• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.2
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• pp.33-42
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• 1993

In order to obtain the basic information for the optimal settlement planning in the reclaimed area, various existing settlement conditions on reclaimed farming village were analysed through a case study of in-and-round farming villages in Deuk Ryang Reclaimed Area. By comparison study between in-and-around villages, the allocation policy of farming settlement in the samll and medium scale area was proposed. The results obtained in this study were as follows ; 1.The population structure of the inner village(Ansim village) had become worse than the around village during 1976~1981 period from the viewpoint of total and female emigration ratios. Especially, the originally unbalanced sex ratio of Ansim village had worsen to the unacceptable ratio of 1.5 : 1(male : female). Therefore, the structural stability of the population should be carefully improved in the newly reclaimed farming villages by the systematic long-term controlling machanism.2.The farming status of Ansim village was much lower than the around villages viewing of the cultivated acreage and agricultural machinery stock Therefore, the continuous and intensive governmental support different from the existing farming area should be required for the settling of reclaimed farming. 3. The regularity of the village site as a planned village, though pursed in the first phase of village construction, had been severely disturbed inflowing of squatters. Recently, there are increasing vaccant houses in the village, and the level of living amenities and personal mobility of Ansim village are much lower than the around village. So, now, the physical structure of the village should be improved to the level of village reconstruction or new village construction. 4. The cultivated area of Ansim village leans to the south side which would be unfavoured by the farmers of the around villages, while its distributing pattern should be concentric around the village site. This phenomenon disturbs the central fuction of the planned farming village. In this respect, role assignment, relationship and balance of competence in farming activities should be planned between in-and-around villages in the reclaimed area from the initial stage. 5. Putting together the above results in this study, the farming and living conditions of Ansim village threaten its existence as a planned new farming village in the reclaimed area. And, so, the full scale reconstruction of village structure, including moving to the new site, should be designed as soon as possible. Although further many studies should be carried out, it would be sure that the new village planning should be reconsidered in the small and-medium scale reclamation works.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.1
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• pp.49-64
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• 2014

Seabed beneath and near the coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If the liquefaction occurs in the seabed, the structure may sink, overturn, and eventually fail. Especially, the seabed liquefaction behavior beneath a gravity-based structure under wave loading should be evaluated and considered for design purpose. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using 2-dimensional numerical wave tank. The 2-dimensional numerical wave tank was expanded to account for irregular wave fields, and to calculate the dynamic wave pressure and water particle velocity acting on the seabed and the surface boundary of the structure. The simulation results of the wave pressure and the shear stress induced by water particle velocity were used as inputs to a FLIP(Finite element analysis LIquefaction Program). Then, the FLIP evaluated the time and spatial variations in excess pore water pressure, effective stress and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the analysis, when the shear stress was considered, the liquefaction at the seabed in front of the structure was identified. Since the liquefied seabed particles have no resistance force, scour can possibly occur on the seabed. Therefore, the strength decrease of the seabed at the front of the structure due to high wave loading for the longer period of time such as a storm can increase the structural motion and consequently influence the stability of the structure.

• The Journal of Engineering Geology
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• v.7 no.3
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• pp.191-205
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• 1997

Measurements on subsurface movement of the Songsanri tomb site including the Muryong royal tomb was conducted using a tiltmeter system for the period of 15 months form July 7, 1996 to September 30, 1997. Two coordinate tilt monitoring data shows the biggest movement rate of 2.3mm/m/yr toward south in the frontal wall(N-S tilt) of the Muryong royal tomb. Southward tilting of bricks above the southern fire place in the western wall of the Muryong royal tomb is a proof of southward tilting of the royal tomb since its excavation in 1971. The eastern wall of the Muryong royal tomb is also tilting toward inside the tomb with the rate of 1.523mm/m/yr. Furthermore, tilting rate of wall increases twice in rainy season. It is interpreted tbat infiltration of water into the tomb and nearby ground in rainy season results in dangerous status for the safety of tomb structure. On the whole, normal component tilting of the walls of the 5th tomb is large than its shear component. It shows a small displacement toward one direction without no abrupt change in its direction and amount of tilting. The tilting rate of walls of the 6th tomb is about 8.8mm/m/yr in the dry season which is much bigger than those of other tombs in rainy season. Deformation events of walls of the tombs are closely related to amount of precipitation and variation of temperature. In comparison with different weather conditions, tilting is much bigger during the period of rainy weather than sunny weather. It is interpreted that rainwater flew into the turm through faults and nearby ground. High water content in nearby ground resulted strength of ground. The tilting event of walls shows a hysterisis phenomenon in analysis of temperature effect on tilting event. The walls tilt rapidly with steep rising of temperature, but the tilted walls do not come back to original position with temperature falling. Therefore, a factor of steep increase of the temperature must be removed. It means the tomb have to be kept with constant temperature. The observation of groundwater level using three boreholes located in construction site and original ground represented that groundwater level in construction site is higher than that of original ground during the rainy season from the end of June to August. It means that the drainage system of the Muryong royal tomb is worse than original ground, and it is interpreted that the poor drainage system is related to safety of tomb structure. As above mentioned, it is interpreted that artificial changes of the tomb environment since the excavation, infiltration of rainwater and groundwater into the tomb site and poor drainage system had resulted in dangerous situation for the tomb structure. According to the result of the long period observation for the tomb site, it is interpreted that protection of the tomb site from high water content should be carried out at first, and the rise of temperature by means of the dehumidifier inside the tomb must be removed.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.2
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• pp.1-13
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• 2009

In this paper, we develop theoretical game models to determine the level of government subsidies for banks to provide policy loans to Innovative SMEs(small and medium sized enterprises) through banks, which otherwise would not finance them for the sake of their own profitability. For this, we compare net cash flows of each bank using different strategies against high risk innovative SMEs. A bank can decide whether to provide them loans or not In each period. Following Kim(2003)'s Infinite horizon model on the soft budget constraint, we introduce a situation in which banks compete against each other for higher net long-term payoffs from their loans to innovative SMEs and non-innovative SMEs. From the models, we show that competition among banks in general leads to a tighter decision against innovative SMEs, as a Nash equilibrium. It is not because the government bank is simply loose in providing loans, but because competition among commercial banks for fewer riskier borrowers results in tighter loan decisions against innovative SMEs. Thus, the competitive market for policy loans to innovative SMEs fails to reach the socially optimal level of loans for innovative SMMs. Commercial banks in the competitive market may require additional supports from the government to make up for the differences in their payoffs to support innovative SMEs, possibly much riskier due to moral hazards and poor discounted cash flows. The monopolistic government bank might also request such supports from the government to fund otherwise unqualified SMEs. We calculate an optimal level of governmental support for banks to guarantee funding such high-risk innovative SMEs over periods without deviating from their optimal Nash equilibrium policies.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.65-73
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• 2011

Recently, researches to introduce the performance warranty contract are in progress for quality improvement of road pavements. The performance warranty contract is a type of contract in which contractors guarantee to maintain certain level of performance during a period from completion of construction. The contract use in Europe and the U.S is being increased because it has been known to contribute to improvement of structure quality, reduction of life cycle cost, development of construction techniques, and etc. The research on performance indicators, threshold values, and warranty durations is essential to effectively introduce the contract in Korea. In this study, literatures on the performance warranty contract for concrete pavements of the Minnesota, Indiana, and Florida of the U.S. were reviewed. Major distresses influencing the pavement performance were investigated and analyzed in the jointed concrete pavement sections of 21 Korean expressway routes to be compared to the performance indicators, threshold values, and warranty durations of the states. More accurate comparison is expected by investigation in planned sections for a long time.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.186-195
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• 2005

Topography of beach line is keeping stability for several years, their soil values have been maintained in balances. Install of coastal structures have caused deformation for beaches and acted as a function to structures. Therefore, quantitative prediction of beaches topography according to structure install is required to prevent the beaches deformation and progress proper coastal preservation work. In this study, we analyzed coastal changes caused by erosion and accretion according to development and drew up a cross-section to share 8 stations using coordinates and depth surveying in groin of Soheuksan island port. Elevation distribution and changes by observation period is calculated -0.30m~+0.20m after comparing results of five months in October 7, 2004 surveying results and fell into insignificance. We thinks periodic observation of coastal erosion and accretion take place for the season and long-term coastal changes in beaches width is analyzed.

• Journal of Ecology and Environment
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• v.41 no.4
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• pp.125-131
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• 2017

The ground beetles collected during the investigation period were nine subfamilies, 24 genera, 51 species, and 3504 ground beetles. Species richness was high in Pterostichinae has 24 species (47%), Harpalinae nine species (17.6%), Carabinae six species (11.8%), and Lebiinae three species (5.9%). Overall dominant species was Synuchus agonus, and dominance index was 0.361. Synuchus agonus was investigated as the dominant species in both Namcheon Valley and Geumseon Valley. Regarding subdominant species, it was Synuchus nitidus (52 individuals, 12.6%) and Synuchus cycloderus (52 individuals, 12.6%) in the order in Namcheon Valley, and it was Pterostichus orientalis orientalis (660 individuals, 21.3%) and Pterostichus audax (378 individuals, 12.2%) in the order in Geumseon Valley. Total species diversity index of ground beetles in Sobaeksan National Park was 2.917. By area, the number of collected ground beetles was smaller in Namcheon Valley than in Geumseon Valley. Sobaeksan National Park is located at the boundary of northern and southern parts in Korea and is a very important place in terms of geography and climate. Sobaeksan has been designated as a national park, and its ecosystem is relatively preserved well. If continuous investigation of basic data for ground beetles is conducted through long-term monitoring, the data can be used as key data to research mutual relationship with organisms, effects by climate change, and ecosystem change depending on human activities.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.84-97
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• 1983

Under the limited arable land, the enhancement of agricultural productivity is indispensable to provide the food demand which is concomitant with the rapid increase in population. From this viewpoint, the upbringing and dissemination of high-yielding varieties has been promoted continuously and several modifications in cultural practices, including heavy fertilization, dense planting, and early transplanting, also have been gradually developed. However these changes in cultivation have led to the increased outbreak of insect pests and diseases. And this unexpected results have accelerated the number and complexity of pesticides employed as well as their consumption. Even though pesticides are essential materials contributing to the steady production of agricultural crops, large scale consumption of them has given rise to several adverse impacts, such as mammalian hazard and/or environmental contamination. In this respect, recent development of new pesticides has been concentrated on 'safe pesticide', as it were, that has the highly selective properties without unfavorable side influences on other ecosystem. According to literature cited up to now, feasibilities of safe pesticide development would be summarized as two categories. One of them is the development of chemical pesticides, which include the molecular structure modification of established pesticides for increased safety and synthesis of new safe chemicals which can attack the vulnerable point of physio-ecological characteristics in insect pests and diseases. The other is the biological pesticides which comprise natural enemies and microorganisms to act selectively on confined insect pests and diseases, In addition, improvement of physico-chemical properties of available pesticide formulations would be one of the desirable means for safe pesticide development in view of efficacy enhancement and minimization of hazardous properties or safe pesticide development, various approaches are feasible and needed to study, however, long period and much financial outlay are necessary to develop a new item. And under the present situation in Korea, there are many difficulties for performing research on all the possible routes. Therefore, combined pesticides by the reasonable combination of already registered resticides evaluated as the fairly safe pesticides and safe formulation based on their physico-chemical properties would be developed primarily. And many efforts would be given gradually for the development of new chemical and biological pesticides.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.74-81
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• 2008

Urban Regeneration has an object to restore a function of urban through physical/cicumstance, social lift/culture, industrial/economic regeneration. It has characteristics like existence of a lot of projects, complextity of stakeholders' structure, long period of project life cycle to achieve variety of project's promotion strategy. To accomplish a Urban regeneration that has above characteristics successfully, information about other projects should be managed organically. And it should provie information linked up with each projects by integrated management. We need a decision making method that helps users cope with requirements of change during project, and offers information when each users need to make a decision timely. So I propose a strategy to build the IETM considering urban regeneration characteristics.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.89-104
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• 2011

This study was carried out to the development of ecological planting model to make up of coastal windbreak forest on the Suncheon-bay in Sucheon-si, Korea. Make up of coastal windbreak forest in this site was needed for appropriate bioresource, biodiversity and ecological structure, and for conservation of the eco-tour resource and protection of human life and property by the unforeseen disaster from the coast. Based on the plant-social principle, the planting model of windbreak forest was developed to facilitate growth of trees, considering planting locations. The ecological planting model for the coastal windbreak was composed of warm temperate evergreen and windbreak forest which is spreading around the inland area in Korea. The horizontal forest style was composed of forest edge community and inner forest community, and the vertical forest style was composed of upper, middle, low and ground planting class. The target of the present model was quasi-natural forest, and the species of tree were selected based on the adaptability to surroundings depending on a goal to create a forest and forest style. To achieve both functions of wind break forest and visual effect in short period of time, small trees and seedlings were planted with high-density of 40,000/ha in an expectation of easy natural maintenance in the future. The significance of the present study is a suggestion for a guideline to create ecological coastal windbreak forest in the Suncheon-bay in which the harmony of human life and the ecological conservation is of great importance. Also, the ecological coastal windbreak forest model should be developed further through the long term monitoring after construction of forest.