• Journal of the Korean Society of Combustion
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• v.23 no.1
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• pp.21-27
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• 2018

The effect of swirl flow structures on combustion dynamics of two interacting, lean-premixed flames was experimentally investigated, with a particular emphasis on swirl numbers and swirl rotational directions. Our results show that the amplitude of limit cycle oscillations is very sensitive to the combination of swirl numbers and rotational directions, while the instability frequency remains nearly unchanged. The counter-rotating cases show significantly lower pressure perturbations, and this behavior appears to be related to the formation of compact interacting zone with higher heat release rate, indicating the presence of increased flame surface wrinkling caused by intense turbulence.

• Journal of Construction Engineering and Project Management
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• v.3 no.4
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• pp.5-11
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• 2013

Construction industry is overwhelmed by delay and often has suffered cost and time overrun. In this context, Last Planner System (LPS) has been considered as a very useful tool for the management of the construction process. Many previous studies have reported its effectiveness in construction performance. This study aims to evaluate the level of importance of the Last Planner processes in the Vietnam construction industry (VCI), and analyze the existing barriers when implementing these processes in construction management. These barriers were collected based on previous studies from International Group for Lean Construction (IGLC). A survey was carried out through questionnaire. The respondents are been experienced people in construction project management. There are four processes of LPS that were investigated including master schedule, phase schedule, lookahead plan, and weekly work plan. The results showed that master schedule is the most important item when performing a construction project in the VCI. The highest degree of agreement belongs to 'owner - contractor' pair with 77.1% importance indices; whereas the lowest belongs to 'consultants - contractors' pair with 63.8% importance indices. Eventually, three barrier factors were extracted from factor analysis technique with 62.2% of variance explained.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.278-281
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• 2008

As all industries field has changed very quickly, the field of construction faces in many changed. It is the representatively change that focus on the growth of quality level than increase of the quantity in construction. Whether the project successes or not is related to the survival of the company and it is necessity that we need performance measurement indicators to complete the project successfully. The domestic construction company considers overbearingly the cost-performance indicator in executing a project so far. It is rare of studies that suggest the methodology of more deeply measurement and analysis about the each project itself. The performance measured methodology based on Lean Construction is linked with the each project performance measurement methodology. This methodology uses three indicators such as the reliability, effectiveness and productivity at the sane their measuring whether each task is completed at the point of work. The measurement on the three performance indicators measure and evaluate whether the task is completed on the focus of construction duration. The research suggest the work plan reliability and weight of the performance measurement methodology based on the Lean Construction and the three considerately in the scope of measurement. If the suggestion is considered fully, we can indicate more objective and accurate construction project performance measurement indicators based on Lena Construction.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.557-562
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• 2008

In Korean construction industry, a public sector's ordering volume has been constantly increased after 2000. But, because a cost, schedule and quality control generally depends on a result-centric management form and a transparent management is not done during the construction in the Korean public business, it is recognized that this causes problems including an increase of cost and schedule, incomplete construction, a difficulty to find the problem in advance to establish measures, and an unclear locus of responsibility of constructor, supervisor and designer. Accordingly, this study is intended to derive the problems and the limit of management by identifying and analyzing the management state of the present government construction client for the client organization of public sector's government construction. Also, the study is intended to contribute to the client's efficient and actual project management by presenting the model of supplementing or improving the derived problem and limits to the client's organization.

• Journal of Construction Engineering and Project Management
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• v.4 no.3
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• pp.1-12
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• 2014

Construction management has been suffering from many problems, which need to be solved or better understood. Most of construction projects have not achieved efficiency as expected. In this context, waste was also considered as a problem of efficiency decrease, and poor production planning was considered as a cause for waste. This study was conducted on the basis of waste concepts and production planning processes based on the philosophies of Lean Construction. A survey to find out the relationship between them was carried out through questionnaire, which was answered by experienced people in construction projects. The results have shown that frequency of wastes occurrence is quite high, and production planning processes are superficially performed in construction phase. There is a significant negative relationship between production planning and waste occurrence (r = -0.262). Weekly Work Plan (WWP) is the most dominant plan for waste control with seventeen in total of nineteen waste factors, and phase plan is the most dominant plan for two remaining waste factors. A case study was adopted to validate the relationship between production planning and waste occurrence. The results showed that the better the project was planned, the fewer the waste would occur on construction sites.

• Architectural research
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• v.20 no.4
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• pp.147-152
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• 2018

As construction projects become larger, process plans become more complex, and inadequate process management leads to waste of time and resources. Effective process management requires process management techniques that can identify problems inherent in the process, continuously improve, and reflect interdependent process characteristics. In the field, the day's details by work type and work status are to be entered in the work daily report. However, even when important information is written, it is not directly linked to the overall process management. This study aims to propose specific process management and decision-making plan based on actual worker by visualizing and quantifying the information described in the existing work daily report. It is expected efficient process management to increase reliability and productivity through process management, which can increase the utilization of work daily reports and facilitates organic communication among participants.

• Korean Journal of Construction Engineering and Management
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• v.5 no.4 s.20
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• pp.71-78
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• 2004

In this study, the concept of Just-In-Time, Lean Construction and Supply Chain Management have been applied to furniture works of high-rise residental building. For the purpose of systematic furniture work planning, it should be established to analyse furniture-work process from design phase through contract, and procurement to construction phase. The analysis of process and data for furniture-work provides the roles of conducting subjects and presents management items at each phase. This proposal will provide the systematic furniture-work managements and reduce construction time and cost, and also raise the quality of furniture works.

• Journal of Construction Engineering and Project Management
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• v.6 no.1
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• pp.11-19
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• 2016

Most of the Indian contractors are not well equipped to handle the growing demand of infrastructure development; hence construction projects frequently run in to time and cost overruns, disputes and quality issues. This study aims to improve the construction industry in India by implementing lean principles to eliminate non-value adding activities (wastes). The purpose of this study is to 1) identify the wastes and their sources affecting the construction process, and 2) to identify problems and document lessons by applying a Last Planner System (LPS) to a sample project. First, the researchers identified that Delays, Rework, and Interruptions were the most critical wastes affecting the construction process and Poor management control, Poor Planning and Shortage of Resources were the major sources of the above mentioned wastes. Second, the researchers report the Percent of Planned Complete (PPC) analysis results and experienced problems after implementation of LPS at the sample project. It was observed that much more improvement could have been achieved if there was consensus between the owners and the contractor on the implementation of the LPS in its entirety. Some of the problems experienced in the implementation of the LPS like lack of scheduling, resource and material shortage were found to be similar to those in developed countries.

• Journal of the Korea Institute of Building Construction
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• v.11 no.4
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• pp.396-406
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• 2011

Execution of the finish work for high-rise residential construction occurs when a mixture of work progresses simultaneously at each floor or sector and is carried on by highly-specialized subcontractor teams. Therefore, the finish work plan requires an effective scheduling method that interfaces between the work and the teams. In order to address these issues, the TACT technique is utilized in Korea. This technique is based on Line-of-Balance and Lean construction. However, according to recent case studies, finish work using TACT technique was frequently delayed with cost overruns because the work was performed without a detailed schedule control plan outlining the relationship between architecture and mechanical, electrical, and plumbing work. This paper describes the enhanced-TACT technique which provides a detailed work flow chart and TACT work template. With improved TACT technique, this paper will contribute to improved cash flow and reduced cycle time and provide quality improvement through work continuity.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.25-33
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• 2004

The waste concrete produced by the process of the highway construction and management, has been crushed in-situ, and the waste aggregate has been experimentally used for anti-freezing layer and lean concrete. After testing the bearing capacity on anti-freezing layer, it was found that when the waste aggregates mixed with natural sand would be within the required gradations, the layer meets the requirements of limitation and the percentage to passing 2$\sim$20mm sieve increased by 5$\sim$13% because the flimsy mortars on aggregate were re-crushed by vibrated-roller compactor. The compressive strength of lean concrete using recycled aggregate was 71$\sim$85% of the natural coarce aggregate made, but nevertheless the recycled aggregates are applicable to the lean concrete because they largely exceeded the required strength, $57.5kgf/cm^2$.