• Journal of Construction Engineering and Project Management
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• v.8 no.2
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• pp.17-33
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• 2018

This study investigates the stability of professionals' cost variability factor-rankings across different levels of cost-variability and response scenarios. Descriptive statistics are used to examine the stability of factor-ranking for 20 cost variability factors and a Multinomial Logistic (MNL) regression model was implemented to examine the stability of cost variability factors across three cost variability levels. The finding on the descriptive statistics indicated that professionals' factors-rankings are stable only for external factors. The MNL regression results on factor-stability suggested that 8 out of the 20 evaluated factors were unstable determinant of lower cost variability levels. These factors are "risk associated with the project", "personal bias and poor professionalism of the estimators", "limited time available to complete the project", "lack of skills and experience by estimator" "geographical location of projects", "incomplete & rush designs for estimate", "unforeseen or unexpected site constraints", "high class bidders for the contractors". Similarly lack of experience and large size projects were observed to be unstable as well. These observations suggest that professionals' view on pre-tender cost variability factor-ranking yields unstable factor rankings hence should not be relied upon as the only mechanisms to mitigate cost related risks in construction projects.

• Advances in Computational Design
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• v.5 no.4
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• pp.445-465
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• 2020

This paper presents a study conducted with the aim of developing a model of tendering based on a technique of artificial intelligence by managing and controlling the factors of success or failure of construction projects through the evaluation of the process of invitation to tender. Aiming to solve this problem, analysis of the current environment based on SWOT (Strengths, Weaknesses, Opportunities, and Threats) is first carried out. Analysis was evaluated through a case study of the construction projects in Algeria, to bring about the internal and external factors which affect the process of invitation to tender related to the construction projects. This paper aims to develop a mean to identify threats-opportunities and strength-weaknesses related to the environment of various national construction projects, leading to the decision on whether to continue the project or not. Following a SWOT analysis, novel artificial intelligence models in forecasting the project status are proposed. The basic principal consists in interconnecting the different factors to model this phenomenon. An artificial neural network model is first proposed, followed by a model based on fuzzy logic. A third model resulting from the combination of the two previous ones is developed as a hybrid model. A simulation study is carried out to assess performance of the three models showing that the hybrid model is better suited in forecasting the construction project status than RNN (recurrent neural network) and FL (fuzzy logic) models.

• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.121-133
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• 1997

EIA should be regarded as an aid to improve the decision making processes because it seeks public opinion and external knowledge in order to ensure the maximum degree of fairness and balance in the final decision as much as possible. According to the above benefits, various decision making systems containing EIA concepts were developed in the area of ground water, traffic, disaster or accident and environment in Cheju Island. But because the development of various decision making systems can be the cause of new impact, it was studied the cause and impact of their development. The major reasons for developing the various decision making system like EIA are the lack of the consideration for the impact of project when it is selected project fulfilling EIA and the increase of the effort for the improvement in the professional quality for one subject without the comprehensive assessment among the subject related to environmental impacts. And the development of the various decision making systems like EIA has caused the several impacts like cost elavoration, the relay of project period, etc. Therefore, after it is improved the problems of present EIA on the comprehensive assessment, the various decision making systems like EIA should be integrated in EIA decision making system.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.90-96
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• 2005

This paper presents the results of the reliability analysis of PAU (Preliminary Assembly Unit) seat of the floating Production Storage and Off1-loading Unit (FPSO) The main aim of the analysis was to demonstrate that a sufficient safety of structural members is guaranteed against PAU loads, internal and external pressure, and hull girder moments. Topside loads for PAU design are based on owner's request. According to the seat type, topside loads are classified into maximum values of same seat type for design efficiency. Totally, 26 loading cases for each model are used for this analysis with the combination of the reactions of PAU loafing and the hull girder bending moments according to LR offshore (2). The analysis results are evaluated according to the acceptance criteria for yielding given in LR offshore and guidance note (3) and The panel buckling resistance is verified by LR offshore and SDA (4). For 900,000 bbls FPSO, the PAU support foundation analysis using 3-D F.E. model is carried out to verify the structural adequacy of PAU foundation and structure members in way of PAU. The modified structures in way of PAU support are safe against considered load cases and all stresses in way of PAU support are within design criteria.

• Journal of the Korea Society of Computer and Information
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• v.13 no.3
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• pp.139-146
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• 2008

Despite of information security installation, leakage of personal information in web services has not decreased. This is because traffics to web applications are still vulnerable by permitting external sources to access services in port HTTF 80 and HTTPS 443, even with firewall systems in place. This thesis analyzes various attack patterns resulted from web service environment and vulnerable traffic and categorizes the traffics into normal and abnormal traffics. Also this proposes ways to analyze web application attack patterns from those abnormal traffics based on weak points warned in OWASF(Open Web Application Security Project), design a system capable of detect and isolate attacks in real time, and increase efficiency of preventing attacks.

• Journal of the Korean Institute of Rural Architecture
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• v.26 no.3
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• pp.11-18
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• 2024

As the complexity and diversity of modern urban development increases, the importance of external space planning in urban development projects is growing. This study analyzes the importance and characteristics of each major to enhance the utility value of external space, which aims to improve the efficiency of external space planning and ultimately improve the quality of life of residents. To this end, we reviewed relevant literature, legal guidelines, checklists, and guidelines, and derived 17 external space indicators through expert surveys and FGIs, and organized them into five major categories: accessibility, connectivity, suitability, stability and locality, and landscape planning through FGIs with experts in architecture, urbanism, and landscape architecture. As a result of the analysis, urban planning and design majors prioritized planning that considers the hierarchy and characteristics of the landscape structure, securing public space through the connection of open spaces and pedestrian paths, and connecting organic and three-dimensional buildings, streets, and parks; architectural planning and design majors prioritized harmony with the surrounding environment, securing public space through the connection of open spaces and pedestrian paths, and connecting organic and three-dimensional buildings, streets, and parks; and landscape (environmental) and landscape majors prioritized harmony with the surrounding environment, connecting with adjacent buildings, streets, parks, and green spaces, and planning with integrated landholdings. This emphasizes that urban development projects should secure publicness and integration through harmonious connections with adjacent buildings, streets, parks, and green spaces. This study developed evaluation indicators for evaluating the external space planning of urban development projects and quantified them through the hierarchical analysis method (AHP), which will be useful for future policy formulation and practical application in the fields of urban planning and design, architectural planning and design, landscape (environment), and landscape architecture.

• Korean Journal of Construction Engineering and Management
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• v.1 no.2 s.2
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• pp.71-80
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• 2000

Project delivery systems determine the relationship, responsibility, authority and the scope of works of those involved in project, hence, optimum project delivery system should be selected to so that construction project would be executed successfully, Until now, the traditional design-bid-build mainly has been used for public projects, but the government is making efforts actively to introduce other methods such as design-build, alternative bidding by its policy. However, delivery systems should be determined through considering physical projects characteristics, owner's goals, external factors, etc, rather than government' policy. Therefore, the purpose of this research is to propose objective delivery system selection criteria and delivery system selection model, which help owners to select the suitable delivery system through quantitative and reasonable manner.

• Biomedical Science Letters
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• v.15 no.3
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• pp.249-255
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• 2009

All living things have been developed efficient strategies to cope with external and internal environmental changes via a process termed 'homeostasis'. However, chronic prenatal maternal stress may significantly contributes to pregnancy complications by disturbing hypothalamic-pituitary-adrenal (HPA) axis and the automatic nervous system (ANS), and results in unfavorable development of the fetus. Dysregulation of these two major stress response systems lead to the increased secretion of the glucocorticoids (GCs) which are known to be essential for normal development and the maturation of the central nervous system. As Hox genes are master key regulators of the embryonic morphogenesis and cell differentiation, we aimed to determine the effects of dexamethasone, a potent synthetic glucocorticoid, on gene expression in mesenchymal stem cell C3H10T1/2. Analysis of 39 Hox genes based on reverse transcription PCR (RT-PCR) method revealed that the expression patterns of Hox genes were overall upregulated by long dexametasone treatment. These results indicate that maternal stress may have a deleterious effect on early developing embryo through the stress hormone, glucocorticoid.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.347-356
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• 2020

Mechanization and automation constitute an essential stage in the production and operation of any company, as one of the determinants of increase in labor productivity and decrease in product price, while significantly contributing to shortening of the lead time. Businesses are, therefore, able to quickly put projects into operation, improving economic efficiency, quality, and aesthetics, which speeds up the national economic growth. For the construction industry to be the most effective, modern construction equipment is a necessity. It is one of the five main resources of a construction project. Thus, effective construction equipment management contributes to the success of a project and benefits the relevant construction companies economically. This paper presents the critical risk factors affecting equipment management and proposes suitable solutions. The questionnaire-based survey with experienced experts in the construction sector on the management of the likelihood and consequence of risk factors revealed thirty-two risks for equipment management in construction companies. These factors fell into six groups: (i) site organization-related risks; (ii) management-related risks; (iii) owner-related risks; (iv) supplier-related risks; (v) legal risks, and (vi) site condition-related and external risks. The results showed that management-related factors contributed to the most significant risks and problems for equipment management in construction companies.

• Journal of information and communication convergence engineering
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• v.8 no.5
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• pp.528-533
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• 2010

This research is part of the development of Data Acquisition embedded system that specifically use in ship. The purpose of this data acquisition system mainly is to acquire data from multiple sensors or others related external devices and it will further discuss in this paper. The data collecting, hardware design, software design and the final project outcome of this data acquisition system will be discussed in this paper.