• The Journal of Engineering Geology
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• v.29 no.3
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• pp.265-277
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• 2019

Changes in the amount, intensity, frequency, and type of precipitation, in conjunction with global warming and climate change, critically impact groundwater recharge and associated groundwater level fluctuations. Monthly gravity levels by the Gravity Recovery and Climate Experiment (GRACE) are acquired to monitor total water storage changes at regional and global scales. However, there are inherent difficulties in quantitatively relating the GRACE observations to groundwater level data due to the difficulties in spatially representing groundwater levels. Here three local interpolation methods (kriging, inverse distance weighted, and natural neighbor) were implemented to estimate the areal distribution of groundwater recharge changes in South Korea during the 2002-2016 period. The interpolated monthly groundwater recharge changes are compared with the GRACE-derived groundwater storage changes. There is a weak decrease in the groundwater recharge changes over time in both the GRACE observations and groundwater measurements, with the rate of groundwater recharge change exhibiting mean and median values of -0.01 and -0.02 cm/month, respectively.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.291-303
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• 2021

In the modern society, the number of people in disaster vulnerable groups is rapidly increasing such as the elderly, the disabled, foreigners, and children. The common characteristics of the groups vulnerable to disasters are that they live in residence types that are exposed to disasters because they are impoverished and if they are exposed to disasters, recovery is a slow process. The purpose of this study is to identify the new risk issues by performing risk issue analysis on the targets of disaster vulnerable group and provide base data for the development of the policies. For the research method, this study centered on the cases of children and pregnant women out of the disaster vulnerable groups and focused on the issue data of social media throughout the past 10 years ('10~'19) and performed social network analysis. As a result, first, the development of the issue showed relevance in the occurrence of specific cases. Second, the awareness about the types, targets, and management method of crisis management was analyzed. Third, an analysis was performed on the sentiment words that considered the solution measures of risk issues or the characteristics of the targets and it was analyzed that there were word that triggered negative emotions. Therefore, it is anticipated for the base data to be used for the government and also for the local government to build an effective crisis management system of the rapidly changing disaster environment on the basis of the sentiment analysis performed on the people of the nation as well as public awareness.

• The Korean Journal of Gastroenterology
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• v.72 no.6
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• pp.308-312
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• 2018

Percutaneous endoscopic gastrostomy (PEG) is widely used to provide nutritional support for patients with dysphagia and/or disturbed consciousness preventing oral ingestion, and PEG tube placement is a relatively safe and convenient non-surgical procedure performed under local anesthesia. However, the prevention of PEG-insertion-related complications is important. A 64-year-old man with recurrent pneumonia underwent tracheostomy and nasogastric tube placement for nutritional support and opted for PEG tube insertion for long-term nutrition. However, during the insertion procedure, needle puncture had to be attempted twice before successful PEG tube placement was achieved, and a day after the procedure his hemoglobin had fallen and he developed hypotension. Abdominal computed tomography revealed injury to a pancreatic branch of the superior mesenteric artery (SMA) associated with bleeding, hemoperitoneum, and pancreatitis. Transarterial embolization was performed using a microcatheter to treat hemorrhage from the injured branch of the SMA, and the acute pancreatitis was treated using antibiotics and supportive care. The patient was discharged after an uneventful recovery. Clinicians should be mindful of possible pancreatic injury and bleeding after PEG tube insertion. Possible complications, such as visceral injuries or bleeding, should be considered in patients requiring multiple puncture attempts during a PEG procedure.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.498-506
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• 2018

The purpose of this study is to examine the restorative effect of Semisulcospira libertina extract, on damaged liver cells induced by D-galactosamine in rats. Treatment of damaged liver cells with S. libertina extract significantly reduced local fatty degeneration, and inflammatory cell necrosis, to levels similar with the undamaged control group. In addition, S. libertina extracts were found to reduce plasma levels of liver damage indicator enzymes, such as AST, ALT, LDH and ALP, to control levels. It also reduced lipid peroxides, and lipid contents within damaged liver tissues. This suggests that S. libertina extract has a restorative effect on liver cells, thus reducing release of damage-associated liver enzymes, and oxidative degradation of lipids. Also, S. libertina extracts were found to be involved in recovery of damaged cells from inflammatory response by suppressing expression of $TNF-{\alpha}$, which leads to tissue injury and necrosis, whereas inducing expression of HO-1 that protects cells during inflammation. Thus, S. libertina extract restores liver tissue from necrosis and fibrosis, as well modulates expression of inflammation-related genes against liver damage. Our findings suggest that S. libertina extract is an effective medicinal resource, for improving and recovering liver cells from hepatic injury.

• Journal of Ecology and Environment
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• v.45 no.3
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• pp.105-116
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• 2021

Background: The creation of the National Institute of Ecology began as a national alternative project to preserve mudflats instead of constructing the industrial complexes by reclamation, and achieve regional development. On the other hand, at the national level, the research institute for ecology was needed to cope with the worsening conditions for maintaining biodiversity due to accelerated climate change such as global warming and increased demand for development. In order to meet these needs, the National Institute of Ecology has the following objectives: (1) carries out studies for ecosystem change due to climate change and biodiversity conservation, (2) performs ecological education to the public through exhibition of various ecosystem models, and (3) promotes regional development through the ecological industry. Furthermore, to achieve these objectives, the National Institute of Ecology thoroughly followed the basic principles of ecology, especially restoration ecology, in the process of its construction. We introduce the principles and cases of ecological restoration applied in the process. Results: We minimized the impact on the ecosystem in order to harmonize with the surrounding environment in all the processes of construction. We pursued passive restoration following the principle of ecological restoration as a process of assisting the recovery of an ecosystem degraded for all the space except in land where artificial facilities were introduced. Reference information was applied thoroughly in the process of active restoration to create biome around the world, Korean peninsula forests, and wetland ecosystems. In order to realize true restoration, we pursued the ecological restoration in a landscape level as the follows. We moved the local road 6 and high-voltage power lines to underground to ensure ecological connectivity within the National Institute of Ecology campus. To enhance ecological diversity, we introduced perch poles and islands as well as floating leaved, emerged, wetland, and riparian plants in wetlands and mantle communities around the forests of the Korean Peninsula in the terrestrial ecosystem. Furthermore, in order to make the public aware of the importance of the intact nature, the low-lying landscape elements, which have disappeared due to excessive land use in most areas of Korea, was created by imitating demilitarized zone (DMZ) landscape that has these landscape elements. Conclusions: The National Institute of Ecology was created in an eco-friendly way by thoroughly reflecting the principles of ecology to suit its status and thus the impact on the existing ecosystem was minimized. This concept was also designed to be reflected in the process of operation. The results have become real, and a result of analysis on carbon budget analysis is approaching the carbon neutrality.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.2
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• pp.73-80
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• 2011

The study reviewed the content and the meaning of the present Yeoju Palkyung(eight scenery) through analyzing and interpreting the Palkyung poems, old maps and paintings, and classic materials transmitted in Yeoju area, and investigated the landscape structure of the area around the Cheongshimru(淸心樓: pavilion). On the other hand, many Palkyung poems and Noojeongjeyong(樓亭) poems illustrating the Cheongshimru as the view point or the objective have clarified the scenic excellence when the Cheongshimru is the view point. The Yeoju Palkyung viewed from the Cheongshimru was described as constructing all around allocation structure, and six scenes are categorized as a distant view of the visual influence while the 7th scene Ireungdogyeon and the 8th scene Pasagwau are a psychologically influencing landscapes. The panoramic composition of the Yeoju Palkyung at the Cheongshimru is interpreted as the Seunggyeong distribution considering Palchaejigyeongsaek(八采之景色), where main viewpoint is the Cheongshimru and the distant landscape is Paldaejangrim. The reputation of the Cheongshimru, the central place of the Yeoju Palkyung, is confirmed by the technique of scene processing describing a various way of illustrating landscapes such as near view, distant view, pulling view and collecting view. The restoration of Cheongshimru and Paldaesup(八大藪) currently undertaken is the essential business for the full recovery of the Yeoju Palkyung, which will be not only for physical restoration but also for the shortcut to revitalize the history and the spirit of Yeoju. Furthermore, the business direction should be reconsidered to truly understand the meaning, the value, and the structure of the Yeoju Palkyung to ensure the pursuit of the sustainability aiming at the project "Local attractions", one of the Namhangnag Four rivers project of the ministry of Land, Transport and Maritime Affairs.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.3
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• pp.283-292
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• 2022

For fixed prosthetic treatment using implants, implants must be placed in a suitable location for prosthetic treatment. During surgery, minimally invasive prosthetic restoration is possible using a flapless method using a surgical guide. The patient in this case was an 86-year-old male patient who wanted treatment due to discomfort when using conventional dentures. Due to systemic disease, the patient had difficulty using removable local dentures, so full dentures for the maxilla and fixed implants for the mandible were restored. Because there is a high risk of bleeding due to systemic disease, the implant was placed in a flapless method using a surgical guide. Finally, prostheses were fabricated with maxillary full denture and mandibular screw-retained zirconia, and this report shows satisfactory esthetic and functional recovery.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.629-637
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• 2022

It is at risk of depletion of biodiversity due to indiscriminate overfishing of ecosystems and destruction of habitats. Intensive fertilizers or development of related facilities to increase agricultural production in poor indigenous areas devastate the soil. Preservation of biodiversity is now emerging as an important issue of global human coexistence. After the Post-2020 GBF Declaration, all governance in agricultural development in indigenous agricultural areas should be supported and promoted as biodiversity conservation measures. A compromise plan to reduce ecosystem development and biodiversity loss can help establish public governance policies. In this paper, a viability kernel used for viable control feedback analysis is introduced to solve conflicting economic and ecological problems in ecosystem conservation, and a mathematical model on biodiversity conservation by the viability kernel is examined. Because all species in the ecosystem are interdependent, if the balance is broken, biodiversity is depleted, which is irreversible and eventually leads to extinction. For sustainable use and harmony of biological resources, a lot of policy consideration is required, such as creative governance that can efficiently protect all species. Subsidies or tax incentives have a direct impact on biodiversity conservation. The recovery of species in a state of decreasing biodiversity can be said to be of great economic value. Biodiversity will allow indigenous producers to be proud of their unique traditional knowledge and have a positive impact on local tourism, thereby enhancing regional identity and greatly contributing to the survival and prosperity of mankind.

• Wind and Structures
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• v.35 no.1
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• pp.1-20
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• 2022

This research work presents an experimental study's outcomes to reveal the impact of an O-ring on the flow control over a sphere placed in a turbulent boundary layer. The investigation is performed quantitatively and qualitatively using particle image velocimetry (PIV) and dye visualization. The sphere model having a diamater of 42.5 mm is located in a turbulent boundary layer flow over a smooth plate for gap ratios of 0≤G/D≤1.5 at Reynolds number of 5 × 10³. Flow characteristics, including patterns of instantaneous vorticity, streaklines, time-averaged streamlines, velocity vectors, velocity fluctuations, Reynolds stress correlations, and turbulence kinetic energy (), are compared and discussed for a naked sphere and spheres having O-rings. The boundary layer velocity gradient and proximity of the sphere to the flat plate profoundly influence the flow dynamics. At proximity ratios of G/D=0.1 and 0.25, a wall jet is formed between lower side of the sphere and flat plate, and velocity fluctuations increase in regions close to the wall. At G/D=0.25, the jet flow also induces local flow separations on the flat plate. At higher proximity ratios, the velocity gradient of the boundary layer causes asymmetries in the mean flow characteristics and turbulence values in the wake region. It is observed that the O-ring with various placement angles (𝜃) on the sphere has a considerable alteration in the flow structure and turbulence statistics on the wake. At lower placement angles, where the O-ring is closer to the forward stagnation point of the sphere, the flow control performance of the O-ring is limited; however, its impact on the flow separation becomes pronounced as it is moved away from the forward stagnation point. At G/D=1.50 for O-ring diameters of 4.7 (2 mm) and 7 (3 mm) percent of the sphere diameter, the -ring exhibits remarkable flow control at 𝜃=50° and 𝜃=55° before laminar flow separation occurrence on the sphere surface, respectively. This conclusion is yielded from narrowed wakes and reductions in turbulence statistics compared to the naked sphere model. The O-ring with a diameter of 3 mm and placement angle of 50° exhibits the most effective flow control. It decreases, in sequence, streamwise velocity fluctuations and length of wake recovery region by 45% and 40%, respectively, which can be evaluated as source of decrement in drag force.

• Journal of the Korean Geographical Society
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• v.29 no.1
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• pp.16-38
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• 1994

The spatial structure of Korea has been changed drastically during the second half of this century. The events such as the Korean War and the resultant division of the Korean Peninsular into two Koreas, rapid industrialization and urbanization are the major causes among others for the spatial changes of the nation. The changes in turn have spawned a number of spatial problems. It is time, we argue, to diagnose how much the nation is now ill-structured, and to discuss of which directions the long-term spatial management be reoriented. A delphi survey was conducted during the early 1993 to fulfill such research needs. Questionnaires were distributed among geographers, planners, and high governmental officials throughout the nation. These 'experts of spatial problems' were requested to evaluate the past spatial policies and strategies, and to identify spatial and environmental problems at the national, regional and local levels. The survey included questions with regard to the spatial problems in North Korea too. A complementary literature survey in the fields of spatial sciences was accomplished as well in order to identify the major research interests and issues with regard to the nations's spatial structure. The delphi survey results indicatee that the present spatial structure: in relation to consumption, housing and economic activities is satisfactory in overall, while rather poor in terms of education, leisure and community activities. Most of the experts consider infrastructural improvements are urgent in the areas of roads, waste disposal facilitles, railroads, harbors, water supply and drainage systems. The over-concentration of economic, social and political function in the Seoul Metropolitan Region is perceived to be the most serious spatial problem in Korea. The long-term solutions suggested are strategies toward a more balanced regional development as well as toward a cleaner environment. The concensus among the experts for the short-term solution is the redistribution of population and industries from the Seoul Metropolitan Region to the intermediate and small cities. The land use policies and concurrent large-scale infrastructural projects are evaluated largely pertinent and desirable in general. It is, however, suggested that development projects be conducted in a more harmonious way with environment. The survey respondents suggest that the present environmental management policies should be reexamined critically. With regard to regional and local problems, transportation and pollutions are thought to be most serious in the Seoul Metropolitan Region, while employment opportunities, and information, education and health care services are most deprived in small cities and rural areas. The majority of the experts consider a city size of 250, 000-500, 000 population is desirable to live within. Respondents beileve that North Korea's physical environment is still not aggravated much whereas its infrastructural provisions are largely pool. The co-authors of this research figure a "environmentaly sound and spatially balanced Korean Penninsular" as the ideal type of spatial structure in Korea. The basic guidelines toward this ideal prototype are suggested: the recovery of spetial integrity, progressive restructuring of the nation, land uses geared to public welfare rather than private interests, and eco-humanistic approach in spatial policies.