• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.530-540
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• 2013

The business environment that affects the management performance can be characterized by each Strategic Business Unit (SBU) since construction companies win overseas contracts due to the fairly good construction situations while experience a decline in the local housing market. Environmental changes can alter the strategic importance of the SBU when measuring the management performance. However, large construction companies apply BSC (Balanced Score Card) for collective calculation to determine the management performance, making it difficult to reflect the strategic importance of SBU. This method may create a distorted image of management performance that fails to take environmental changes into consideration, and as such it needs to be improved. Yet, there are no studies on the weight of each SBU considering environmental changes. Thus, the current study intends to analyze the weight of SBU for company-wide measurement of the performance of large construction companies. In addition, a model for analysis of SBU importance is proposed to respond to the constantly changing environmental situations and to modify the weight. For analysis of SBU weight, a questionnaire was conducted with 23 experts and hands-on workers, and the questionnaire result was quantitatively analyzed by applying the FD-AHP method. It is expected that the result will enable a model to be proposed to calculate the weight per division in a manner that reflects environmental changes and minimizes strategic distortion when measuring the management performance of large construction companies.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.517-528
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• 2013

The modular technology has been already applied in automotive industry, plant and shipbuilding industry. Recently, the modular technology was applied in bridge construction. The modular bridge is different from the existing precast bridges in terms of standardized design that the detailed design of members is omitted by using the standard modules; the design of the modular bridge is completed by only assembling the standard modules without design in member level. The girder-type precast modular bridge has been developed as a simply supported bridge. The girder-type precast modular bridge could be applied to the multi-span bridges through the continuity method. The continuity of the girder-type precast modular bridge is achieved by using the link slab which is easy to construction and appropriate to the rapid construction. The link slabs have been used as the type of reinforced concrete structure in US from the 1950's. In 2000's, the link slab using the engineered cementitious concrete (ECC link slab) has been developed. In this study, the RC type link slab which is more reproducible and economic relative to the ECC link slab was used for the continuity of the girder-type precast modular bridges, and the construction detail of RC type link slab was modified. In addition, the modified iterative design method of RC type link slab was proposed in this study. To verify the proposed design method, the flexural tests were conducted using the RC type link slab specimens. Also, the fatigue test using the mock-up specimen was conducted with cyclic loading condition up to two million cycles.

• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.37-45
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• 2000

The underground buried pipelines of Natural gas are relatively safer than any other pipelines of chemical plants, because Natural gas is non-corrosive fluid. But Natural gas is supplied normally the downtown area. So, it may be a disaster because of corrosion which is caused interference facilities, environment and third party accident which is caused facilities construction. Especially, it is very difficult to find out and inspect damages of pipeline because of buried pipelines. Therefore this paper approached to select and manage risk region pipelines according to introduction of underground buried pipeline's risk concept. Risk was indicated three parts - corrosion factor, design and construction factor, maintence and management factor - in this paper, Therefore qualitive risk of pipelines showed score as quantitative number. Also it was thought to be helpful in confidence and safety management that the concept of key index and failure supplementation measures to cost introduces this program. We developed this risk assessment program using visual basic tool and interfaced GIS.

• Journal of Korean Society of Steel Construction
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• v.24 no.6
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• pp.701-710
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• 2012

We present optimum design for truss and frame structures subject to constraints on stresses, displacement, and natural frequency. The optimum design procedure is used discrete and continuous design variables and Genetic Algorithms. Genetic Algorithms is used the method of Elitism and penalty parameters in order to improved fitness in the reproduction process, and optimum design is used steel(W-section) and pre-made discrete cross-section. Truss and frame structures optimization examples are used for 10-Bar truss, 25-Bar truss, 1-bay 2-story frame, 1-bay 7-story frame, and these examples are employed to demonstrate the availability and serviceability of Genetic Algorithms for solving optimum design of truss and frame.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.125-130
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• 2017

Automotive materials and plant modules need to be prepared for freezing parts to operate in extreme areas such as Eastern Europe, Russia, and Canada. However, the only thing that has been done for ultra-qualifying materials for extremely low operating materials is that only the effects at low temperatures are conducted at room temperature, and the effects at low temperatures are only identified at low speeds. Therefore, this study examined the low-temperature characteristics of materials by conducting comparative tests on the mechanical properties of the room at the temperature and temperature of TP304 and TP316 materials, which are the most common materials.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.312-320
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• 2020

3D scanning began in the field of manufacturing. In the construction field, a BIM (Building Information Modeling)-based 3D modeling environment was developed and used for the overall construction, such as factory prefabrication, structure construction inspection, plant facility, bridge, tunnel structure inspection using 3D scanning technology. LiDARs have higher accuracy and density than mobile scanners but require longer registration times and data processing. On the other hand, in interior building space management, relatively high accuracy is not needed, and the user can conveniently move with a mobile scan system. This study derives considerations for the development of Simultaneous Localization and Mapping (SLAM)-based Scan Backpack systems that move freely and support real-time point cloud registration. This paper proposes the mobile scan system, framework, and component structure to derive the considerations and improve scan productivity. Prototype development was carried out in two stages, SLAM and ScanBackpack, to derive the considerations and analyze the results.

• Journal of the Korean Geotechnical Society
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• v.21 no.10
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• pp.61-71
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• 2005

Cemented Sand and Gravel (CSG) is a material made by simple mixing of rock-based raw materials such as excavated soil and riverbed gravel together with cement and water. The use of CSG material for cofferdam and large dam is gradually increasing in Japan because a quarry and aggregate plants can be diminished. Also, the CSG method can reduce dam construction cost, construction duration and destruction of environment. In this paper, the basic strength characteristics of CSG, such as compressive strength, modulus of elasticity and stress-strain curve were investigated by unconfined compression test and large triaxial compression test. From the results of the experimental study, the correlation equations between elastic modulus and unit cement, age are proposed.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.426-426
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• 2018

제 4차 산업혁명의 시대를 맞아 ICT 융합 차세대 물관리 시스템 관련 기술이 핵심적인 역할을 수행하게 될 것으로 예상되며, 이와 함께 다국적 기업의 시장 진출로 인한 경쟁심화가 예상되고 있다. 한편, 인구증가, 도시성장, 산업발전 및 기후변화에 따른 물부족, 물 수요와 물 공급의 불균형, 수질오염 등은 점점 더 심각해질 것으로 예상되고 있다. 또한, 수자원 산업에서 대상시설의 안전하고 경제적인 운영 및 유지관리를 목적으로 하는 운전, 감시, 진단, 보수, 개선 및 이를 위한 의사결정지원 기술인 운영관리(O&M, Operation and Maintenance) 기술의 중요성이 지속적으로 증가하는 추세이다. 스마트워터그리드(SWG)는 ICT 융복합 첨단 수자원 관리기술로 기후변화에 의한 물 부족과 수자원 인프라 노후화로 인한 효율저하 등 물 문제 해결을 위한 차세대 플랫폼으로 주목받고 있으나, 아직까지 스마트워터그리드 시스템 구축을 위한 장치, 부품, 공정, 설계, 시공 기술 등 주로 요소기술 확보를 목적으로 연구되었으며, 시설의 운영 및 유지관리 연구는 거의 진행되지 않아 효율적인 현장적용이 어려운 실정이다. 본 연구에서는 스마트워터그리드 데모플랜트 시설을 대상으로 운영 유지관리 기술의 고도화 기본방향, 세부 핵심기술, 추진방법 등을 제시하고자 한다. 특히 스마트워터그리드의 핵심기술인 AMI 기반 수운영 시스템을 대상으로 IoT 기반의 고효율 저비용 물 공급 체계 고도화 및 지능형 통합 운영 플랫폼 구축, Hybrid형 다중수원 활용 이동식 물 생산 시스템에 대한 운전제어 자가진단 운영관리 유지보수기술 등 원격 무인 자동화 물 생산시설 기술 고도화 개발방안에 대하여 중점적으로 다루고자 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.211-217
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• 2019

Oil extraction from oil sands, a non-traditional crude oil resource, is attracting attention as the oil price fluctuates due to recent economical and political issues. Many oil sands sites are mainly located in the polar regions. For plant construction to extract crude oil from oil sands in harsh environment of the polar regions, fast and simple installation of plant foundation is necessary. However, typically-used conventional foundations such as drilled shafts and driven piles are not suitable to construct under cold temperature and organic surface layers. In this study, helical piles enabling rapid and simple constructions using small rotary equipment without driving or excavation was considered. The helical pile consists of steel shaft and several helices attached to the steel shaft; therefore, the behavior of the helical pile depends on the number and shape of the helices. The effect of the helices' configuration (number and diameter of helices) on helical pile behavior was analyzed based on the numerical analysis results.

• Explosives and Blasting
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• v.40 no.2
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• pp.25-34
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• 2022

Recently, there has been an increasing number of cases of improving constructability by using electronic detonators with precise delay time in tunnel blasting sites. This case is a case of conducting test blasting using with non-electric detonator and electronic detonator at the site of 『Seoul Metropolitan Area Express Railroad Route A Private Investment Project Section 00』 that requires careful management of vibration and noise. Although this site was designed with a non-electric detonator, it was attempted to improve the advance rate and control vibration and noise by mixing the non-electric detonator and the electronic detonator due to the decrease in the advance rate. As a result of the blasting, the target value was achieved with an advance rate of about 85% and a maximum measured value of vibration and noise is 0.215cm/sec and 73.22dB(A) which were measured below regulatory standards. As blasting works in downtown areas, it is necessary to designate measurement and management objects to continuously manage vibration and noise.