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Delay Predictive Modeling on the Diverge Sections of Urban Freeway Interchange based on Real-Time Traffic Characteristics
Get PDFGenerally urban freeway is the principal arterial corridor that is intended to provide for high levels of safety and efficiency in the movement of high-volumes of traffic at high speeds in the big city. However, most of the urban freeways are experiencing a severe congestion with the incoming or outgoing traffic through the freeway interchange regardless of the peak periods. Thus, the purpose of this study is to investigate and analyze the real-time traffic characteristics, and construct the travel delay predictive models on the diverge sections in the congested urban freeway interchange in city of Busan.
From the results of the real-time traffic characteristic analyses, construction and verification for the delay predictive models on the diverge sections of the urban freeway interchange under the study, the following conclusions were drawni) Traffic flow showed a big difference depending on the time periods in the urban freeway interchange. Particularly more traffic were concentrated on the urban freeway interchange in the daytime period when compared with the nighttime period.
ii) Traffic flow also showed a quite difference depending on the travel directions in the urban freeway interchange. Particularly more traffic were concentrated on the urban freeway interchange in the inbound direction when compared with the outbound direction.
iv) The delay predictive models showed a higher explanatory power in the inbound direction and the daytime period, but a lower explanatory power in the outbound direction and the nighttime period.
v) The urban freeway traffic management system(UFTMS) measure like the variable message sign(VMS) was shown to be more effective on the inbound exit ramp in the morning rush hour.목차
ABSTRACT = i
NOMENCLATURE = v
LIST OF FIGURES = vi
LIST OF TABLES = viii
1. 서론 = 1
1.1 연구 배경 = 1
1.2 연구 목적 및 필요성 = 1
1.3 문헌조사 = 2
1.4 연구내용 및 방법 = 4
2. 교통 특성 분석 = 5
2.1 교통류율 = 6
2.2 속도 = 14
2.3 점유율 = 20
2.4 지체 = 26
2.5 교통류율과 속도 = 30
3. 모형 구축 = 31
3.1 구축 방법 = 31
3.2 모형 구축 = 32
4. 모형 검증 = 35
4.1 검증 방법 = 35
4.2 모형 검증 = 35
5. 결론 및 향후 연구과제 = 41
참고문헌 = 4
Combustion Characteristics and Durability of Diesel Engine Utilizing Emulsified Fuel
Get PDFThis study is carried out to investigate the combustion characteristics and durability of a diesel engine utilizing emulsified fuel. Recently, air pollution from the vehicle is one of the most serious problem . NOx, PM and sfc reduction is further required in diesel engines. In this study, for the reduction of harmful emissions, W/O(water in oil) type emulsified fuels with 13%, 15%, 17% water are used. Piezo-electric pressure sensor is used to get combustion pressure in cylinder and exhaust gas analyzer is used to measure exhaust emissions. Specific fuel consumption, sound level, and maximum torque are also measured.
It was ascertained that the results show the 15% water emulsified fuel is good for NOx and PM reduction simultaneously and does not have much effect on a fuel consumption and a durability.목차
List of Tables = iii
List of figures = iv
ABSTRACT = viii
I. 序論
1.1 연구배경 = 1
1.2 선행연구 = 2
1.3 연구목표 = 5
II. 理論的 考察
2.1 에멀션연료(Emulsified fuel) = 6
2.1.1 에멀션연료의 연소특성 = 8
2.1.2 에멀션연료의 미세폭발(Micro-explosion) = 10
2.1.3 해외 에멀션연료 개발현황 = 10
III. 實驗裝置 및 方法
3.1 D-13 모드 기관내구실험 및 배기가스 측정 = 12
3.1.1 실험장치 = 12
3.1.2 실험방법 = 16
3.2 연소실 압력측정 = 18
3.2.1 실험장치 = 18
3.2.2 실험방법 = 20
3.3 노즐 연료 분사량 = 20
3.3.1 실험장치 = 20
3.3.2 실험방법 = 23
3.4 에멀션연료의 제조 = 23
IV. 實驗結果 및 考察
4.1 D-13 모드 기관내구실험 = 26
4.2 D-13 모드 기관 배기가스 = 37
4.3 연소압력 측정 = 46
4.4 연료노즐 연료분사량 측정 및 기관소음측정 = 62
V. 結論 = 64
參考文獻 = 6
(A) Study on the Successful Operation of Annual Salary System in Korean Companies : Focus on Case Analysis
Get PDFThe environment of business management is rapidly changing as the survival of the fittest is becoming a principle amid internationalization, globalization and openness. Under this circumstance of indefinite competition, businesses are absolutely needed to change wage payment system under the seniority rule to annual salary system. Recently more and more local companies have introduced annual system in which compensation is determined according to each worker's capability and accomplishment, becoming a greatly changing blow to the existing payment system under the seniority rule. Annual salary system intends to promote employees' desire for work, increase productivity and innovate organizational climate by adding a motivational factor to the traditional salary system of local businesses under which longer service is rewarded with more payment.
Thus the purpose of this study is to offer effective ways of introducing annual salary system to domestic companies and build up annual salary system ideal to this nation's circumstances by providing a basic concept of the system and reviewing the current situation and cases of the system instruction in this nation.
The current situation of introducing by domestic companies of annual salary system can be summarized as follows.
First, many companies of Korea have already adapted annual salary system as an capability-oriented reward method to motivate workers.
Second, many businesses have introduced annual salary system focusing on managerial positions, which have been found more effective.
Third, annual salary system has raised workers' participatory motivation and made clear their perception of working objectives, ultimately positively influencing workers' motives for their duties.
Fourth, in its initial stage, annual salary system has been found not having better effects of increasing the ability of individual performance and improving organizational climate.
Desirable ways of introducing annual salary system can be suggested as follows.
First, the capability, accomplishment and attitude of each worker should be evaluated objectively and fairly in advance to establish annual salary system. As a reward method based on capability, annual salary system should take the objective and fair evaluation as its precondition. In particular, conventional complaints about the existing merit rating system should be solved to achieve positive effects of the annual payment system.
Second, in its initial stage, annual salary system should be applied to provoke competition among workers within the same level. In this case, payments under the system should be different one another only within 5 to 10 %. After annual salary system is established considerably, it is desirable to expand such difference and promote completion among different levels.
Third, annual salary system should be introduced first focusing on managerial and expert positions.
Fourth, payment under annual salary system should be divided into 16 segments. That is, a sixteenth of the total amount should be paid every month over a year, The remaining four sixteenths should be given to workers every quarter in the form of bonus. This can avoid adverse effects of the system introduction.
Prior to the introduction of annual salary system, companies should determine whether they will pay a basic annual salary or add incentives to it. It is recommended to seriously consider the latter to maximize workers' motives.
The original Western annual salary system is in fact far away from this nation's business climates and workers' emotions because it does not allow bonus and benefits as well as retirement grants.
From the view of Korean people, annual salary system should be based on payment system under the seniority rule as long familiar to businesses and workers, and thereon partly added with the capability-based salary system in which workers are differently paid according to their capabilities and accomplishments.
Then the latter system should be expanded ultimately toward the original Western system. In conclusion, annual salary system currently operated in Korea is sort of compromise between the existing payment system under the superiority rule and the original salary system.Abstract = Ⅵ
제 1 장 서론 = 1
제 1 절 문제제기 = 1
제 2 절 연구목적 = 3
제 3 절 연구의 범위 및 방법 = 6
제 2 장 연봉제의 이론적 고찰 = 8
제 1 절 연봉제 = 8
1. 연봉제의 개념 = 8
2. 연봉제의 성격 = 10
3. 연봉제의 유형 = 11
제 2 절 연봉제의 도입배경 = 12
1. 국제적 요인 = 14
2. 국내적 요인 = 14
3. 도입유형 = 17
제 3 절 연봉제의 특징 및 장·단점 = 18
1. 특징 = 18
2. 연봉제의 장점 = 19
3. 연봉제의 단점 = 21
제 4 절 외국의 연봉제도 = 22
1. 미국의 연봉제도 = 22
2. 일본의 연봉제도 = 31
3. 독일의 연봉제도 = 40
？？ 3 장 연봉제 도입기업의 사례분석 = 47
제 1 절 연봉제의 국내 동향 = 47
1. 국내기업들의 연봉제 실시현황 = 47
2. 연봉제를 위한 평가제도의 현황 = 50
제 2 절 두산그룹의 능력급제 = 51
1. 능력급제의 도입배경 = 51
2. 능력급제의 운영 = 53
3. 두산그룹의 능력급제의 특징 = 56
4. 현행 능력급제의 과제와 개선방향 = 57
제 3 절 대상그룹의 연봉제 = 58
1. 신인사제도의 도입배경과 접근방법 = 58
2. 신인사제도의 체계와 운영방법 = 60
3. 연봉제의 운영 = 61
4. 대상그룹의 특징 = 61
5. 현행 연봉제의 과제와 향후 개선 방향 = 63
제 4 절 태평양의 연봉제도 = 63
1. 연봉제의 도입배경과 준비작업 = 63
2. 연봉제의 내용과 운영방안 = 64
3. 태평양 연봉제의 특징 = 66
4. 연봉제 실시의 효과와 향후 운영방안 = 67
제 5 절 삼양사의 연봉제 = 68
제 6 절 (주)한글과 컴퓨터 연봉제 = 68
1. (주)한글과 컴퓨터 연봉제실시 현황 = 69
2. 연봉제의 급여체계 = 69
제 7 절 LG 화재해상보험 = 71
1. 연봉제 도입의 배경 = 71
2. 연봉제의 ？乍㈒섟？ = 73
제 8 절 연봉제 도입사례의 특징 = 74
제 9 절 연봉제 도입 전·후의 매출액 증감 = 76
제 4 장 연봉제의 성공적 운영방안 = 78
제 1 절 기본방향 = 78
제 2 절 합리적 연봉제 운영방안 = 79
1. 적용범위 결정 = 79
2. 현행 급여체계의 연봉액 조정방안 = 80
3. 연봉제의 임금지급방법 = 81
4. 연봉조정 방법 = 81
5. 연봉제를 위한 평가제도 확립 = 82
제 3 절 연봉제 운영에 따른 예상문제점 = 82
1. 근로계약기간에 따른 문제점 = 82
2. 연봉제 적용범위에 따른 문제점 = 83
3. 근로계약 체결상의 고려사항 = 84
4. 할증 임금의 지급유무 = 84
제 4 절 연봉제와 노동법의 조화방법 = 85
제 5 절 한국형 연봉제 = 87
제 5 장 결론 = 89
참고문헌 = 9
Design and Cost Estimation for Pressure Vessels in the Web based Environment
Get PDFInternet service has now become available to anyone who has a personal computer and as more computer networks have been built. One can take advantages of the internet anywhere and anytime. Many web sites have been built according to personal needs, for example, personal homepages, on-line newspapers, search sites etc. Besides, many web users who are attracted by engineering calculation have studied to have the calculation and cost estimate done in the web based environment.
So in this study, we have developed a design and cost estimation tool for pressure vessels in the web based environment by using javascript, ASP (Active Server Pages) and MS-SQL (Structured Query Language) database. The tool is based on the ASME Boiler and Pressure Vessel code section VIII Div 1. The execution of engineering calculations is done with javascript. The performance of this program has been verified by both manual calculation and BASIC program. In the near future, many web applications for engineering calculation in the web based environment will become popular.목차
ABSTRACT = iv
제 1장 서론 = 1
1.1 연구 배경 = 1
1.2 연구 동향 = 2
1.3 연구 목적 = 3
1.4 연구 내용 = 4
제 2장 압력용기 설계 이론 = 5
2.1 설계 = 7
2.1.1 기본 사양 = 7
2.1.2 강도 계산 = 9
2.2 재료 구매 = 21
제 3장 웹 기반의 압력용기 설계 = 22
3.1 압력용기 설계 및 견적 시스템 흐름도 = 22
3.2 재질의 물성치 데이터 베이스 구축 = 24
3.3 ASME 코드에 따른 계산식 적용 = 26
3.3.1 요소 값 배열 적용 = 26
3.3.2 압력용기 설계를 위한 입력 폼 구현 = 30
3.4 계산 결과 = 35
3.4.1 계산결과 폼 값 전송 = 35
3.4.2 클라이언？？로 워드 파일 전송 = 36
3.4.3 계산 결과 데이터베이스에 저장 = 38
제 4장 웹 기반의 압력용기 견적 = 40
4.1 재질 두께 형상별 단위가격 데이터베이스 구축 = 40
4.2 새들 치수 데이터베이스 구축 = 42
4.3 견적을 위한 입력 폼 구현 = 44
4.4 견적 결과 = 48
4.4.1 견적 결과 상세 내역 = 48
4.4.2 클라이언트로 워드 파일 전송 = 50
4.4.3 견적 결과 데이터베이스에 저장 = 52
제 5장 결론 및 향후 연구 방향 = 54
5.1 결론 = 54
5.2 향후 연구 방향 = 55
참고문헌 = 5
A Study on the Characteristics of Movement of Sea Water and Water Quality around the Pusan
Get PDFIt is very important to quantitatively assess the movement of sea water before or after constructing shore structures such as breackwaters considering marine environment. This assesment is possible through the use of simulation models designed to predict water movement in a certain area.
In this study, the numerical computations were carried out to predict the sea water movement and quality around the port of Pusan. The computational models adopting ADI Method(Alternating Direction Implicit Method) was already verified from the previous studies, was used here.
And the numerical calculations of pollutant transport in the sea water area were carried out to asses the effect of river inflow.
To achieve this purpose, 4 cases were set as follows1. case 0 : the present condition of river inflow into the sea area,
2. case 1 : 70% of the present condition,
3. case 2 : 50% of the present condition,
4. case 3 : be equipped with sewage treatment works(inflow concentration20 mg/l of COD)
In each case, we could get the result of quantitative analysis. If the sewage treatment works for river discharge is equipped, the sea quality of the area will be more than the present condition.
As a result of this study, much of tidal data around the area could be gained to use the future study and to give the basic materials for the new city plans including the sea area around the city.목차
표목차 = iii
그림목차 = iv
ABSTRACT = v
제1장 서론 = 1
제2장 주변해역의 지리적 특성과 해양환경 = 3
2.1 부산주변해역의 기상 상태 = 3
2.2 기상재해 = 8
2.3 해양수질 = 11
2.3.1 연안해역 등급 및 조사방법 = 11
2.3.2 해양수질 = 14
제3장 해수유동 시뮬레이션 = 23
3.1 실험내용 = 23
3.2 수치모형의 구성 = 23
3.3 수치실험 결과분석 = 31
제4장 해양환경 시뮬레이션 = 34
4.1 오염확산모델 = 34
4.2 수치실험 및 분석 = 36
4.2.1 Case 0(처리되지 않은 생활하수의 유입의 경우) = 37
4.2.2 Case 1(오염부하량을 70%로 경감하였을 경우) = 37
4.2.3 Case 2(오염부하량을 50%로 경감하였을 경우) = 37
4.2.4 Case 3(처리된 생활하수 유입의 경우) = 37
4.2.5 수치실험결과 분석 = 42
제5장 결론 = 43
참고문헌 = 4
A Study on Flow Characteristics around Cooling Tubes of Fan Coil Unit for Marine HVAC system
Get PDFThis experimental study investigates the wake flow behind a pair of cylinders displaced normal to a free stream and the flow characteristics around staggered cooling tube arrays of fan coil unit used in merchant vessel. This study is also aimed to analyze the transition mechanism of the large vortex generating process in the wake having unique vortex shedding pattern associated with the gap difference between the cylinders. The detailed visualization is carried out using the PIV measurement. The transition mechanism of the large generating vortex is clarified by showing the streak lines, the vorticity and the statistical fluctuating velocity distributions.
As for the results of this experimental study, The flow characteristics around cooling tube of fan coil unit are divided into two distinctly areas between the wake behind cylinder. Flow velocity with pressure drop effects is shown according to various Reynolds numbers. Futhermore, the wake of cylinder shows a vortex region with the periodic flow separation due to the wake unsteady phenomena. With increasing air velocity into fan coil unit, heat transfer is also enhanced at evaporator from the temperature measurement.목차
Abstract = iii
NOMENCLATURE = v
1. 서론 = 1
1.1 연구배경 = 1
1.2 관련연구 = 4
제2장 실험장치 및 실험방법 = 7
2.1 실험장치 = 7
2.2 PIV 영상처리 = 11
2.3 원주열후류의 PIV계측 = 15
2.4 유동가시화 = 18
제3장 실험결과 및 고찰 = 21
3.1 피치비에 따른 원주열의 후류특성 = 21
3.2 팬코일주위의 유동특성 = 32
3.2.1 속도분포 = 32
3.2.2 내부유동특성 = 45
3.2.3 열전달 특성 = 57
제4장 결론 = 60
참고문헌 = 6
(A) Study on the investigation and analysis of collisions at sea
Get PDFA Study on the investigation and analysis
of collisions at sea
The collisions at sea among marine casualties are not reduced as the tonnage and speed of ship's increase as well as the traffic quantity increase at sea, in spite of the improvement of nautical equipment, enforcement of crew's education and training as well as improvement of quality standard according to the implementation of ISM code.
The measures to prevent the collisions at sea are simple, and are composed of four stage.:
The first stage is that the officer on duty detect the target from his eye or radar information .
The second stage is determining the type and kind of target-ship.
The third stage is the target trackingenvironmental factor, and company/on board management system and navigator's act. Also described how to investigate and analyze the casual factors.
Even though it was described in this paper how to detect the causal factors and reasons of collisions, and how to analyze the inter-relation of each causal factors, it is necessary to do further study how to analyze the relationship between the liability of concerned parties and the casual factors involved.for example, natural/navigational conditions, crew's human factors, ship's particular, rule or regulation, management system on board, the condition of watch keeping. Therefore the reasons and casualties are so complicated.
This study aims to investigate the collision casualty at sea which needs to clarity all these causal factors of afore-mentioned, and to analyze the causes of problems so as to utilize them to establish the measures of preventing marine accidents.
This study described the concepts of causal factors into three groupscalculation of target speed, course, CPA and TCPA from radar information or visual check.
The fourth stage is determination of vessel in danger after calculation of third stage.
The fifth stage is the judgement of situation if own ship is stand-on or give way vessel according to the 1972 COLREG. The last stage is to carry out proper action according to 1972 COLREG under the circumstances
But by the case, the situations are so different under the different external condition
Research on program for determination of suitable welding condition for the curved block
Get PDFResearch on program for determination
of suitable welding condition for the curved block.
Welding is one of the main processes in a ship construction. Automation of welding is a key work to increase the productivity of the shipbuilding. Welding robots and special automatic welding machines are widely used at the assembly stage for plane block. However, these automatic machines are not used yet for the curved blocks because they contain very complex and continuously changed weld joints. To achieve the automatization of welding for the curved block, an highly intelligent automatic welding system is required. Getting the optimal welding parameters is an important part for the suitable use of this automatic system.
This research aims to do develop a computer program for determination of suitable welding condition for the curved block of a ship hull. In this paper the relationships between welding parameters such as current and voltage, current and deposition rate were investigated through literature survey, theoretical study and the welding experiments. The concept of the critical deposited area and suitable welding current for that area are introduced to get the sound bead at the various inclination of the joint. This area and the current are dependent on the joint inclination and their relationships could be determined by a lot of welding experiments and use of artificial neural network.
Suitable pass number and the other welding parameters could determined by the relationships between the critical area and the welding parameters.
Finally, an algorithm to determine suitable parameter values was developed on the basis of their investigations and realized into a pc program
Research on 3D simulation for Assembly Process of Ship Based on Object-Oriented Information Modeling
Get PDFShipbuilding is a highly integrated technology and belongs to fabrication industry. A ship is a bulky and complex structure and consists of hundreds of thousands of members. It is built by a lot of material processing and fabricating and takes a long term to be completed. The verification of design, schedule plan and production is necessary before beginning of fabrication in order to confirm the optimal fabrication and high productivity. However, it is very difficult to apply this process in the shipbuilding because it is impossible to make a prototype of a ship.
The 3D simulation is a high technology that can realize the entire fabrication processes in the virtual world and verify the highest productivity and best quality of them. Object modeling technique is also an useful tool to implement the shipbuilding process into the computer world.
This paper deals with the 3D simulation of assembly process based on the object oriented information modeling technique. A lot of information of shipbuilding, especially assembly was analysed and modeled in the view point of object oriented modeling technique. This information model was constructed graphically using 3D CAD system, CATIA. On the basis of this graphic model, the assembly process was simulated using 3D simulation system, DELMIA. This 3D simulation recommended optimal assembly process and could show a possibility of the next generation technology of shipbuilding.목차
Abstract = ii
List of Figures = iii
제 1 장 서론 = 1
제 2 장 Simulation Based Manufacturing = 3
2.1 Simulation Based Design = 3
2.2 Simulation Based Manufacturing = 4
2.3 시뮬레이션 기반 생산의 요소기술 = 5
2.4 SBD시스템의 프레임웍 = 7
2.5 Modeling & Simulation (M&S) = 9
2.6 가상 프로토타이핑 기술 = 9
2.7 모델링 및 시뮬레이션 기술의 적용 = 10
제 3 장 객체 지향 모델링 기법 = 12
3.1 데이터베이스의 개요 = 12
3.2 객체와 클래스 = 14
3.3 클래스의 상관관계 = 16
3.4 객체 모델링 기법의 장점 및 단점 = 21
3.5 객체의 모델링 = 24
제 4 장 선박조립공정의 분석 및 모델링 = 28
4.1 개요 = 28
4.2 공정분석 = 29
4.3 시스템 설계 = 30
4.4 객체 모델링 = 31
제 5 장 선박조립공정의 3차원 시뮬레이션 구현 = 34
5.1 그래픽 사용자 인터페이스 = 34
5.2 선박조립공정의 구현 예 = 39
제 6 장 결론 = 46
참고문헌 = 4
Deposition of ITO Thin Film at Low-Temperature by Inclination Opposite Target Type DC Magnetron Sputtering Method
Get PDFThe In₂O₃-SnO₂, ITO, thin film is a transparent conductive film. And the ITO film is one of the materials for widely practical usage in the optical electron field.. Because the ITO film has high transparency in visible spectral region and low electrical resistivity, it has excellent electromagnetic shielding effectiveness. In this study, the ITO film was prepared onto plastic film substrate at room temperature by the inclination opposite target type DC magnetron sputtering equipment, in which a metallic indium tin alloy target was used . The effects of oxygen gas flow rate and bias voltage on the electrical resistivity and transparency of the ITO film were discussed. For low electrical resistivity of the ITO film, the electromagnetic shielding effectiveness was studied. The results obtained were as follows:
(1)The ITO film produced at room temperature had amorphous structure with very smooth surface.
(2)The electrical resistivity of ITO film deposited at room temperature showed minimum value at the oxygen gas flow rate of 0.4sccm.
(3)The electrical resistivity of ITO film deposited at room temperature depended on the bias voltage and showed the minimum value in the bias voltage of -70V
(5)When the bias voltage was -70V, the ITO film deposited at room temperature showed the most electromagnetic shielding effectiveness (21dB)목차
ABSTRACT
제1장 서론 = 1
제2장 기본 이론 = 3
2.1 투명 전도막의 기초적 성질 = 3
2.2 투명 전도막의 전기적 성질 = 6
2.3 투명 전도막의 광학적 성질 = 10
2.4 투명 전도성 재료의 제조 방법 = 12
2.5 전자파의 개요 및 차폐관련 표면 처리 기술 = 15
2.5.1 전자파의 개요 및 차폐 = 15
2.5.2 차폐관련 표면 처리 기술 = 21
2.6 아몰퍼스의 정의, 분류 및 제작 방법 = 23
2.7 ITO막제작을 위한In 및 Sn의 물성 = 25
2.7.1 In의 물성 = 25
2.7.2 주석(Sn)의 물성 = 26
제3장 실험 방법 = 28
3.1 ITO 박막의 제작 = 28
3.1.1 실험 장치 = 28
3.1.2 실험 재료 = 29
3.1.3 박막 제작 방법 = 32
3.2 ITO 박막의 특성 분석 및 평가 = 34
3.2.1 박막의 결정 구조 분석 = 34
3.2.2 표면의 몰포로지 관찰 = 34
3.2.3 박막의 두께 측정 = 35
3.2.4 ？美렝？ 전기 비저항 측정 = 36
3.2.5 박막의 투과율 측정 = 37
3.2.6 박막의 전자파 측정 = 39
3.2.6.1 TRI17302 실드 평가기 = 39
3.2.6.2 스펙트럼 분석기 = 41
제4장 결과 및 고찰 = 42
4.1 저온 중 산소변화량에 의한 막의 특성변화 = 42
4.2 저온 중 이온충격에 의한 막의 특성 변화 = 47
4.3 저온에서 제작한 막의 기판위치에 따른 저항률변화 = 53
4.4 저온에서 제작한 막의 차폐효과 = 56
제5장 결론 = 59
참고문헌 = 6