• Journal of the Korean Society of Safety
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• v.22 no.6
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• pp.63-68
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• 2007

The purpose of this study is to verify the relation between the risk index using AHP(Analytic Hierarchy Process) and the risk index using Computing Model. For doing the objective, this research classified 22 work types in architectural construction work from the analysis Korean architectural standard specification and Korea occupational safety & health agency code. Based on the classified 22 work types in architectural construction work, the risk index of each work type was calculated by AHP and Computing Model. For verifying the correlation of risk index between AHP and Computing Model methods, SAS version 8.0 System, which is one of the statistics programs, was used.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.3
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• pp.188-195
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• 2009

Generally. mobile sources of air pollution were classified in on-road and non-road. Due to increased registration number of construction equipment in Korea. updated emission factors for non-road mobile sources, such as construction machinery. should be developed. NONROAD model of U.S. EPA already has introduced transient adjustment factors and sulfur adjustment factors for emission factors of diesel powered engine. In addition to this. European Environment Agency (EEA) has proposed emission factors for off-road machinery including several types of construction equipment. In this study. six types of construction equipment, such as excavator. forklift, loader, crane, roller and bulldozer, were studied to estimate emission factors based on total registration status in Korea. Total 445 construction equipments between 2004 and 2007 model year were tested with KC1-8 mode and air pollutants (CO, THC, $NO_x$, and PM) were measured. After statistical estimation and calculation, emission factors for CO, THC, $NO_x$, and PM for excavator, forklift, loader, crane, roller and bulldozer were provided and compared with previous emission factors. Moreover, updated emission factors for six types of construction equipment in this study were verified after comparison with emission factors of U.S. EPA. Finally, estimated emission amounts of four air pollutants were suggested according to six types of construction equipment.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.10a
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• pp.7-14
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• 1989

This paper presents an expert system approach to solve preliminary bridge design problems. The system employs a forward chaining inference strategy to 1) choose the appropriate superstructure types and construction methods and 2) use the solutions chosen in 1) to determine a list of ranked alternatives. The basic information used in the selection is collected from various sources. Due to the uncertainties presented in the information collected, Fuzzy sets are used to handle these uncertainties in the system. Finally to approve this system some applications are made to select superstructure types and construction methods of them.

• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.98-103
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• 2016

The goals of this study were to investigate some significant factors to judge level of safety at urban railway construction field and to analyze degree of risk by work classification. Currently, there are lots of construction fields for the urban railway for national transportation, and our government also planned constructing more urban railway in near future. However, most of the researches on safety neglected the degree of risk factors on the urban railway construction field. Safety managers participated in the brainstorming session for deriving decision criteria of the degree of risk (i.e., significant factors). Then, they were asked to answer a structured questionnaire which was developed for deriving most important factors. Finally, the analytic hierarchy process (AHP) was used to analyze level of risk by work classification. The following results were obtained. First, total twelve factors judging degree of risk were found in the brainstorming session. Second, the questionnaire showed four significant factors, including adjacency of obstacle, intensity of work, unsafe condition and work space. Third, the results of AHP showed civil work is the most dangerous work among 6 work types. The results could be used to give the safety management priority on accident prevention efforts among several hazards and to reduce degree of risk in construction field of the urban railway.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.154-166
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• 2015

The in-core instrumentation measures core power distribution and coolant temperature in local regions of the core in pressurized water reactors. The installation types are distinguished by the designs of routing paths that exit either through reactor bottom mounted instrument nozzles or through reactor top mounted instrument nozzles. Although each type has unique advantages, it is generally known that top mounted design is more competitive with respect to emphasizing nuclear safety issues and ability to cope with severe accidents. The international nuclear vendors have provided various types of reactors with top mounted design. Nuclear power reactors in Korea, however, only have been designed to be applicable to the use of bottom mounted design, and it has been pointed out that the capabilities of Korean reactors against severe accidents should be further enhanced. The paper deals with technical issues on reactor internal and external design, in-core instrumentation, support assembly, sealing mechanism with nozzles, handling, and analytical issues in order to establish the ways of development.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.660-670
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• 2009

Neighboring construction becomes mainstream of Ground excavation in downtown area. This causes the displacement, deformation, stress condition, etc of the ground surroundings. Therefore Neighboring construction have an effect on Neighboring structure. All these years a lot of Neighboring construction carried out, and the accumulation of technology also get accomplished. But earth retaining structure collapse happens yet. Types of earth retaining structure collapse are 12. 1. Failure of anchor or strut system, 2. Insufficiency of penetration, 3. H-pile Failure on excessive bending moment, 4. Slope sliding failure, 5. Excessive settlement of the back, 6. Deflection of H-pile, 7. Joint failure of coupled H-pile, 8. Rock failure when H-pile penetration is rock mass, 9. Plane arrangement of support systems are mechanically weak, 10. Boiling, 11. Heaving, 12. Over excavation. But field collapses are difficult for classification according to the type, because collapse process are complex with various types. When we consider the 12 collapse field, insufficient recognition of ground condition is 4 case. Thorough construction management prevents from fault construction. For limitations of soil survey, It is difficult to estimate ground condition exactly. Therefore, it should estimate the safety of earth retaining system, plan for necessary reinforcement, according to measurement and observation continuously.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.95-99
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• 2013

The goal of this study was to investigate some significant factors to influence level of safety at plant construction field and analyze degree of risk by work classification. Currently, there are lots of construction fields for the nuclear power plant for electricity generation, and our government also planned constructing more nuclear power plant in near future. However, much of the safety literature neglected the degree of risk factors on the plant construction field. Safety managers participated in the brainstorming session for drawing decision criteria of the degree of risk (i.e., significant factors). Then, they were asked to answer a structured questionnaire which was developed for drawing most important factors. Finally, the analytic hierarchy process (AHP) was used to analyze level of risk by work classification. The following results were obtained. First, total twelve factors judging degree of risk were found in the brainstorming session. Second, the questionnaire showed four significant factors, including number of workers, working environments, skill of craft and accident experience. Third, the results of AHP showed Architecture work is the most dangerous work among 6 work types. The results could be used to reduce degree of risk in construction field of the nuclear power plant.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.729-734
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• 2022

Various studies using accident cases are being conducted to identify the causes of accidents in the construction industry, but studies on the differences between public and private construction are insignificant. In this study, web scraping and text mining technologies were applied to analyze the causes of accidents by order type. Through statistical analysis and word cloud analysis of more than 10,000 structured and unstructured data collected, it was confirmed that there was a difference in the types and causes of accidents in public and private construction. In addition, it can contribute to the establishment of safety management measures in the future by identifying the correlation between major accident causes.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.788-793
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• 2009

Constructing substructures by using Top-Down or Downward method needs an efficient formwork system because of difficulties in supporting concrete slabs from the bottom while excavation is in process. Existing underground formwork systems can be classified by three types: graded ground supported type (Slab On Grade, Beam On Grade), suspension type (Non Supporting Top Down Method), and bracket supported type (Bracket Supported R/C Downward). Each method has its own advantages and limits. Application of a specific formwork system for a given construction site is determined by various conditions and affect construction time and cost. This paper presents a newly developed underground non-supporting formwork system, which combines the advantages of a suspension type and a bracket supported type while it overcomes limits of two types. The developed system has a moving formwork which is supported by suspension cables hanging from the bracket placed at the top of pre-installed substructure columns. Then, the moving formwork is repeatedly lowered down for the next floor below to support concrete slab during curing. The details of this bracket and cable supported system have been investigated for the improvement of easiness in construction.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1117-1123
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• 2009

Compared with other industries, the construction Industry has many parties(A/E/C) as well as many types of construction activities. Especially, as for the remodeling project, the owner group the remodeling union consists of various stakeholders union and requiring the additional activities of demolition except for the existing new building construction project. Like this, the remodeling project has its own characteristics different from a new building construction project. As for the remodeling project, the Owner's decision making for a remodeling alternative has to be preceded, and other parties are required to propose a remodeling alternative which satisfies the Owner's requirements. However, because of time constraints, many types of problems occur during the decision-making process. In consideration of this, in this research, the authors would like to suggest a decision-making support system to help the Owner's decision-making in the early stage of a remodeling project. For this paper purpose of a remodeling decision-making framework based on Building Information Modeling(BIM) was suggested to help with the Owner's decision-making for each remodeling item and the decision-making support system was evaluated through Case Study.