affected the design of machine components, providing examples where appropriate.

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