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      • 공동주택 지하주차장 평면형태 및 환기구의 배치에 따른 공기유동에 관한 연구

        박성원 부산대학교 2010 국내석사

        RANK : 247805

        The study on the airflow based on the array of ventilator and plan of the underground parking lot in apartment As demands of the residents have been variously changing according to the construction of the apartment house and the fast economic growth, the construction companies spurs the development of the apartment house flavored with environmental friendly factors. Also because of the multiple apartment project, the basement car park alone can not handle the rapid growth of the vehicles and the resident puts more and more emphasis on securing car park space for the freedom from the vehicles on the ground and for the safety of their children. Recently, as the interest about natural energy, the tendency minimizing the mechanical energy also appears. According to this trend, there has been growing attempts in order to apply the environmental friendly technologies to the apartment house. But the reality is that the systems doesn't virtually function well because the existing mechanical systems are applied. Consequently, the deterioration of the air and the brightness in the basement car park exacerbates the environments of the basement car park. And the study on the feasibility of the natural ventilation according to the unit-plan type of the basement car park and the performance of the skylight, is still insignificant. Thus, in this study, we intend to simulate, through the CFD, the air current by natural driving power by classifying the existing basement car parks into the unit-plan type and the direction of the vehicle traffic. Through classifying the existing basement car parks by the type of vehicle traffic that is the type of arrangement such as one-way or bidirectional traffic and deploying the ventilating openings by 3 types which enables the skylights, linked the ground for the purpose of collecting the light, play the role of ventilation at the same time, we forecast the air current of the basement car park by using CFD(Computational Fluids Dynamics) and, based on that, suggest the plan to improve the ventilating function of the basement car park by utilizing the natural ventilation. In this study, we research the general theories, that is 'the ventilation theory of underground space and the test method of ventilating performance' and interpret, through CFD, the air current of the target models according to the layout of the ventilation openings based on mean of air age and air exchange effectiveness by using computer simulation. As a result, we draw the conclusion as follows: (1) In respect of the air age according to the type of the vehicle traffic such as one way traffic and bidirectional traffic, the bidirectional traffic shows 30,405 seconds while 14,070 seconds in one way traffic indicating that the one way traffic abates by more than 50%. Therefore, the air of the basement car park with one way traffic has superior air quality because of its' shorter air age. (2) In case of the existing basement car parks, Case A' air exchange rate is 4.44 while 7.76 times/h in Case B and 1.94 times/h in Case C. It appears comparatively small in Case C. We can draw the conclusion, through this finding, that the placement of several natural ventilators in the middle and on the edge is more effective than the placement of the natural ventilator with big area in the middle when placing natural ventilator. (3) In case of Case B where the installation is in the middle and on the edge of the basement car park, it appears excellent in both the air exchange and the air age, but the effective area of the space on the ground abates. There requires a plan for the placement accordingly. (4) In case of Case C where the circular air-vent with the smallest area of air-vent is installed, the velocity of air current appears the fastest. Thus, it seems that there requires the research on the appropriate size and the layout plan of the circular air-vents for the purpose of the increase of effective space on the ground. It is also necessary to comprehend the appropriate locations in order to improve the performance of the natural ventilation, through examining the characteristic of the air current according to the type of ventilating openings installed in the basement car park, the velocity of the current, the pressure distribution and the installation of the auxiliary equipments for the natural ventilation.

      • Genetic analysis of PARK2 gene in Korean patients with Parkinson's disease

        박인원 忠南大學校 新藥專門大學院 2016 국내박사

        RANK : 247805

        Mutations in PARK2 are considered a common cause of Parkinson’s disease (PD). To assess the frequency of PARK2 mutations in the Korean population, we screened the PARK2 gene in 83 Korean PD patients: two young onset (YO, ≤49), 32 middle onset (MO, 50-69) and 49 late onset (LO, 70). Detection of the point mutations was performed by direct sequencing of the PARK2 exons, and exonic rearrangements were analyzed using multiplex ligation-dependent probe amplification (MLPA). Five known PARK2 variants were identified in 53 (63.9%) of the Korean PD patients: two missense mutations (Y267H and M458L) and three polymorphisms (S167N, L272I and V380L). We also found an increased frequency of PARK2 variants in PD patients and a lowered PD age at onset (AAO) in those having two variants, suggesting that the genetic variation in PARK2 gene might be a genetic risk factor of PD in Korean population.

      • How does the national park management deliver their services? The perspective of service marketing focused on gunung gede pangrango national park, Indonesia

        Maulana, Firman 서울시립대학교 국제도시과학대학원 2018 국내석사

        RANK : 247804

        인도네시아에 설립된 가장 오래된 국립공원 중 하나인 구눙 게대 빵랑오 국립공원(GGPNP)은 관광 개발의 기초로 생태관광을 선택했다. 생태관광과 관련된 모든 혜택에 관계 없이 미래에 최적의 이익을 얻으려면 여전히 해결해야 할 과제가 있다. 정부기관으로서 GGPNP는 방문객에게 서비스를 제공하는 관광 활동을 지원하는 단순한 관리 이상의 또 다른 역할을 한다. 최근의 사실은 국립공원에 방문하는 관광객 수가 여전히 적다는 것을 보여주며 그 이유 중 하나는 국립공원에서 마케팅에 대한 관심이 낮기 때문이다. 국립공원은 또한 성과 중 하나인 방문 관광객 수에 대한 목표를 달성해야 하지만 GGPNP의 경영진은 서비스 마케팅을 시행하여 국립공원을 홍보하는 방법에 주목하기 시작해야 한다. 이러한 이유로 본 연구는 서비스 마케팅 관점에서 GGPNP가 서비스를 제공하는 방법을 조사하기 위해 실시되었다. 또한 이 논문은 생태관광 원리를 강조하는 경영진 측면과 인지된 서비스 성과 차원을 강조하는 방문객 관점에서 서비스 마케팅의 3가지 요소(인력, 물리적 증거, 프로세스 관리)를 탐구한다. 조사 결과에 따르면 GGPNP의 서비스 마케팅 구현은 전반적으로 중간 수준이다. 이는 GGPNP가 이미 표준 서비스 마케팅을 수행하지만 마케팅 가치를 높이기 위해 해결하고 개선해야 할 몇 가지 사항이 있다는 것을 의미한다. 인적 요소의 경우 GGPNP는 방문객에게 더 나은 서비스를 제공하기 위해 더 많은 인력을 충원하고 더 많은 교육을 제공해야 한다. 물리적 증거 요소의 경우 방문객은 GGPNP가 국립공원 지역에 머무는 동안 방문객에게 더 많은 지식과 편의를 제공하기 위해 국립공원 지역에 정보 표지판과 위생 시설을 개선하거나 추가해야 한다고 생각한다. 마지막으로, 프로세스 관리 요소에서 GGPNP는 더 많은 절차를 추가하고 고객 평가, 방문 우선순위 시민에 대한 대우(노인, 임산부, 장애인, 어린이), 방문객에게 피드백을 제공하는 방식에 대해 구체적인 사항을 추가해야 한다. GGPNP의 경영진에게 이 결과가 의미하는 바는 특히 인도네시아에서 국립공원의 서비스 마케팅에 대해 논의하는 이전 연구가 없었기 때문에 공식적인 계획 전략을 위한 마케팅 참조자료와 디딤돌을 제공하는 것이다. 또한 훌륭한 서비스 마케팅을 시행함으로써 장기적으로 국립공원을 방문하여 보존 메시지를 받고 환경에 대한 소속감을 높일 수 있는 사람들이 더 많아질 것이다. Gunung Gede Pangrango National Park (GGPNP) one of the oldest national parks established in Indonesia has chosen ecotourism as the basis of their strategy in developing tourism. Regardless of all of the benefits that come with ecotourism, there are challenges that are still need to be addressed to gain optimum benefit in the future. As a government agency, GGPNP has another role than just mere conservation which is supporting tourism activities which mainly about delivering a service to its visitors. The recent data shows that the number of tourist arrival to the national park is still low, and one of the reasons is the low interest of marketing for a national park. While the national park also needs to achieve the target for tourist arrival as one of their performance, the management of GGPNP needs to start their attention on how to market the national park through the implementation of service marketing. Due to these reasons, this research was conducted to examine how the GGPNP delivers their services from the perspective of services marketing. In particularly, this thesis explores the three elements of services marketing (personnel, physical evidence, and process management) from the perspective of management which emphasizes ecotourism principles and the perspective of visitor which emphasizes on perceived service performance dimension. The results of this survey show that as overall the implementation of service marketing in GGPNP is at a moderate level. This means that GGPNP already perform standard service marketing but there are several things that need to be addressed and improved to increase their marketing value. From the personnel element, the GGPNP need to consider adding more personnel and provide them with more training in order to deliver better services to the visitor. For the physical evidence element, the result also shows that the visitor thinks that GGPNP needs to improve or add more information signage and sanitary facilities in the national park area to give more knowledge and comfortability toward visitor during their stay in the area of national park. Lastly, from the process management element shown that GGPNP need to add more procedure and put more specific details on customer evaluation, treatment for priority citizen (elderly, pregnant woman, disabled person, and children) that come to visit, and how they provide their feedback to the visitor. This research is expected to serve as a stepping stone and reference on marketing and planning strategies of GGPNP since there was no previous research that discusses service marketing in the national park especially in Indonesia. Furthermore, by implementing good services marketing it is expected that for long-term outcome there will be more people to visit a national park to receive the message of conservation and hence increase their sense of belonging toward the environment.

      • Spatio-Temporal Patterns of Human-wildlife Conflict in Bardia National Park, Nepal

        PAUDEL, Prabin University of Seoul, International School of Urban 2021 국내석사

        RANK : 247676

        지구 생태계의 균형을 이루기 위해서는 야생 생물 보존이 필수적이다. 하지만 야생 동물이 인간에게 피해를 입히면 인간은 그에 대한 복수로 야생 동물을 살상한다. 따라서 생태계 및 인간이 영위하는 생활의 지속 가능성을 위해서는 충돌을 최소화해야 한다. 인간과 야생 동물의 충돌은 바르디아 국립 공원(Bardia National Park)의 주요한 해결 과제이다. 효과적인 충돌 관리를 위해서는 구체적인 시공간 정보가 필수적이다. 그렇기 때문에, 본 연구에서는 바르디아 국립 공원의 완충 지대에서 11년(2010~2020) 동안 발생하여 기록된 충돌의 시공간적 분포를 조사하였다. 데이터 분석에는 기술 및 추론 통계를 사용하였다. 분석 결과에 따르면 기록된 충돌 횟수가 매년 증가하고 있다. 평균적으로 연간 806 건의 충돌이 기록되었다. 이 보호 구역에서 발생한 충돌의 주요 대상 종은 코끼리와 표범인데, 충돌의 59%가 남부 지역에서 기록되었다. 인간과 코끼리의 충돌 중 60% 이상이 8월, 9월, 10월 및 11월에 발생했다. 충돌이 가장 빈번한 계절은 종마다 다르지만, 코끼리, 표범, 호랑이 및 멧돼지의 경우 충돌의 계절적 분포가 유의미하다. 조사 대상 기간 동안의 손실 평가액 중 37%만이 보조금 형태로 지급되었다. 보조금을 받기까지의 과정도 길다. 따라서 지역을 바탕으로 주요 충돌 종을 관리하기 위한 월간 일정이 필수적이다. 초식 동물의 입맛에 덜 맞는 대체 작물을 재배하고 육식 동물의 침입을 막을 수 있는 축사를 장려하는 것이 필요하다. 전기 울타리를 설치하고 유지하며 대체 생계 수단을 제공함으로써 사람들의 삼림 출입을 줄이는 것 또한 중요하다. 이에 더해, 지역 사회를 대상으로 야생 동물의 행동에 대한 지식을 제공하고 교육을 실시하는 또한 바르디아 국립 공원 내에서의 충돌 사고를 축소하는 데 도움이 될 것이다. 주요어: 인간과 야생 동물의 충돌, 시공간 분포, 바르디아 국립 공권, 완충 지대 Human-wildlife conflict is one of the major conservation challenges. Detail spatial and temporal information is essential for effective conflict management. Therefore, this study examines the distribution of conflicts based on space and time for eleven years (2010 to 2020) in the buffer zone of Bardia National Park. Descriptive and inferential statistics were used to analyze the data. The result shows that the number of human-wildlife conflicts is increasing annually. Where on average, 806 conflicts per year were recorded. Elephant and leopard are the major conflicting species in this protected area, and 59 % of the conflict was recorded in the southern regions. More than sixty percent of human-elephant conflicts are recorded in August, September, October, and November. Major conflicting seasons vary with the species, where the distribution of conflict is significantly varied with the seasons for elephant, leopard, tiger, and wild boar. Attack due to carnivore is significantly higher in the new moon phase periods. Only 37 % of the evaluated loss was paid to the victim as a relief. A monthly calendar for the management of major conflicting species is essential. Farming of alternative crops that are less palatable for the herbivores and promoting predator-proof livestock shelter is needed. Where construction and maintenance of electric fences and reduction of dependency over forest resources by providing alternative sources of livelihood are crucial. Furthermore, providing knowledge and training about wildlife behavior to the local community will reduce the conflict and increase the harmony between people and wildlife.

      • First-Principles Characterization of Transition Metals on Oxide Films

        Park, Jinwoo University of Seoul 2010 해외박사

        RANK : 247663

        Oxide-supported metal clusters and thin films have attracted a great deal of interest due to their importance in a wide range of technological applications, such as heterogeneous catalysis, gas sensors, corrosion-protective coatings, photovoltaic devices, and microelectronics. The adsorption, growth, and electronic characteristics of metal atoms adsorbed on oxides are of special interest, because these factors are supposed to help design and optimize methods for controlling processes concerning the desired chemical reaction and product. In this thesis, we performed ab initio electronic structure calculations to study the interactions of metal adatoms with ionic oxide atoms involving regular oxide surface atoms, surface oxygen defects like Fs centers, and metal supports. As an oxide, an MgO(001) surface, a prototype of an ionic oxide surface, was chosen here. All calculations were carried out using the density functional theory (DFT). First, a systematic approach was employed to investigate the adsorption geometries and electronic structures of late transition series (Cu, Ag, Au, Ni, Pd, and Pt) on ideal defect-free MgO(001) surfaces. For the above elements, the adsorption geometries, diffusion, and associated electronic structures were examined. Our calculations showed the favorable adsorption of the transition metal (TM) adatoms on top of the surface O atom. Further analysis showed that the TM-induced states formed in the gap region of MgO(001) vary significantly with the adsorption geometries. The DFT calculations have been also applied to investigate the adsorption of the TM adatoms (Cu, Ag, Au, Ni, Pd, and Pt) on defective MgO(001) surfaces with Fs centers as surface defects of oxides. The TM adatoms were found to favorably bind on the Fs centers. From the calculated adsorption structures and electronic structures, we carried out a systematic comparative analysis of the interactions of the metal adatoms with the surface oxygen vacancy and the regular surface oxygen atom of MgO(001). Finally, the adsorption of metal adatoms (Au and Pd) on Fe-supported ultrathin MgO(001) films was studied. Experimentally, it is well known that MgO films are epitaxially grown on Fe(001) due to their favorable physical properties. As such, the Fe/MgO/Fe junctions have been used as a system for magnetic tunnel junctions (MTJs) with huge tunneling-magnetoresistance (TMR) values. Interestingly, our calculations showed that the MgO/Fe(001) films we propose in this work can be used as a viable thin oxide model system. An analysis of the electronic structures in the systems reveals the negative charging even for Pd adatoms with a lower electron affinity. This indicates that the Fe substrate supporting the MgO films significantly influences charge and/or spin states of the metal adatoms. The physical origin of the negative charging of Pd was also discussed. These calculations demonstrate the importance of the interactions of the metal adatoms with underlying oxides for controlling the electronic and chemical properties of metal adatoms, such as charge and spin states.

      • (An) orbit-based explainability method for graph neural networks

        Park, Kyeongrok Sungkyunkwan University 2023 국내석사

        RANK : 247647

        현존하는 GNN의 설명 방법론들은 설명 범위에 따라 모델 레벨과 인스턴스 레벨로 분류될 수 있다. 인스턴스 레벨의 설명은 GNN이 각 input data를 가지고 작업을 수행할 때 중요하게 본 노드, 엣지 또는 서브 그래프를 설명으로 제시한다. 이러한 설명은 GNN이 개별 데이터들을 분류할 때 어떠한 패턴을 중요하게 인식하였는지 파악하는데 도움을 준다. 모델 레벨의 설명은 GNN이 각각의 input data가 아닌 전체 데이터들을 특정 클래스로 분류할 때 중요하게 본 노드, 엣지 또는 서브 그래프를 설명으로 제시한다. 이러한 설명은 GNN이 데이터들을 분류할 때 사용한 보편적인 패턴을 분석하는 데 도움을 준다. 이렇듯 두가지 설명 모두 다른 관점에서의 GNN을 설명하는데 도움이 되기 때문에 중요하다. 그러나 두 가지 관점에서의 설명을 모두 제공하는 방법론은 존재하지 않는다. 이러한 한계점을 극복하기 위해 본 연구는 노드 분류 작업에 대해 인스턴스, 모델 레벨의 설명을 모두 제공하는 새로운 GNN 설명 방법론인 O-GNNExplainer를 제시한다. 우리의 방법론은 모티프 단위의 설명을 제공하기 위해 non-isomorphic subgraph들의 집합인 graphlet과 각 graphlet 내부의 구조적으로 구별되는 노드들인 orbit를 설명 단위로 사용한다. 또한 GNN을 embedding-model와 downstream-model로 분리하여 설명하고자한다. O-GNNExplainer는 우선 노드 representation vector들과 각 노드 별 orbit 존재 유무를 활용하여 orbit weight를 학습한다. 이후 downstream-model의 각 클래스 분류에 기여하는 weight를 orbit weight 단위로 분해하여 각 orbit의 기여도들을 모델 레벨의 설명으로 제공한다. 또한 각 노드들의 예측 결과를 orbit weight로 분해함으로써 instance 레벨의 설명 또한 제공할 수 있다. 우리는 synthetic-dataset에서 새롭게 제시한 task를 통해 O-GNNExplainer가 ground-truth motif를 모델 레벨의 설명으로 제시할 수 있는지 검증하였다. 또한 기존의 연구들에서 사용된 평가 기준들을 개선하여 다양한 real, synthetic dataset에서의 실험을 통해 O-GNNExplainer가 baseline method들 보다 높은 성능을 보여주는 것을 확인하였다. Graph Neural Networks (GNNs) have achieved state-of-the-art performance on a variety of tasks involving graph data. Due to these impressive performances, numerous studies on GNN explainability have emerged. Existing GNN explainability studies can be categorized into model-level and instance-level methods. Model-level methods provide subgraphs that contribute significantly to the overall behavior of GNNs with respect to specific class labels. In contrast, instance-level methods aim to identify important subgraphs within individual data instances. While both perspectives are invaluable for understanding the behavior of a model, it is more beneficial to offer explanations in a more human-interpretable unit within a unified framework. In this paper, we propose an explanation model, O-GNNExplainer, capable of decomposing the predictions of existing GNNs at both the model-level and instance-level, using the orbit as the unit of explanation. Notably, O-GNNExplainer can decompose the learning results of GNNs into 73 orbit units in predefined graphlets, demonstrating interpretable results in various domains, including biology and social network. In our experiments, O-GNNExplainer consistently outperformed existing baselines in generating explanations across six distinct datasets.

      • Modeling of electromagnetic force density in dielectric and magnetic materials using concepts of infinitesimal particles and external fields

        Park, Byungsu Sungkyunkwan university 2021 국내박사

        RANK : 247647

        When dielectric or magnetic objects are placed in an electromagnetic field, they can be moved and deformed by an electromagnetic force. If the objects are nondeformable solids, the net force is sufficient to predict the object motion. However, to predict their deformation, it is necessary to determine the force distribution on the objects. Various expressions and methods are used to calculate the electromagnetic body force on an object, and there are four notable forces: Lorentz, Kelvin, generalized, and Korteweg–Helmholtz force densities. However, each force distribution may differ significantly. We adopt the concepts of infinitesimal particles and external fields to address this issue. The adaptation of these concepts enables the electromagnetic force distribution inside the dielectric and magnetic objects to be uniquely determined. We refer to this type of force density as the local electromagnetic force density (F_LEM). This study primarily focuses on the derivation of F_LEM. The validity of F_LEM is demonstrated using simple numerical models. During this process, the local electromagnetic energy density is also introduced. 전자기장 내부에 유전체와 자성체는 전자기력에 의해 움직이고 변형된다. 물체의 운동을 예측하기 위해서는 물체에 작용하는 전자기합력을 아는 것으로 충분하다. 그러나 변형을 예측하기 위해서는 물체 내부의 각 부분에 작용하는 전자기력의 분포를 알아야 한다. 물체에 작용하는 전자기력을 계산하기 위해서 다양한 방법이 사용되고 있다. 그 중 가장 대표적인 네가지는 Lorentz, Kelvin, generalized, and Korteweg–Helmholtz force이다. 그러나 물체 내부에서 네 힘의 분포는 매우 다르다. 이러한 문제를 해결하기 위해 infinitesimal particles 개념과 external fields 개념을 도입한다. 위 개념들을 도입하면, 물체 내부의 전자기력 분포는 하나로 정해지며 이를 Local electromagnetic force density (F_LEM) 라고 한다. 본 논문에서는 앞서 언급한 개념들을 이용하여 F_LEM을 유도하고 수치해석 모델을 통해 F_LEM의 유효성을 보인다. 이 과정에서 기존의 전자기에너지 밀도의 무효성을 보인다.

      • Development of self-emulsifying nanoemulsion containing atorvastatin and ezetimibe

        Park, Shinae Sungkyunkwan University 2013 국내석사

        RANK : 247647

        The aim of this study was to develop complex Self-nanoemulsifying drug delivery system (SNEDDS) containing atorvastatin and ezetimibe. Atorvastatin, marketed as calcium salt form, is the top-selling drug and used to treat hyper cholesterolemia which could lead to severe disease like heart attack and stroke. In recent, ezetimibe is co-administered with atorvastatin. Because it has reduced adverse effect of statin drugs, and has been shown to provide significant incremental reductions with a synergy effect. These drugs are poorly water-soluble and have sufficient Log P values to be incorporate in lipid-based formulations. SNEDDS formulations are beneficial to solubilize atorvastatin and ezetimibe drug molecules. To solubilize the two kinds of drugs, excipients that could act as oil, surfactant or cosurfactant were screened. Three excipients of each oil, surfactant and cosurfactant groups were selected in the order of solubilizing capacity. Among the 33 nanoemulsion compositions, ‘Ethyl oleate-Tween 80-PEG 600’ was evaluated as best composition by pseudo ternary phase diagrams. To select most effective and stable SNEDDS formulations, the effect of oil contents on size and zeta-potential of droplets was examined. Moreover, there were techniques to solubilize more atorvastatin in optimal SNEDDS. The first was an elevation of pH value of SNEDDS environment, and the second was a conversion of drug salt formation. As a result, the second technique was successful in that atorvastatin free acid was 8 fold soluble than its calcium form in the system. The complex formulations containing atorvastatin calcium and free acid were compared each other. Also, the powders of atorvastatin calcium and its acid form were characterized by SEM/EDS, PXRD, DSC, and FT-IR. For two optimal complex formulations, size distribution, mean droplet size, zeta potential and morphology were assessed. Physical stability and dissolution profile of formulations was investigated to confirm advantages of this system. As a result, the physical stability in water and simulated gastric and intestinal fluid might come from extremely small droplet size and surface charge of droplets. The faster dissolution profile of the drugs from SNEDDS, especially in ezetimibe, establishes use of SNEDDS as a potential delivery system for water insoluble drugs.

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