• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.19 no.2
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• pp.114-117
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• 1990

• Magazine of the Korean Society of Agricultural Engineers
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• v.7 no.1
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• pp.903-907
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• 1965

• International Journal of High-Rise Buildings
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• v.9 no.3
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• pp.301-306
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• 2020

In tall building construction, the appropriate control of lifting loads on tower cranes is critical in terms of the construction duration of structural works. The adoption of efficient construction methods can be the most effective way of minimizing the inputs of tower cranes and making a lifting plan and management easier. Based on actual data from a tall building project, this study comparatively analyzes lifting loads of tower cranes by the core structure preceding construction method (CSPCM) and the core structure succeeding construction method (CSSCM). The results revealed that the CSSCM could reduce up to about 56.3% of lifting loads for core works and significantly enhance lifting efficiency compared with the CSPCM. Consequently, this enabled a substantial reduction in the construction duration of structural works. This study provides a practical reference to assist engineers and managers in applying efficient construction methods and lifting equipment operation in tall building projects.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.333-338
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• 2001

Fault tree is a widely used methodology for analyzing product reliability. The fault trees are usually constructed using the experiences of expert reliability engineers in top-down approaches and have different structures according to each expert's subjectivity. In this work it is tried to find a general method for the fault tree construction based on the function tree that is the result of product function deployment. Based on the function tree, the method has the advantage of resulting an objective fault tree since the faults are defined as the opposite concept of functions. The fault tree construction of this work consists of the following steps: 1) definition of product primary function with the viewpoints of product operation and configuration, 2) construction of functional relation chart using a grouping algorithm, 3) abstraction of functional block diagram according to operation sequences and configuration of a product, 4) construction of function tree for each viewpoint, and 5) construction of fault tree by matching the function tree and simplification of the result.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1294-1301
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• 2010

In this study, a case study, where a hazard management for tunnel collapses has been quantitatively undertaken based on the KICT Tunnel Hazard(KTH) index, is presented. From this, it was able to timely inform the field engineers when the more detailed investigation is required for checking if any risky factor is shown on the tunnel face. At the same time, variable additional information such as sensitivities of major influence factors are also provided to field engineers from the methodology given in this study. The additional information would be helpful for better understanding of tunnel hazard level at the current tunnelling stage and following the required actions for more detailed checks of risky factors.

• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.4
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• pp.31-41
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• 1985

This paper compares the estimated total construction and maintenance costs for irrigation canals in six irrigation districts near Pyongtaek. Three conventional canal types were considered: concrete bench flumes, concrete-lined canals, and earth canals. The total expenses for each type were grouped to four catagories: the net construction, land acquisition, maintenance, and other expenses. The construction costs included the assumed costs for conveyance losses from each type of canals. The results from this study support earlier studies that the bench flumes are economically feasible. Initially cheaper conveyance systems like concrete-lined and earth canals demand 'higher maintenance costs and thus, their total expenses are summed to exceed those for the bench flumes within a few years following the construction. Banch flumes are economically justifiable for the main canals of the studying districts. Sensitivity analyses were executed to evaluate the relative importance of each expense to the total cost. The analyses show that total expenses very significantly with the change of the following costs: cost for conveyance losses, net construction, maintenance, and land acquisition, in that order However, other expenses contribute little if not at all to the total. The results indicate that bench flumes should be adopted as main canal structures for most irrigation districts in the Republic.

• Journal of the Korea Institute of Building Construction
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• v.12 no.6
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• pp.674-681
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• 2012

With the rise in the functions required in modern building structures, the role of the building equipment that maintains the functions of a building has been emphasized and increased. Effective management in this area is only possible when the construction manager (CMr) is qualified and has the knowledge of building equipment that is needed. Therefore, in this study, a questionnaire survey was carried out on equipment engineers and CMrs, in order to determine the level of building equipment knowledge required, and to identify the perception level of CMrs about the building equipment in the construction project at the project design stage. The results of this study revealed that the CMrs surveyed had a lower level of knowledge on the building equipment than the level that was desired by the equipment engineers. This indicates that CMrs currently have a weak capacity for the management of building equipment. It is thus necessary for CMrs to undergo systematic training in order learn more about building equipment and thus be able to manage construction projects more efficiently.

• Land and Housing Review
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• v.11 no.3
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• pp.93-101
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• 2020

Recently, as a BIM-based construction simulation system, 4D CAD tools using virtual reality (VR) objects are being applied in construction project. In such a system, since the expression of the object is based on VR image, it has a sense of separation from the real environment, thus limiting the use of field engineers. For this reason, there are increasing cases of applying augmented reality (AR) technology to reduce the sense of separation from the field and express realistic VR objects. This study attempts to develop a methodology and BIM module for the pre-construction verification system using AR technology to increase the practical utility of VR-based BIM objects. To this end, authors develop an AR-based drawing verification function and drawing object-based 4D model augmentation function that can increase the practical utility of 2D drawings, and verify the applicability of the system by performing case analysis. Since VR object-based image has a problem of low realism to field engineers, the linking technology between AR object and 4D model is expected to contribute to the expansion of the use of 4D CADsystem in the construction project.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1032-1039
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• 2022

Evaluating infrastructure's impact on social equity is an emerging area of research in transportation construction engineering. Transportation agencies have been trying to include sustainable development. The three components of sustainable development are environmental protection, social equity, and economic development. Although social equity is one of the essential components of sustainable development, most transportation agencies do not consider this component. The research publications in this area are limited. The principal objective of this study is to synthesize existing studies related to the impact of transportation infrastructures on social equity. This study will also identify social equity indicators, the correlation between social equity and transportation infrastructures and their services, and the impact of transportation infrastructures' on social equity. In addition, this study will identify current issues of social equity and will provide some recommendations. This synthesis study revealed that transportation infrastructures impacted social equity in various ways. Some effects are positive, such as new job creation on the market. Other effects are adverse, such as diminishing socio-economic and environmental degradation. Studies also showed that the current practices evaluated infrastructures' impact on a case-by-case basis. The authors recommend adopting a multi-disciplinary holistic for assessing infrastructure's effects on social equity. The multi-disciplinary fields of study include civil engineers, construction engineers/managers, public policy researchers, environmentalists, and social scientists.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.65-69
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• 2015

The aim of this paper is to identify and rank the main causes of fall accidents from scaffolding according to their relative importance as perceived by project managers and site engineers in construction projects in the Gaza Strip. A total of 50 questionnaires were distributed to project managers and site engineers, 35 questionnaires were received yielding 70% response rate. A total of 33 factors that cause fall accidents in scaffolding were identified through a literature review and consolidated by a pilot study. These factors were categorized into six groups: factors related to erection, factors related to the staff (Scaffolders), factors related to loads, factors related to the personal safety, factors related to the workers behavior, factors related to the personal competencies. The results indicated that factors related to the workers behavior are the major factors that caused fall accidents from scaffolds. The results revealed that the top ranked factors which caused falls accidents from scaffolding were: absence of personal protective equipment (PPE), missing ladders, wind loads, disguised the design code, lack of proper assembly or inspection, overhead tools and materials, climbing and neglect using ladders, lack of guardrails, missing bracing and working during fatigue. These findings would help contractors to understand the top factors that caused fall accidents so that they can take them into consideration in safety planning in order to minimize the possibility of their occurrences.