229 research outputs found
두부계측방사선 사진 계측점 자동 식별의 최신 기계 학습 알고리즘 간 정확도 및 연산 성능 비교 연구 – YOLOv3 vs SSD
학위논문(박사)--서울대학교 대학원 :치의학대학원 치의학과,2019. 8. 이신재.Introduction: The purpose of this study was to compare two of the latest deep learning algorithms for automatic identification of cephalometric landmarks in their accuracy and computational efficiency. This study uses two different algorithms for automated cephalometric landmark identification with an extended number of landmarks: 1) You-Only-Look-Once version 3 (YOLOv3) based method with modification, and 2) the Single Shot Detector (SSD) based method.
Materials and methods: A total of 1,028 cephalometric radiographic images were selected as learning data that trained YOLOv3 and SSD methods. The number of target labelling was 80 landmarks. After the deep learning process, the algorithms were tested using a new test data set comprised of 283 images. The accuracy was determined by measuring the mean point-to-point error, success detection rate (SDR), and visualized by drawing 2-dimensional scattergrams. Computational time of both algorithms were also recorded.
Results: YOLOv3 algorithm outperformed SSD in accuracy for 38/80 landmarks. The other 42/80 landmarks did not show a statistically significant difference between YOLOv3 and SSD. Error plots of YOLOv3 showed not only a smaller error range, but also a more isotropic tendency. Mean computational time spent per image was 0.05 seconds and 2.89 seconds for YOLOv3 and SSD, respectively. YOLOv3 showed approximately 5% higher accuracy compared with the top benchmarks in the literature.
Conclusions: Between the two algorithms applied, YOLOv3 seems to be promising as a fully automated cephalometric landmark identification system for use in clinical practice.연구 목적: 본 연구의 목적은 두부계측방사선 사진 계측점 자동 식별에 있어, 최근 개발된 두 가지 딥 러닝 알고리즘의 정확도와 연산 성능을 비교하는 것이다. 본 연구에서는 다음 두 가지의 알고리즘을 계측점 자동 식별에 적용하였다. 1) You-Only-Look-Once version 3 (YOLOv3) 및 2) the Single Shot Detector (SSD).
재료 및 방법: 총 1,028 개의 두부계측방사선 사진 영상이 YOLOv3 와 SSD방식의 학습 데이터로 사용되었다. 대상 계측점은 80개였다. 학습 과정을 거친 후, 각각의 알고리즘을 새로운 283 개의 테스트 영상에서 비교 분석하였다. 정확도는 1) 평균적인 point-to-point error, 2) success detection rate (SDR), 그리고 3) 2차원 평면에서 시각화한 scattergram 을 기반으로 평가했다. 각각의 알고리즘의 평균 연산 시간 역시 기록하였다.
결과: YOLOv3 는 SSD 에 비해 총 38/80 개의 계측점에서 더 높은 정확도를 보였다. 나머지 42/80 개의 계측점은 두 알고리즘 간에 정확도에 있어 통계적으로 유의미한 차이를 나타내지 않았다. Error plot 에서는 YOLOv3 가 SSD 에 비해서 error 의 범위가 더 작을 뿐 아니라, 2차원 평면에서 방향성의 영향을 덜 받는 것으로 나타났다. 하나의 영상에서 계측점을 자동 식별하는데 소요된 평균 시간은 YOLOv3 와 SSD 가 각각 0.05 초, 2.89 초로 기록되었다. 본 연구에서 YOLOv3 는 기존 문헌에서 최상의 정확도를 기록했던 연구에 비해 약 5% 가량 높은 정확도를 보였다.
결론: 본 연구를 통해 적용된 두 개의 알고리즘 중, YOLOv3 가 두부계측방사선 사진 계측점 완전 자동 식별의 임상적인 적용에 가능성 높은 알고리즘임을 확인하였다.Abstract
Contents
I. INTRODUCTION 1
II. MATERIALS AND METHODS 4
1. Subjects 4
2. Manual identification of cephalometric landmarks 4
3. Two Deep Learning Systems 5
4. Test Procedures and Comparisons between the two systems 6
III. RESULTS 7
IV. DISCUSSION 8
V. CONCLUSIONS 13
REFERENCES 14
TABLES 20
FIGURES 24
국문초록 46Docto
컬러 카메라 이미징 뮬러 행렬 엡립소미터를 이용한 영역 분류와 박막 두께 측정에 관한 연구
학위논문 (석사)-- 서울대학교 대학원 : 공과대학 기계항공공학부, 2019. 2. 박희재.타원계는 광학 측정 방식으로 반도체, 디스플레이 공정 검사에서
비접촉, 비파괴, 신속 측정이 가능한 장점이 있다. 분광 방식의 경우
높은 파장 해상력을 통해 높은 정밀도를 얻을 수 있다는 장점이 있으나,
단일 영역 측정 한계와 좁은 영역의 측정이 불가능하며 측정 영역 내의
모호성 문제가 있다. 2D CCD를 이용한 이미징 방식의 측정 방법은 공간
해상력을 픽셀 수준까지 높일 수 있어 많은 연구가 진행되었다. 기존의
단파장 이미징 방식은 파장 데이터의 부족으로 측정 모호성이 있으며,
다파장 이미징 방식의 경우 파장을 바꾸는 과정으로 인해 측정 시간이
길다는 한계가 있다. 이에 본 연구에서는 컬러 카메라를 이용한 이미징
뮬러 행렬 타원계를 이용하여 문제를 해결한다. 추가적으로 이미징
방식의 경우 이미지 영역 전체 픽셀 분석의 경우 많은 시간이 걸려
불가능한 문제가 있다. 이 문제를 제안하는 클러스터링 방식을 사용하여
해결하고자 한다.
연구에 사용되는 컬러 카메라는 베이어 필터로 인해 여러 파장의 뮬러
행렬이 중첩된 결과가 측정되게 된다. 따라서 광대역 파장 필터에
적용할 수 있는 필터의 투과도를 고려한 새로운 뮬러 행렬 식을
제안한다. 제안한 방식을 이용하여 두께 측정을 진행하고, 검증된
하드웨어로 측정된 결과와 비교하여 검증하였다.
연구에 사용된 클러스터링 방법을 통해 이미지 영역을 비슷한 뮬러
행렬을 갖는 영역끼리 분류하였고, 분류한 영역의 평균 두께를
측정하였다. 각 클러스터 내의 표준편차를 확인하여 평균값이
클러스터를 대표할 수 있음을 확인하였다.The ellipsometer, one of the optical measurement systems, are
widely used because of the advantages of non-contact, nondestructive and rapid measurement. the spectroscopic method has
the superiority of high precision because of high wavelength
resolution, but the system can not measure narrow areas and has
ambiguity in the measurement area and a limit for measuring only a
single area. Imaging systems using 2D CCD are a technique to
increase spatial resolution to pixel levels. Traditional
monochromatic imaging methods have uncertainty in measurement
because of the lack of wavelength data, and multi-wavelength
imaging methods have long measurement time due to wavelength
changes. In this study, A color camera imaging Mueller matrix
ellipsometer is proposed to solve the problem. Further, imaging
methods have a problem that takes a long time to analyze the entire
pixel of an image, and a clustering method is proposed to solve the
analysis time problem.
The measured data with the color camera is the result of a
superposition of different wavelengths due to the Bayer filter.
Therefore, a new Mueller matrix equation is proposed considering
the transmittance of the filter that can be applied to a broadband
wavelength filter. Thickness measurements were implemented
using the proposed method and verified by comparing with the
measured results with validated hardware.
Through the clustering method used in the study, the image was
classified into regions having similar Mueller matrices, and the
average thicknesses of each class were measured. By examining
the standard deviation within each cluster, we have verified that the
mean of the Mueller matrix of the class can represent the classChapter 1. Introduction 1
1.1 Research background. 1
1.2 Research Trends 2
1.2.1 Mueller matrix ellipsometry 2
1.2.2 Imaging reflectometry. 3
1.2.3 Imaging ellipsometry . 4
1.3 Research topic 5
Chapter 2. Theoretical Background. 7
2.1 Research background. 7
2.1.1 The law of refraction and reflection. 7
2.1.2 Multiplt reflections in thin-film 8
2.2 Jones and Mueller matrix. 9
2.3 Mueller matrix ellipsometry 10
2.3.1 Ellipsometry configuration 10
2.3.2 MME parts 12
2.3.3 Decomposition 13
2.4 Clustering 14
2.4.1 Principal component analysis 14
2.4.2 K-means clustering 16
Chapter 3. Data Acquisition Method 17
3.1 Beam drifting correction 17
3.2 Mueller matrix calculation . 17
3.3 Calibration. 18
3.4 Mueller matrix decomposition . 20
3.5 Mueller matrix in a RGB color space 21
3.6 Thickness measurement 22
3.7 Clustering 23
Chapter 4. Result. 27
4.1 Measurement sample . 27
4.2 Classification and thickness measurement . 28
Chapter 5. Conclusion 30
Bibliography. 31
Abstract in Korean 34Maste
Analysis Technology Development of Cause Investigation for Ship Collision⋅Grounding Accident
최근 대용량의 전산시스템의 개발과 더불어 LS-DYNA 코드와 같은 고도 비선형 동적 상용해석 프로그램이 크게 발전됨에 따라 구조 안전성 평가를 위한 내충격 응답해석 기법이 매우 활발히 수행되고 있으며 실험이나 시험을 보조하거나 대체할 수 있는 단계에 있다. 폭발, 슬로싱, 충돌, 좌초, 전복, 침수 및 침몰 등과 같이 유체와 관련된 내충격 응답을 정확하고 합리적으로 수행하기 위해서는 유체-구조 연성 해석기법의 고도 정밀 M&S 시스템을 이용한 실선 시뮬레이션을 수행하는 것이 가장 최선의 접근 방법이라 할 수 있다.
이러한 유체-구조 연성 해석기법의 고도 정밀 M&S 시스템은 해수에서 선박이 부양(floating)되고, 6자유도의 운동(motion)도 하고, 선내에 해수도 침수(flooding)되고, 운항 중일 때 파도(wave)도 생성하고, 두 물체가 근접할 경우에는 압착압력(squeezing pressure)이 발생하고, 두 물체가 스쳐 지나거나 안벽과 해저에 근접하게 운항할 경우에는 압력이 저하(banking effect)되는 등 해수에서의 여러 가지 연성효과를 구현할 수 있다. 손상자료를 세심히 분석하면서 충돌속도에 따른 변형률 의존 재료 물성치를 고려하는 파단모델을 합리적으로 구조 손상을 구현하는 것도 중요하다.
본 논문에서는 소형 어선의 충돌사고의 원인분석과 방사성폐기물 운반선의 좌초에 대한 구조 안전성 평가를 위해 유체-구조 연성 해석기법의 고도 정밀 M&S 시스템을 이용한 실선 충돌 및 좌초 시뮬레이션을 수행하였으며, 해수 중에서 보다 정확하고 실제적인 충돌 및 좌초 거동과 손상 응답을 구현할 수 있었다.
|With the advent and ongoing advances in numerical simulation capabilities and its sophisticated tools, such as highly accurate dynamic nonlinear simulation hydrocode LS-DYNA, development of shock response analysis techniques has been actively carried out for the structural safety assessment with viable, less costly alternatives as well as more reliable aids to the tests and/or experiments. To ensure an accurate and reasonable prediction of shock response with relation to the fluid, such as explosion, sloshing, collision, grounding, capsize, flooding and sinking etc., full-scale simulations would be the best approach using highly advanced M&S (Modeling & Simulation) of its Fluid-Structure Interaction (FSI) analysis technique.
Several coupling effects in the water could be conceptualized in this highly advanced M&S system of FSI analysis technique, such as floating, motion, wave making, squeezing pressure, bank effect and realistic ship velocity. Fracture criteria have to be also suitably applied to the structural damage considering strain rate effect, together with careful investigation of damage information.
In this study, using highly advanced M&S system of FSI analysis technique, full-scale ship collision & grounding simulations were performed for the investigation of small fishing ship collision and capsize accident and for the structural safety assessment of radioactive waste matter carrying vessel. More accurate and realistic collision and grounding behaviors, damage responses could be found in water condition using highly advanced M&S system of FSI analysis technique.1. 서 론 1
2. 선박 재료의 파단기준 7
3. 충돌사고의 원인규명 시뮬레이션 기법 11
4. 좌초사고의 구조 안전성 평가 시뮬레이션 기법 23
5. 고찰 및 결론 32
Reference 34
감사의 글 35Maste
A Study on the Design of Hybrid Energy Storage System combined by Pumped Hydro Storage and Compressed Air Energy Storage Technology
Storing energy is important since electricity should be available whenever needed and must be used or stored immediately after being generated. Many renewable energy technologies such as solar and wind energy, provide intermittent power generation and sometimes produce surplus electricity when demand is low. Current growth of renewable energy systems are subjected to the issues of higher costs and power instability which makes energy storage systems essential.
This research work focuses on a mechanical hybrid energy storage system which uses the concepts of combined pumped hydro storage (PHS) and compressed air energy storage (CAES). The system consists of one open tank to the air and one closed tank which stores water and compressed air. The multistage pump and hydro turbine are used for the charging and discharging process respectively, similar to pumped hydro storage operation in hydropower plants. When the grid power is at surplus, the unused power can be utilized to operate the multistage pump and store water and compressed air in the pressure vessel. The energy of compressed air can be released to drive water which passes through the hydro turbine, resulting in the generation of electricity when the grid power is insufficient. A major disadvantage of the conventional PHS and CAES is that the site where the systems can be installed is rare and have environmental side effects. As an alternative, this energy storage system is capable of overcoming the difficulties posed by PHS and CAES. This system can be used regardless of site conditions, since it uses a pressure vessel instead of two reservoirs of pumped hydro storage.
This study was carried out to verify the operating principle and analyze the characteristics of energy charging and discharging of the mechanical hybrid energy storage system. Firstly, the characteristics of energy charging and discharging of lab-scale model was analyzed and additionally CFD analysis and experimental test were performed on the charging and discharging process. It was found that the pressure in the vessel depends only on stored volume and air compression ratio of water at isothermal state without the loss to outside. Therefore, it is more effective to control the discharging flow rate from the pressure vessel in the operation. Secondly, the characteristics study of the charging process by multistage pump depends on variable speed which was carried out. In addition, a numerical model of the multistage pump was made and analysed using CFD and the performance and characteristics of the pump were determined and plotted. By using the plotted data and related formulas, a more efficient charging process by pump operation was found. In this thesis, the submerged floating-type mechanical hybrid energy storage system that can minimize the pressure differences between inside and outside of pressure vessel, by installing it in the sea was suggested. The submerged floating-type mechanical hybrid energy storage system has advantages such as the size reduction of pressure vessel and ensuring stability of the pressure vessel. Regardless, it should be further investigated for stability of mooring line considering effect of ocean current.1. 서 론 1
1.1 연구배경 1
1.2 연구목적 3
1.3 에너지 저장 기술의 개요와 설치 사례 4
1.3.1 양수발전 3
1.3.2 압축공기에너지저장 6
1.3.3 플라이휠 에너지 저장장치 8
1.3.4 납축전지 10
1.3.5 Nas전지 12
1.3.6 리튬전지 14
1.3.7 흐름전지 18
1.3.8 ESS의 기술별 특성과 적용분야 21
2. 기계적 Hybrid 에너지 저장 장치 24
2.1 장치의 구조 및 개념 24
2.2 에너지 저장 용량에 따른 압력용기의 크기 결정 27
2.3 펌프의 선정 29
2.4 수차의 선정 32
3. 기계적 Hybrid ESS의 Lab-scale 모델 수치해석 34
3.1 수치해석 기법 34
3.1.1 지배방정식 35
3.1.2 이산화방법 36
3.1.3 난류모델링 39
3.2 에너지 저장에 따른 압력용기의 내부 유동장 분석 41
3.2.1 3D형상 및 격자 41
3.2.2 경계조건 41
3.2.3 내부 유동장 분석결과 44
3.3 에너지 방출에 따른 압력용기의 내부 유동장 분석 51
3.3.1 3D형상 및 격자 51
3.3.2 경계조건 51
3.3.3 내부 유동장 분석결과 53
3.4 에너지 저장용 펌프의 성능해석 66
3.4.1 3D형상 및 격자 66
3.4.2 경계조건 66
3.4.3 성능해석결과 69
3.4.4 에너지 저장 과정에서의 에너지 소모량 비교 72
4. 기계적 Hybrid ESS의 Lab-scale 모델실험 76
4.1 실험장치 76
4.2 계측시스템 76
4.3 실험결과 79
5. 수중부유식 기계적 Hybrid ESS 83
5.1 장치의 구조와 개념 83
5.2 위치하는 수심 변화에 따른 압력용기의 크기 추산 86
6. 결론 90
참고문헌 92Docto
Uncertainty Quantification of Reservoir Performances Using Streamline Based Inversion and Distance Based Method
학위논문 (석사)-- 서울대학교 대학원 : 에너지시스템공학부, 2014. 2. 최종근.For decision makings, it is crucial to have proper reservoir characterization and uncertainty assessment of reservoir performances. Since an initial model constructed with limited data has high uncertainty, it is essential to integrate both static and dynamic data for reliable prediction. Uncertainty quantification is computationally demanding because it requires a lot of iterative forward simulations and optimizations in a single history matching. Multiple realizations of reservoir models should be history matched. In addition, history matching is mathematically a highly ill-posed problem.
In this paper, a methodology is proposed to rapidly quantify uncertainties by combining streamline based inversion and distance based method. First, a distance between each model is defined as the norm of differences in generalized travel time vectors. Second, they are grouped according to distances and representative models are selected instead of matching all models. Third, generalized travel time inversion is applied for integration of dynamic data and a streamline simulator is adopted as a forward simulator to take advantage of computational efficiency. It is verified that the proposed method gathers models with similar dynamic responses and permeability distribution. It also assesses the uncertainty of reservoir performances fairly well, while reducing the amount of calculations significantly by using the representative models.Abstract ⅰ
Table of Contents ⅱ
List of Tables ⅲ
List of Figures ⅳ
1. Introduction 1
2. Theoretical backgrounds 7
2.1 Streamline simulation 7
2.2 Generalized travel time inversion 14
2.3 Distance based method 25
2.4 Randomized maximum likelihood 28
3. Quantifying uncertainty with GTTI, RML, and distance based method 30
4. Results 35
4.1 Reference field 35
4.2 Sensitivity calculations 43
4.3 Application of distance based method, RML and GTTI 46
4.4 Misfit reduction and improvement of computational efficiency 73
5. Conclusions 76
References 78
국문초록 84Maste
A Study on the Activation of Integrated Freight Information Network in the Cargo Transportation
4차 산업혁명과 전자상거래 확산으로 인한 전통적 시장구조 변경이라는 환경변화에도 불구하고 화물자동차 운송시장의 구조적 문제점인 지입제도, 다단계 운송거래로 인하여 물류 환경변화를 화물자동차 운송시장 발전의 전환점으로 살리지 못하고 있다. 이러한 환경변화에 대응하여 정부도 물류 산업혁신방안을 발표하였다. 주요 내용은 시장질서 혁신방안으로 지입제도 폐지 검토, 다단계 운송 제한을 위한 직접운송의무비율 상향과 화물정보망 활성화를 위한 운송가맹점 차량 허가 대수 기준 완화, 물류 정보화 사업 투자이다.
본 연구의 목적은 화물자동차 운송시장의 구조적 문제 해결을 위해 화물정보망이라는 제도를 도입하였으나 아직 활성화가 부족한 현실이다. 화물자동차 운송시장의 선진화 방안으로 화물정보망을 도입하였음에도 활성화되지 못한 한계점을 알아보고자 하였다. 또한, 현재 운영되고 있는 화물정보망의 사례 연구를 통하여 특징 및 한계점을 분석하고 최근 물류기술 동향, 화물자동차운송시장 특성 및 정부의 정책 방향을 고려한 화물정보 통합망 활성화 방안을 제시하는 것이 본 연구의 목적이다.
연구방법으로는 통계자료를 통한 화물자동차 운송시장의 특성과 문제점을 도출하고, 시사점을 통한 화물정보망의 필요성에 관하여 연구하였으며, 화물정보망 사업자에 대한 사례분석을 통하여 기존 화물정보망의 특징 및 한계점을 연구하였다.
통계자료로 확인한 직접운송경로는 42.4%로 절반에 미치지 못하고 있으며 실제로 주선사 간의 거래는 직접운송의무 단계에서 제외된다는 점을 고려하면 통계치는 더욱 낮다. 이러한 거래단계 증가는 운송서비스 품질 저하, 운송업체의 경영악화로 이어지고 있다.
화물정보망 사업자의 사례 연구를 통한 화물정보망은 개방형과 폐쇄형으로 구분할 수 있고 이러한 개방형은 비수익형과 수익형으로 구분할 수 있으며, 화물정보망 시장의 한계점은 화물정보망 사업자의 물량확보가 미흡하고, 수수료 수익 위주의 획일화된 플랫폼에 있다. 또한, 정부의 정책 또한 실적신고, 정보망 인증에 그쳐 정책 자체가 미흡하다고 볼 수 있다.
본연구에서 제안하는 화물정보 통합망의 추진방안은 1단계 물류기술 동향반영, 2단계 정부 물류 선진화 정책 반영, 3단계 영세차주 지원, 4단계 개방형 연계, 5단계 정부 기관과 금융기관 연계되어야 하며 기존 정보망과는 달리 화주, 운송 주선업체, 물류 센터, 화물차주뿐만 아니라 정보망사업자, 정부 기관이 통합된 시스템으로서 화물정보 통합망 형태로 제안하고자 한다.
본연구의 결과 앞으로의 화물정보망은 화물정보 통합망 형태로 구현되어야 하며, 비수익형 정보제공형인 화물복지재단의 시스템과 연계하면 신규 개발에 필요한 하드웨어 및 인프라 비용을 절감할 수 있으며, 정보망 참여를 위하여 의무가입 정책 또는 참여 거래업체에 대한 성과보수 제도가 필요하다. 이러한 화물정보 통합망을 이용하게 되면 화물 운송의 빅데이터를 활용하여 공차 감소를 위한 최적 경로 도출 및 화물 운송과 관련된 추가정보 등을 확보할 수 있다.
본연구의 한계점으로는 시스템 도입에 따른 사회적 비용 절감과 경영수지 개선 효과에 관한 연구는 수행하지 못하였다. 그리고 향후 화물정보 통합망 도입의 영향력에 관한 연구가 필요할 것이다.
|Despite the environmental change of the traditional market structure caused by the 4th industrial revolution and the spread of e-commerce, the logistics environment change is not a turning point in the development of the Transportation Industry due to the structural problems of the Transportation Industry and multi-level transportation transactions.
In response to these environmental changes, the government also announced measures to innovate logistics industries. The main contents include consideration of abolishing the land entry system as a means of market order innovation, raising the ratio of direct transport obligations to restrict multistage transport, easing the criteria for the number of license permits issued by the carrier to activate the freight information network, and investing in logistics and information service businesses.
The purpose of this study was to solve structural problems in the Transportation Industry, but the system is still not active. In the preceding research, most of the research related to the freight information network was done as an auxiliary means of government policy and the need for the information network.
It wanted to find out the status of the Transportation Industry and the limitations that could not be activated despite the introduction of the freight information network as a way of advancing the Transportation Industry. In addition, the purpose of this study is to analyze characteristics and limitations through the case study of the currently operating freight information network business model and to present measures to activate the freight information network as implemented by the integrated freight information network system considering the recent trends in logistics technology, characteristics of the freight Transportation Industry and the government's policy direction.
The research method is to draw out the characteristics and problems of the Transportation Industry through statistical data, study the need for the freight information network in the Transportation Industry through implications, study the characteristics and limitations of the existing freight information network through case analysis for the freight information network operators, and propose a joint network model of freight information reflecting improvement plans and changes in logistics environment.
The statistics are even lower, considering that direct transport routes identified by the statistics are less than half the 42.4 percent, and that transactions between the consignors are actually excluded from the direct transport obligation phase. This increase in the level of transactions is leading to poor quality of transportation services and poor management of carriers.
In this study, we proposed ways to utilize the freight information network. By utilizing the freight information network, we can upgrade and streamline transportation services and improve the balance of freight owners by reducing freight forwarding fees by simplifying the middle stage of freight transport transactions.
The freight information network through the case study of the freight information network operators can be divided into open and closed types, and open types can be divided into non-profitable and profitable types.
The limitation of the freight information network market is that the freight information network operators do not secure enough supplies and are on a uniform platform focused on commission revenue. In addition, the government's policies are not enough to report performance and certify the information network.
Therefore, the proposed method of promoting the freight information network is to reflect trends in logistics technology in the first stage, to reflect the government logistics advancement policy in the second stage, to support small car owners in the third stage, to open the fourth stage, and to link the government agencies and financial institutions in the fifth stage.
The information network proposed in this study is a co-network model for integrating freight information. Unlike the existing information network, this concept is a model that integrates not only shippers, transportation agents, logistics centers, and truck owners, but also information network operators and government agencies.
As a result of this study, the future freight information network should be implemented in the form of a shared freight information network, and the non-revenue information provided by the Korea Cargo Welfare Foundation can reduce the hardware and infrastructure costs required for new development.
In order to participate in the information network, the mandatory input policy of the information network or the performance compensation system for the vendors participating in the information network is required. This integrated network enables you to utilize big data from freight transport to derive the optimal route for reducing tolerance and to obtain additional information related to freight transport.
As a limitation of this research, we believe that the impact of introducing the freight information network should be studied, such as the effect of reducing social costs or improving the balance of business, or conflicts of interest between industries.
Key Words : integrated Freight Information Network제 1 장 서 론 1
1.1 연구배경 1
1.2 연구목적 4
1.3 연구내용 및 방법 5
제 2 장 화물자동차 운송시장 현황 연구 7
2.1 화물자동차 운송시장의 산업적 특성 7
2.2 화물자동차 운수사업의 유형 11
제 3 장 화물자동차운송시장의 구조 및 문제점 분석 17
3.1 화물자동차 운송시장의 구조 17
3.2 화물자동차 운송시장 구조상의 문제점 22
3.3 화물 운송시장의 문제점을 통한 시사점 29
제 4 장 화물정보망 일반현황 및 사례분석 31
4.1 화물정보망 일반현황 31
4.2 화물정보망 사업자 사례분석 33
4.3 화물정보망 시장의 특징 및 문제점 43
제 5 장 화물정보 통합망 활성화 방안 46
5.1 화물정보 통합망 구현 및 추진방안 46
5.2 화물정보 통합망 활성화 방안 49
제 6 장 결 론 54
6.1 연구요약 54
6.2 연구의 한계점 및 향후 과제 56
참고문헌 58Maste
The Expression of Programmed Death-Ligand 1 on Immune Cells Is Related to a Better Prognosis in Biliary Tract Cancer
Background/Aims: Programmed death-ligand 1 (PD-L1) expression in tumor cells is associated with a poor biliary tract cancer (BTC) prognosis; tumor-infiltrating immune cells in the tumor microenvironment are associated with a better prognosis. The effect of PD-L1 expression on immune cells on survival is unclear. We investigated the relationship between PD-L1 expression in immune cells and BTC prognosis.
Methods: PD-L1 expression was evaluated using an anti-PD-L1 22C3 mouse monoclonal primary antibody, and its relationships with clinical characteristics and prognosis were analyzed using the Cox proportional hazard model to investigate the prognostic performance of PD-L1 in BTC.
Results: Among 144 analyzed cases, patients with positive PD-L1 expression in tumor cells and negative PD-L1 expression in immune cells showed poorer overall survival rates than those exhibiting other expressions (tumor cells: hazard ratio [HR]=1.023, p<0.001; immune cells: HR=0.983, p=0.021). PD-L1 expression in tumor cells was an independent predictor of poor overall survival (HR=1.024, p<0.001). In contrast, PD-L1 expression in immune cells was a predictive marker of good prognosis (HR=0.983, p=0.018).
Conclusions: PD-L1 expression in immune cells may be used as an independent factor to evaluate the prognosis of patients with BTC. (Gut Liver, Published online December 13, 2022)ope
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