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A Study on the Development of an Expert System to Diagnose Lightning Arrester Deterioration
Full text linkThis thesis deals with an effect of a single and a quadruple lightning impulse currents on electrical characteristics of ZnO blocks, and an expert system to diagnose deterioration of arresters.
Lightning arresters are the best protective device on electric power systems to transient overvoltages caused by lightning discharge and switching operation. Though there have been accomplished technical and economical renovations by the development of a ZnO block having excellent nonlinear I-V resistive characteristics, substantial parts of the power system failures are still occupied by deterioration of lightning arresters.
Electrical characteristics of ZnO blocks are deteriorated by repeated impulse current, and the deteriorated ZnO block is brought to a thermal runaway and finally destroyed. It is therefore important to estimate the change of electrical characteristics of ZnO blocks.
In this study, an accelerated deterioration test is carried out to deduce the parameters needed for diagnosing arrester deterioration, and leakage current components are measured. Also, wave height distribution of the leakage current with the progress of arrester deterioration is analyzed.
From the experimental results, the wave height distribution of the leakage current showed a conspicuous difference even in an immaterial leakage current increase. The use of wave height distribution of the leakage current in deterioration diagnostic technique makes more accurate diagnosis than the conventional method using only a leakage current value. Finally, the expert system based on the experimental results is developed, and the effectiveness of the system is estimated in a 18[kV] lightning arrester, a 72[kV] and a 170[kV] gas insulated switchgear system.목차
목차 = i
그림 및 표목차 = ii
Abstract = iv
제 1 장 서론 = 1
제 2 장 이론 = 5
2.1 피뢰기의 구조 및 특성 = 5
2.2 열화진전기구 = 12
2.3 열화진단기술 = 14
제 3 장 뇌충격전류에 의한 가속열화시험 = 23
3.1 실험장치 및 방법 = 23
3.2 동작개시전압 및 누설전류의 변화 = 30
3.3 열화진전에 따른 누설전류의 파고분포 = 34
제 4 장 열화진단 전문가 시스템 및 적용 평가 = 36
4.1 열화진단 전문가 시스템 = 36
4.2 적용 실험 = 44
제 5 장 결론 = 54
참고문헌 = 5
(A) Study on Characteristics of Microstrip Dipole Array Antenna Using Electromagnetic Coupled Technique for DBS Reception
Full text linkThis thesis describes a characteristics of microstrip EMC (Electro-Magnetic Coupled) cross dipole array antenna with circular polarization. EMC cross dipole array antennas are attractive elements with the desirable properties such as simplicity, small size, and circular polarization.
This thesis is composed of five chapters including the introduction. The chapter 2 explains a design for microstrip EMC cross dipole antenna element with a circular polarization and a wide bandwidth. The circular polarization is obtained by the X-shaped cross dipole radiation element. The wide bandwidth is realized by EMC technique. The antenna characteristics are analyzed by the Ensemble and the FDTD (Finite Difference Time Domain) method with Mur's 2nd order ABC (Absorbing Boundary Condition). The radiation power for uniform illumination in an array design is also controlled by offset parameters.
In the chapter 3, T-junction power splitter is presented. The characteristics of reflection and transmission coefficients were calculated.
The chapter 4 shows the performance of array antenna. The 20-element array antenna was designed and fabricated. The measured results agreed with the calculated ones. The beam-tilt characteristics are numerically obtained by control of element distance. The proposed beam-tilt antenna can be applied for DBS (Direct Broadcasting from Satellite) reception. When the distance between elements is 12 mm at 12 GHz, the radiation angle of array antennas is obtained -45°beam-tilt. Furthermore, the 40- and 80-Element beam-tilt array antennas were proposed for realizing high gain. By control of the element distance on the feed line in design, the array antennas with high gain and beam tilting angel of -45°could be realized. The axial ratio of 0.1 dB below was designed for the wide bandwidth. However, future work is to suppress the high grating lobe.
Then, it was concluded in the chapter 5.Abstract
제 1 장 서론 = 1
제 2 장 EMC cross dipole 복사소자 = 3
2.1 안테나 구조 = 3
2.2 안테나 설계파라미터 = 5
2.2.1 다이폴 높이에 의한 반사계수 = 5
2.2.2 비유전율에 의한 반사계수 = 6
2.2.3 cross dipole 각도에 의한 반사계수 = 7
2.2.4 다이폴의 길이에 의한 반사계수 = 7
2.3 최적 설계파라미터 = 8
2.4 offset에 따른 특성변화 = 11
2.5 검토 = 12
제 3 장 급전회로 = 14
3.1 T-junction Power Splitter = 14
3.2 계산결과 = 15
제 4 장 EMC cross dipole 어레이 안테나 = 17
4.1 10소자 어레이 안테나 = 17
4.2 20소자 어레이 안테나 = 18
4.3 어레이 안테나의 빔 틸트 특성 = 22
4.3.1 10소자 어레이 안테나의 빔 틸트 = 23
4.3.2 20소자 어레이 안테나의 빔 틸트 = 27
4.3.3 40소자 어레이 안테나의 빔 틸트 = 30
4.3.4 80소자 어레이 안테나의 빔 틸트 = 32
4.3.5 어레이 안테나의 축비 및 이득 = 35
4.4 제작 및 실험 = 38
4.5 검토 = 40
제 5 장 결론 = 42
참고문헌 = 4
A Study on Knowledge Competitiveness Strategy for Korean Shipping Companies in the Shipping Environment Change
Full text linkRecent initiatives in the logistic environment of the shipping industry have corporations increasing their efforts to meet their organizational goals and to stay competitive in the market. Recent initiatives to improve organization management and organizational restructuring are good examples. Shipping companies face difficult challenges such as lowering their debt ratio, which arose from economical crisis implemented by International Monetary Fund, below two hundred percent. Also, along with manufacturing markets, the shipping market has experienced the effects of globalization. New focus on global customer value through global management became crucial aspects of business and a primary factor of success. The increased diversity that a global markets presents brought new challenges since customers needs vary greatly. Also, shipping markets face the inherent fluctuation of international exchange rate changes.
In order to survive, as an international marine transportation company, companies must maximize their competitiveness in this uncertain environment through high tech hedging techniques, focusing on efficient customer satisfaction management as well as obtaining a knowledge based competitive edge.
That is to say, it is required to have knowledge mind which enables organizations to meet the challenges of internal and external situations of the shipping industry. And also, it is necessary to build the organizational structure, which support customer demands through creative administrative techniques. For these the vision and strategy should be established curiously and the support and investment of CEO have to be attended smoothly to support. Also, marine transportation company might lose competitive power if there is no customer value for abstract marine services being offered like that of general company especially in marine transportation. This target customer group is not only domestic but also global customer and differs from the past time. So, there is need for thinking globally and having a customer focus that support customer value if theres no customer value for global customer, we could not improve our marine transportation company to world best.
Especially, contrary to the former times, the field of marine transportation business targets the international market as well as the domestic market. Therefore, if we couldnt create the merit for our customers with global business mind, we wouldnt become a global corporation of marine transportation. To accomplish the global project and acquire the competitive power, the inner-process in organization of shipping circumstances is considered the most important. The downsizing of duplicate organizations in shipping corporations is often accompanied. So, the members of shipping corporations feel uneasy and insecure about the downsizing and it must do harm to the competitive power of the organization. With minimizing negative influence of organization in the shipping circumstances, suggestion of the vision for members of the corporation to participate in developing the corporation, improving the inner-process, the effect of the shipping circumstances can be maximized. In this point of view, Kaplan and Nortons The Balanced Scorecard Model is the intellectual business model that suggests the way by which the competitive power of the organization can be measured adequately to improve the competitiveness.
Kaplan and Norton view that not only on enterprise organization but also all organizations utilize strategy and vision, internal organization process, studying and innovation, financial factors and customers value as core-organization and measurance factors to maintain competitiveness to deal with internal and external environmental changes pertinently, and these factors will control organizational competitiveness.
So, this treatise aims to diagnose outer port enterprises competitive level on enterprise competitive measurance factors which is presented by Kaplan and Norton, and to present plans to raise knowledge competitiveness of a shipping company which cause to trend organization value with marine transportation service capacity to fulfill various global customers demanding conditions and new management method and conductible organization system and clear setting of vision and strategy.
For statistical inference, the Reliability Analysis (Cronbachs Alpha-Test) method, the Factor Analysis Method, Correlation Analysis and the Structural Equation Modeling (SPSS AMOS4.0) are used to examine relationships between the four factors from Balanced Scorecard Model and the dependent variables such as the capabilities for handling external and internal environmental changes in the shipping industry.
The following listed results for this study are manifested through the above mentioned various statistical processes.
First, in order for shipping companies to enhance their competitiveness in the uncertain marine transportation environment, balance between financial and non-financial results needs to be established. Second, under competitive marine environment, organizations need to make their employee understand organizational strategy and focus on constant management reform to create new customers and improve organizations image in the industry. Furthermore, organizations can not neglect maximizing employee satisfaction and work ability within them. Therefore, a reward system that compensates for beneficial ideas at organizational level is necessary and employers as well as employees should be on the same intellectual management mode and introduction and application of advanced marine transportation technique is required. Third, employee who is related with shipping industry field and meeting stockholders expectation play a big role in accretion of organization value. These factors show similar effects as creating new customers and (improvement of organization image) at the organizational level. Especially, improvement of internal process such as open communication channel, information sharing and adequate strategic use of information assets is required. Also market research and analysis, ability to adapt to market environment, management reform based on customer satisfaction arose as main focus. Fourth, to evaluate the correlation between financial outcomes (market share, sale growth, and productivity) assessment of financial standpoint (effort to reduce expense, financial structure improvement, efficient application of assets and economic value added) is thought to be the most critical aspect. In addition, to maximize financial outcome comparatively high cost cut (government support is essential), financial structure improvement, efficient application of asset (especially ships), and profit centered operation focusing on economic value added are considered necessary.목차
Abstract
제1장 서론 = 1
제1절 연구필요성과 연구목적 = 1
1. 연구필요성 = 1
2. 연구목적 = 2
제2절 연구내용과 연구방법 = 4
제2장 해운환경변화와 외항선사의 SWOT분석 = 6
제1절 외항선사의 선박보유와 경영현황 = 6
1. 외항선사의 현황 = 6
2. 외항해운산업의 경영환경 = 11
3. 외항선 보유현황 = 13
제2절 외항선사의 경영환경 실태조사분석 = 17
1. 해운환경 변화분석과 진단 = 17
2. 외항선사 경쟁력 저하요인분석과 진단 = 20
제3절 외항선사의 경영실태분석 = 23
1. 수？暠？ 분석 = 24
2. 재무구조 분석 = 26
3. 자산 및 자본의 효율성 분석 = 27
4. 생산성 분석 = 29
5. 한국해운산업 경영실태분석 요약 = 31
제4절 외항선사의 SWOT 분석 = 33
1. 위협요인 = 34
2. 기회요인분석 = 34
3. 문제점(취약점)요인 = 35
4. 강점요인 = 36
5. SWOT 분석결과와 지식경쟁력강화 필요성 = 36
제3장 지식경영모형에 관한 이론적 배경과 선행연구 = 38
제1절 지식의 개념과 지식경영의 흐름 = 38
1. 지식의 개념 = 38
2. 지식경영의 정의와 연구흐름 = 42
제2절 균형성과모형의 내용과 조직발전의 유용성 = 52
1. 균형성과모형의 내용 = 53
2. 외항선사조직의 경쟁력 평가에 균형성과모형의 유용성 = 56
3. 균형성과모형에 의한 지식경쟁력 강화과정 = 64
제3절 지식경쟁력강화를 위한 전략과 관점 추출 = 66
1. 전략 도출과 관리를 위한 핵심프로세스 = 66
2. SWOT 분석결과의 진단 = 68
3. 외항선사의 비전과 지식경영전략 도출 = 70
4. 외항선사조직의 지식경쟁력 관점요인 = 73
제4장 외항선사의 지식경쟁력강화전략 구축을 위한 실증연구 = 77
제1절 연구모형 설정과 변수측정 = 77
1. 연구모형과 연구가설 설정 = 77
2. 변수의 조작적 정의와 측정방법 = 82
3. 자료수집과 분석방법 = 86
제2절 지식경쟁력강화를 위한 분석결과와 해석 = 88
1. 요인들의 경로분석과 상관관계분석 = 88
2. 요인들의 신뢰성과 타당성진단 = 91
3. 구조방정식에 의한 경로분석과 가설검증 = 98
제5장 결론과 시사점 = 104
제1절 분석결과의 요약 = 104
제2절 연구결론의 시사점 = 106
제3절 연구의 한계 = 107
[참고문헌] = 108
[부록I] 설문지 = 115
[부록II] 연구시사점 도표 = 12
Design and Implementation of a SMIL-based Web Editor for Multimedia Teaching Aids
Full text linkAs WWW becomes the representative service of Internet, HTML has revealed it's limitation on processing multimedia data. Many other techniques - like DHTML and Java - were introduced. They, however causes heavy traffics on the network and overhead on web browsers. The Synchronized Multimedia Integration Language (SMIL) is a recommendation from the W3C that makes authoring of TV-like multimedia presentations on the Web easier. It is derived from the eXtensible Markup Language (XML) to define a set of markup tags to synchronize the timing and positioning relationships between multimedia objects. This paper presents the design and implementation of a SMIL-based web editor. The proposed editor handles well the temporal and spatial synchronized information among multimedia objects. It was, especially designed for multimedia teaching aids. The easy user interface and convenient tools are the essential needs for the teachers unfamiliar to the multimedia authoring. Then the user interface with WYSIWYG and Drag & Drop is the main theme in designing the SMIL editor. Now novice users are able to make complicated multimedia presentation in more ease and convenience.Abstract = ⅱ
제 1 장 서론 = 1
제 2 장 SMIL 소개 = 4
제 3 장 SMIL 문서 에디터 설계 = 12
3.1 공간 정보 설정 = 12
3.2 시간 정보 설정 = 14
3.3 설정 정보의 저장 = 16
제 4 장 구현 = 22
4.1 전체 구성 = 22
4.1.1 기본 메뉴와 툴바 = 24
4.1.2 탭 컨트롤 = 25
4.2 공간 정보 설정 윈도우 = 25
4.2.1 WYSIWYG 화면 = 26
4.2.2 상세 정보 설정 화면 = 27
4.3 시간 정보 설정 윈도우 = 28
4.3.1 멀티미디어 객체 추가 버튼 = 28
4.3.2 시간축 편집기 = 29
4.4 데이터베이스 = 31
제 5 장 결론 = 33
참고 문헌 = 3
An Empirical Study on Improving the Terminal Operating Company Scheme in Korea
Full text linkPrivatisation has emerged within the past few decades as one of the most significant challenges to public ports and their governments throughout the world. More than forty countries have committed to some form of port privatisation thus far, and they will quite likely be joined by dozens more by the turn of the century.
A decision to privatise ports can be driven by a variety of forces. The most obvious is to relieve a financially strapped government by turning to the private sector for an infusion of capital required to modernise and sustain port operations, or to bolster the national treasury.
Inefficient and costly port operations can seriously impair the competitiveness of a nation's export industries and artificially raise the cost and thus constrain the availability of imported goods. Privatisation in certain circumstances, therefore, holds the promise of stimulating economic growth particularly for those whose livelihood depends directly upon port activity and trade.
The main objective of this study is, first of all, to introduce a variety of methods of port privatisation after reviewing the reason why port facilities should be privatised. This paper also aims to make some proposals with which a port privatisation process in Korea can be improved after summarising the present Terminal Operating Company(TOC) system propelled by Ministry of Maritime Affairs and Fisheries.목차
표목차 = iii
그림목차 = v
Abstract = vi
제1장 서론 = 1
1.1 연구배경 및 목적 = 1
1.2 연구의 방법과 구성 = 2
제2장 주요국 항만관리 및 운영 제도의 변화 = 4
2.1 전통적 항만관리운영의 유형 = 4
2.2 항만관리운영과 규제완화(deregulation) = 12
2.3 주요국 항만관리제도의 개혁 = 19
2.4 주요국 항만운영제도의 개혁 = 25
제3장 항만민영화와 우리나라의 추진현황 = 31
3.1 항만의 민영화 배경 = 31
3.2 항만의 민영화 방법 = 34
3.3 우리나라 항만관리운영제도의 현황 및 문제점 = 50
3.4 우리나라 항만민영화의 추진현황: 부두운영회사(Terminal Operating Company) = 53
제4장 부두운영회사(TOC)제도의 환경분석과 활성화 방안 = 71
4.1 TOC제도의 환경 분석 = 71
4.2 TOC제도의 활성화 방안 = 91
제5장 요약 및 결론 = 99
참고 문헌 = 102
설문지 = 10
A Study of Wave Control by Floating Breakwaters
Full text linkMainly, Floating Breakwaters(FBs) have been constructed in many coastal regions due to the advantages of the coastal environment and construction cost. In general, the FB becomes fixed or its width broadened because the movement of the FB comes to be large and its the wave control function lower for the long period incident waves.
In this study, efficiency of the FB is evaluated for various mooring systems using Eigenfunction Expansion Method(EEM) in two-dimensional wave field. And, the wave control function of two-rowed Fixed Floating Breakwaters(FFBs) that have narrower width than that of the one-rowed FFB is discussed by using Boundary Element Method(BEM) based on the Green formula and EEM. The validity of the present study is confirmed by comparing it with the results of Ijima et al.(1974) and Yosida et al.(1992) for the one-rowed Fixed Floating Structure. Of mooring forms, Open Catenary Mooring is the best one about the transmission ratio, sway, heave, roll motion, and mooring line force. It is revealed that the wave control function of two-rowed FFBs is more effective than that of the one-rowed FFB.목차
ABSTRACT = i
要約 = ii
目次 = iii
그림目次 = v
第1章 序論 = 1
1.1 本 硏究의 背景 = 1
1.2 本 硏究의 目的과 構成 = 2
第2章 固有函數展開法에 의한 2次元 波動場 解析 = 3
2.1 理論解析 = 3
2.1.1 支配方程式과 境界條件 = 3
2.1.2 流體運動과 空間速度포텐셜의 一般解 = 5
2.1.3 浮防波堤의 運動方程式 = 7
2.1.4 速度포텐셜의 未定係數 決定 = 11
2.1.5 波의 變形係數 = 14
2.2 數値解析 = 15
2.2.1 Open Mooring = 16
2.2.2 Vertical Mooring = 18
2.2.3 Cross Mooring = 20
2.2.4 Open Catenary Mooring = 22
2.2.5 Cross Catenary Mooring = 25
第3章 境界要所法과 固有函數展開法에 의한 3次元 波動場 解析 = 27
3.1 理論解析 = 27
3.1.1 支配方程式과 境界條件 = 27
3.1.2 空間速度포텐셜 φ(x, y, z) 의 表示 = 28
3.1.3 Green 公式과 포텐셜 函數 φ(x, y) = 31
3.1.4 Green 函數에 의한 f₁, f₁^(n), ψ_o, ψ_s, φ_o, φ_s 의 表示 = 36
3.1.5 各 領域에서의 接合境界條件 = 38
3.1.6 離散化 = 41
3.1.7 回折係數 = 46
3.2 數値解析 = 47
3.2.1 數値解析結果의 檢證 = 47
3.2.2 二列 二基 配置에 의한 波高分布의 解析 = 47
3.2.3 二列 三基 配置에 의한 波高分布의 解析 = 55
第4章 結論 = 65
> = 66
Appendix = 6
A Study on Management Measures for Coastal Landscape in Busan City
Full text linkDue to the difficult accessibility of the Busan coastline to its citizens, this waterfront area has lost it's amenity. Because Busan coastline has primarily been utilized for industry and transportation there is a threat of serious destruction to the coastal environment and landscape. This problem is compounded by the rapidly increasing demand for coastal development in this area.
In addition there is little understanding of coastal management systems in this area and Busan, as a city, does not have any management measure for coastal landscapes. So there is a necessity for systematic management systems to restore and preserve this natural coastal landscape and its associated ocean resources.
The purpose of this study is to investigate domestic and foreign coastal landscape management systems in order to propose reform measures for improvement of coastal landscape management in Busan city.
The results of this study are as follows.
Firstly, domestic coastal landscape management systems are compartmentalized into urban planning part, coastal management part and environmental preservation part without comprehensive laws or integrated management measures.
On the other hand, in the United States of America and Japan coastal landscape management measures are established according to separate regional characteristics in order to protect and manage coastal landscapes through specification of special districts. These management measures are protected by legislation.
In Busan coastal landscape management measures have been rare because several administration departments preside over coastal landscape management individually under the separated law. As a result of this, coastal landscape management has been ineffective and there have been no integrated management measure for coastal landscaping. Especially coastal landscaping is managed under the urban management systems.
These findings indicate that the coastal landscape is in need of synthetic management in the form of coastal management rather than urban planning because coastal landscape is different from urban landscape by nature. Therefore coastal landscape management should be achieved through coastal landscape management ordinance which is based on the Coastal Management Act. And the zoning system for costal landscape management is to be set up under the coastal landscape management ordinance. Using the zoning system the coastal area can be divided into three costal landscape districts, the coastal landscape conservation district, coastal landscape restoration district and the coastal landscape plan district, which have the special characteristics of the coastal landscape individually.
Then rapid establishment of guidelines for coastal landscape planning and design are mandatory. Also Busan city government and the district office must manage their coastal landscape effectively through wholly responsible departments, experts and coastal landscape review committees.목차
Abstract
1. 서론 = 1
1.1 연구의 배경 및 목적 = 1
1.2 연구의 내용 및 방법 = 3
2. 해안경관에 대한 이론적 고찰 = 5
2.1 해안경관의 개념 = 5
2.2 해안경관의 구성요소 = 7
2.3 해안경관의 관리범위 = 10
3. 국내 해안경관관리제도의 분석 = 13
3.1 도시계획측면 = 15
3.1.1 부산광역시 = 17
3.1.2 인천광역시 = 18
3.1.3 제주도 = 20
3.2 연안관리측면 = 21
3.3 환경보전측면 = 24
3.3.1 자연환경보전법 = 24
3.3.2 환경교통재해 등에 관한 영향평가법 = 26
3.4 소결 = 29
4. 국외 해안경관관리제도의 분석 = 32
4.1 일본？Ь홴돕？ = 32
4.1.1 도시계획측면 = 32
4.1.2 연안관리측면 = 45
4.2 미국연안도시 = 48
4.2.1 도시계획측면 = 48
4.2.2 연안관리측면 = 58
4.3 소결 = 59
5. 부산의 해안경관관리 개선방안 = 61
5.1 부산의 해안경관관리 현황 및 문제점 = 61
5.1.1 경관관리행정조직 = 61
5.1.2 해안경관관리현황 = 63
5.1.3 부산해안경관관리의 문제점 = 65
5.2 부산의 해안경관관리 개선방안 = 65
5.2.1 제도적 측면 = 65
5.2.2 운영적 측면 = 66
5.2.3 통합적인 해안경관관리방안 = 67
6. 결론 = 70
참고문
A Study on the Estimation of Discharge Amount of NOхEmission from Ships in Port of Busan
Full text linkRecently controlling of air pollutants emission from onboard ship as well as on land has become more important issue. New Annex VI to MARPOL 73/78 and IMO NO_x Technical Code were adopted by the IMO.
Particularly from the year 2000, according to Regulation 13 Nitrogen Oxides(NO_x) of the Annex VI, this regulation shall apply to new marine diesel engines greater than 130 kW installed on vessels constructed on or after January 1,2000, or which undergo a major conversion after that date and most of engines which are being currently built should be tested and surveyed in accordance with NO_x Technical Code.
In order to prevent the port city from air pollution, we have to know how many tons of NO_x emit from ships in all port city and we should make our own implementation schedule depending on our country's status.
For this purpose, this study investigates the discharge amounts of nitrogen oxides(NO_x) from all ships in the port. But it is difficult to survey for the discharge amounts of NO_x from all ships in a porty city due to time and cost.
Marine engine power is very related to Gross tonnage of ship and the amount of NO_x emission is related to engine power. Therefore the method of calculation can be obtained from these relationships.
So this report proposed the method of calculation without onboard survey. With the comparison and analysis of other countries emission control regulation, author proposed basic data of total discharge NO_x emission from ships in the port and future emission control standard in our country. Especially, this report focused on port of Busan, because marine traffic of Busan is very intensified.
From the Busan Regional Maritime Affairs and Fisheries office, ships types were classified into container ship, bulk carrier, general cargo ship, passenger ship.
Marine engine power is directly related to Gross tonnage of ships therefore aregression across four ship types was performed by using KR registration data statistically.
As the result, the estimation results reveal that total discharge amount from ship is large unexpectedly , but there is few report that NO_x emission from ship will have an effect on the coastal environment. Thus its effect should be investigated in order to search the proper procedures against air pollution.
The more study will need to research OCD(Offshore and Coastal Dispersion)model for coastal environment effect.목차
Abstract = iii
제1장 서론 = 1
1.1 연구배경 = 1
1.2 선행연구현황 및 연구목적 = 6
제2장 NO_x의 생성 및 환경에 미치는 영향 = 8
2.1 NO_x가 오존생성에 미치는 영향 = 10
2.2 NO_x가 환경에 미치는 영향 = 10
2.3 NO_x 생성기구 및 분류 = 14
제3장 선박으로부터의 NO_x 배출량 산정방법 = 16
3.1 NO_x 산정방법 개요 = 16
3.2 부산항의 선종별 입·출항 통계자료 = 19
3.3 총톤수와 기관출력의 상관관계 = 21
3.3.1 선형회귀분석의 개요 및 방법 = 21
3.3.2 총톤수와 기관출력의 관계식 I = 24
3.3.3 총톤수와 기관출력의 관계식 II = 26
3.3.4 어선을 제외한 모든 선종의 선형회귀분석 = 33
3.4 부산항의 부두별 거리와 소요시간 및 정박시간산정 = 35
3.4.1 입·출항 거리와 소요 시간 = 36
3.4.2 정박시간 산정 = 38
3.5 NO_x 배출량 산정방법 = 38
3.5.1 부하율을 이용한 방법(산정식I) = 38
3.5.2 부하별 실측자료를 이용한 방법(산정식II) = 39
제4장 NO_x 배출량 산정방법에 의한 결과 = 43
4.1 NO_x 배출량 계산 방법 I = 43
4.1.1 입·출항시 NO_x 배출량 계산 = 43
4.1.2 정박중 NO_x 배출량 계산 = 45
4.1.3 계산 결과 = 45
4.2 NO_x 계산 방법 II = 46
4.3 NO_x 계산 방법 III = 47
4.4 NO_x 계산 방법의 결과 비교 = 49
제5장 실자료와의 비교 검토 = 51
5.1 선박의 총톤수와 기관출력과의 관계식 검토 = 51
5.2 NO_x 배출량 산정식과 실제엔진 측정치의 비교 = 52
결론 = 59
참고문헌 = 6
(A) Study on the assessment of the marine traffic safety at the Pusan approaching waters
Full text link(1) the present traffic condition shows some difficulties in traffic lanes 2 & 8(to and from Japan), and 3 & 9(to and from South coast),
(2) the comparisons, generally, indicate lower ESA value in suggested roundabouts(TSS) than the present traffic measure, however,
(3) the roundabouts(TSS) make the traffic lane 1(from Pusan to East coast)and 9(form South coast to Pusan) longer naturally.
Eventually, this paper conclude that the ESA model is a useful technique to assess the traffic safety and the suggested roundabouts(TSS) could make the concerned area safer than present traffic situationMarine traffic engineering is the technical field that observe flows of vessel traffic in accurate and describe the features of ships' movement statistically or analytically, then contribute to the improvement of the traffic flow and safety of traffic.
Recently, marine traffic engineering has been developed until that possible to estimate a changes in traffic flow caused from some transformations of the traffic condition, and to assess the feasibility and validity of the changes by computer simulation.
This paper aims to assess the present traffic safety at the sea area adjacent to Pusan harbour, and the validity of the suggested roundabouts TSS at the Pusan approaching water(by Park in 1998(1)) using ESA(Environmental Stress Aggregation) model
There are couple of steps to describe the marine traffic situation and to assess it's safety by computer simulation. The first step is observe the movement of vessel traffic concerned waters and to obtain the relevant data for computer simulation which is described in Chapter 3. A series of traffic surveys were conducted for 4 days and obtained valuable data including the tracks of the vessels, traffic volume, type and size of ships, and etc.
Second step is to carry out computer simulation to assess the simulated traffic flows by using suitable indexes of assessment model - ESA model.
Earlier studies and some theoretical backgrounds were examined in Chapter 2, the simulation process and valuable outputs from the simulation were described in Chapter 4.
The last step is to compare the results of assessment on the present traffic situation with the expected one by using suggested changes. The last part of Chapter 4 and Chapter 5 explains the results thatAbstract = ⅵ
제 1 장 서론 = 1
1.1 연구의 배경 및 목적 = 1
1.2 연구의 방법 및 내용 = 2
제 2 장 해상교통의 안전성평가이론 = 3
2.1 해상교통의 안전성평가에 대한 고찰 = 3
2.2 교통관측조사와 Simulation에 의한 해상교통현상의 예측 및 재해 = 7
2.2.1 해상교통현상의 파악 = 7
2.2.2 Simulation에 의한 해상교통현상의 예측 및 재현 = 11
2.3 종합환경 스트레스 평가(ESA) 모델 = 30
2.3.1 조선환경 스트레스 치(ESL Value) = 31
2.3.2 교통환경 스트레스 치(ESS Value) = 35
2.3.3 종합환경 스트레스 평가모델 = 38
제 3 장 부산항 교통관측조사 = 40
3.1 부산항 교통관측조사 = 40
3.1.1 조사일시와 인원 및 장비 = 40
3.1.2 관측방법 = 41
3.2 관측조사결과 43
3.2.1 선박항적분포 = 43
3.2.2 선박교통량 = 47
3.2.3 선형분포 = 49
제 4 장 시뮬레이션에 의한 부산항교통류 평가 = 51
4.1 선박의 발생모델 = 51
4.2 선박의 항행모델 및 피항조선 = 54
4.3 시뮬레이션 결과 = 54
4.3.1 발생선박항적 = 55
4.3.2 발생선박척수 및 선형 = 56
4.4 원형분리대에 의해 정류된 교통류의 예측 및 재현 = 57
4.4.1 통항경로대의 재분류 = 58
4.4.2 발생선박항적 = 61
4.4.3 발생선박척수 및 선형 = 62
4.5 재현된 교통류의 평가 = 63
4.5.1 평가방법 = 64
4.5.2 평가결과 = 66
제 5 장 결론 = 72
5.1 연구의 결과 = 72
5.2 금후의 과제 = 7
(A) Study on the High Power Factor Control in a Boost Rectifier
Full text linkThe boost converter operating at the boundary of continuous conduction mode(CCM) and discontinuous conduction mode(DCM) in the inductor output current of the converter has been commonly and widely used as one of the power stable control devices.
This converter can achieve the power factor correction by minimizing the harmonic distortion in the input current of the circuit.
This paper examines an advanced boost converter based on the above proto-type converter to obtain more stable and constant DC power source.
In order to compose the converter, first of all, a filtering capacitor is added across the output of the bridge rectifierthis capacitor is to filter the high-frequency switching noise so that the voltage reference for the control circuit is a clean sinusoidal wave, and a switching control circuit to decrease the harmonic distortion is connected.
Furthermore, optimum parameter values to minimize the harmonic distortion in the input current are derived from the analyses of switching characteristics, switching on-off time and switching frequency.
Based on the analyses, a simulation using the PSim was done and a 100[W] step-up converter was designed and fabricated. As a result, it has been found that the power factor of 14[%] was improved compared to the proto-type boost converter.Abstract
1. 서론 = 1
2. 일반적인 정류기 = 3
2.1 부스트 정류기의 등가회로 = 8
2.2 부스트 정류기의 동작해석 = 12
2.2.1 스위칭 시간에 따른 인덕터 전류의 특성 = 12
2.2.2 출력 전압과 리플 = 17
2.3 효율과 스위치 저항과의 관계 = 19
3. 시스템 설계 = 24
3.1 고역률 부스트 정류기 시스템 = 24
3.2 시뮬레이션 = 33
3.3 시스템 설계 및 제작 = 36
4. 실험 결과 및 고찰 = 40
5. 결론 = 44
참고 문헌 = 4