• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.31-39
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• 2010

As the linear scheduling method has been used since the Empire State Building linear schedule in 1929, it is being applied in various fields, such as construction and manufacturing. When addressing concurrent critical paths occurring in a linear construction schedule, empirical researches have stressed resource management, which should be applied for optimizing workflow, ensuring flexible work productivity and continuous resource allocation. However, work relationships have been usually overlooked in making the linear schedule from an existing network schedule. Therefore, this research analyzes the previous researches related to the linear scheduling model, and then proposes a method that can be applied for adopting the relationships of a network schedule to the linear schedule. To this end, this research considers the work relationships occurring in changing a network schedule into a linear schedule, and then confirms the activities movement phenomenon of linear schedule due to workspace change, such as physical floors change. As a result, this research can be used as a basic research in order to develop a system generating a linear schedule from a network schedule.

• Journal of Korea Water Resources Association
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• v.43 no.12
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• pp.1039-1050
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• 2010

Relative accuracy of six discharge measurement methods-velocity-area method, rod-float method, ADCP moving-vessel method, ADCP fixed-vessel method, electromagnetic wave surface velocimeter (EWSV), LSPIV- is evaluated by comparing discharges measured by them with dam released discharges. Data from 39 times of concurrent discharge measurement campaigns are analyzed. Except the rod-float method, measured discharges show absolute errors less than 6.2% with dam discharges. When the four methods is evaluated by being compared with discharges measured with the conventional velocity-area method, discharges with electromagnetic wave surface velocimetry shows 7.35% of absolute errors and other three methods shows absolute errors less than 6%. The rod-float method, which shows large discrepancy compared with dam and velocity-area method, need complementary verification.

• Korean Journal of Construction Engineering and Management
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• v.12 no.5
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• pp.35-45
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• 2011

Establishing housing supply strategies in Korean housing market is a crucial issue due to contradictory but concurrent two problems in market; one is the unstable working-class residential and the other is the high vacancy rate by the low-level of sales rate. Although government has been continuously implementing various supply policies in an attempt to evenly distribute houses as well as to keep supply and demand in balance, it is difficult to satisfy all of stakeholders, such as housing consumers, housing owners and housing suppliers. This paper, therefore, applies a system dynamics methodology and offers a dynamic and integrated model encompassing for-profit behaviors of each market participants. The proposed model simulates the future trends of house prices, the balances between supply and demand, construction companies earnings and vacancy rate when applying various housing supply scenarios. From the simulation result, recent governmental small-size rental housing supplies in bulks should utilize private construction companies to stabilize housing distribution rate and private supply system as well as the supply and demand are well balanced.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.111-118
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• 2015

This research aims to utilize lapilli from the Mt. Baekdusan as environmently-friendly construction material. First of all, the neutralizing method for fabricating lapilli-cement-mixed bioblock was examined. And then, by use of the neuralized bioblock with microorganism for water purification, the growth inhibition effect against the pathogenic coliform bacillus was evaluated. The result regarding growth inhibition effect on pathogenic coliform bacillus indicates that the pretreatment condition, which is a concurrent procession with aqueous solution of 10% di-ammonium Phosphate after water curing, led to pH degraded below 10 which was the target value. Therefore it was concluded that the method was effective on bio-block neutralization. The microorganisms purifying water and di-ammonium phosphate were detected through the examination for microorganism existence on the bioblock, therefore it was concluded that the bioblock composed of lapilli and cement is able to be utilized in various structures as an environment friendly construction material.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.11
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• pp.1228-1237
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• 1992

Network management represents those activities which control and moitor the use of resources. Remote delegation model supports flexible and effective distribution of management functions among managers and agents, and it may cause an reliable network management in a relatively complex and high-speed networks. in this model, managers delegate to agents execution of management programs as prescribed in a management scripting language. In addition, primitives included in the management programs enable agents to monitor and control localmanaged objects effectively. We suggest management algorithms in which management scripts are delegated from managers to agents and partiality implement OSI fault management. This mans gement algorithm can effectively support delegation and control concurrent accesses to management information. Moreover, it can be easily translated into object-based concurrent programming language: ABCL. In this paper, we will scrutinize some essential aspects of this management.

• Journal of KIBIM
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• v.7 no.3
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• pp.40-48
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• 2017

It only takes one failed project to wipe out an entire year's profit, when the projects are not managed efficiently. Additionally, escalating costs of materials and a competitive local construction market make subcontractors a challenge. Subcontractors have finite resources that should be allocated simultaneously across many projects in a dynamic manner. Significant scheduling problems are posed by concurrent multi-projects with limited resources. The objective of this thesis is to identify the effect of productivity changes on the total cost resulting from shifting crews across projects using a descriptive model. To effectively achieve the objective, this study has developed a descriptive cost model for a subcontractor with multi-resources and multi-projects. The model was designed for a subcontractor to use as a decision-making tool for resources allocation and scheduling. The model identified several factors affecting productivity. Moreover, when the model was tested using hypothetical data, it produced some effective combinations of resource allocation with associated total costs. Furthermore, a subcontractor minimizes total costs by balancing overtime costs, tardiness penalties, and incentive bonus, while satisfying available processing time constraints.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.191-194
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• 2005

Over the past decade, changes in product development processes and increased consumer demands have dramatically influenced engineering working practices and targets. The information technology revolution has made its appearance concurrent to this relentless escalation in product engineering requirement. It has offered hopes for improved productivity despite these increasing demands. The wide availability of personal computing power, virtually inexhaustible sources of information and an abundance of computerized engineering tools have created great expectations. Knowledge information modeling system and database were developed using ASP and Microsoft SQL 2000 Server to share the DB that can be utilized to process on the web.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.223-225
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• 2006

A ball moving on a beam is a typical nonlnear dynamic system, which is often adopted to proof test diverse control schemes. Ball and plate system is the extension of the traditional ball and beam problem that moves a metal ball on a rigid plate. In this paper, a trajectory planning and tracking problem is proposed for ball and plate system, which is to control the ball from a point to another without hitting the obstacles. Our scheme is composed of three controllers, TS type optimal path tracking controller, mandani type obstacle avoidance controller and trajectory planning controller that determines the desired trajectory. But this type of construction can give rise to chattering executions. Because the difference of contributions from concurrent controllers can cause behaviors unsmoothly. We propose fuzzy pid supervision control1er to handle this problem.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.05a
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• pp.253-260
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• 2001

해양 플랜트분야는 다양한 제품의 생산을 위해 여러종류의 CAD 모델, 도면, 기술 자료를 주고 받으면서 생산을 위한 정보를 생성하게 된다. 이를 위해 컴퓨터내에서 쉽고 빠르게 제품을 모델링할 수 있는 기술, 이 기종 CAD간의 데이터 변화기술이 필요하며 엔지니어링 전문회사, Owner, Maker 용역회사, 플랜트 주설계팀간의 제품정보 교환을 위하 PDM 기술이 요구된다. 또한, 해양플랜트 생산과 관련된 제품정보를 체계적으로 관리하기 위해서 테이터베이스를 기반으로 하는 PDM(Plant Data Management) 기능을 적용하여 업무 Process 별로 변화하는 제품정보들의 체계적 분류기법을 제시하고 동시공학(Concurrent Engineering)환경을 설명하고자 한다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.47
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• pp.289-302
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• 1998

Concurrent Engineering(CE) can provide a competitive edge for companies that have confronted with rapidly changing market requirements, such as shortening of product life cycles, high quality, low cost, diversity of customer demand, and so on. We construct a prototype of integrated information system to support a new product development process by CE concept. This integrated information system can be useful for considering concurrently all of the aspect in the product design process. In this system, an Engineering Database is constructed for gathering data of four departments; i.e. marketing, production, quality control and design department. Also DFM(Design For Manufacturability) is applied for analysis of product design.