• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.5
• /
• pp.3477-3483
• /
• 2015

A reasonable process for the activity duration estimation is required for the successful construction management because it directly affects the entire construction duration and budget. However, the activity duration is being generally estimated by the experience of the construction manager. This study suggests an estimation model of construction activity duration using neural network theory. This model estimates the activity duration by considering both the quantitative and qualitative elements, and the model is verified by a case study. Because the suggested model estimates the activity duration by a reasonable schedule plan, it is expected to reduce the error between planning duration and actual duration in a construction project.

• Journal of the Korea Society of Computer and Information
• /
• v.25 no.12
• /
• pp.1-15
• /
• 2020

In this paper, we propose a novel method for converting the existing 2D processes in the design and construction phase of civil engineering, to the future BIM-based processes. First, we compare and analyze the actual application processes of the outputs of the existing 2D method and the outputs of the 3D BIM method, for the whole process of BIM design of earthworks and road structures and integrated utilization of quantity, process(4D) and construction cost(5D), in view of life-cycle. The proposed method acquire the outputs of the design phase integrating IFC international common standard file information and CBS/OBS/WBS standard classification scheme information, and acquire the outputs of the construction stage by using an integrated utilization module for quantity, process(4D) and construction cost(5D). Ultimately, we intend to commercialize the step by step technologies for BIM design and construction in civil engineering by using the proposed method.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.176-183
• /
• 2008

Recently, several large-scale Mega-Projects are being conducted. For these urban revitalization projects which requires many complex functions, the existing project management system based on single project level is limited in application. Therefore, our main objectives of this research are two 1) Develop a brand-new program management system(Prototype Ver 1.0) for mega-projects where various facilities are combined both horizontally and vertically. 2) Develop management strategies(Prototype Ver 1.0) based on the program level that enable the comprehensive management of a multiple various projects. The subtitles of this Research are i-PMIS(Program Management Information System) Development, Standardization & Optimization of Construction Life-Cycle Process, Comprehensive Project Cost & Process Management Technology, Effective and Optimized Integrated Performance Management Technology, and, we suggest to optimize the whole life cycle process, predict and respond to various risks, predict and control the process, the cost and the schedule, achieve maximum return on investment to the participating parties, and provide a brand-new Program-MIS including the visual-based web-portal platform to respond the changing business environments and decision making.

• Korean Journal of Construction Engineering and Management
• /
• v.3 no.4 s.12
• /
• pp.93-103
• /
• 2002

The reinforcement concrete work is the work affected by structural safety, durability, and schedule with form work. The domestic reinforcement concrete works have mainly worked the process of re-barfabrication/assembly on site. Finally it have low productivity. Then this paper analyzed waste factors and the process of re-bar fabrication/assembly on site for the productivity improvement and value-added productivity improvement. Waste factor analysis aims at maximizing value-added by the value analysis of re-bar fabrication and assembly on site. Finally, Value-AddingActivity(VAA)ismuchlessthan non-value adding activity. Especially, Non-Value-Adding Activity(NVAA) generates waste such as the activity steps, labors, equipments, materials, time, and soon. And it was non-flow production, over production, and analyzed into having to shift value. This paper aimsat maximizing value-addingactivity and minimizingnon value-addingactivity through waste factor analysis in process for the improvement of value added productivity.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2004.11a
• /
• pp.462-467
• /
• 2004

Design-build, which is defined as single source responsibility for design and construction, has been widely used in large public works since governmental formulation of measure for encouraging use of design-build in 1996. However, civic groups and small and medium sized enterprises are highlighting over-competition and unbalanced market shares of conglomerate in domestic design-bid market and insisting on decrease in the use of design-build and absorption into the lowest-price bidding. This study collected information about cost, schedule, quality, new technology adoption from 51 civil design-build projects and measured their performance.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2004.11a
• /
• pp.210-215
• /
• 2004

In can occur to many problems on progressing step without close scope definition, interrelation definition between activities, resource plan, and schedule plan on planning step. But it have not closely defined performance system on planning step because of many constraints of domestic construction industry. Therefore this paper intends to discuss a method of calculating optimal cost and duration using Linear Programming that solves maximing or minimizing problems among decision making methodology and Monte Carlo Simulation that decreases to probability errors. With outcoms applying Linear programming and Monte Carlo Simulation for calculating optimal cost and duration, follow as : With outcomes applying Monte Carlo Simulation, it could calculate reliable estimator about project duration through removing various constraints. With outcomes applying Linear programming, it could calculate optimal value about project cost through defining various variables and constraints on many activities.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.5
• /
• pp.144-152
• /
• 2012

The reason why most scheduling softwares currently using at construction projects adopt PDM (Precedence Diagramming Method) is that it can express an overlapping relationship between activities. However, the overlapping relationships in PDM are represented only by combinations of four overlapping types that connect the start and finish points of two activities, therefore, PDM cannot express efficiently the relationships between any middle points of two activities if they should be represented. This research proposes the method of transforming the four overlapping types of PDM to the overlapping relationships of BDM(Beeline Diagramming Method), new networking technique, that can connect the inter-relationships at any middle points of two activities as well as express multiple overlapping relationships. The proposed method will help not only to improve an efficiency of scheduling but also to upgrade the scheduling technique because BDM technique has a lot of unique advantages in scheduling.

• Korean Journal of Construction Engineering and Management
• /
• v.5 no.5 s.21
• /
• pp.135-142
• /
• 2004

This paper proposes the CPM bar chart (CBC), a hybrid of the bar chart and the critical pad method (CPM). The CBC overcomes shortages of the fenced bar chart, while still keeping advantages. The fence with direction is applied instead of the broken fence, which triggers considerable problems to identify and apply in the fenced bar chart. In addition, the notorious task to find dummy activities is no longer required. Upon the benefits of simplicity in the bar chart and logical work sequence in the CPM network. the CBC provides a relatively easy way to create and understand a schedule, thus improving communication quality between project participants. With the advantages, the CBC can also be effectively applied to various scheduling techniques such as resource constrained scheduling, resource leveling, scheduling with activity split, delay impact analysis, etc.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.8
• /
• pp.1451-1459
• /
• 2011

Recently, low energy houses have become an essential issue globally and various subsidy programs are ongoing to penetrate. All-electric houses which are another type of low energy houses or zero carbon houses are being developed. These houses consider new & renewable energy and demand side management programs in the construction and the diffusion process because these programs are essential policies to use energy resources reasonably. This paper shows a simulation methodology to control home appliances in all-electric houses considering the electricity consumption pattern of residents. The simulation is a first step to estimate energy saving of the house in a practical manner.

• Water for future
• /
• v.35 no.5
• /
• pp.51-59
• /
• 2002

In recent years the human impact on the environment becomes increasing lift threatening, calls for the better management of resources. In field of water quality of river flow, the best way to conserve water quality is specific efforts to control the pollutant loadings and treat the loadings in the basin to reduce the discharge of pollutant loadings to river. But in general the water quality influenced by the dam discharge. Especially in dry season, it is more dominant way to improve the water quality which contaminated with the pollutant loadings from the basin. The dam discharge amounts of the 2 dams in the Keum River that maintain the down stream water quality were estimated for the year of 1999, 2001, 2006, 2011, in case of irrigation and non-irrigation seasons. The pollutant loadings for the basin are estimated with the planning of treatment plants construction schedule for every sub-basins. The river flow rates were considered low flow as 2.33 year low flow and 10 year low flow. The QUAL2E model was used as a tool of simulation.