• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.103-108
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• 2003

In the construction of mountain tunnels, reaction forces of the legs of steel arch supports against the ground are often expected to support the ground being excavated. In these cases, a stress concentration occurs in the ground directly under the support legs. If the bearing capacity of the ground is insufficient or displacement is not effectively constrained, the local failure of the ground under the support legs or settlement of the tunnel supports due to large deformation could result. It is therefore necessary to reinforce the support legs to reduce settlement. As a means of reducing settlement, wing-ribbed steel arch supports are well used. In this study, with the aim of finding a way to quickly reduce the settlement of steel arch support legs, effectiveness of a new type of wing ribs to reinforce steel arch supports was investigated through laboratory testing.

• Geomechanics and Engineering
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• v.12 no.2
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• pp.313-326
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• 2017

Based on the reliability theory and limit analysis method, the roof stability of a shallow tunnel is investigated under the condition of surface settlement. Nonlinear Hoek-Brown failure criterion is adopted in the present analysis. With the consideration of surface settlement, the internal energy and external work are calculated. Equating the rate of energy dissipation to the external rate of work, the expression of support pressure is derived. With the help of variational approach, a performance function is proposed to reliability analysis. Improved response surface method is used to calculate the Hasofer-Lind reliability index and the failure probability. In order to assess the validity of the present results, Monte-Carlo simulation is performed to examine the correctness. Sensitivity analysis is used to estimate the influence of different variables on reliability index. Among random variables, the unit weight significantly affects the reliability index. It is found that the greater coefficient of variation of variables lead to the higher failure probability. On the basis of the discussions, the reliability-based design is achieved to calculate the required tunnel support pressure under different situations when the target reliability index is obtained.

• Journal of People, Plants, and Environment
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• v.24 no.3
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• pp.285-300
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• 2021

Background and objective: Rural migrants are an important human resource in urban and rural exchange (URE) business, therefore it is necessary to enhance their awareness and intent-to-participate. This study was to analyze the rural migrants' recognition and intent-to-participate of URE business and to propose the enhancement of them both. Methods: The questionnaire was designed to analyze the socio-demographic background, motivations, satisfaction with settlement, intent-to-persist, and intent-to-participate of URE business including tourism. The data of 144 respondents was subject to the statistical analysis. Results: The motives of migration were to enjoy leisure life after retirement, increased tiredness of city life, health problems, etc. The satisfaction with settlement was 3.67 at 5-point Likert scale. The intent-to-recommend and intent-to-publicize were 3.40 and 3.46, respectively. The intent-to-participate was 3.45, which was affected by the necessity of URE business and the support of central/local governments, and also showed a significant correlation with the satisfaction with settlement, intent-to-recommend, intent-to-publicize, tourism resources for green tourism or rural tourism, driving a car in Namhae county, and the service and price of meals. They thought the missions that the Namhae county office must focus on were to establish an internal/external public relations systems, establish a support system of central/local governments, and foster/support local leaders. Conclusion: It is necessary to improve the satisfaction with settlement and intent-to-persist, expand exchanges with local people, improve internal/external public relations systems, foster/support leaders, improve transportation in the county, enhance the service and price of meals, and develop/operate URE programs including tourism.

• Geomechanics and Engineering
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• v.31 no.1
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• pp.15-30
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• 2022

Slope stability during the excavation of twin road tunnels is considered crucial in terms of safety. In this research, physical model testing and numerical analysis were used to investigate the characteristics of the settlement (uz) and vertical stresses (σz) along the two tunnel sections. First, two model tests for a (fill-rock) slope were conducted to study the settlement and stresses in presence and absence of slope support (plate support system). The law and value of the result were then validated by using a numerical model (FEM) based on the physical model. In addition, a finite element model with a slope supported by piles (equivalent to the plate) was used for comparison purposes. In the physical model, several rows of plates have been added to demonstrate the capacity of these plates to sustain the slope by comparing excavating twin tunnels in supported and unsupported slope, the results show that this support was effective in the upper part of the slope, while in the middle and lower part the support was limited. Additionally, the plates appear to induce less settlement in several areas of the slope with differing settlement and stress distribution as compared to piles. Furthermore, as a results of the previous mentioned investigation, there are many factors influence the stress and settlement distribution, such as the slope's cover depth, movement during excavation, buried structures such as the tunnel lining, plates or piles, and the interaction between all of these components.

• The Journal of the Korea Contents Association
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• v.12 no.2
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• pp.310-321
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• 2012

This study was conducted to establish collaborative governance for North Korean Refugees' settlement support service. Three major actors were identified. At the central government level, there is no control center to coordinate various functions. This study suggested three roles for central government in collborative governance, which are policy planning based on public value, allocating financial resources to implementing organizations, and program evaluation for securing public accountability. The rloes of local government are establishing communication channels between implementing participants, maintenancing good relations, and coordination. Finally, the role of private actors is developing high quality service programs, connecting local resources for settlement service.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.101-113
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• 2018

This study aims to elucidate the major issues and problems of the North Korean woman defectors focusing on the Community settlement system of Korean society in the time of the historical change of the rapidly changing inter - Korean relations starting from the recent summit talks between North and South Korea. Analytical methods were conducted using literature and previous research data. The results of this study are summarized as follows. The necessity of legal and institutional support reflecting the characteristics of life of North Korean woman defectors and experience of defecting, the necessity of development and management of employment education and employment support program for stable settlement support, the necessity of an integrated support system of public - private cooperation governance structure The need for a tailored social adaptation program tailored to individual needs arises. The results of this study are important to suggest the direction of improvement of the actual system through studying the policy and system of the settlement of Korean society in advance of the unification era. In future research, the support system for the settlement of the South Korean society A variety of studies to identify the factors for role formation will be needed.

• Geomechanics and Engineering
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• v.32 no.3
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• pp.271-291
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• 2023

Settlement estimation in cohesion materials is a crucial topic to tackle because of the complexity of the cohesion soil texture, which could be solved roughly by substituted solutions. The goal of this research was to implement recently developed machine learning features as effective methods to predict settlement (S_m) of shallow foundations over cohesion soil properties. These models include hybridized support vector regression (SVR), random forests (RF), and coot optimization algorithm (COM), and black widow optimization algorithm (BWOA). The results indicate that all created systems accurately simulated the S_m, with an R² of better than 0.979 and 0.9765 for the train and test data phases, respectively. This indicates extraordinary efficiency and a good correlation between the experimental and simulated S_m. The model's results outperformed those of ANFIS - PSO, and COM - RF findings were much outstanding to those of the literature. By analyzing established designs utilizing different analysis aspects, such as various error criteria, Taylor diagrams, uncertainty analyses, and error distribution, it was feasible to arrive at the final result that the recommended COM - RF was the outperformed approach in the forecasting process of S_m of shallow foundation, while other techniques were also reliable.

• Journal of architectural history
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• v.17 no.5
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• pp.7-22
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• 2008

The purpose of this study is to examine the function of wall posts in pit-houses in the Bronze Age, in the Kyung-nam Province. Wall posts were found as post-holes, created after wooden posts had decayed. In this research, the role of wall posts is newly defined from the perspective of a construction engineering. While existing studies in archaeology regard wall posts as sub-posts that support the roof of a pit-house, this study views wall posts as piles installed to support the soil wall, not as sub-posts. Based on the existing reports on excavation in prehistoric settlement sites by archaeologists, the study examines the remnants of the wall posts and remains after a fire. The main findings of this study are threefold. First, the wall posts were installed not as posts but as piles, cut sharply and hammered along the building lines of a pit-house. Second, wall piles were used to support the walls during earthwork, such as excavating and banking for low ground, mostly because a large amount of soil is often lost during the process. Third, wall piles were used as post piles of retaining walls that enabled the installation of transverse wall panels, which were used to prevent the soil loss.

• Journal of the Korean Society of Safety
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• v.15 no.2
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• pp.97-102
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• 2000

This paper presents the design, construction and performance of ground treatment to support road embankment on refuse landfill. Long-term settlement of refuse landfill is analysised by Sower and Yen/scanlon. As a results of site test, predicting settlement excess the allowable settlement and ultimate bearing capacity is not satisfied. The effectiveness of DDR(Deep Dynamic Replacement) is monitered by field tests (SPT, PBT, PMT) before, during and after construction of the stone columns. The ultimate bearing capacity for reinforced landfill by stone columns obtained from the in-situ test results has been compared with the existing theories. In municipal wastes landfill, settlement after treatment using stone column is satisfied to allowable residual settlement. Therefore, long-term stability can be gain in these cases.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.317-326
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• 2018

The purpose of this study is to develop an AHP model to evaluate the relative importance and priorities of multi-cultural policies under bounded Rationality. The results of the study are as follows. First, in the evaluation elements for each measurement area, the following are the stable social settlement support policy (1rank), social capability development policy of multi-cultural family second generation (2rank), socio-economic activity policy (3rank), collaborative governance policy enforcement(4rank). Second, the priority of the measurement element is as follows. social settlement service target expansion policy was proved to be the top priority project stable social settlement support policy aspect and social capacity development policies of the second generation of multi-cultural families, social support policy was most important evaluated. Active economic activity support policy was as the top priority project socio-economic activity policy, and construct cooperation system of policy practice main agents was proved to be the top priority collaborative governance policy enforcement. These results will contribute to explain the reality of multi-cultural policy.