• Journal of Korean Society for Quality Management
• /
• v.31 no.4
• /
• pp.95-116
• /
• 2003

The primary purpose of this paper is to determine the impact of shared values, conflicts and balanced power that reside in the relationships between airline maintenance engineers and pilots who are considered to be core components in operating aircraft. According to the analysis, the higher the shared values, the lower the conflicts, and the more balanced power between those two parties, the higher the mutual trust and job satisfaction levels. It was also found that the quality of flight operation changes depending on the mutual trust and job satisfaction levels. These results clearly show that the quality of flight operation is directly related to the interactions among two parties and feelings for each other in an environment where mutual dependencies are highly required.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.19 no.3
• /
• pp.139-149
• /
• 1994

In many project-oriented production systems, e. g., shipyards or large-scale steel products manufacturing, resource loading by an activity is flexible, and the activity duration is a function of resource allocation. For example, if one doubles the size of the crew assigned to perform an activity, it may be feasible to complete the activity in half the duration. Such flexibility has been modeled by Weglarz [13] and by Leachman, Dincerler, and Kim [7[ in extended formulations of the resource-constrained poject scheduling problem. This paper presents a new algorithmic approach to the problem that combines the ideas proposed by the aforementioned authors. The method we propose involves a two-step approach : (1) solve the resource-constrained scheduling problem using a heuristic, and (2) using this schedule as an initial feasible solution, find improved resource allocations by solving a linear programming model. We provide computational results indicating the superiority of this approach to previous methodology for the resource-constrained scheduling problem. Extensions to the model to admit overlap relationship of the activities also are presented.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1994.04a
• /
• pp.410-420
• /
• 1994

In many project-oriented production systems, e.g., shipyards or large-scale steel products manufacturing, resource loading by an activity is flexible, and the activity duration is a function of resource allocation. For example, if one doubles the size of the crew assigned to perform an activity, it may be feasible to complete the activity in half the duration. Such flexibility has been modeled by Weglarz [131 and by Leachman, Dincerler, and Kim [7] in extended formulations of the resource-constrained project scheduling problem. This paper presents a new algorithmic approach to the problem that combines the ideas proposed by the aforementioned authors. The method we propose involves a two-step approach: (1) solve the resource-constrained scheduling problem using a heuristic, and (2) using this schedule as an initial feasible solution, find improved resource allocations by solving a linear programming model. We provide computational results indicating the superiority of this approach to previous methodology for the resource-constrained scheduling problem. Extensions to the model to admit overlap relationships of the activities also are presented.

• Journal of the Korean Institute of Navigation
• /
• v.17 no.4
• /
• pp.73-87
• /
• 1993

As a result of accepting the '71 FUND Convention and enforcing the Oil Pollution Compensation Act 1992, we observed some benefits and costa. This paper analyses those benefits and costs and suggests se-veral key policy recommendations for the estasblishment of an effective oil pollution compensation regime in Korea. This paper identifies the said benefits and costs as follows : First, by establishing the oil pollu-tion compensation system as same as the international level, most of small and medium size of oil pollution damage which are caused by coastal tankers will be compensated by FUND. Second, most of oil pollution damage which are not covered by '69 CLC will be compensated by FUND. Third, some parts of FUND Contribution Fee and CRISTAL Contribution Fee to be charged by major oil companies will be doubled. However the limit of international oil pollution compensation system and the loophole outside the Oil Pol-lution Compensation Act 1992 suggest followings : 1) Radical risk management and insurance manage-ment of ocean going tanker owners, 2) Establishment of oil pollution claim settlement system, 3) Enforce-ment of crew and ship management for coastal tanker and 4) Establishment of Korean P & I Club.

• Journal of Construction Engineering and Project Management
• /
• v.5 no.1
• /
• pp.40-46
• /
• 2015

This study presents the results of our analysis and recommendations for process and productivity improvements. The project studied consists of a 5-story research building, with a structure of steel frames supporting concrete slabs. The observations focused on the analysis of the overall erection and framing process. The methods used for the analysis consisted in intensive visits on site, where construction processes were observed in term of resources, activities, durations, materials' handling procedures, and technology used. Back to the office, authors used the information captured to model the different trades' activities, using work sampling and 5-minute rating technique. The work sampling provides insight into the activity, hence allowing for process improvements. The productivity of various trades is strongly dependent on the organization of the work process and work site conditions. Improving the productivity of the entire project or company is not possible until everyone is committed to improvement.

• Proceedings of the Safety Management and Science Conference
• /
• 2003.05a
• /
• pp.53-61
• /
• 2003

The process of railway traffic planning is composed of several steps such as long - term, mid - term, short - term, and real - time plan. The planning of vehicle and manpower resources is a main research topic in tactical short - term planning step Railway vehicle is usually consisted of a power car, passenger/freight cars and human resource is composed of engine driver, cabin crew, ground personnel. So far , power car was main research target in railway vehicle scheduling problem. Recently according as the light electric railway or high - speed railway is introduced, the operational planning of train set vehicles become important . In this paper , we introduce the conceptional model for trainset restoring problem and developed heuristic algorithm.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.31 no.2
• /
• pp.116-121
• /
• 2023

항공 사고는 첨단 항공 기술의 발달로 꾸준히 감소해 왔지만, 여전히 발생하고 있다. 조종사는 목적지 공항까지 안전하고 효율적으로 비행하기 위해 위협과 오류를 관리해야 한다. 조종사에게 영향을 미치는 위협은 환경적 위협과 항공사 위협으로 나눌 수 있으며, 환경사위협에는 객실 위협이 포함된다. 조종사와 객실 승무원은 정상적인 운항 중에는 협력이 필요하며, 비상시에는 안전한 비행을 위해 효과적인 협력이 절대적으로 필요하다. 조종사가 비행 중에 간섭이나 작업 흐름의 중단이 발생할 때 에러를 할 가능성이 높아진다. 항공사들은 안전 운항을 방해할 수 있는 객실위협의 종류를 적극적으로 식별하고 분석하여, 조종사들이 안전한 비행을 유지하기 위해서 위협을 관리하도록 절차 및 훈련을 개선해야 한다. 본 연구는 안전관리시스템(SMS)의 안전도구인 LOSA(Line Operation Safety Audit)를 기반으로 기내위협의 유형을 파악하고, 항공사들에게 조종실위협 관리를 체계적으로 개선하는 데 필요한 객실위협과 간섭에 대한 자료를 제공하고자 한다.

• International conference on construction engineering and project management
• /
• 2015.10a
• /
• pp.600-601
• /
• 2015

Both the importance and process of estimating Nuclear-power plant construction time and cost have increased in significance as energy user costs themselves have become more significant. In estimating construction time, few parameters are more significant than work item production rates and factors significantly affecting the rates. A standardized data collection tool was used to acquire a total of 401 data points from a S Nuclear-power plant project, for selected critical works: form-work, rebar-work, and concrete-pouring. With the data, several hypothesized drivers of the man-hour production rates and crew-day production rates were also analyzed. Findings from this study will enable industry professionals to enhance accuracy of time and cost estimation for nuclear power plant construction.

• Journal of Construction Engineering and Project Management
• /
• v.4 no.2
• /
• pp.31-40
• /
• 2014

The management of vehicular supply of "perishable" construction material, such as concrete mixes, faces a series of uncertainties such as weather, daily traffic patterns and accidents. Presented in this paper is a logistics control model for managing a hauling fleet with interrelated processes at both ends and queue capacities. Discrete event simulation is used to model the complex interactions of production units and the randomness of the real world. Two alternative strategies for ready mix concrete delivery, with and without an off-site waiting queue, are studied to compare supply performance. Secondly, the paper discusses the effect of an agent-based GPS tracking system providing real-time travel data that lessens the uncertainty of trucking time. The results show that the combination of GPS information with off-site queuing reduces productivity loss and process wastes of concrete placement as well as the idleness of supply trucks when crew or pump experience an unexpected stoppage.

• Journal of Navigation and Port Research
• /
• v.39 no.1
• /
• pp.37-43
• /
• 2015

At marine construction sites, there are problems with regard to dispute on the responsibility of safety management of chartered barge and its legal issues. In general, demise charter with crew is used for barge charterparty which is committed to the marine construction. Although Chapter 5 of the Korean Commercial Act enact provisions regulating a Time Chargerparty and a Bareboat Charterparty, it is difficult to clarify where the responsibility lies with regard to the safety control of the chartered barge. For this reason, disputes on accountability arise when accident occurs in effect. As a result, parties of the charterparty shift the responsibility on each other and there is increased risk for occurrence of similar accidents. There is no legally required qualification for a head of barge workers who is in charge of barge management. It is not possible to demand the head of barge workers to take charge of tasks which requires professional judgment as a marine technician considering his daily work scope. Furthermore, the barge committed to the marine construction as a form of bareboat charter or equipment charterage is an object which should be managed by safety supervisor of the charterer's marine construction. The charterer bears a duty to manage the safety of the barge. Therefore, the charterer is generally liable for the damage incurred in the course of using the chartered barge.