• 한국직업건강간호학회지
• /
• 제9권2호
• /
• pp.110-120
• /
• 2000

The purpose of this study was to examine which factors affected the job stress of workers in the manufacturing industry. The subjects were 128 workers in automobile component manufacturing companies located in Kyonggi-do province. Data were collected through self-reporting technique for 8 days, October 24-31, 2000. The instrument to test the work related truss was NIOSH's Work-related Stress Inventory revised by Korea Occupational Safety and Health Association(KOSHA) in 1999. The collected data were analysed with SAS. and frequency, percentage, mean value, standard deviation, t-test, ANOVA. Scheffe's post hoc test and Pearson's Correlation Coefficients. The major findings were as follows: 1. Mean job stress score for the job-related stress was $2.6{\pm}0.5$ on the basis of 5.0 points. Job stress was significantly different according to gender. The stress by role conflict showed higher score than the stress by role ambiguity. 2. Discretionary power(freedom to determine) of workers was scored $2.6{\pm}0.7$ on the basis of 5.0 points. And it was significantly different according to gender, duration of work and shift experience. 3. The work environment scored $2.2{\pm}0.3$ on the basis of 3.0 points and significant difference according to gender, age, marital status, type of employment, type of service, and shift work. 4. Role ambiguity showed significant negatively correlate with job control(r=-.32, P=.000) and decision making(r=-.31, P=.000). And decision making showed positively correlated with job control(r=.62, P=.000), and role conflict(r=.26, P=.003).

• 산업경영시스템학회지
• /
• 제39권2호
• /
• pp.19-27
• /
• 2016

Maritime transport is now regarded as one of the main contributors to global climate change by virtue of its $CO_2$ emissions. Meanwhile, slow steaming, i.e., slower ship speed, has become a common practice in the maritime industry so as to lower $CO_2$ emissions and reduce bunker fuel consumption. The practice raised various operational decision issues in terms of shipping companies: how much ship speed is, how much to bunker the fuel, and at which port to bunker. In this context, this study addresses an operation problem in a shipping companies, which is the problem of determining the ship speed, bunkering ports, and bunkering amount at the ports over a given ship route to minimize the bunker fuel and ship time costs as well as the carbon tax which is a regulatory measure aiming at reducing $CO_2$ emissions. The ship time cost is included in the problem because slow steaming increases transit times, which implies increased in-transit inventory costs in terms of shippers. We formulate the problem as a nonlinear lot-sizing model and suggest a Lagrangian heuristic to solve the problem. The performance of the heuristic algorithm is evaluated using the data obtained from reliable sources. Although the problem is an operational problem, the heuristic algorithm is used to address various strategic issues facing shipping companies, including the effects of bunker prices, carbon taxes, and ship time costs on the ship speed, bunkering amount and number of bunkering ports. For this, we conduct sensitivity analyses of these factors and finally discuss study findings.

• 환경영향평가
• /
• 제8권3호
• /
• pp.61-76
• /
• 1999

For the effective management of urban forest, a variety of informations on urban forest needs to be accurately measured and effectively used in decision-making processes. This study aims at developing an urban forest management system with reference to GIS and making it possible to effectively manage urban forests. A detailed forest type map were constructed with the help of aerial photograph and terrestrial inventory. A geographical map in terms of slope, aspect and altitude were also prepared by Digital Elevation Model(DEM). A soil type map containing chemical characteristics were also made through soil analysis. These thematic maps which contain informations on forest type, geography and soil were digitalized with reference to GIS, and an urban forest management system of user interface were developed. With the help of this urban forest management system, various spatial and attribute informations which need for urban forest management could be easily used in decision-making processes in relation to urban forest.

• 한국건설관리학회논문집
• /
• 제14권3호
• /
• pp.22-32
• /
• 2013

일반적인 사회기반시설물 자산관리 절차는 기존 자산의 명확한 정보획득, 서비스수준의 설정, 요구수준의 분석, 재정상태와 가용예산의 분석, 자산관리 계획의 준비, 수정된 자산의 정보 획득 순으로 구성될 수 있다. 본 연구에서는 실제적인 위험도분석 기반의 개선된 교량 자산관리를 위하여 필요한 상태평가 및 성능측정, 성능척도의 설정, 파손형태 및 위험도 분석 등에 대한 방법론을 제시하였다. 보다 효율적인 교량 관리를 위하여 위험도 고려가 필요한 교량 기본현황정보 및 성능척도 항목을 설정하였고, 정량적 정성적 위험도를 고려한 성능평가방법을 제안하였다. 위험정도와 발생가능성을 고려한 위험도 매트릭스를 이용한 성능평가방법은 교량의 서비스수준을 보다 합리적으로 추정할 수 있다. 제안된 위험도분석 절차와 방법이 접목된 교량 서비스수준 평가방법을 이용하면 보다 합리적인 자산관리 의사결정이 가능하며, 향후 최적의 유지관리 의사결정을 위한 자산관리 체계구축 및 시스템 개발에 기여할 수 있을 것으로 판단된다.

• 한국산학기술학회논문지
• /
• 제16권2호
• /
• pp.1006-1015
• /
• 2015

본 연구에서는 공급사슬 네트워크에서 네트워크 기반 기업 간 기술의 적용과 그 확산에 영향을 주는 요인을 도출하고 요인들 간의 관계를 밝히고자 한다. 공급사슬관리의 효율성과 전체 최적화의 달성을 위해 도입된 기업 간 기술은 공급사슬 내 기업들의 적극적인 기술 도입과 공급사슬 네트워크상 빠른 확산이 필요하다. 하지만, 각 기업들마다 내 외부적인 요인들에 의해 도입시점이 각기 다르며 이로 인해 그 기술의 확산속도가 결정되어 진다. 특히, 공급사슬 상에 다수의 공급업체들이 존재하는 경우, 새로운 기술의 도입을 고려중인 잠재적 대상은 기업 내부적 요인뿐만 아니라 다른 기업들과의 관계요인에 의해 결정되어지는데, 관계 요인에 의한 영향은 그 기업과의 물리적 또는 사회적 접근성에 의해 결정된다. 본 연구는 미국 유통산업 내 소비재제품제조업체(CPG)들에게 도입된 기업 간 네트워크 기술 중의 하나인 재고추적기술의 도입과 확산에 대한 실증적 분석을 통해, 잠재적 사용자의 기술 도입 결정이 초기에는 몇몇 기업들의 내부적 요인의 영향에 의해 확산이 되다가 점차적으로 사회적 접근성과 같은 관계요인에 의해 영향을 받으며 공급사슬 전체적으로 기술 확산이 일어나는 것을 확인하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제16권4호
• /
• pp.225-237
• /
• 2016

In conventional transportation problem (TP), all the parameters are always certain. But, many of the real life situations in industry or organization, the parameters (supply, demand and cost) of the TP are not precise which are imprecise in nature in different factors like the market condition, variations in rates of diesel, traffic jams, weather in hilly areas, capacity of men and machine, long power cut, labourer's over time work, unexpected failures in machine, seasonal changes and many more. To counter these problems, depending on the nature of the parameters, the TP is classified into two categories namely type-2 and type-4 fuzzy transportation problems (FTPs) under uncertain environment and formulates the problem and utilizes the trapezoidal fuzzy number (TrFN) to solve the TP. The existing ranking procedure of Liou and Wang (1992) is used to transform the type-2 and type-4 FTPs into a crisp one so that the conventional method may be applied to solve the TP. Moreover, the solution procedure differs from TP to type-2 and type-4 FTPs in allocation step only. Therefore a simple and efficient method denoted by PSK (P. Senthil Kumar) method is proposed to obtain an optimal solution in terms of TrFNs. From this fuzzy solution, the decision maker (DM) can decide the level of acceptance for the transportation cost or profit. Thus, the major applications of fuzzy set theory are widely used in areas such as inventory control, communication network, aggregate planning, employment scheduling, and personnel assignment and so on.

• 동아시아식생활학회지
• /
• 제18권2호
• /
• pp.242-252
• /
• 2008

The objective of this study was to suggest a new efficiency measurement indicator for evaluating the menu management efficiency of decision making units(DMUs) in contract-foodservice operations and to determine the relationship between the DEA(data envelopment analysis) menu efficiency score and menu factors. The results of applying DEA revealed relatively efficient types of service and frequency of meals. The efficient service was shown as a self-service type that operates Monday to Saturday. The considered menu factors included meal price, food cost per meal, meal counts, number of menu items, use of favorite menu use, forecasting error, accuracy of ordering, ratio of inventory, ratio of food loss, use of processed foods and use of prepared vegetables are considered. There were significant correlations between the DEA score and meal price, meal counts, number of menu items, ratio of food loss, accuracy of ordering and use of processed foods respectively. According to the regression results, menu price had a positive influence on the DEA menu efficiency score, and food cost per meal and the use of prepared foods had negative influences respectively.

• 한국산학기술학회논문지
• /
• 제11권9호
• /
• pp.3304-3310
• /
• 2010

연구는 가격 및 수요 불확실성하의 강건한 (robust) 생산 및 수송 전략을 수립함으로써 수요 및 가격 불확실성이 존재하는 TFT-LCD 제조업 공급사슬망의 의사결정 문제를 해결하고자 한다. 품질로 구분되는 제품들의 생산, 재고 및 물류에 관한 의사결정을 조정하기 위해, 본 연구에서는 생산용량 제약, 해상/항공 수송 리드타임 및 용량 제약 등의 현실적인 제약조건들을 반영하는 확정적 모델을 정의하고, 시나리오 모델을 이용하여 수요 및 가격 불확실성을 함께 반영하는 확률적 혼합정수선형계획법모형들을 개발한다. 또한 개발된 확률적 모형들의 robust 솔루션을 도출하기 위한 휴리스틱 알고리즘을 제안한다. 그리고 이들 모형들로부터 산출된 솔루션의 성능을 실험을 통하여 다양한 시나리오 하에서 평가하도록 한다.

• 한국경영과학회:학술대회논문집
• /
• 한국경영과학회 1996년도 추계학술대회발표논문집; 고려대학교, 서울; 26 Oct. 1996
• /
• pp.139-145
• /
• 1996

소봉제품에 대한 시장생산 모형을 만들기 위하여 과거 자료에서 마련된 수량화된 기초 자료를 통계적으로 분석하고 미래의 생산량을 예측하였다. 출고량에 의한 기초 자료의 통계분석 결과에서 여러 가지 계량적 시계열 분석 방법들 중 STEPAR 방법에 의한 예측 방법이 가장 우수한 것으로 나타났다. 통계분석의 결과로 나타난 출고량에 대한 예측값은 생산량을 결정하는 데 있어서 매우 중요한 정보이다. 각 소봉제품들에 대해서 미래의 생산량에 대한 예측값을 STEPAR 방법에 의하여 얻었다. 이 예측값들의 95% 신뢰 구간의 폭이 상당히 넓게 나왔다. 이를 개선하기 위하여 체계적인 데이터 베이스 시스템을 구축하고, 수요-생산-재고의 종합적인 관리를 하며, 이를 뒷받침하기 위한 통합 전산 시스템을 구축해야 할것이다.

• 한국경영과학회지
• /
• 제30권3호
• /
• pp.17-39
• /
• 2005

The coordination of a three-level supply chain consisting of a supplier, a retailer, and a discount outlet (DCO) is studied here. We assume that the product is sold in two consecutive periods a Normal Sales Period (NSP) and a subsequent Clearance Salvage Period (CSP). A benchmark case is studied Initially in which the supply chain is coordinated by a s1n91e agent. Thus, the supplier the retailer, and the discount outlet design a common system that allows centralized decision making about stocking quantities, markdown time schedules, and policies on disposing of leftovers to deliver the greatest possible expected supply chain profit. Next, we consider a decentralized supply chain. Here, decisions are made without coordination. The objective is to maximize an individual party's expected profits. The focus of the study is on the following questions: what factors make the coordination an effective approach for the supply chain? How do we coordinate the supply chain so as to maximize the supply chain Joint expected profit? These and other related study issues are explored in this paper.