• Journal of Korean Society of Industrial and Systems Engineering
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• 제43권3호
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• pp.10-20
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• 2020

This paper presents a method to measure the similarity of assigned jobs in the gravure printing operation based on the chromaticity and color sequence, and order the jobs accordingly. The proposed dispatching rule can be used to fulfill diverse manufacturing site requirements because the parameters can be adjusted to prioritize chromaticity and color sequence. In general, dispatching rules either ignore the job-changing time or require that the time be clearly defined. However, in the gravure printing operation targeted in this study, it is difficult to apply the general dispatching rule because of the difficulties in quantifying the job-changing time. Therefore, we propose a method for generalizing assignment rules of the job planner, allocating relative similarity among assigned jobs, and determining the sequence of jobs accordingly. Chromaticity priority is determined by the arrangement of the color assignments in the printing operation; color sequence priority is determined by the addition, deletion, or change in a specific color sequence. Finally, the job similarity is determined by the dot product of the chromaticity and color sequence priorities. Implementation of the proposed dispatching rule at an actual manufacturing site showed the planner present the same job order as that obtained using the proposed rule. Therefore, this rule is expected to be useful in industrial sites where clear quantification of the job-changing time is not possible.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• 제22권9호
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• pp.724-727
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• 2009

We have fabricated (Ba,Sr)TiO3$TiO_3$ thick films doped with various amount of ZnBO dopants (1, 3, and 5 wt%) by screen printing method on the alumina substrates, which were sintered at the temperature below $1200^{\circ}C$. With increasing the amount of ZnBO dopants, the relative dielectric permittivity of ZnBO doped (Ba,Sr)$TiO_3$ was decreased, while loss tangent was increased. 1 wt% ZnBO doped (Ba,Sr)$TiO_3$ thick film has relative dielectric permittivity of 759 at 1 MHz, while 3 and 5 wt% of ZnBO doped (Ba,Sr)$TiO_3$ thick films have 624 and 554, respectively. By introducing ZnBO dopants to the (Ba,Sr)$TiO_3$ thick films, leakage current densities were decreased. The decreased leakage current with increasing ZnBO dopants can be explained by increased density and grain size of thick film on alumina substrate. We believe this decreased leakage current density probably come from the increased grain size and increased density.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.647-651
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• 2007

The Lean Construction is adopted from Lean Principle of Manufacturing Industry in the early of 1990, that has been providing theoretical background and good practical implementation for maximizing customers' satisfaction and improving productivity through minimizing the waste factors in the construction operations. The Last Planner System(LPS), one of the elementary techniques of Lean Construction, aims for improving the work reliability and reducing variability by measuring and managing the daily or weekly performance for overcoming the weakness of recent complex schedule management tools such as Critical Path Method. This research is propose a framework for implementation of LPS conducted by owner in plant construction.

• Journal of the Korean Home Economics Association
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• 제39권6호
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• pp.61-78
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• 2001

The objectives of this study were to examine the propensity of job related variables, self-esteem, overall job satisfaction, satisfaction about six categories in the job(task, boss, payment, co-workers, promotion, job environment) of life insurance planners, to investigate the effects of self-esteem, demographic variables, job characteristics variables on the overall job satisfaction and the satisfaction of six categories in the job. The survey of this study was conducted by means of self-administered questionnaire with 275 life insurance planners located in Taegu. Major findings were as follows:(1) The propensity of self-esteem and overall job satisfaction of life insurance planners averages 3.75 and 3.35 points(5 Likert scale). The propensity of satisfaction about task, boss, payment, co-workers, promotion, job environment of life insurance planners averages 4.22, 2.67, 1.68, 2.09, 1.71, 2.65 points separately(5 Likert scale). (2) According to the results for examining the relative influences of variables affecting overall satisfaction of life insurance planners, the relative importance of related variables are in the order of , self-esteem in the job, social dignity of the job, the prospect about the dignity of life insurance planner, the motive of having job. Explanatory power of these variables totaled 43.5%.

• Journal of the Korea Institute of Military Science and Technology
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• 제15권4호
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• pp.424-434
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• 2012

This paper presents a path planning algorithm of the unmanned aerial vehicle for the neutralization of the enemy firepower. The long range firepower of the ememy is usually located at the rear side of the mountain which is difficult to bomb. The path planner not only consider the differential constraints of the Unmanned Aerial Vehicle (UAV) but also consider the final approaching angle constraint. This problem is easily solved by incorporating the analytical upper bounded continuous curvature path smoothing algorithm into the Rapidly Exploring Random Tree (RRT) planner. The proposed algorithm can build a feasible path satisfying the kinematic constraints of the UAV on the fly. In addition, the curvatures of the path are continuous over the whole path. Simulation results show that the proposed algorithm can generate a feasible path of the UAV for the bombing mission regardless of the posture of the tunnel.

• Journal of Ocean Engineering and Technology
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• 제36권1호
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• pp.41-49
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• 2022

With the advancement of intelligent vehicles and unmanned systems, there is a growing interest in underwater surveys using autonomous marine vehicles (AMVs). This study presents an automated planning strategy for a long-term survey mission using a fleet of AMVs consisting of autonomous surface vehicles and autonomous underwater vehicles. Due to the complex nature of the mission, the actions of the vehicle must be of high-level abstraction, which means that the actions indicate not only motion of the vehicle but also symbols and semantics, such as those corresponding to deploy, charge, and survey. For automated planning, the planning domain definition language (PDDL) was employed to construct a mission planner for realizing a powerful and flexible planning system. Despite being able to handle abstract actions, such high-level planners have difficulty in efficiently optimizing numerical objectives such as obtaining the shortest route given multiple destinations. To alleviate this issue, a widely known technique in operations research was additionally employed, which limited the solution space so that the high-level planner could devise efficient plans. For a comprehensive evaluation of the proposed method, various PDDL-based planners with different parameter settings were implemented, and their performances were compared through simulation. The simulation result shows that the proposed method outperformed the baseline solutions by yielding plans that completed the missions more quickly, thereby demonstrating the efficacy of the proposed methodology.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 한국건설관리학회 2003년도 학술대회지
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• pp.113-119
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• 2003

Since Lean Construction has been introduced as a new management approach to improve productivity in the construction industry, much research is in progress to develop lean concepts and principles for better implementation and to get results of the successful adaptation of lean ideas from manufacturing for application in the construction industry. Currently, several construction companies in the USA have applied the Last Planner System (LPS), a decentralized system developed by the Lean Construction Institute. Thus, there are demands to share information how other companies implement lean construction, to identify the benefits and barriers of lean implementation in the construction fields, and finally to improve their lean implementation. This study carried out case studies to assess current lean construction projects with the objective to find out how effectively and to what extent lean construction is being adapted by the construction industry. This study will only introduce the Last Planner which has four levels in the LPDS, findings based on interviews with project participants, and observations from the projects. This study will also provide empirically identified success factors associated with lean implementation on the construction site. Finally, the recommendations are offered to support the effort of adaptation of lean construction in the domestic construction industry. Even though lean construction still stood on the bridge crossing from current practice to lean practice, it is the researcher's conviction that lean construction would be successfully adapted to the construction industry in the near future and would be recognized as an effective management innovation.

• Journal of Navigation and Port Research
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• 제33권10호
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• pp.723-734
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• 2009

Container Vessel is becoming larger and faster thanks to the rapid growth of global trade and development of technology. Therefore, 15,000TEU vessel is expected to be ordered in near future. Every nations in north-east Asia are facing strong competition to be logistics hub to get the initiatives of logistics in response to the rapid change of logistics environment. According to the globalization of economy and major ports in this region also are trying to catch big shipping line for their survival. Considering above circumstances of the advent of ultra-large container vessel and spoke-and-hub strategy, it is inevitably necessary to make a fast and accurate vessel job in the terminal in order to be a leading port To meet this objective, current vessel planning system has to be improved innovatively. Therefore, this thesis propose multi distributed vessel planning system which enables multi loading/discharging planning with several planner simultaneously for faster and more accurate than existing planning and enhances quality of planning through information sharing among planners. Also this thesis uses simulation through Arena to verify the efficiency of this multi-distributed vessel planning system.

• Journal of Construction Engineering and Project Management
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• 제5권2호
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• pp.11-15
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• 2015

The Last PlannerSystem (LPS) has been implemented on construction projects to increase work flow reliability, a precondition for project performance againstproductivity and progress targets. The LPS encompasses four tiers of planning processes:master scheduling, phase scheduling, lookahead planning, and commitment / weeklywork planning. This research highlights deficiencies in the current implementation of LPS including poor lookahead planning which results in poor linkage between weeklywork plans and the master schedule. This poor linkage undetermines the ability of theweekly work planning process to select for execution tasks that are critical to projectsuccess. As a result, percent plan complete (PPC) becomes a weak indicator of project progress. The purpose of this research is to improve lookahead planning (the bridgebetween weekly work planning and master scheduling), improve PPC, and improve theselection of tasks that are critical to project success by increasing the link betweenShould, Can, Will, and Did (components of the LPS), thereby rendering PPC a betterindicator of project progress. The research employs the case study research method to describe deficiencies inthe current implementation of the LPS and suggest guidelines for a better application ofLPS in general and lookahead planning in particular. It then introduces an analyticalsimulation model to analyze the lookahead planning process. This is done by examining the impact on PPC of increasing two lookahead planning performance metrics: tasksanticipated (TA) and tasks made ready (TMR). Finally, the research investigates theimportance of the lookahead planning functions: identification and removal ofconstraints, task breakdown, and operations design.The research findings confirm the positive impact of improving lookaheadplanning (i.e., TA and TMR) on PPC. It also recognizes the need to perform lookaheadplanning differently for three types of work involving different levels of uncertainty:stable work, medium uncertainty work, and highly emergent work.The research confirms the LPS rules for practice and specifically the need to planin greater detail as time gets closer to performing the work. It highlights the role of LPSas a production system that incorporates deliberate planning (predetermined andoptimized) and situated planning (flexible and adaptive). Finally, the research presents recommendations for production planningimprovements in three areas: process related, (suggesting guidelines for practice),technical, (highlighting issues with current software programs and advocating theinclusion of collaborative planning capability), and organizational improvements(suggesting transitional steps when applying the LPS).

• Proceedings of the Korea Association of Information Systems Conference
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• 한국정보시스템학회 1997년도 추계학술대회논문집 기업경쟁력 향상을 위한 정보통신 기술의 활용
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• pp.39-52
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• 1997

본 연구는 언어 교육용 프로그램을 개발하는 저작도구9authoring tool)와 학생들이 자율적으로 학습할 수 있는 지능형 컴퓨터 교사시스템(ITS : Intelligent Tutoring System)으 로 구성된 지능형 학습환경(Intelligent Learning Environment)을 설계한다. 특히, 범용시스 템에서 제공되는 불필요한 기능들을 제거하고 언어교육에 필요한 기능만을 가진 간편한 저 작도구의 설계와, 인공지능 기법을 이요하여 학생 개개인의 지식수준에 따라 차별화하여 지 능적으로 교육할 수 있는 지능형 교사시스템의 구성 방법을 제안한다.