• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.10
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• pp.1794-1800
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• 2008

This paper presents a method of constructing the digital logic switching functions using PLA. First of all, we propose a MIN and MAX algebra arithmetic operation based on the Post algebra. And we discuss the T-gate which is used for realization of the MIN and MAX algebra arithmetic operation. Next, we discuss the MIN array and MAX array which are basic circuit of the PLA, also we discuss the literal property. For the purpose of the design for the digital logic switching functions using PLA, we Propose the variable partition, modular structure design, literal generator, decoder and invertor. The proposed method is the more compactable and extensibility.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.398-399
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• 2019

This paper presents a method of the circuit design of the multiple-valued digital logic switching functions based on the modular techniques. Fisr of all, we introduce the necessity, background and concepts of the modular design techniques for the digital logic systems. Next, we discuss the definitions that are used in this paper. For the purpose of the circuit design for the multiple-valued digital logic switching functions, we discuss the extraction of the partition functions. Also we describe the construction method of the building block, that is called the modules, based on each partition functions. And we apply the proposed method to the example, we compare the results with the results of the earlier methods. In result, we decrease the control functions, it means that we obtain the effective cost in the digital logic design for any other earlier methods. In the future research, we require the universal module that traet more partition functions and more compact module.

• Journal of Construction Engineering and Project Management
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• v.3 no.2
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• pp.21-34
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• 2013

Various risk factors affect construction projects. Due to the uncertainties created by risk factors, actual activity durations frequently deviate from the estimated durations in either favorable or adverse direction. For this reason, evaluation of schedule uncertainty is required to make decisions accurately when managing construction projects. In this regard, this paper presents a new computer simulation model - the Repetitive Schedule Risk Analysis Model (RSRAM) - to evaluate unit-based repetitive building project schedules under uncertainty when activity durations and risk factors are correlated. The proposed model utilizes Monte Carlo Simulation and a Critical Path Method based repetitive scheduling procedure. This new procedure concurrently provides the utilization of resources without interruption and the maintenance of network logic through successive units. Furthermore, it enables assigning variable production rates to the activities from one unit to another and any kind of relationship type with or without lag time. Details of the model are described and an example application is presented. The findings show that the model produces realistic results regarding the extent of uncertainty inherent in the schedule.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.233-240
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• 1999

Even though the recent construction safety disasters not only result in the loss inside construction sites but also become to a large public disasters, safety activities are managed in an irrational way and safety rules are ignored in the construction sites which leads to occur same type of disasters repeatedly. In this paper, a fuzzy set theoretic approach to risk analysis is proposed as an alternative to the techniques currently used in the general construction projects safety. Then the concept of risk evaluation using linguistic representation of the likelihood, exposure and consequences is introduced. A risk assessment model using approximate reasoning technique base on fuzzy logic is presented to drive fuzzy values of risk and numerical example for risk analysis is also presented to illustrate the results.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.353-354
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• 2023

Improving productivity in industries is a very critical issue, and improving labor productivity is especially important in construction industry, which is a labor-intensive industry. However, researches on labor productivity in construction industry are insufficient, and most of previous studies have limitations in terms of specificity and logic. In this study, fuzzy DEMATEL method was used to structural analyze of influence factors for labor productivity in construction industry based on previous researches and expert survey. The result of this study contributes to deriving priorities for improving labor productivity.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.556-560
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• 2011

Players of construction projects proceed with each work process by information gathering, modification and communication. Due to the complex and long-span lifecycle projects increased, it became more important to grasp this mechanism for the successful project performance in construction project. Hence, most project information management systems or knowledge management systems equip information retrieval system. There are two logic to infer the meaning of retrieval target; inductive reasoning and deductive reasoning. The former is based on metadata explaining the target and the later is based on relation between data. To infer the information flow, it is necessary to define the correlation between players and work processes. However, most established information retrieval systems are based on index search system and it is not focused on correlation between data but data itself. Thus, this research aims to research on process of information flow retrieval system for large-scale construction projects.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.195-200
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• 2021

In recent years, Vietnam's economic growth rate has been attributed to the growth of many well-managed industries within Southeast Asia. Among them is the civil construction industry. Construction projects typically take a long time to complete and require a huge budget. Many socio-economic variables and factors affect total construction project costs due to market fluctuations. In recent years, crucial socioeconomic development indicators of construction reached a fairly high growth rate. Also, most infrastructure and construction projects have a high degree of complexity and uncertainty. This makes it challenging to predict the accurate project price. These challenges raise the need to recognize significant factors that influence the construction price index of civil buildings in Vietnam, both micro and macro. Therefore, this paper presents critical factors that affect the construction price index using the fuzzy extent analysis process in an uncertain environment. This proposed quantitative model is expected to reflect the uncertainty in the process of evaluating and ranking the influencing factors of the construction price index in Vietnam. The research results would also allow project stakeholders to be more informed of the factors affecting the construction price index in the context of Vietnam's civil construction industry. They also enable construction contractors to estimate project costs and bid rates better, enhancing their project and risk management performance.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.153-160
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• 2009

The demand for super tall building construction is increasing worldwide. There has been a constant request for achieving early payback on investment by shortening the construction time. This pertains especially for the case of huge investment projects such as super tall building construction. It is very important to shorten the construction time for the building framework, which requires substantial construction time and cost, and this is directly related to the establishment of an optimum lift plan for construction. When there is a problem in the selection of the lift equipment, it is almost impossible to revise the selection, resulting in a possible failure of the project. Thus, the purpose of this study is to analyze the function and logic for the development of the process for the selection of lift equipment for super tall building projects and further development of making the analyzed process into a system. In line with this research objective, the process of selecting the optimum lift equipment by domestic construction company was investigated and analyzed as well as collecting the actual field data. The actual data were obtained by sensors installed on tower cranes at three construction sites with the help from the construction company.

• Journal of the Korean Society for information Management
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• v.24 no.3
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• pp.119-147
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• 2007

Actually a diffusion of a semantic web application and utilization are situations insufficient extremely. Technology most important in semantic web application is construction of the ontology which contents itself with characteristics of semantic web. Proposed a suitable a method of building web ontology for characteristics or semantic web and web ontology as we compared the existing ontology construction ana ontology construction techniques proposed for web ontology construction, and we analyzed. And modeling old ontology to bases to description logic and the any axiom rule that used an expression way of SWRL, and established inference-based web ontology according to proposed ways. Verified performance of ontology established through ontology inference experiment. Also established an web ontology-based intelligence image retrieval system, to experiment systems for performance evaluation of established web ontology, and present an example of implementation of a semantic web application and utilization. Demonstrated excellence of a semantic web application to be based on ontology through inference experiment of an experiment system.

• Industrial Engineering and Management Systems
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• v.14 no.3
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• pp.221-235
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• 2015

Risk assessment is an important phase of risk management. It is the stage in which risk is measured thoroughly to achieve effective management. Some factors such as probability and impact of risk have been used in the literature related to construction projects. Because in high-rise projects safety issues are paramount, this study has tried to develop a quantifying technique that takes into account three factors: probability, impact and Safety Performance Index (SPI) where the SPI is defined as the capability of an appropriate response to reduce or limit the effect of an event after its occurrence with regard to safety pertaining to a project. Regarding risk-related literatures which cover an uncertain subject, the proposed method developed in this research is based on a fuzzy logic approach. This approach entails a questionnaire in which the subjectivity and vagueness of responses is dealt with by using triangular fuzzy numbers instead of linguistic terms. This method returns a Risk Critical Point (RCP) on a zoning chart that places risks under categories: critical, critical-probability, critical-impact, and non-critical. The high-rise project in the execution phase has been taken as a case study to confirm the applicability of the proposed method. The monitoring results showed that the RCP method has the inherent ability to be extended to subsequent applications in the phases of risk response and control.