• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.44-51
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• 2017

In today's competitive environment, supply chain management is a major concern for a company. Two of the key issues in supply chain management are transportation and inventory management. To achieve significant savings, companies should integrate these two issues instead of treating them separately. In this paper we develop a framework for modeling stochastic programming in a supply chain that is subject to demand uncertainty. With reasonable assumptions, two stochastic programming models are presented, respectively, including a single-period and a multi-period situations. Our assumptions allow us to capture the stochastic nature of the problem and translate it into a deterministic model. And then, based on the genetic algorithm and stochastic simulation, a solution method is developed to solve the model. Finally, the computational results are provided to demonstrate the effectiveness of our model and algorithm.

• International Journal of Quality Innovation
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• v.2 no.2
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• pp.136-144
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• 2001

The Markov Chain approach is used to develop an economic adjustment model of a process whose quality can be affected by a single special cause, resulting in changes of the process mean by incorrect adjustment of the process when it is operating according to its capability. The $\bar{X}$ control chart is thus used to signal the special cause. It is demonstrated that the expressions for the expected cycle time and the expected cycle cost are easier to obtain by the proposed approach than by adopting that in Collani, Saniga and Weigang (1994). Furthermore, this approach would be easily extended to derive the expected cycle cost and the expected cycle time for the case of multiple special causes or multiple control charts. A numerical example illustrates the proposed method and its application.

• Advances in Traditional Medicine
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• v.4 no.2
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• pp.95-99
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• 2004

The ethanolic extract of some medicinal plants having anti-asthmatic activity such as Solanum xanthocarpum, Curcuma longa, Glycyrrhiza glabra, Piper longum, A. vasica, A. lebbeck, and Tinospora cordifolia was evaluated for antihistaminic and anti-cataleptic activity. The aqueous solution of ethanolic extract of S. xanthocarpum and G. glabra potentiated histamine-induced tracheal chain contractions. Whereas, C. longa, P. longum, and T. cordifolia, and A. lebbeck were without any significant effect on histamine. Only A. vasica inhibited histamine-induced tracheal chain contraction. G. glabra per se produced contraction of the tracheal chain, which was blocked by pretreatment with atropine. Single dose of S. xanthocarpum potentiated clonidine-induced catalepsy but on repeated doses (once in a day for 3 days) inhibited catalepsy. Pretreatment with ethanolic extract of C. longa, P. longum, T. cordifolia inhibited catalepsy whereas G. glabra and A. lebbeck significantly potentiated clonidine-induced catalepsy. None of the extracts inhibited haloperidol-induced catalepsy. Thus the extracts having antihistaminic activity or mast cell stabilizing activity inhibited clonidineinduced catalepsy.

• IE interfaces
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• v.23 no.4
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• pp.327-336
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• 2010

We consider a supply chain consisting of a make-to-order manufacturer and N component suppliers and study the impacts of the number of suppliers on component inventory management. The manufacturer has full information and continuously observes the state of both component inventory level and customer backorders. Based on this information, the manufacturer determines whether or not to place a component purchasing order to a supplier among N suppliers even though some orders are in process by other suppliers. The goal of this paper is to numerically identify the manufacturer's purchasing policy which minimizes the total supply chain cost and the best choice of N. Our model contributes to the current literature in that the problem of simultaneously considering multiple outstanding orders and incorporating order setup cost into the model has not been covered yet. From numerical experiment, we investigate how much the policy with N suppliers can contribute to reducing the supply cost compared to the policy with a single supplier.

• Applied Microscopy
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• v.48 no.4
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• pp.126-127
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• 2018

Carbon has numerous allotropes and various crystalline forms with full dimensionalities such as diamond, graphite, fullerenes, and carbon nanotubes leading a wide range of applications. Since the emerge of graphene consisting of a single atomic layer of carbon atoms, a fabrication of all-carbon-based device with combination of one-, two-, and three-dimensional carbons has become a hot issue. Here, we introduce an ultimate one-dimensional carbon atomic chain. Carbon atomic chains were experimentally created by removing atoms from monolayer graphene sheet under electron beam inside transmission electron microscope (TEM). A series of TEM images demonstrate the dynamics of carbon atomic chains over time from the formation, transformation, and then breakage.

• IE interfaces
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• v.16 no.3
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• pp.280-290
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• 2003

Many firms are trying to optimize their production and distribution functions separately, but possible savings by this approach may be limited. Nowadays, it is more important to analyze these two functions simultaneously by trading off the costs associated with the whole. In this paper, I treat a production and distribution planning problem for single-period inventory products comprised of a single production facility and multiple customers, with the aim of optimally coordinating important and interrelated decisions of production sequencing and vehicle routing. Then, I propose a hybrid genetic algorithm incorporating several local optimization techniques, HGAP, for integrated production-distribution planning. Computational results on test problems show that HGAP is effective and generates substantial cost savings over Hurter and Buer's decoupled planning approach in which vehicle routing is first developed and a production sequence is consequently derived. Especially, HGAP performs better on the problems where customers are dispersed with multi-item demand than on the problems where customers are divided into several zones based on single-item demand.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.4
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• pp.139-151
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• 2009

Based on single-vendor single-buyer integrated production-inventory problem, a model considering freight costs discounts is suggested when the cargo capacity is constrained. With the cost function formulated, several properties of the model are derived and analyzed. An efficient algorithm to find solutions such as shipment lot size, number of shipments and number of full truckloads using properties derived is suggested. Numerical results are provided to illustrate the proposed solution procedures and to provide additional insights.

• Journal of the Korean Chemical Society
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• v.49 no.6
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• pp.537-545
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• 2005

• IE interfaces
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• v.13 no.3
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• pp.378-387
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• 2000

As the globalization of manufacturing companies continues, the scope of dependence between these companies and distributors, and other suppliers are growing very rapidly since no one company manufactures or distributes the whole product by themselves. And, the need to increase the efficiency of the whole supply chain is increasing. This paper deals with a multi-plant lot-sizing problem(MPLSP) which happens in a decentralized manufacturing system of a supply chain. In this study, we assume that the whole supply chain is driven by a single source of independent demand and many levels of dependent demands among manufacturing systems in the supply chain. We consider setup cost, transportation cost and time, and inventory holding cost as a decision factor in the MPLSP. The MPLSP is decomposed into two sub-problems: a planning problem of the whole supply chain and a lot-sizing problem of each manufacturing system. The supply chain planning problem becomes a pure linear programming problem and a Generalized Goal Decomposition method is used to solve the problem. Its result is used as a goal of the lot-sizing problem. The lot-sizing problem is solved using the CPLEX package, and then the coefficients of the planning problem are updated reflecting the lot-sizing solution. This procedure is repeated until termination criteria are met. The whole solution process is similar to Lagrangian relaxation method in the sense that the solutions are approaching the optimum in a recursive manner. Through experiments, the proposed closed-loop hierarchical planning and traditional hierarchical planning are compared to optimal solution, and it is shown that the proposed method is a very viable alternative for solving production planning problems of decentralized manufacturing systems and in other areas.

• The Journal of Information Technology
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• v.8 no.3
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• pp.143-158
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• 2005

The purpose of the paper is to analyze situations and its prospect of Single Window System for custom's one-stop service in Japan and to suggest effective application was to improve of in Korea's Customs systems. In response to the growing demand for lower trading costs and shorter and more predictable lead times with the advancement of the international trade supply chain, the Single Window System for import/export and port-related procedures was launched on 23 July 2003 in Japan. The concept of the Single Window System is to establish a comprehensive computer interface system that enables users to complete all import/export and port-related procedures required under different laws and regulations in a single input and single transmission. To realize the concept, the data elements and submission times of the various systems were harmonized, and manual procedures, such as quarantine and immigration, were computerized. Then, all the necessary systems, such as NACCS, Port EDI System, and Crew Landing Permit Support System, were interconnected as a Single Window System. Close cooperation among other governmental organizations and the private sector was a key factor in the successful development and smooth utilization of the System so that it fully met all parties' needs. It is anticipated that operating costs will be greatly reduced and trade facilitation will be enhanced as a result of the simplification of procedures. Korea Customs advocates the Single Window System as a best practice at ASEAN and WCO to contribute to the development of regional and international capacity building.