• Journal of Astronomy and Space Sciences
• /
• v.41 no.1
• /
• pp.17-23
• /
• 2024

The safety of electronic components used in aerospace systems against cosmic rays is one of the most important requirements in their design and construction (especially satellites). In this work, by calculating the dose caused by proton beams in geostationary Earth orbit (GEO) orbit using the MCNPX Monte Carlo code and the MULLASSIS code, the effect of different structures in the protection of cosmic rays has been evaluated. A multi-layer radiation shield composed of aluminum, water and polyethylene was designed and its performance was compared with shielding made of aluminum alone. The results show that the absorbed dose by the simulated protective layers has increased by 35.3% and 44.1% for two-layer (aluminum, polyethylene) and three-layer (aluminum, water, polyethylene) protection respectively, and it is effective in the protection of electronic components. In addition to that, by replacing the multi-layer shield instead of the conventional aluminum shield, the mass reduction percentage will be 38.88 and 39.69, respectively, for the two-layer and three-layer shield compared to the aluminum shield.

• Journal of the Korean GEO-environmental Society
• /
• v.17 no.11
• /
• pp.45-53
• /
• 2016

A precast panel wall system resists against the horizontal earth pressure by increasing the shear strength of ground by reinforcement connected to the panel. The application of precast panel wall system is growing to lately minimize the earth work and environmental damage caused by large cut slope and to use the limited land effectively. The ground adhered panel wall system is the construction method that has the panel engraved with natural rock shape to improve the landscape. This system is developed to complete Top-Down method, and it is possible to have vertical cut, and to adhere to in-situ ground, improve construction ability by minimizing the ground relaxation and exclusion the trench and backfill process. In this study the field tests were performed to verify the construction ability about the vertical cut and complete Top-Down process and the construction behavior of ground adhered panel wall system was analyzed by large scale loading test and measurement results during loading test.

• Journal of the Korean earth science society
• /
• v.27 no.6
• /
• pp.659-669
• /
• 2006

In Kwangyang Bay, the south coast of Korea, surface sediments and sedimentation rates have been investigated to understand the distribution and variation of tidal flat sediments after the construction of sea dyke. The mean grain size of the surface sediments during autumn is coarser, and decrease from winter to summer except for temporarily coarsening in the early summer. The depositional processes are prevalent in spring, while erosional processes are dominant in summer and autumn. This seasonal variation of sedimentary processes show similar results monitored from 2001 to 2003 before the construction of sea dyke. In the northern area of the bay, net annual sedimentation rates show similar results monitored from 2001 to 2003 before the construction of sea dyke. However, in the western area of the bay, net annual sedimentation rates change from erosion-dominated to deposition-dominated environments. It is considered that the western area of the bay is changed to erosion-dominated environments, as a result of the changes of hydrodynamic conditions, caused by sea dyke construction.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2007.11a
• /
• pp.347-352
• /
• 2007

Recently, automated construction machines have been developed for technically solving construction industry problems such as labor, productivity, quality and the profit decrease. In domestic construction industry, a research for developing an intelligent excavation robot has been performed. The primary objective of this research is to analysis state-of-the art technologies in order to recognize local ground shape in real-time and compute soil volume of earth moving. This research analyzed five elemental technologies for 3D modeling of local ground shape and selected an optimal technology among the five technologies through using AHP method. It is anticipated that the optimal technology selected for 3D modeling of local ground shape can be effectively used to develop the intelligent excavation robot.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2003.11a
• /
• pp.170-175
• /
• 2003

Ground and rock mass considered in tunnelling have characteristics such as uncertainty, heterogeneity and structural complexity because they have been formed undergoing various geological events for a long period. So, it is difficult for engineers to predict behaviors of rock mass in tunneling. In the paper the authors describe the development of an integrated expert system prototype for site investigation, design and construction in tunnelling and introduce the case applying this system to the tunnel construction site under construction. Geostructure Research Group in Korea Institute of Construction Technology (KICT) has developed the system during the past 4 years. The system mainly consists of several modules which is related to the design, construction and management of tunnelling. The test site, Neung-dong tunnel is located in Ulsan, Korea. The geology map shows it may confront big fault zone whose width is over kilometres. With the networking system of ITIS, various information of face mapping, monitoring and other construction task can be transmitted into the database and GIS Server at real time. And necessary analyses can be carried out with the modules equipped in the system.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2007.11a
• /
• pp.722-727
• /
• 2007

As the world construction market is rearranged by the level of technological capability, recently the technological capability in construction industry is developing rapidly. The important of measuring and analyzing technological capability in construction industry is gaining more and more emphasis. It enables to grasp the past and present situation of construction industry as well as to foresee changes in the future. However the concept of technological capability cannot be identified easily, as well as it is hard to compare that capability of construction industry among different countries. Although there have been numerous studies conducted on the technological capability of construction industry, most of the studies were in formsof surveys of specialists or industry professionals which lacked objectivity and sound basis for data. This study will be focused on investigating the methodology in exploiting and measuring surface of the earth and developing indicator and process to understand technological capability in construction industry through quantitative and statistical analysis. Then it will verify them through a case study.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.25 no.1
• /
• pp.82-99
• /
• 1997

The purpose of this study is to establish work classification system of landscape construction in order to offer the basis of new estimation system of public landscape construction. New estimation system is based on historical construction data. For application of this system, the standard work classification system is necessary. Because extensive cost data should be accumulated under an unified construction work classification system. In the study of new estimation system carried by KICT(Korea Institute of Construction Technology), landscaping works belong to earth work of civil engineering. It looks very unreasonable work classification, because landscape archtecture has its own specialties and professional domain. In this study, information classification systems in the construction industry and various landscaping works of housing developments are analysed. As a result. a standard work classification system of housing landscape construction is proposed in section VI-3. This standard work classification structure consists of three levels divisions (i.e large work division, middle work division, small work division) . Now in this study, housing landscape construction works are divided into four large works and twenty six middle works. According to work attributes, middle and small work division is possible to subdivide into details.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.1206-1211
• /
• 2010

Soil-cement, a hardened mixture of Portland cement, soil, and water that contain sufficient durability, has been widely utilised in Seoul urban construction sites to retain lateral earth pressures or reinforce grounds. However, little information has been reported about the strength characteristics of soil-cement constructed in Seoul urban area. In this study, we performed a number of unconfined test to the soil-cements mixed from soils sampled in 3 sites in Seoul urban area. Results indicate that unconfined strengths and optimum cement amounts of soil-cements are highly dependent on the proportion of coarse-grain particles of mixed soils. Furthermore, changes of unconfined strengths with curing time are diverse with respect to mixing conditions.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2003.11a
• /
• pp.184-191
• /
• 2003

In this paper, a mathematical framework based on a homogenisation technique to simulate 'umbrella arch reinforcement system' (UARS) and its implementation into a 3D Finite Element program that can consider stage construction situations are presented. The constitutive model developed allows considering the main design parameters of the problem and only requires geometrical and mechanical properties of the constituents. Additionally, the use of a homogenisation approach implies that the generation of the Finite Element mesh can be easily produced and that re-meshing is not required as basic geometrical parameters such as the orientation of the pipes are changed. The model developed is used to simulate tunnelling with the UARS. From the analyses, the effects of the main design parameters on the elastic and the elastoplastic analyses are considered.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.21 no.4
• /
• pp.53-60
• /
• 2007

In this study, an experiment on the efficient construction method of plate electrodes, the influence of electric potential interference in plate electrodes, and building foundations were explored. The experimental result of the electric potential measurement was taken on the basis of the direction of movement and the condition in which the plate electrodes are laid underground in building foundations. It shows that the construction method of laying the plate electrodes vertically exhibits a more efficient reduction of electric potential in a diagonal direction and on an X axis than laying plates horizontally. For plate electrode construction in an area that has uniform conditions, the parallel joint construction method is more effective than a single construction to reduce earth electrical potential and ground resistance. In addition, a straight arrangement performs well in ground efficiency, compared to the parallel arrangement.