• Journal of the Korean Geosynthetics Society
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• v.17 no.1
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• pp.111-118
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• 2018

In case of excavation of the tunnel under weak ground conditions, such as fault zone, leg pile reinforcement with the purpose of suppressing tunnel crown settlement and side wall displacement is commonly applied. There are convergence, crown settlement, leg settlement, and the axial force of leg as a main factor for confirming the safety of support considering the installation angle and length of leg pile reinforcement according to the increase in rate of change of tunnel cross-section. In particular, the influence of right corner settlement, among variables for safety confirmation during excavation, has been analyzed as the dominant factor in the most important priority management showing larger displacement tendency than the increase in rate of the cross-section. And, it was analyzed that the occurrence tendency of axial force on leg pile reinforcement showed the influence of behavior according to the friction support concept mechanism of the pile reinforcement rather than the increase in rate of tunnel cross-section, as it showed a small increase compared to the increase rate of the tunnel cross-section which did not show a great correlation from the viewpoint of the change of the axial force by the length of each leg pile reinforcement with regards to the change in rate of increase in tunnel cross-section. If a certain length of the leg pile reinforcement is selected based on the above grounds, even if the cross-section of the tunnel in poor ground condition is somewhat larger, it has been proved to be a more reasonable method considering the workability and economical efficiency by not extending the length of the leg pile reinforcement by force.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.307-323
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• 2003

In this study the pilot test of C.G.S (Compaction Grouting System) as injection method by low slump mortar was performed and the results were analyzed in order to find out the application of this method to the soft ground and the effect of settlement restraint. The site for pilot test is adjacent to apartments supported by pile foundations. Sand drain method was performed previously as countermeasures against settlement, but settlement occurs continuously because this ground is very soft. Site investigations such as SPT, CPT and vane shear test were performed to determine the characteristics of ground improvement after the installation of C.G.S. Field measurements were performed on purpose to find out the displacement of ground during the installation of C.G.S. From the results of this study, C.G.S method can be optimized by the control of radius, space, depth, injection material and injection pressure. C.G.S improves soft ground with radial consolidation of adjacent soft ground. Considering that increase of N value to about 3, C.G.S can be considered as an effective method to increase the bearing capacity as well as constrain the settlement of soft ground. It is also expected to be economic and effective in the improvement of ground when it is used in applicable sites.

• Journal of the Korean Geotechnical Society
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• v.21 no.10
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• pp.5-16
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• 2005

Geosynthetic-reinforced and pile-supported embankments have been increasingly used and researched around the world. The inclusion of one or multiple geosynthetic reinforcements over the pile is intended to enhance the efficiency of load transfer from soft ground to piles, to reduce total and differential settlement and increase global or local stability. In this paper, the reinforcement effectiveness and arching effect of the geogrid-reinforced and pile-supported embankments have been studied in terms of field model tests and numerical analysis with varying the space between piles and reinforcement. 2-dimensional numerical analysis has been conducted using the FLAC (Fast Lagrangian Analysis of Continua) program. And load transfer mechanisms between soil-piles-geogrid were investigated. The mechanisms of load transfer can be considered as a combination of embankment soil arching, tension geogrid, and stress concentration due to the stiffness difference between pile and soft ground. Based on the field model test and numerical analysis results, it was found that the geosynthetic reinforcement slightly interferes with soil arching, and helps reduce differential settlement of the soft ground. Also. at the D/b=3 (D: spacing of pile cap, b: diameter of pile), the total settlement is reduced by about $40\%$ compared to that without reinforcement. For $D/b{\ge}6$, the effectiveness of geogrid reinforcement in reducing settlement is negligible.

• Journal of the Korean GEO-environmental Society
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• v.14 no.9
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• pp.31-37
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• 2013

In this study installation diameter, interval, area replacement ratio and ground hardness of applicable ground in C.G.S method should be mastered through surrounding ground by conducting modeling. Optimum artificial neural network was selected through the study of the parameter of artificial neural network and prediction model was developed by the relationship with numerical analysis and artificial neural network. As this result, C.G.S pile settlement and ground settlement were found to be equal in terms of diameter, interval, area replacement ratio and ground hardness, presented in a single curve, which means that the behavior pattern of applied ground in C.G.S method was presented as some form, and based on such a result, learning the artificial neural network for 3D behavior was found to be possible. As the study results of artificial neural network internal factor, when using the number of neural in hidden layer 10, momentum constant 0.2 and learning rate 0.2, relationship between input and output was expressed properly. As a result of evaluating the ground behavior of C.G.S method which was applied to using such optimum structure of artificial neural network model, is that determination coefficient in case of C.G.S pile settlement was 0.8737, in case of ground settlement was 0.7339 and in case of ground heaving was 0.7212, sufficient reliability was known.

• Journal of Environmental Science International
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• v.13 no.2
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• pp.129-134
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• 2004

Understanding aspects of the use of Korean representative Soraksan National Park and investigating the factors affecting visitors' decision-making, this study aims to suggest a positive development plan for the rational use of the national park. The questionnaire is for those who have visited Soraksan National Park more than once. This research shows that most of the visitors wish ‘entrance congestion’ to be solved by introducing a ‘previous reservation’ system and a non-polluting shuttle bus; therefore there is a chance that they could be introduced for the settlement of the existing problems.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.618-624
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• 1999

For many soft ground embankment projects , instrumentation programs for stability and settlement management is being essential . This usually leads to generate large volume of data, which can be used for further research. Database technique is most effective method for data management . Data produced by soft ground embankment instrumentation can not be used by itself but must be reproduced using geotechnical analysis technique. In this study, a intelligent database system for softground called IDSIM was developed to examine applicability intellgent database. . The IDSIM analysis instrumentation data automatically and present results by Web/DB interface successfully.

• Journal of the Korean housing association
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• v.9 no.1
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• pp.55-62
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• 1998

The Purpose of this research is to identify management systems that effect to multi-family housing resident's management satisfaction. This study used survey data collected by Korea Reseach Institute for Human Settlement(KRIHS) in 1003. The major findings were as follows: 1) Residents in compulsary management system evaluated housing management higher than ones in optional management system. 2) Quality of mainternanace management and residents' reliability of the representative committee influenced to residents' overall satisfaction of housing management.

• Journal of East-Asian Urban History
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• v.3 no.1
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• pp.21-56
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• 2021

Though known for its connections with maritime trade at varying degrees before the rise of the Manchus and their Qing Empire, Newchwang as a fortress did not become a populous urban settlement in the nineteenth century when the Euro-American observers arrived. Through examining the history of this trade-related locale in the Qing Empire, this article explores the broader historical context, especially the Eight Banners System of the Manchus, which prevented Newchwang from developing into a port-city, and the implications behind.

• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.2
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• pp.43-56
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• 1987

The concept of ‘Open Space’ is conceived to be very valuable subject of interest in developing modern settlement system. In Korea, many new and old residential sites have been developed or renewed to fulfil the housing demands. And such trends seem to continue for the time being. What is more, the requirments for more comfortable residential environments, that is deeply concerned with ‘Open Space’, inorease gradually. As a basis for designing more efficent residential environments to fit Korean morden life style, self - grown, traditional and agricultural villages are studied. This study is concenturated on the Open Space System with its socio - cultural and physical backgrounds. For this, data and materials are some widely collected and are analysed focused on the systems and structures of ‘Open Spaee’. Some results from this study are summarized as follow ; 1. It is assumed that the number of houses per village is around 60, and that its area reaches to the radious of 3-4km. 2. ‘POONGSU’is a generally adopted theory based on natural elements like mountians, waters, and orientations when locating villages and composing their spatial structures. As a result of this, the basic structures of villages and Open Space are defined. 3. Circulation system is integrated to the hierachyal order system ; that is, Passing Road \longrightarrowEntry Road\longrightarrowCentral Read\longrightarrowDisperse and Access Road. 4. The natural and agricultural land uses are overlapped with diverse outdoor activities - religious services, play and recreation, relaxation, etc - without any physical modification. 5. At each villages, several artificial and spot - like green facilities are found. And distinctive functions, meanings, and locationalities are given to each of them. On that, they become a visual and psychological centers of each village. 6. In addition to its basic function of circulation, Central Road takes the sence of place for outdoor activities. Because of this charactor, it plays an important role of activating the village life and binding the various Open Space elements.

• Journal of Fisheries and Marine Sciences Education
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• v.13 no.2
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• pp.146-167
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• 2001

Korea and China are two opposite countries located aside Yellow Sea and co-utilize the East China Sea. The two countries are close together from geological point of view, however, the competitive development of resources was more emphasized than the cooperative development of resources between the two countries because the special policy relationship. Additionally, after the communist government of China was founded in 1949, the political conception between the two countries was quite different. Therefore the establishment of appropriate international fisheries co-operation was impossible, and the international management problems of fisheries resources in Yellow Sea and East China Sea were let alone. UN convention on the Law of the Sea came to force in 1994, Korea and China adopted the exclusive economic zone system in 1996. On the other hand, Fisheries Law in Korea was enacted in 1953 in order to management of fisheries resources, and also China was enacted fisheries law in 1986. The two countries control the fisheries effort through fisheries license system, meanwhile through prohibition fishing area, prohibition fishing period, limitation of net size, and limitation of body length to conserve and manage the fisheries resource. The serious management methods of resource management in the two countries are similar such as the creation of promptly decreased species and those species that have commercial value, discharge of fish seedling stock, settlement of artificial reef and clean of fishing ground. Therefore, the two countries should consider not only the improvement of formal law system, but also how to recover the fisheries resources in circumference water zone and how to improve the efficiency of fisheries resource management. Specially the settlement and management of artificial reef should be chosen in the area that have the highest benefit to two countries, and should establish the common management system of discharge of fish seedling stock. And the two countries should adopt the same criteria through technical management and limitation of net size, limitation of body length, and prohibition area of special fisheries to ensure the highest fisheries benefit of fisherman in the two countries and the highest efficiency of fisheries resource management.