• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.105-114
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• 2004

Consolidation characteristics have been investigated by using Rowe cell consolidation tester for dredged soil, which is more than two times as much as the liquid limit. To examine the effects of variation of water content on consolidation characteristic, tests were carried out varying the initial water content from $100\%\;to\;150\%.$ The results were compared with the consolidation characteristics of remolded clay. The test results showed that the hither the initial water content of dredged clay was, the more noticeable the non-linear behavior of e-log P curves occurred. The variation of the gradient was apparent to load stage 40kPa and became less apparent after load stage 80kPa on the e-log P curves. Ratio of compression index stayed within the range suggested by Mesri and variation of initial water content has hardly influenced the coefficient of consolidation. On the contrary, it was found that the magnitude of consolidation load affects the vertical coefficient of consolidation. The variation of stratum thickness during consolidation processing needs to be taken into consideration since hydraulic fill would go through a much larger scale strain than land soil when it is subject to a load. In this study, the consolidation period considering the variation of stratum thickness was analyzed and the results were compared with those of existing consolidation studies which did not consider the variation of stratum thickness. According to the results of the study, the consolidation period of the ground with a larger strain was calculated more close to observed value in case of Mikasa theory which takes the variation of stratum thickness into consideration.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.343-350
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• 2020

In this paper, we present the results of research on the reconstruction of ancient routes of ancient civilization exchange that were once present in the North Jeolla region, which was undertaken by adopting a convergent approach to develop 'Silkroadpia', which is an online platform for the curation and sharing of archaeological and historical spatial data, and 'MEPTA(Multiple Evidence Based Path and Territory Finding Algorithm)'. The results of the research make it possible to reconsider the region's historical identity and its important role in facilitating cultural exchange on the Korean Peninsula and in East Asia. The results can also be used to provide the theoretical basis for the government's land planning policies and for the production of cultural contents that can be used for local regeneration. The ancient route associated with the Baekje Restoration Movement, that took place after the fall of Sabi in 660 CE, was the case study examined in this paper, which discusses the academic value of reconstructing the ancient route, as well as its future use in providing cultural contents.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.3
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• pp.13-22
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• 2012

The spatial structure analysis using the existing space syntax has a weakness only to apply the road factor. Hence, it is necessary to perform a new spatial structure analysis considering the regional characteristics factor as well as the road factor. The purpose of this study is to propose a modified spatial structure analysis which adopts road and regional characteristics factors using the existing space syntax and GIS and then to apply it to the spatial structure analysis of the urbanized areas in Hapdeok town. For the new analysis, the experts' survey has been conducted to derive the spatial structure factors of the area and their relative weights. Specifically, it drew the road factor as well as the regional characteristics factors such as road, district, land value, and building density. This study shows that the existing spatial structure analysis considering only the road factor does not reflect the actual spatial structure but the modified spatial structure analysis considering the road factor and the regional characteristics factors more accurately analyzes the spatial structure of Hapdeok town. Hapdeok is not an area where road networks were developed along main development axis and its centrality was changed, but an area where road networks were developed by effectiveness and equity and its centrality was changed by downtown decline. The towns like Hapdeok is more suitable for applying the modified spatial structure analysis method considering the regional characteristics factors. Further research is required for selecting characteristics factors and appropriate parameters in the modified spatial structure analysis. Further case studies await in other cities for conducting its verification.

• Journal of Cadastre & Land InformatiX
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• v.50 no.1
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• pp.181-200
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• 2020

This study used the OLS model to estimate the determinants affecting the tenure of a home and then compared the predictive power of each model with SVM, Decision Tree, Random Forest, Gradient Boosting, XGBooest and LightGBM. There is a difference from the preceding study in that the Stacking model, one of the ensemble models, can be used as a base model to establish a more predictable model to identify the volume of housing transactions in the housing market. OLS analysis showed that sales profits, housing prices, the number of household members, and the type of residential housing (detached housing, apartments) affected the period of housing ownership, and compared the predictability of the machine learning model with RMSE, the results showed that the machine learning model had higher predictability. Afterwards, the predictive power was compared by applying each machine learning after rebuilding the data with the influencing variables, and the analysis showed the best predictive power of Random Forest. In addition, the most predictable Random Forest, Decision Tree, Gradient Boosting, and XGBooost models were applied as individual models, and the Stacking model was constructed using Linear, Ridge, and Lasso models as meta models. As a result of the analysis, the RMSE value in the Ridge model was the lowest at 0.5181, thus building the highest predictive model.

• Journal of the Korean Geographical Society
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• v.50 no.6
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• pp.607-619
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• 2015

It is important to detect trails accurately for finding a proper management. We examined the applicability of KOMPSAT imagery to detect trails and found that it could be an efficient alternative to track trails correctly. We selected K2 and K3 imagery with different spatial resolution. Then, we processed each imagery to get NDVI, SAVI, and SC data. And then, we identified trails by object-based analysis and network analysis. Finally, we evaluated the potential trails with F-measurement and Jaccard coefficient which are based on correctness and completeness. The results show that the applicability is quite different in each case. Among them, especially the SC data with K3 shows the most highest value; correctness of detecting legal trails is 0.44 and completeness of that is 0.54. F-measurement and Jaccard coefficient are 0.49 and 0.32. In general, although there is a limit in detecting trails by using only KOMPSAT imagery, the usefulness of KOMPSAT imagery can be a higher considering its cost efficiency and availability of acquiring periodic data.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.1
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• pp.60-67
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• 2010

For sustainable use of the resources of uninhabited islands of Korea, their ecological economic potential needs to be fully integrated into their management policy and the carrying capacity of the islands should be evaluated before using or developing them. The emergy methodology was used to evaluate the ecological economic value and carrying capacity of Sungap-do which is an uninhabited island in Incheon, Korea. The system boundary for the emergy evaluation of the island included the sea area within 1km from the high tide level, following the management boundary for the uninhabited islands of Korea stipulated in the Law on the Conservation and Management of Uninhabited Islands. The total renewable emergy input to Sungap-do was $1.04{\times}10^{20}$ sej/yr from tidal energy. The annual ecological economic contribution of the island was evaluated high at 29.9 billion Em￦/yr. If Sungap-do were developed to the national average, its carrying capacity was 6,586 persons at the current living standard of Korea. The carrying capacity of Sungap-do for the long-term sustainability scenario was 2,337 persons at the same living standard as in the developed scenario. When only emergy contribution of the land area was considered, the carrying capacity of Sungap-do sharply decreased to 14 persons for the developed scenario and 5 persons for the long-term sustainability scenario. The carrying capacity of the uninhabited islands of Korea including Sungap-do, thus, needs to be considered from the initial stage of utilization or development projects to sustain the ecosystem benefits and their sustainable uses.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.79-94
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• 1985

This study was carried out to give basic information about the environmental conservation in Masan District. It included the actual vegetation the degree of human disturbance of vegetation, plant biomass and biomass production. The natural vegetation was nonexistent and the major plant communities of the secondary forest was P. thunbergii-Q. acutissima and Quercus forest. P. thunbergii-Q. acutissima community area was 29.2% of Masan District and the secondary forest and the afforestation area was 48% and 13% of Masan District respectively. The ecological diversity of the plant community was high value in Q. acutissima- P. thunbergii, Q.aliena and Carpinus laxiflora-Q.variabilis communicty. As the investigation of the ecological succession in Masan Forest, P. thunbergii community is edaphic climax and mixed forest will be changed gradually dominant species of Quercus species. It was implied that Genus Quercus hadnever beenso easily taken ever by the Genus Pinus which forms the edaphic climax at vast areas of forest land. In the degree of human disturbance of vegetation, the degree 7 (secondary forest 1) was 52.8% and the green spaces in Masan cover 65%, which nongreen spaces 35 %. Total amount of plant biomass produced from Masan District was estimated to be 160, 470.95 tons. Annual Production of dry matter biomass amounts to be 32,940.64 tons. Estimated amount for O$_2$produced annually from the vegetated area in Masan was 34,856 tons.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.6
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• pp.89-100
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• 2014

The Campus Core is centered at the physical, functional and symbolic environment of a university, which is known as the top academic institution, hence it metaphorically represents not only the educational philosophy when institution first opened, but also the transformed values of the time. Today, universities are asked to actively communicate with the local community in terms of function and be remodeled as pedestrian-friendly campuses in terms of physical environment. For this reason, the study comprehends the concept of the campus core in accordance with a pedestrian-friendly environment and suggests a practical plan for campus cores of district national universities based on previous research examination. Since the purpose of the study is to suggest a change in the circulation system centered on vehicle use to transform into a pedestrian-friendly environment through a planned approach while introducing public mixed-use at the same time, the study supports the fact that it is possible to reorganize the strategy of a pedestrian-friendly circulation system and partially revise the land utilization to yield the expected outcomes. Thus, this study will provide valid suggestions for similar maintenance plans while looking back to the meaning and value of today's campus core.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4514-4523
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• 2013

Currently the number of unsold housing is rapid increasing over again in the Seoul Metropolitan area. So this research analyzed effective and possible solutions focus on the potential customers and professionals. There was a research method setting up alternative solutions from the existing researches and the other suggestions though FGI (Focus Group Interview) by professionals. And then it investigated the efficient ways to resolve those problems through Conjoint Analysis. According to the result of this paper, firstly the customers considered 'financial supports', 'self-rescue efforts for construction companies' and 'taxation support' than the other. On the other hand, professionals evaluated 'publicly purchased housing' and 'new housing policies' were more essential solutions besides, both of them recognized the importance of ;financial support'. Secondly there were some ideas that it was necessary to more less control LTV (Loan to Value ratio) and DIT ( Debt to Income) and the LH (Korea Land and Housing Corporation) buy unsold housing. Finally the government and housing association had to manage and intervene the supply of housing within metropolitan area and restrict to building new properties and the construction companies actively provide less strict standard terms and conditions in contract for purchasing housing for instance, the decline of housing sale price or interest-free and so on.

• Journal of Korea Water Resources Association
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• v.53 no.8
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• pp.617-626
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• 2020

This study investigates changes of bifurcation discharge ratio, flow velocity distributions and characteristics of separation zone due to variation of bifurcation angle by using TELEMAC-2D model. When the bifurcation angle is reduced from 90° to 45° without changing the boundary conditions, the bifurcation discharge ratio increased by 1.5 times from 0.523 to 0.785 because of increasing the radius of curvatures, the inertia force of the downstream flow, and the pressure gradient by the downstream boundary conditions. The bifurcation discharge ratio increases non-linearly whenever the bifurcation angle decreases by 15° intervals from 90° to 45° in flow with the upstream Froude number of 0.45 to 0.74. In flow with a maximum Froude number of 0.74, the rate of increase for bifurcation discharge ratio is 31.1% and the minimum value. When the Froude number is 0.58, the bifurcation discharge ratio is 0.7 or less, and the maximum rate of increase for that ratio is 53.5%. As the upstream Froude number decreases less than 0.58, the bifurcation discharge ratio exceeds 0.7, and the rate of increase decreases. When the upstream Froude number is 0.4 higher, the dimensionless width and length changing ratio of the separation zone are about 2.56 and 5.5 times higher than in 0.4 or less.