• Journal of the Korean Operations Research and Management Science Society
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• v.18 no.3
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• pp.151-157
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• 1993

In this paper, we investigate the effects of yield randomness for lot-sizing in a multi-stage production system. The practical importance of incorporating yield randomness into production models has been emphasized by many researchers. Yield randomness, especially in semiconductor manufacturing, poses a mojor challenge for production planning and control. The task becomes even more difficult if the demand for final product is uncertain. An attempt to meet the demand with a higher level of confidence forces one to release more input in the fabrication line. This leads to excessive work-in-process (WIP) inventories which cause jobs to spend unpredictably longer time waiting for the machines. The result is that it is more difficult to meet demand with exceptionally long cycle time and puts further pressure to increase the safety stocks. Due to this spiral effect, it is common to find that the capital tied in inventory is the msot significant factor undermining profitability. We propose a policy to determine the quantity to be processed at each stage of a multi-stage production system in which the yield at each stage may be random and may need rework.

• Journal of Distribution Science
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• v.17 no.11
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• pp.5-15
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• 2019

Purpose: This study aimed to empirically demonstrate how self-esteem, self-efficacy, locus of control, and neuroticism, which is core self-evaluation factors of door-to-door salespersons within food and cosmetic retail industry, affected the sales performance of female salespersons via job satisfaction and organizational commitment. Research design, data and methodology: Using a 23-item questionnaire constructed based on previous studies, this study selected six domestic door-to-door sales companies and conducted a 1:1 face-to-face survey with female door-to-door salespersons belonging to branches and agencies in Seoul and the capital region. The data of 208 respondents were analyzed. The results of path analysis based on structural equation modeling and mediation analysis through the Sobel test were presented. Results: Self-efficacy and locus of control had the largest effect on job satisfaction and organizational commitment, respectively. Neuroticism, however, did not significantly influence job satisfaction and organizational commitment. Overall, core self-evaluation factors positively affected sales performance via job satisfaction but not via organizational commitment. Conclusions: This study found that factors which were oriented to female salespersons' ability and sales goals, such as self-efficacy and job satisfaction, were considered important in managing them in the door-to-door sales-distribution channels. In the future, policies should be developed for managing female door-to-door salespersons to help them achieve job satisfaction.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.337-348
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• 2015

This research introduces the Financial Effect Measurement (FEM) models which measures both the improvement and the innovation performance of Quality Control Circle (QCC) and activities of Six Sigma. Concepts and principle of Comprehensive Income Statement (CIS), Balanced Scorecard (BSC), Time-Driven Activity Based-Costing (TDABC) and Total Productive Maintenance (TPM) are applied in order to develop the 4 FEM models presented in this paper. First of all, FEM using CIS depicts the improvement effects of production capacity and yield using relationships between demand and supply, and line balancing efficiency between bottleneck process and non-bottleneck processes. Secondly, cause-and-effect relation of Key Performance Indicator (KPI) is used to present Critical Success Factor (CSF) effects for QC Story 15 steps of QCC and DMAIC (Define, Measure, Analyze, Improve, and Control) of Six Sigma. The next is FEM model for service management innovation activities that uses TDABC to calculate the time-driven effect for improving the indirect activities according to the cost object. Lastly, FEM model for TPM activities presents the interpretation of improvement effect model of TPM Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) maintenance using profit, cash and Economic Added Value (EVA) as metrics of enterprise values. To better understand and further investigate FEMs, recent cases on National Quality Circle Contest are used to evaluate new financial effect measurement developed in this paper.

• The Research Journal of the Costume Culture
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• v.15 no.6
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• pp.1008-1022
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• 2007

The purpose of this study is to propose apparel sizing system for each body shape of early adolescent boys. The subjects of this study were 549 boys in the capital area. Their body shapes were classified and apparel sizing system was proposed for each body shape. For data analysis were performed descriptive statistics, correlation analysis and crosstabulation using SPSS Ver. 12. The control dimensions to propose apparel sizing system were stature and bust circumference for the upper garments. Intervals between sizes were 5cm for stature and irregular for bust circumference. For each type, $5{\sim}7$ sizes were proposed for upper garments. Reference measurements suggested for upper garments were 9 items. This study is meaningful in that it classified early adolescent boys' body shapes and proposed apparel sizing system for each type of body shape under the current circumstances where basic data for body shape classification and apparel sizing system of early adolescent boys were not in place.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.6
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• pp.563-568
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• 2013

The purpose of this study is to find the analytic solution for determining the optimal capacity (lot-size) of a batch-storage network to meet the finished product demand under infrequent shutdowns. Batch processes are bound to experience random but infrequent operating time losses. Two common remedies for these failures are duplicating another process or increasing the process and storage capacity, both of which are very costly in modern manufacturing systems. An optimization model minimizing the total cost composed of setup and inventory holding costs as well as the capital costs of constructing processes and storage units is pursued with the framework of a batch-storage network of which flows are susceptible to infrequent shutdowns. The superstructure of the plant consists of a network of serially and/or parallel interlinked batch processes and storage units. The processes transform a set of feedstock materials into another set of products with constant conversion factors.A novel production and inventory analysis method, the PSW (Periodic Square Wave) model, is applied. The advantage of the PSW model stems from the fact it provides a set of simple analytic solutions in spite of a realistic description of the material flow between processes and storage units. The resulting simple analytic solution can greatly enhance a proper and quick investment decision at the early plant design stagewhen confronted with diverse economic situations.

• Journal of the military operations research society of Korea
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• v.6 no.1
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• pp.93-101
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• 1980

An effectively designed budget system in the poor resources environment necessarily has three design criteria : (i) to be both planning-oriented and control-oriented, (ii) to be both rationalistic and realistic, (iii) to be sensitive to the variations of resources environment. PPB system is an extreme (planning-oriented and rationalistic) and conventional OEB/OUB system is the other extreme (control-oriented and incrementalistic). Generally, the merits of rationalism are limited because of the infeasibility of applications. Hence, mixtures of the two extremes such as MBO, ZBB, and RZBB have been examined and applied during the last decade. The classical mathematical models of capital budgeting are the starting points of the development of the Budget-Mix Model introduced in this paper. They are modified by the followings: (i) technological-resource constraints, (ii) bounded-variable constraint, (iii) the exchange rules. Special emphasis is laid on the above (iii), because we need more efficient interresource exchanges in the budget-mix process. The Budget-Mix Model is not based on optimization, but a heuristic approach which assures a satisficing solution. And the application fields of this model range between the incremental Nonzero-Base Budgeting and the rational Zero-Base Budgeting. In this thesis, the author suggests 'the budget- mix concept' and a budget-mix model. Budget-mix is a decision process of making program-mix and resource-mix together. For keeping this concept in the existing organization realistic, we need the development of quantitative models describing budget-mix situations.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.9
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• pp.854-862
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• 2012

The optimal design of batch-storage network by using periodic square wave model provides analytical lot sizing equations for a complex supply chain network characterized as multi-supplier, multi-product, multi-stage, non-serial, multi-customer, cyclic system including recycling and/or remanufacturing. The network structure includes multiple currency flows as well as material flows. The processes are represented by multiple feedstock/product materials with fixed composition which are very suitable for production processes. In this study, transportation processes that carry multiple materials with unknown composition are added and the time frame is changed from single period into multiple periods in order to represent nonperiodic parameter variations. The objective function of the optimization involves minimizing the opportunity costs of annualized capital investments and currency/material inventories minus the benefit to stockholders in the numeraire currency. The expressions for the Kuhn-Tucker conditions of the optimization problem are reduced to a multiperiod subproblem for average flow rates and analytical lot-sizing equations. The multiperiod lot sizing equations are different from single period ones. The effects of corporate income taxes, interest rates and exchange rates are incorporated.

• The Journal of Korean Academic Society of Nursing Education
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• v.10 no.1
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• pp.64-74
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• 2004

This study was conducted to investigate what contents nurses want in the intensive major course of junior nursing college. Data were collected for four months from October 2002 to February 2003 by structured questionnaires. Subjects were 240 registered nurses in working at five hospitals and four public health centers and elementary or middle schools in the capital and its suburbs and country. The collected data were analyzed using SPSS 8.0 program. The results of this study were summarized as follows : 1. Nurses working at hospitals want the programs which involve the contents as follows : emergency nursing/CPR, infection control, critical care, caner pt. care, pain control, hospice, pulmonary disease pt. care, analysis of lab. exam, heart disease pt. care, chronic disease pt. care, DM pt. care, digestive-system disease pt. care, nervous-system disease pt. care, elderly pt. care, immune-system disease pt. care, endocrine-system disease pt. care. 2. Nurses working at public health centers want the programs which involve the contents as follows : home nursing, family nursing, management of DM, HT, degenerative disease, and chronic liver disease, elderly pt. care, health education, maternity nursing, rehabilitation nursing. 3. Nurses working at elementary or middle schools want the programs which involve the contents as follows : prevention of drug abuse or misuse, sex education and consultation, health education, consultation technique, emergency care, prevention of child obesity, prevention and management of adult disease in children, teaching method, method of school health room management.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.278-292
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• 2008

The purpose of this study is to propose apparel sizing system for each body shape of early adolescent boys. The subjects of this study were 549 boys in the capital area. Their body shapes were classified based on 47 anthropometric measurements, 43 photographic measurements and 10 indexed measurements. The apparel sizing system was proposed for each body shape. For data analysis were performed descriptive statistics, correlation analysis and crosstabulation using SPSS Ver. 12. The control dimensions to propose apparel sizing system were stature and waist circumference for the lower garments. Intervals between sizes were 5cm for stature and irregular for waist circumference. For each type, $5{\sim}8$ sizes were proposed for lower garments. Reference measurements suggested fur lower garments were 7 items. This study is meaningful in that it proposed apparel sizing system for each type of body shape. The results of this study are expected to contribute to planning sizes according to the type of body shape and improving the fitness of ready-made clothes in apparel and school uniform manufacturers.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.8
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• pp.335-343
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• 2021

This paper investigates the effect of institutional quality on FDI inflows by using FDI outflows from Asian countries from 2009 to 2017. We used the FDI data from five major Asian economies, which are South Korea, China, Japan, Singapore, and Hong Kong. The gravity model was used to examine the effect of institutional quality on FDI flows. The regression model considers several independent variables, and we select the most appropriate variables by using the Bayesian Model Averaging (BMA) estimator. We have shown that foreign direct investment from Asian countries depends on the size of home and the partner countries, geographical distance, trade interaction between two countries, economic freedom, labor supply, tariff rate, and capacity of the government. The results of different estimation techniques emphasize that multinational enterprises prefer to invest in those countries which have a higher income, which shows the evidence for Lucas's paradox. The results also show that economic freedom and control of corruption have a positive impact on FDI inwards. The regression results show that better institutional quality in host countries encourages more FDIs from Asian economies. It suggests that the state should control corruption and create a free economic environment to attract FDIs.