도시캐노피 밑 난류특성매개변수화를 고려한 중규모 모델개발 및 이를 이용한 도시특성 모의

학위논문 (박사)-- 서울대학교 대학원 : 대기과학과, 2014. 2. 윤순창.This study is carried out to simulate the flow and turbulence in urban area for air pollution modeling using a modified urbanized mesoscale model. The Urban Canopy Parameterization (UCP) of Dupont et al. (2004) implemented in MM5v3.7 mesoscale meteorological modeling system (MM5-UCP-Basic) is evaluated against the non-urbanized model (MM5-NoUCP) using measurements taken in urban Phoenix during two field studies. In general, MM5-UCP-Basic improved the predictions of typical meteorological parameters. Nevertheless, significant discrepancies still exist between observations and the predictions of MM5-UCP-Basic, and new parameterizations and land use classes are introduced to improve the model performance. The parameterization of anthropogenic heat flux from buildings and roadways is also included. The land use classes in the improved model (MM5-UCP-MOD) represent roadways and rivers, in addition to five classes of buildings identified in MM5-UCP-Basic. New parameterizations considered the appropriate roughness length, velocity decay during evening transition, and heat and momentum diffusivities for the nocturnal period so that account for different heat and momentum transfer rates under stable atmospheric conditions. Five nested grid domains are used for simulations, with the highest resolution (1km) implemented into the MM5-NoUCP, MM5-UCP-Basic and MM5-UCP-MOD. Improved parameterizations were validated by detailed flow and turbulence measurements which were conducted as the Phoenix SUNRISE field experiment in 2001 (Lee et al., 2003Doran et al., 2003) and TRANSFLEX in 2006 (Fernando et al., 2013). This research was to refine the urban land use classification in MM5-UCP-Basic and modify the turbulence parameterizations to better represent surface fluxes and urban effect such as UHI and LLJs. The features of this modified model, MM5-UCP-MOD, are presented in this research together with its validation and comparisons with MM5-UCP-Basic and original MM5v3.7 (referred to as MM5-noUCP). According to sensitivity tests for parameterization improvement, the parameterization changing the turbulence length scale in TKE is the most significant to develop the high performance of momentum flux in urban simulation. In general, substantial improvements in the prediction of wind speed, temperature (especially during the nighttime) and momentum flux as well as a smaller improvement in the heat flux are noted, so that is pointing to possible further enhancement onto model performance by including the improved physics. By the way, the MM5-UCP-MOD is useful to understand the UHI and urban meteorology so as to simulate and predict the nocturnal air pollution in the city, especially. The temperature field and heat flux including effect of UHI in urban center are better simulated by MM5-UCP-MOD with urban data for Phoenix than by the standard version of MM5 (MM5-NoUCP). Besides, transient events of end of high mountainous area, which enclosed the downtown, are also accomplished to simulate by MM5-UCP-MOD. The transient events are typically developed by coupled effect of topographical condition of Phoenix and thermally driven flow in neighborhood scale. And it seems to be analyzed by drag force approach inside roughness sub-layer. The budgets of turbulent kinetic energy near the boundary from output of MM5-UCP-MOD are able to understand the turbulent energy transform near the top of building canopy. Since three-dimensional observations are not enough to verify the simulation and the use of urban and vegetation canopy morphology database with land use type are too simplified, validation of new parameterization is not enough. Nevertheless, the formation of LLJ owing to UHI and transient events with nocturnal downslope flow in transient time can be explained using MM5-UCP-MOD. And also, this effect produced the nocturnal high ozone concentrations and can be only simulated by MM5-UCP-MOD. Although the limitation of comparison with measurement for ozone and PM10, the analysis of the model outputs emphasized that results from MM5-UCP-MOD and CMAQ are useful to understand and predict the urban meteorology and air pollution.ABSTRACT i TABLE OF CONTENTS v LIST OF FIGURES vii LIST OF TABLES xiii 1. Introduction 1 1.1 Review of previous studies 1 1.1.1 Urbanized meso-scale meteorological model 1 1.1.2 Urban heat island (UHI) phenomena 6 1.2 Motivation and Objectives of research 8 2. Implementation of new Urban Canopy Parameterization 12 2.1 Introduction 12 2.2 Implementation of Urban Canopy Parameterization (UCP) in MM5 for Phoenix in MM5 18 3. Application and modification of turbulence parameterization in MM5-UCP-Basic 28 3.1 Setup and simulation condition in MM5 28 3.2 Comparison of simulations with surface observations 30 3.3 Modification of turbulence parameterizations in MM5-UCP -Basic 38 3.3.1 Brief description of turbulence parameterization in DA-SM2-U 38 3.3.2 Issues of original MM5-UCP-Basic and modifications 45 4. Validation and sensitivity of MM5-UCP-MOD 53 4.1 Comparison of simulations with surface observations 53 4.1.1 Field experiments 53 4.1.2 Numerical simulations 58 4.2 Sensitivity to each improvement 59 4.3 Simulation results of modified version, MM5-UCP-MOD 63 5. Application of MM5-UCP-MOD to Urban Effects simulations 72 5.1 Impacts of urban heat island effect 72 5.2 Urban effect on transient event 86 5.3 Effect on air pollution distribution 96 5.3.1 Air pollution modeling 96 5.3.2 Results of air pollution modeling 97 6. Summary and conclusion 105 REFERENCES 109 국문 초록 119Docto

The study on the Improvement Plan of the Customs Administration Managing Free Trade Zone

본 연구는 항만형 자유무역지역, 특히 부산항의 자유무역지역을 중심으로 자유무역지역이 현재 당면하고 있는 관세행정상의 문제점을 파악하고 이를 개선할 수 있는 방안을 제시하고자 한다. 이를 위해 보호무역이론과 자유무역이론을 검토하여 자유무역지역 도입의 이론적 배경에 대해 알아본다. 또한 자유무역지역과 유사한제도 즉 경제자유구역, 종합보세구역와 제도적인 측면에서 비교, 분석하고 특허보세구역과는 화물관리측면에서 비교 분석하여 자유무역지역의 특성에 대해 알아본다. 또한 자유무역지역 지정절차, 지정요건, 지정현황을 통해 현재 자유무역지역의 운영현황에 대해 알아본다. 이런 분석을 바탕으로 자유무역지역의 관세행정상의 몇 가지 문제점을 도출하였다. 이런 문제점에 대한 개선방안으로 첫째, 자유무역지역법상 복합물류사업범위를 넓게 해석하고 둘째, 업종코드 변경시 심사절차 완화, 셋째, 자유무역지역법의 벌칙규정을 관세법으로 일원화, 넷째, 최신화 된 자유무역지역 가이드 북을 제작하는 것을 제시하였다.The purpose of this study was to identify the problems currently faced by the customs administration in the free trade zone, particularly the free trade zone of Busan Port and to suggest ways to improve them. This thesis examined the theoretical background of the introduction of the free trade zone by analyzing the theory of protected trade and free trade. In addition, a system similar to that of the free trade zone, the Free Economic Zone, and the Comprehensive Bonded Zone, were compared and analyzed in terms of institutions. This thesis also compared it with the patent bonded area and analyzed it in terms of cargo management to investigate the characteristics of the free trade zone. This thesis investigated the current status of operations in the free trade zone through the procedures, requirements, and status of the free trade zone designation. Based on this analysis, several problems - vii - were discovered in regard to the customs administration in the free trade zone. The following ideas were suggested as an improvement plan for these problems. First, a broad interpretation of the scope of the complex logistics business was proposed in accordance with the laws of the free trade zone. Second, when the industry code is changed , it was suggested that the improvement policy to ease the screening process. Third, The penal provisions of the Free Trade Zone Act sould be merged with the Customs Act. Finally, This thesis suggested that a updated Free Trad Zone guide book should be produced.제1장 서 론 1 제1절 연구의 배경 및 목적 1 제2절 연구의 방법과 구성 2 제3절 선행연구분석 3 제2장 이론적 배경 9 제1절 자유무역이론 9 제2절 보호무역이론 13 1. 관세의 경제적 효과 13 2. 쿼터의 경제적 효과 16 제3장 자유무역지역의 특성과 현황 18 제1절 자유무역지역의 특성 18 1. 자유무역지역의 정의 18 2. 자유무역지역제도의 특징 20 3. 자유무역지역과 유사 제도 22 4. 자유무역지역의 화물관리 27 5. 보세구역의 화물관리 32 제2절 자유무역지역의 지정현황 40 1. 자유무역지역 지정절차 40 2. 자유무역지역 지정요건 41 3. 자유무역지역 지정현황 43 제4장 자유무역지역의 개선방안 44 제1절 자유무역지역의 문제점 44 1. 자유무역지역의 복합물류업의 한계 44 2. 업종코드변경시 심사 절차 복잡 46 3. 관세법과 비교시 과중한 처벌규정 49 4. 최신 자유무역지역 업무지첨서 부재 49 제4절 자유무역지역의 개선방안 50 1. 자유무역지역법 복합물류사업 범위를 폭넓게 해석 50 2. 업종코드 변경시 심사 절차 완화 50 3. 자유무역지역법의 벌칙규정을 관세법으로 일원화 51 4. 자유무역지역 신가이드 북 제작 51 제5장 결론 53 참고문헌 55Maste

Association Between 5-HTTLPR Polymorphism and Tics after Treatment with Methylphenidate in Korean Children with Attention-Deficit/Hyperactivity Disorder.

OBJECTIVES: The purpose of this study is to examine the relationship between 5-HTTLPR polymorphism (44-bp insertion/deletion polymorphism of serotonin transporter gene) and methylphenidate (MPH) treatment response, as well as the association between the adverse events of MPH treatment and 5-HTTLPR polymorphism in children with attention-deficit/hyperactivity disorder (ADHD). METHODS: A total of 114 children with ADHD (mean age 9.08 ± 1.94 years) were recruited from the child psychiatric clinic in a hospital in South Korea. We have extracted the genomic DNA of the subjects from their blood lymphocytes and analyzed 5-HTTLPR polymorphism of the SLC6A4 gene. All children were treated with MPH for 8 weeks, with clinicians monitoring both the improvement of ADHD symptoms and the side effects. We compared the response to MPH treatment and adverse events among those with the genotype of 5-HRRLPR polymorphism. RESULTS: There was no significant association between the 5-HTTLPR genotype and the response to MPH treatment in children with ADHD. Subjects with the S/L+L/L genotype tended to have tics and nail biting (respectively, p < 0.001, p = 0.017). CONCLUSIONS: The results of this study do not support the association between the 5-HTTLPR polymorphism and treatment response with MPH in ADHD. However, our findings suggest the association between 5-HTTLPR polymorphism and the occurrence of tics and nail-biting as an adverse event of methylphenidate. This may aid in our understanding of the genetic contribution and genetic susceptibility of a particular allele in those ADHD patients with tics or nail biting.ope

2차원 물질 기반 화학저항식 가스 감지 특성 연구

학위논문(박사)--서울대학교 대학원 :공과대학 재료공학부,2020. 2. 장호원.사물과 연결된 모든 사용자 및 기기와 정보교환을 가능케 하는 사물인터넷 기술의 발달에 따라 기기의 내·외부 정보를 교환하는 스마트센서가 가장 중요한 기술로 고려되고 있다. 특히, 가스 센서는 특정 가스의 존재 및 농도를 검지 할 수 있고 인간의 생활, 안전, 건강, 환경, 에너지 절약에 달하는 수많은 영역에 적용 가능하므로 매우 큰 관심을 불러일으키고 있다. 사물인터넷 혹은 차세대 기기에 적용하려면 가스 센서는 저 소비전력, 저가격, 소형화, 현존 기술과의 접목이 쉬워야 하는 점 등 까다로운 요구사항을 전부 만족시켜야 한다. 오늘날까지 반도체성 금속산화물은 대량생산, 소형화, 저가격, 고온 에서의 높은 가스 반응성 등 여러 장점 덕분에 가스감지물질로 가장 많이 사용되어왔다. 하지만 여전히 낮은 선택성, 고 소비전력, 복잡한 합성 방법 등의 주요 문제점 및 거론된 사물인터넷의 요구사항을 해결하지 못한 채, 대체 가능한 가스 감지물질을 탐색하는 연구가 활발히 진행되고 있다. 대안으로 제시되는 물질 중 대표적으로 그래핀, 전이금속 다이칼코게나이드, 금속산화물 나노시트 같은 2차원 물질들이 가장 많은 관심을 받고 있다. 2차원 물질들은 유연성, 높은 비표면적, 많은 활성 사이트, 우수한 상온 가스감지 특성 등 독특하고 우수한 장점들로 인해 금속산화물을 대체하고 미래 기술에 적용 가능하다는 평가를 받는다. 표면 기능화와 귀금속 표면장식을 통해 2차원 물질 고유 성질의 단점을 개선 및 해결하고, 장점은 극대화할 수 있기 때문에 차세대 가스감지물질로 주목을 받고 있다. 또한 상온 가스감지 특성을 보이며 저가격 대량생산 및 소형화가 쉽고, 기존 기술에 적용하기 쉬운 점 등 실제기기 적용의 요구사항을 만족한다. 하지만 2차원 물질도 낮은 선택성, 긴 반응시간 및 회복시간, 비가역적 가스감지 특성과 같은 반드시 극복해야 할 약점들을 가지고 있다. 그러므로, 본 논문은 1) 화학적 합성 방법 중 하나인 수열합성 방법과 2) ultra-sonication을 이용해 물리적으로 합성한 rGO/MoS2 반데르발스 복합체, 3)귀금속이 표면 장식된 MoS2, 위의 세가지 샘플로 준비된 화학저항식 가스센서의 감지 특성을 제시하며, 간단한 공정 과정을 통해 저렴한 가격으로 합성을 진행하고, 표면 기능화를 통해 선택성이 낮은 문제 등을 해결했다. 첫 번째로, 간단한 수열합성 방법을 통해 rGO/MoS2 복합체를 합성하였다. 합성한 물질을 포토리쏘그래피 공정을 통해 제작된 IDE 위에 drop-casting 하여 가스 감지 특성을 확인하였다. rGO/MoS2 복합체를 기반으로 한 센서는 상온에서 습도에 대해 고 감도, 고 선택성, 가역적 감지 반응을 보였다. 이론적 감지 한계는 약 0.01783% RH 수준으로 계산됐다. 두 번째로, 물리적으로 합성한 rGO/MoS2 반데르발스 복합체의 습도 감지 특성을 확인하였다. rGO/MoS2 습도센서는 기타 가스보다 습도에 향상된 반응성, 선택성, 가역성을 보여주었으며, 계산적 상온 감지 한계는 0.0109% RH 정도로 매우 민감했다. 이 센서는 휘어진 형태에서도 안정적인 구동을 보여줄 뿐만 아니라, 장기간이 지난 이후에도 구동이 되는 것이 검증되었다. 이러한 우수한 특성과 손쉬운 제조공정을 이용하여 합성된 rGO/MoS2 반데르발스 복합체는 사물인터넷 및 웨어러블 전자기기 등 차세대 기술에 실제 적용 잠재성을 넓혔다. 세 번째로, MoS2의 표면에 용액공정방법을 이용해 귀금속 나노입자를 장식하고 이를 기반으로 한 가스 감지 특성을 분석하였다. 본 실험에서는 Pd, Au, 그리고 Pt를 MoS2 표면에 합성하였으며, MoS2의 선택성을 향상시켜 2x2 어레이를 구현하였다. 매우 간단한 제조 공정과 우수한 가스 감지 특성을 기반으로 차세대 가스 감지 물질로써 2차원 MoS2 잠재성이 높음을 확인할 수 있는 연구이다.With the development of the Internet of things (IoT) technology that enables information exchange with all users and devices connected to things, smart sensors that exchange information inside and outside the device are becoming the most important technologies. In particular, the gas sensor is of great interest because it can detect the presence and concentration of a gas and can be applied to a number of areas such as human life, safety, health, and environment monitoring. To be applied to the Internet of Things or next-generation devices, gas sensors must meet all the demanding requirements of low power consumption, low cost, miniaturization, and easy integration with existing technologies. To date, semiconducting metal oxides have been used most often as gas sensing materials due to several advantages such as mass production, miniaturization, low cost, and high gas reactivity at high temperatures. However, there is still a lot of efforts in search of alternative gas sensing materials without solving the main problems such as high-power consumption, use of external heater, weak long-term stability, low humidity durability, and the requirements of the Internet of Things. Among the materials proposed as alternatives, two-dimensional (2D) materials such as graphene, transition metal dichalcogenide, and metal oxide nanosheets are receiving great attention. 2D materials are evaluated for their ability to replace metal oxides and be applied to future technologies because of their unique and superior advantages, such as flexibility, high specific surface area, many active sites and good room temperature gas sensing properties. It is attracting attention as the next generation gas sensing material because it can improve and solve the disadvantages of the unique properties of 2D materials through surface functionalization, noble metal decoration, and understanding of the sensing mechanism, and maximize the advantages. In addition, it satisfies the requirements of actual equipment application such as low temperature gas detection, low cost, mass production and miniaturization, and easy to apply to existing technology. However, two-dimensional materials also have disadvantages that must be overcome, such as low selectivity, long response and recovery times, and irreversible gas detection properties. Therefore, this paper is based on a reduced graphene oxide (rGO)/Molybdenum disulfides (MoS2) hybrid composite-based humidity sensor manufactured using 1) chemical fabrication such as hydrothermal methods and 2) mechanical fabrication method. Finally, 3) noble metal decorated MoS2 based gas sensor array are introduced. The detection characteristics of a resistive gas sensor are presented, which solves the problem of power consumption, and low selectivity. First of all, rGO/MoS2 composites were synthesized by a simple hydrothermal synthesis method. The gas-sensing properties were confirmed by drop-casting the synthesized material on the interdigitated electrodes manufactured through the photolithography process. Sensors based on the rGO/MoS2 composites showed high sensitivity, selectivity, and reversible sensing response to relative humidity (RH) at room temperature. The theoretical detection limit was calculated to be about 0.01783% RH level. This sensor not only shows stable operation even in a curved form, but also expands the potential for practical application to next-generation technologies such as the Internet of Things and wearable electronics based on an easy manufacturing process. Secondly, the room temperature and humidity sensing characteristics of the rGO/MoS2 van der Waals composites were confirmed by a simple solution process. Sensors based on the rGO/MoS2 van der Waals composites showed improved response, selectivity, and reversibility to RH over other gases, and the computational room temperature detection limit was very sensitive, 0.0109% RH. This sensor not only shows stable operation even in a bent flexible device but has also been proven to operate as it is after a long period of more than a year. The excellent humidity sensing characteristics, long-term stability and flexible device applications extend the applicability of the actual gas sensor to the rGO/MoS2 van der Waals composites. Thirdly, the noble metal was decorated on the surface of the MoS2 prepared by using a solution process, and the gas sensing properties were measured. In this study, Pd, Au, and Pt were synthesized on the surface of MoS2, and compared to the case of using pristine MoS2, the selectivity was improved. Based on a very simple manufacturing process and excellent gas sensing characteristics, it is possible to confirm the potential of two-dimensional MoS2 as the next generation gas sensing material.Chapter 1. Chemoresistive gas sensing of two-dimensional materials: Principles and leading materials 1 1.1. Introduction 2 1.2. Basics of chemoresistive gas sensors 7 1.2.1. Principles of gas sensing mechanisms 7 1.2.2 Gas sensor parameters 11 1.2.3. Three basic factors for chemoresistive gas sensing 15 1.3. Two-dimensional materials for chemoresistive gas sensing 17 1.3.1. Graphene-based gas sensors 17 1.3.2. Transition metal dichalcogenides based gas sensors 22 Chapter 2. Room temperature humidity sensors based on rGO/MoS2 hybrid composites synthesized by hydrothermal method 26 2.1. Introduction 27 2.2. Experimental section 30 2.2.1. Synthesis of MS-GO 30 2.2.2. Sensor fabrication 31 2.2.3. Material characterization 31 2.2.4. Sensor measurements 32 2.2.5. Flexible Device 32 2.3. Result and discussion 33 2.3.1. Fabrication process and electrical properties 33 2.3.2. Gas sensing properties of MS-GO 41 2.3.3. Sensing performance with flexible substrate 49 2.3.4. Gas Sensing Mechanism 51 2.4. Conclusion 53 Chapter 3. Highly selective and sensitive chemoresistive humidity sensors based on rGO/MoS2 van der Waals composites 54 3.1. Introduction 55 3.2. Experimental section 57 3.2.1. Preparation of graphene oxide (GO) 57 3.2.2. Reduction of GO 58 3.2.3. Fabrication of RGMS hybrid composites 58 3.2.4. Sensor fabrication 59 3.2.5. Characterization 59 3.2.6. Sensor measurement 60 3.3. Result and discussion 60 3.3.1. Fabrication process and electrical properties 60 3.3.2. Gas sensing properties of MS-GO 74 3.3.3. Sensing performance with flexible substrate 84 3.3.4. Gas sensing mechanism 86 3.4 Conclusion 89 Chapter 4. Highly selective noble metal decorated MoS2 based gas sensor array 90 4.1. Introduction 91 4.2. Experimental section 93 4.2.1. Fabrication of metal nanoparticles on MoS2 93 4.2.2. Sensor fabrication 94 4.2.3. Characterizations 94 4.2.4. Sensor measurements 95 4.3. Result and discussion 95 4.3.1. Fabrication process of metal decorated MoS2 95 4.3.2. Characterization of metal decorated MoS2 101 4.3.3. Gas sensing properties 108 4.4. Conclusion 112Docto

Vessels encasing traces of slip : focusing on multiple casting

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The Determinants of Migrants Experience of Discrimination: Considering Structural, Cultural, and Environmental Perspectives

본 연구는 외국인의 차별경험에 미치는 영향요인을 구조적･문화적･환경적 관점에서 파악하는데 목적이 있으며, 한국인이 아닌 외국인의 입장에서 분석하였다는 점에서 기존 연구와 차별화된다. 분석을 위하여 숙명여자대학교 다문화통합연구소와 법무부 출입국･외국인정책본부가 함께 조사한 2011 한국 내 재외동포 및 외국인 전문기술직 실태조사를 활용하였으며, 전국에 거주하는 약 1,000명의 외국인을 분석대상으로 설정하였다. 연구 결과, 첫째, 구조적 관점의 인종이나 피부색은 외국인의 차별과 배제에 유의미한 영향을 미치고 있었다. 둘째, 구조적 관점의 출신국적에서는 후진국 출신의 외국인일수록 차별을 경험하는 것으로 나타났다. 셋째, 문화적 관점에서 한국어 능력은 그 수준이 낮을수록 차별을 받게 하는 요인으로 도출되었다. 넷째, 환경적 관점의 주거환경 안전은 외국인의 차별에 유의미한 영향을 미쳤으며, 안전함이 낮은 곳에 거주하는외국인일수록 차별을 보다 많이 경험하는 것으로 나타났다. 이러한 연구 결과를 토대로 외국인의입장에서 차별과 배제를 완화하기 위한 다문화정책을 마련하고자 할 때, 필수적으로 고려해야 할 요인을 제시했다는 점에서 본 연구는 정책적 함의를 가지고 있다.This study examines the determinants of discrimination against migrants from their standpoint. It considered factors affecting discrimination in terms of structural, cultural, and environmental perspectives. The data come from the 2011 Migrants Survey collected from 1,000 migrants living across the country by the Sookmyung Institute of Multicultural Studies and the Korea Immigration Service. The empirical analysis shows that race/ethnicity and skin color are associated with migrantsexperience of discrimination. In addition, migrants from developing countries, not fluent in Korean, and those living in unsafe residential areas are more likely to experience discrimination. The findings in this study provide important information for developing multicultural policies that can reduce discrimination against and exclusion of migrants.이 논문은 2016년 대한민국 교육부와 한국연구재단의 지원을 받아 수행된 연구임(NRF-2016S1A3A2925463)