• Industrial Engineering and Management Systems
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• v.12 no.3
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• pp.172-180
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• 2013

We herein consider a stochastic multi-item inventory management problem in which a warehouse sells multiple items with stochastic demand and periodic replenishment from a supplier. Inventory management requires the timing and amounts of orders to be determined. For inventory replenishment, trucks of finite capacity are available. Most inventory management models consider either a single item or assume that multiple items are ordered independently, and whether there is sufficient space in trucks. The order cost is commonly calculated based on the number of carriers and the usage fees of carriers. In this situation, we can reduce future shipments by supplementing items to an order, even if the item is not scheduled to be ordered. On the other hand, we can reduce the average number of items in storage by reducing the order volume and at the risk of running out of stock. The primary variables of interest in the present research are the average number of items in storage, the stock-out volume, and the number of carriers used. We formulate this problem as a multi-objective optimization problem. In a numerical experiment based on actual shipment data, we consider the item shipping characteristics and simulate the warehouse replenishing items coordinately. The results of the simulation indicate that applying a conventional ordering policy individually will not provide effective inventory management.

• Women's Health Nursing
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• v.12 no.4
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• pp.316-325
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• 2006

Purpose: The purpose of this study was to develop a Critical Pathway for Uterine Artery Embolization patients. Method: There were 6 steps that were taken. Step 1 was selecting a diagnosis, and Step 2 was organizing a development team consisting of 7 experts. Step 3 analyzed the medical records, and Step 4 drew up a preliminary Critical Pathway. Step 5 tested the clinical validity of the preliminary Critical Pathway, and Step 6 developed the final Critical Pathway. Result: The contents of the medical practices observed in the medical records were investigated in seven areas: monitoring/assessment, treatment, medication, diet, activity, consults, and education/discharge plan; and a total of 73 items was identified. The validity of the 73 items was examined by a group of specialists. 68 items were adopted, 4 items revised, 1 item removed, and 1 item was added. Using the results, a preliminary Critical Pathway was drawn up. According to the results from examining the clinical validity of the preliminary Critical Pathway with five patients for five weeks, 3 items which showed discrepancy were revised and another 3 items were added. Then, the final Critical Pathway was completed. Conclusion: This Critical Pathway needs to be clinically applied and continuously to measure its effects in terms of the length of stay, cost.effectiveness, and the patients' and staffs' satisfaction.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.23-26
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• 2004

Recently, most of countries in the world are investing huge amount of capital for the infrastructure of logistics and trying to gain dominating position in logistics. To play the role of important hub in logistics, an efficient, flexible, and fault-tolerant transportation process should be developed. Minimization of transportation cost and timely deliveries in the unpredictable environment are a few of the important issues in logistics. This study suggests a way of transporting goods to destinations at the minimal cost and with the minimal delay by optimally allocating transporting resources. Various attributes in transportation such as due date, priority etc. are also considered. Appropriate transporting resources for each work item is selected by calculating the weighted sum of the cost factor and the delay factor assuming that initial sequences of work items are given. A policy to reallocate transporting resources is also suggested when work items or transporting resources are added or deleted because of accidents or disturbances. This policy provides adaptability to the allocation methodology which enables the system to cope with changing environment by controlling various attributes in transportation. Genetic algorithm is used for this approach.

• Journal of Korean Institute of Industrial Engineers
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• v.1 no.2
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• pp.27-38
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• 1975

This paper explores a quantitative decision-making system for planning production, inventories and work-force in a multi-item production system. The Multi-item Parametric Decision Rule (MPDR) model, which assumes the existence of two types of linear feed-back rules, one for work-force level and one for production rates, is basically an extension of the existing method of Parametric Production Planning (PPP) proposed by C.H. Jones. The MPDR model, however, explicitly considers the effect of manufacturing progress and other factors such as employee turn-over, difference in work-days between month etc., and it also provides decision rules for production rates of individual items. First, the cost relations of the production system are estimated in terms of mathematical functions, and then decision rules for work-force level and production rates of individual items are establised based upon the estimated objective cost function. Finally, a direct search technique is used to find a set of parameters which minimizes the total cost of the objective function over a specified planning horizon, given estimates of future demands and initial values of inventories and work-force level. As a case problem, a hypothetical decision rule is developed for a particular firm (truck assembly factory).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.202-203
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• 2020

Unlike price calculation by cost accounting, which categorizes costs into material costs, labor costs, and miscellaneous expenses to determine the construction budget price, construction cost calculation based on Construction Standard Unit Prices utilizes unit prices extracted from market prices of items from projects already completed to estimate costs of similar construction projects. Although unit price information is collected through construction site surveys to revise these construction standard unit prices every year, but due to the limitations of the site survey method, it is difficult to quickly implement the rapid changes in the construction methods and market prices. As such, an important issue that arose was the identification of work items whose prices need urgent revision. This study conducted research on factors that need to be considered when developing online survey system for monitoring construction site market prices. This study is expected to enhance convenience for users, and provide an efficient data collection and management system for administrators.

• Journal of applied mathematics & informatics
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• v.6 no.2
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• pp.539-552
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• 1999

An order-level inventory model for a perishable product with a time-dependent demand is developed for a fixed planning pe-riod allowing backlogging in all cycles within the said period. The market demand is assumed to decrease exponentially as time elapses. The average system cost is derived and its optimization procedure is illustrated with a numerical example. Sensitivity of the optimal so-lution to changes in the values of different parameters of the system is also analysed.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.4
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• pp.115-123
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• 1993

This paper presents an alternative inspection method for counting items of a lot(or kit) in production lines or distribution centers. In this inspection, lots are weighed instead of counting all items of the lots in order to reduce the effort required for the 100% manual counting inspection. Inspection errors of this inspection procedure are analyzed and the impact of the variability of item weights on inspection errors are investigated. Two approaches, the cost assessment approach and the bicriterion decision making approach, are presented for the implementation of this inspection procedure.

• Journal of Korean Society for Quality Management
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• v.21 no.1
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• pp.65-77
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• 1993

Often in a production process, the quality of items is serially dependent. We assume that the quality of items is an attribute which can be classified as good or bad with a Markovian dependence structure. In order to determine sampling inspection plan characteristics such as total inspection cost and average outgoing quality, we design an economic model and illustrate an efficient procedure for design of best inspection plan using graphs based on numerical calculations.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1497-1502
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• 2009

The present study has been conducted economic analysis of heat storage type ground source heat pump system(HSGSHP) and normal ground source heat pump (GSHP) and central boiler system with individual air conditioning facility which are installed at the same building in the shared an apartment house. Cost items, such as initial construction cost, annual energy cost and maintenance cost of each system are considered to analyze life cycle cost (LCC) and simple payback period (SPP) with initial cost different are compared. The initial cost is a rule to the Government basic unit cost of production. LCC applied present value method is used to assess economical profit of both of them. Variables used to LCC analysis are prices escalation rate and interest rate mean values of during latest 10 years. The LCC result shows that HSGSHP (1,351,000,000won) is more profitable than central boiler system with individual air conditioning facility by 86.7% initial cost. And SPP appeared 8.0 year overcome the different initial cost by different annual energy cost.

• Journal of the military operations research society of Korea
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• v.28 no.2
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• pp.85-94
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• 2002

Calculation of proper expenses on acquisition and purchasing defense product is matter of survival and weighing the morality for both defense industry and the national facilities. With this reason, both parties have been a big job to estimate the resonable cost. The cost are composed of many subordinated parts such as material cost, labor cost, and so on. In the compositions of that cost, the most important part in between companies and the government throughout the whole calculating process is to define the proper labor cost. When both parties calculate imported articles or overhead expenses, they can easily calculate and confirm by documented evidences or related materials. In other hand, the labor cost, which can be seen as two absolutely different numbers and opinions can be created, depends on analyzer's point of view. These interpretation and judgment of data cannot avoid analyzer's intention. In accordance with the above matters, defining the reasonable labor cost will be the top priority in order to analyze the proper expenses. This study will provide a method of proper labor cost estimation before starting the actual manufacturing to calculate the rational labor cost.