• Journal of the Society of Disaster Information
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• v.8 no.3
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• pp.242-257
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• 2012

Korea's population change trend is the aging and feminization as Reduction in mortality, average life extension. and is further increased Reduction of birth rate and aging population. if Our country concluded FTA(Free Trade Agreement) with the United States, Europe and China etc. labor-intensive industries will be the decline. Then, the construction workers' jobs are continually reduced. This is critical to the nation's economic, social and environmental influences due to Shortage of construction workforce and increasing labor costs. Eventually this is a major factor in reduced construction productivity. Therefore, this study is presented as a construction productivity development prospects on the value-added analysis per Labour productivity employee from Construction market trends, industry-specific productivity index, industry trends Employed, age tiered workforce trends, women's workforce trends, labor time trend, foreign workers, workforce trends, analysis of trends in construction contract, awarded by Company Size trends, construction management analysis index.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.137-153
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• 2019

Estimating tunnel construction time and costs are the most fundamental part of a tunnel project planning, which has been generally assessed on a deterministic basis until now. In this paper, excavation cycle time was investigated for two road tunnels and one subway tunnel, and the results were compared with the Standard of Construction Estimate (SE), which is made for the estimation of construction time and cost in a design stage. The results show that the difference in cycle time between SE and actual cycle time is 50%, 7% and 31% respectively for the three tunnels, which means that SE does not reflect practical operation time. The major reasons of the difference are skilled level of tunneling workers, the change of operation sequences for more effective operations, much more complicated working atmosphere in a tunnel than the assumption of SE etc. Finally, even though the results can not be generalized since investigated tunnels are only 3, but it is thought that SE needs to be upgraded into the model able to consider quite common situations through additional tunnel investigation and studies in the future.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.161-163
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• 2012

Recently on Value Engineering(VE) and Life Cycle Cost(LCC) social interests is increasing. The government Turn Key, BTL projects and public works projects, such as VE and LCC Analysis on the value and economic analysis is mandatory. And accordingly the VE and LCC analysis is underway for the various studies. However, there is a problem existing in the LCC analysis. Worth the cost varies according to the flow of time. However, the real interest rate during the LCC analysis of buildings in calculation time for interest rates and inflation are not considering the value of the flow. In other words, a few years using the average value of the deterministic analysis method has been adopted. These costs for the definitive analysis of the cost of an uncertain future, unforeseen changes resulting hazardous value. In this study of the last 15 years interest rates and inflation targeting by using Monte-Carlo Simulation is to perform probabilistic analysis. This potential to overcome uncertainties of the cost of building a more scientific and LCC Estimation of the probability value of the real interest rate is presented.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.4
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• pp.80-89
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• 2000

In this paper, we propose a new CPLD technology mapping algorithm for sequential circuit under time constraints. The algorithm detects feedbacks of sequential circuit, separate each feedback variables into immediate input variable, and represent combinational part into DAG. Also, among the nodes of the DAG, the nodes that the number of outdegree is more than or equal to 2 is not separated, but replicated from the DAG, and reconstructed to fanout-free-tree. To use this construction method is for reason that area is less consumed than the TEMPLA algorithm to implement circuits, and process time is improved rather than TMCPLD within given time constraint. Using time constraint and delay of device the number of partitionable multi-level is defined, the number of OR terms that the initial costs of each nodes is set to and total costs that the$^1$costs is set to after merging nodes is calculated, and the nodes that the number of OR terms of CLBs that construct CPLD is excessed is partitioned and is reconstructed as subgraphs. The nodes in the partitioned subgraphs is merged through collapsing, and the collapsed equations is performed by bin packing so that it fit to the number of OR terms in the CLBs of a given device. In the results of experiments to MCNC circuits for logic synthesis benchmark, we can shows that proposed technology mapping algorithm reduces the number of CLBs by 15.58% rather than the TEMPLA, and reduces process time rather than the TMCPLD.

• Korean Journal of Construction Engineering and Management
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• v.17 no.4
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• pp.95-102
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• 2016

Recently, a research regarding calculation of construction time extension-oriented incidental costs has been intensively suggested in quantitative aspect and recent studies on system improvement has been made continuously. In the case of Domestic Public Construction Works, State Contract Act is applied when the client is government whereas Local Government Contract Act is done when the client is local government, but more meticulous study is required because improvement plan is not proposed even there is a clear demand for improvement of these problems on calculation standard. Thus this study suggested appropriate standard by comparing each the calculation standards followed by 'State Contract Act' and 'Local Government Contract Act', considering the problems accorded, and analyzing field cases. Calculation method of other expenses was differently regulated as the revision of each regulation, and this demonstrates that there is a difference of actual cost from 12.37% to 24.95%. It is shown that less cost of construction time were calculated than actual cost according to a problem of calculation method by State Contract Act as the rate at the time of contract to be applied in other expense rate. This study suggested the rate against incidental cost and the rate of other expense per day against total construction cost as an appropriate rate calculation for other expense based on field database.

• Korean Journal of Construction Engineering and Management
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• v.12 no.3
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• pp.73-82
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• 2011

The term 'green' has become an important way of survival for the construction industry in 21th century in accordance with the emergence of the environmental crisis due to the climatic change. Especially the policy of carbon taxation, planed to be introduced from 2012, is expected to be a considerable burden to the construction industry which has abundant carbon emission during the resource transportation due to the complexity of resources and local distribution of the construction sites. In this regard, this study shows an optimizing strategy for delivery frequency, which downsizes the net distribution costs based on the assumption that, despite of its other advantagements, the frequent small lot mode of JIT delivery would take negative effects due to the increase of costs of transportation and carbon emission once the carbon taxation policy carried out. To simulate the efficiency of the management strategies, the System Dynamics modeling has been used. The results show that the frequent small lot transportation strategy is now always efficient method to these changes, and that the frequency of transportation should be re-determinated according to the extent of the imposition of carbon tax. This study provides the conceptual frame for an efficient management of transportation system of the construction industry, showing necessity of change of the resource transportation systems through analysing JIT deliver system in accordance with the global changes in environmental economy.

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.21-29
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• 2010

International construction contractors are often faced with the situation of working in an unfamiliar construction environment. Under FIDIC rules, the contractor has the right to make a claim requesting the consulting engineer for an adjustment to the contract price or the time for completion when a part or parts of the works have changed, or in the event of unforeseeable conditions. Contractors generally have more access to the costs and time implications of such a change or unforeseeable conditions than the consulting engineer or outside neutrals. Due to such an asymmetry of information, the contractor may be motivated to dispute frivolous claims of less merit, expecting erroneous judgments by the consulting engineer or the neutrals. In this paper, a claiming behavior model is presented by using game theory and experience data to study the manner in which frivolous claims develop into disputes. The model also analyzes the impacts of DAB/DRB upon the frivolous claims.

• KIEAE Journal
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• v.17 no.1
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• pp.5-13
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• 2017

Purpose: This study, by comprehensively the characteristics of new Hanok application techniques with the proposed site application technology in the course of the design changes that have been accumulated through Hanok technology development the second stage business, by analyzing the range of reflection, new Considering the direction reflects the efficiency of the new Hanok application techniques. Method: new Hanok application technology, it was been established through research and development of large 1 new Hanok technology it has been proposed through the "site-specific application techniques" and 2 builders and designers "space-time proposed technique" Analysis of the case, at the center of the design changes, the land the body of laws and regulations, the requirements of the public buildings, compared to the construction method and the like for the reduction of construction costs, new Hanok applied technology in the process of change by it There was analyzed whether acceleration on the range and step which is reflected in the design Result: The result of new Hanok applied technology was built through the demonstration build business case, process another major technology, foundation, woodwork, walls, roof, has been reflected in the ceiling construction, the inclusion of items in the proposed technique of construction , it was applied to the main steps in general, except for other construction work landscaping. Application techniques and construction proposal technology research team has presented, show the difference between the scope and method. With significance effort to improve the unreasonable traditional methods of these core processes that can be reflected in the field repeated the construction proposed technique as a result of the utility that can be applied for substantial construction.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.344-348
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• 2008

During the last few years, the use of Pre-tensioned spun High strength Concrete(PHC) pile has been gradually increased in many construction sites such as super high-rise and large building construction. there is almost no specific code and/or standard described in the specifications to check verticality for Pre-tensioned Spun High Strength Concrete pile installation process. The most commonly used method for the vortical PHC pile installation is a naked-eye measurement or water level measurement conducted by assistant crew in the construction sites. And recent analysis results of the pile cutting work revealed that it frequently makes a lot of cracks which significantly reduce the strength of the pile and is very labor intensive work, thus requiring a large amount of additional time, costs, and efforts. The main objective of the research is to analize problems and to improvement. measure of PHC Pile Construction. The improvement measure present to the main problem with survey and discussion.

• Journal of Intelligence and Information Systems
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• v.15 no.4
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• pp.213-224
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• 2009

This paper describes a real-time scheduling system re-construction project for automated manufacturing at a 300mm wafer fab of Korean semiconductor manufacturing company. During executing this project, for each main operation such as clean, diffusion, deposition, photolithography, and metallization, each adopted scheduling algorithm was developed, and then those were implemented in a real-time scheduling system. In this paper, we focus on the scheduling algorithms and real-time scheduling system for clean and diffusion operations, that is, a serial-process block with the constraint of limited queue time and batch processors. After this project was completed, the automated manufacturing utilizations of clean and diffusion operations became around 91% and 83% respectively, which were about 50% and 10% at the beginning of this project. The automated manufacturing system reduces direct operating costs, increased throughput on the equipments, and suggests continuous and uninterrupted processings.