• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.463-467
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• 2004

Rosette-type diffusers with four-ports per riser are constructed in relatively shallow water in Korea. However, the trajectorial bending phenomena due to lower-pressure inside the surrounded buoyant jets on the riser was not considered in most models and was not observed without any experimental results. The buoyant jet behavior affected by the bending effect where there have been growing interests need to be verified experimentally and need to be preceded in the analysis of the characteristics of the buoyant jets oil a riser. The hydraulic model experiments have been carried out to investigate the characteristics of the behavior of horizontal buoyant jets discharged from a Rosette-type riser with four ports as well as single port over a certain range of the experimental conditions including initial momentum and initial buoyancy using LIF (Laser Induced Fluorescence) system to obtain concentration fields. The intensity of the fluorescent light in each pixel on the images obtained from LIF system with the tracer of Rhodamine H was converted to the local dye concentration with a set of calibration procedures to account for the non-uniform distribution of light intensity and the attenuation of light energy by water medium. The experimental results shows that the trajectories from Your ports tend to bend more and more to the inner side with the increase of the densimetric Froude number while the buoyant jet from a single port rises up without any bending phenomena. The previous models, VISJET and Seo et al. (2002), do not simulate the trajectories well except the region before the bending section. This study will focus on the analysis of the behavior of the buoyant jets for mainly a Rosette-type riser by conducting hydraulic model experiments using LIF system.

• 한국지반환경공학회 논문집
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• 제14권3호
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• pp.5-11
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• 2013

본 연구는 홍수 시 교량하부에서 발생되는 세굴에 의한 문제점을 조사하기 위한 연구로서 실제 현장에서 실험에 의하여 규명이 쉽지 않은 세굴과 관련된 교량하부구조 거동에 대한 해석적 연구이다. 본 연구에서 제시된 해석모델의 경우 도로교 시방규정에서 제시한 표준하부구조 단면을 기준으로 세굴에 따른 3축 지반지지력 표현 및 손실이 가능하도록 유한요소 모델링을 수행하였고 상용유한요소해석 프로그램인 ANSYS를 이용하여 해석을 수행하였다. 고려된 하중조건으로는 시간에 따른 유량변화를 단계적으로 고려하였으며 다양한 형태의 세굴조건과 지반지지력 변화에 대하여 교량하부구조 거동을 조사하였다. 최종적으로 교량하부구조의 거동은 세굴발생 면적 및 형태에 따라서 다양한 결과들을 보여주었으며, 이들 결과들은 향후 교량하부구조 세굴보호공 설계기준 마련을 위한 기초자료로 유용하게 활용될 수 있을 것이다.

• 한국전산구조공학회논문집
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• 제31권2호
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• pp.105-114
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• 2018

본 연구에서 페리다이나믹 이론 모델을 이용하여 준정적하중과 동적 하중, 균열전파와 분기균열 패턴 그리고 등방성재료, 직교 이방성 재료의 균열 진전 해석 등 다양한 조건을 고려한 전산 시뮬레이션을 수행하여 그 적합성을 검토하였다. 초기 균열은 없지만 중심에 홀이 있는 등방성 재료, 초기 균열이 존재하는 등방성 및 이방성 재료에 대한 전산 시뮬레이션이 수행되었다. 조정 동적 완화 기법이 사용되어 준정적 하중을 모사하였고, 이방성 재료 해석에서는 고전 연속체 역학과 페리다이나믹의 변형률 에너지를 고려한 균질화 방법이 사용되었다. 균열 전파와 분기 균열이 성공적으로 확인되었으며 파괴 거동의 시작과 그 방향 역시 페리다이나믹 이론으로 확인되었다. 페리다이나믹을 균질화 방법을 사용하여 비교적 복잡한 이방성 재료에 적용한 경우 역시 실험 결과 값과 비교하여 검증하였다.

• 한국방재학회 논문집
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• 제7권3호
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• pp.51-58
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• 2007

본 연구에서는 강원 지역에 거주하는 대학(원)생과 비거주하는 대학(원)생 750명을 대상으로 강원 지역의 재난특성, 방재의식 수준 등에 대한 조사를 수행하였다. 분석결과, 응답자 모두 강원 지역의 재난발생 가능성(74.0%)이 가장 높은 것으로 인식하는 것으로 나타났다. 강원도 거주자 군은 비거주자 군에 비해 풍수해와 산불 피해의 발생가능성이 높다고 인식하고 있는 것으로 나타났다. 강원도 지역에 재난이 많이 발생하는 원인은 불리한 자연조건, 방재시설의 부족, 지역주민의 방재의식 부족을 그 요인으로 인식하고 있는 것으로 조사되었다. 강원도 지역의 방재의식을 고취하기 위한 방법으로는 방재관련 시설의 확충과 방재관련 교육을 중요하게 인식하는 것으로 나타났다. 특히, 재난교육에 대한 경험이 없는 응답자가 전체의 62.1%로 조사되어 재난교육의 확대가 필요함을 알 수 있다.

• 한국시뮬레이션학회논문지
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• 제20권1호
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• pp.97-105
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• 2011

하천에서, 생물막은 녹갈색의 얇은 막의 형태로 돌, 식물, 그리고 기타 구조물의 표면에 부착되어 있다. 생물막은 주로 영양물의 순환, 수질정화, 바닥 침전물 제거, 그리고 먹이사슬내의 에너지 흐름에 매우 중요한 역할을 한다. 본 연구에서, 우리는 유체 흐름 안에서, 독소-생산 종과 독소-민감 종의 복합적 생물막을 전산 모사하는 모델을 개발하였다. 유체 흐름으로는 균일한 흐름과 불 균일한 흐름 두 가지를 고려하였다. 균일한 흐름은 확률 프로세스로 구현되었으며, 불 균일한 흐름은 나비어-스톡스 방정식으로 구현되었다. 모델에서, 독소-생산종과 독소-민감종 간의 상호작용을 고려하기 위해, 종 개체의 번식률과 사망률이 고려되어졌다. 우리는 서로 다른 두 유체 흐름 내에서 전산 모사 되어진 생물막의 구조적 형상에 대해서 간략히 논의 하였다.

• Structural Engineering and Mechanics
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• 제52권3호
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• pp.613-632
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• 2014

In the early design stage of ships, the two most important structural analyses are performed to identify the structural capacity and safety. The first step is called global strength analysis (longitudinal strength analysis or hull girder strength analysis) and the second step is local buckling analysis (stiffened panel strength analysis). This paper deals with the ultimate strength performance of Arctic Sea Route-going commercial ships considering the effect of low temperature. In this study, two types of structural analyses are performed in Arctic sea conditions. Three types of ship namely oil tanker, bulk carrier and container ship with four different sizes (in total 12 vessels) are tested in four low temperatures (-20, -40, -60 and $-800^{\circ}C$), which are based on the Arctic environment and room temperature ($20^{\circ}C$). The ultimate strength performance is analysed with ALPS/HULL progressive hull collapse analysis code for ship hulls, then ALPS/ULSAP supersize finite element method for stiffened panels. The obtained results are summarised in terms of temperature, vessel type, vessel size, loading type and other effects. The important insights and outcomes are documented.

• Molecules and Cells
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• 제40권7호
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• pp.450-456
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• 2017

Mammalian physiology and behavior are regulated by an internal time-keeping system, referred to as circadian rhythm. The circadian timing system has a hierarchical organization composed of the master clock in the suprachiasmatic nucleus (SCN) and local clocks in extra-SCN brain regions and peripheral organs. The circadian clock molecular mechanism involves a network of transcription-translation feedback loops. In addition to the clinical association between circadian rhythm disruption and mood disorders, recent studies have suggested a molecular link between mood regulation and circadian rhythm. Specifically, genetic deletion of the circadian nuclear receptor Rev-$erb{\alpha}$ induces mania-like behavior caused by increased midbrain dopaminergic (DAergic) tone at dusk. The association between circadian rhythm and emotion-related behaviors can be applied to pathological conditions, including neurodegenerative diseases. In Parkinson's disease (PD), DAergic neurons in the substantia nigra pars compacta progressively degenerate leading to motor dysfunction. Patients with PD also exhibit non-motor symptoms, including sleep disorder and neuropsychiatric disorders. Thus, it is important to understand the mechanisms that link the molecular circadian clock and brain machinery in the regulation of emotional behaviors and related midbrain DAergic neuronal circuits in healthy and pathological states. This review summarizes the current literature regarding the association between circadian rhythm and mood regulation from a chronobiological perspective, and may provide insight into therapeutic approaches to target psychiatric symptoms in neurodegenerative diseases involving circadian rhythm dysfunction.

• 대한약침학회지
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• 제18권2호
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• pp.76-85
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• 2015

Objectives: Radix Ginseng has been traditionally used as an adaptogen that acts on the adrenal cortex and stimulates or relaxes the nervous system to restore emotional and physical balance and to improve well-being in cases of degenerative disease and/or old age. Radix Ginseng has been used for a long time, but the safety of ginseng pharmacopuncture needs testing. This study was done to analyze the single-dose toxicity of water- soluble ginseng pharmacopuncture (GP) intramuscular injections in rats. Methods: All experiments were performed at Biotoxtech, an institution authorized to perform non clinical studies under the regulations of Good Laboratory Practice (GLP). Each group contained 10 Sprague-Dawley rats, 5 males and 5 females. GP was prepared in a sterile room at the Korean Pharmacopuncture Institute under regulations of Good Manufacturing Practice (GMP). GP dosages were 0.1, 0.5 and 1.0 mL for the experimental groups; normal saline was administered to the control group. The animals general condition was examined daily for 14 days, and the rats were weighed on the starting day and at 3, 7 and 14 days after administration of the pharmacopuncture. Hematological and biochemistry tests and autopsies were done to test the toxicological effect of GP after 14 days. This study was performed with approval from the Institutional Animal Ethics Committee of Biotextech. Results: No deaths were found in this single-dose toxicity test of intramuscular injections of GP, and no significant changes in the general conditions, body weights, hematological and biochemistry tests, and autopsies were observed. The local injection site showed no changes. Based on these results, the lethal dose was assumed to be over 1.0 mL/animal in both sexes. Conclusion: These results suggest that GP is relatively safe. Further studies, including a repeated toxicity test, are needed to provide more concrete evidence for the safety of GP.

• International Journal of Computer Science & Network Security
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• 제21권12호
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• pp.316-322
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• 2021

The problem of corruption and the spread of corruption crime today is not only one of the main social problems, but also an obstacle to the implementation of reforms in Ukraine. Given the complexity, scale and diversity of the impact of corruption, it is an undisputed threat to national security. At the state level, corruption threatens, firstly, state security as a result of its spread in public authorities and the combination of political and business spheres; secondly, in the domestic political sphere as a result of non-compliance and violation by officials of public authorities and local governments of the laws of Ukraine; thirdly, in the economic sphere as a result of the dominance of personal interests of civil servants over national ones; fourthly, in other spheres, namely, military, social, ecological, informational, foreign policy, etc. The origins of corruption are diverse and are formed not only in the country but also abroad. The current corruption threat is the result of the country's ineffective domestic and foreign anticorruption policies. Acceleration of the spread and manifestation of external corruption threats is associated with a number of unresolved foreign policy issues against the background of the development of globalization and integration processes, in particular: economic and financial dependence of the country on international financial institutions and organizations; as well as from foreign countries that pose a potential threat due to their ambitious plans to expand our country; unresolved issues regarding the international legal consolidation of borders, etc. It is noted that the current conditions for the development of state security, due to new challenges and threats, need to improve and implement new measures to prevent corruption as a negative impact of the main threats to national economic security. As a result of the study, the main measures to counter the main threats to the economic security of the state were identified.

• 농촌계획
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• 제29권3호
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• pp.53-67
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• 2023

In this study, the problem of the idleness of public buildings in rural areas is seriously emerging, but there are no clear standards for assessing the utilization of these buildings. Therefore, this study endeavors to investigate the actual state of idleness of buildings created by rural area development projects based on the criteria for each type. As part of this study, rural facilities were selected in two locations in Sangju City and Miryang City among the target areas of the Rural Agreement. Utilization evaluation criteria were developed to identify the conditions of underutilization. In order to determine the utilization pattern for each facility type, an in-depth interview with the operator and an inspection of the facility were conducted. Based on the analysis, the degree of utilization (e.g., low use, non-use, etc.) was different for each facility type, and among the four facility types (rural tourism, culture and welfare, exercise and recreation, income-based), rural tourism was rated as the least efficient. It has been found that the operating entity's capacity has a significant influence on the utilization of facilities. Socioeconomic factors, such as a decrease in utilization rates, are greatly influenced by the operating entity's capacity. Therefore, support from local governments as well as the national level is required to recycle idle facilities. Lastly, this study suggests the need for different standards for utilization, depending on the type of facility. This moves beyond checking the degree of idleness by the same standard that was previously implemented.