• Title/Summary/Keyword: 발표논문

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An Analysis on the Economic Impacts of the Bio-gas Supply Sector (바이오가스 공급 확대의 경제적 파급효과 분석)

  • Baek, Min-Ji;Kim, Ho-Young;Yoo, Seung-Hoon
    • Journal of Energy Engineering
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    • v.23 no.2
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    • pp.74-82
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    • 2014
  • The government is planning to expand the bio-gas supply as a method for mitigating greenhouse gas emissions to deal with climate change. By means of a policy instrument, the government is considering an introduction of the Renewable Fuel Standard (RFS) whose targets include bio-gas. This paper attempts to look into the economic effects of expanding the bio-gas supply by applying an input-output (I-O) analysis using a 2011 I-O table. The bio-gas supply sector consists of liquefied petroleum gas supply sector and city gas supply sector, based on the tenets of introducing the RFS. The production-inducing effect, value-added creation effect, and employment-inducing effect of the bio-gas sector are analyzed. The supply shortage effect and the price pervasive effect are also investigated. The results show that the production or investment of 1.0 won in the bio-gas supply sector induces the production of 1.0539 won and the value-added of 0.1998 won in the national economy. Moreover, the production or investment of 1.0 billion won, supply shortage of 1.0 won, and a price increase of 10.0% in the bio-gas supply sector touch off the employment of 0.5279 person, 1.6229 won, and an increase in overall price level by 0.0183%, respectively.

Open Techniques for Bone Defect in Anterior Shoulder Instability (골 결손이 동반된 전방 견관절 불안정성에서 개방적 수술 술기)

  • Lee, Bong-Gun;Rhee, Yong-Girl
    • Clinics in Shoulder and Elbow
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    • v.12 no.2
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    • pp.255-263
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    • 2009
  • Purpose: An osseous defect in the glenoid and humeral head is closely associated with recurrence of anterior shoulder instability. The purpose of this article is to describe the open surgical techniques and introduce our experiences with anterior instability with a significant osseous defect. Materials and Methods: We reviewed the articles that have focused on and/or mentioned the affect of osseous defects on anterior shoulder instability. The open surgical techniques and its related pearls are summarized in this review. Results: Accurate evaluation for the size and location of the osseous defect is critical for preventing recurrence after restoration of the anterior capsulolabral structure. The glenoid bone restoration techniques include the coracoids transfer (the Bristow procedure and the Latarjet procedure) and a structural iliac bone graft. Rotational humeral osteotomy and an osteoarticular allograft could be used for repairing a significant posterosuperior humeral defect (Hill-Sachs lesion). Shoulder arthroplasty may be tried for treating a humeral bone defect, but more study on this is needed. Conclusion: Open surgical restoration decreases the risk of recurrence anterior shoulder instability that is combined with a significant osseous defect. Arthroscopic surgery currently has limitations for treating an osseous defect, but it will become useful in proportion to the development of arthroscopic instruments and techniques in the future.

Damage Analysis of Meteorological Disasters for Each District Considering the Characteristics of a District (지자체별 특성을 고려한 자연재해에 따른 피해유형 분석)

  • Jun, Hwan-Don;Park, Moo-Jong;Kim, Guen-Young
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.2
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    • pp.75-82
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    • 2008
  • Heavy rains and typhoons are the most critical meteorological disaster occurred in the Korean peninsular. Due to the global warming, the magnitude of heavy rains and typhoons is becoming heavier resulting in more damage annually. Therefore, it is required to establish a mitigation plan to reduce the damage from meteorological disasters. To do so, in general, it is better to establish a mitigation plan for each district considering the characteristics of a district than a single mitigation plan for the entire districts without considering the characteristics of an individual district. In this study, we provide fundamental data for establishing a mitigation plan from analysis considering the frequency and damage in monetary value by heavy rain and typhoon with the geological and social characteristics of districts. The annual damage reports published by the National Emergency Management Agency, dated from 1994 to 2003, are used for the analysis. The districts are classified into six categories by the geological and social characteristics. Also, the frequency and damage in monetary value are assessed for each district. Based on them, the damage degree by heavy rain and typhoon from 1st to 4th is assigned to each district. The assigned damage degree is, then, analyzed with geological and social characteristics of each district to show the status of damage by meteorological disasters on the district.

Correlationship of the electrical, optical and structural properties of P-doped ZnO films grown by magnetron sputtering (마그네트론 스퍼터링에 의해 phosphorous 도핑된 ZnO 박막의 전기적, 광학적, 구조적 특성의 연관성)

  • Ahn, Cheol-Hyoun;Kim, Young-Yi;Kang, Si-Woo;Kong, Bo-Hyun;Han, Won-Suk;Cho, Hyung-Koun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.177-177
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    • 2007
  • ZnO는 3.36eV의 넓은 밴드캡을 가지는 II-IV족 반도체로써 태양전지, LED와 같은 광학적 소자로 이용이 기대가 되는 물질이다. 더욱이, 상온에서의 60meV에 해당하는 큰 엑시톤 에너지와 밴드캡 에지니어링이 가능하다는 장점 때문에 광학적 소자로 널리 이용되고 있는 GaN을 대체할 수 있는 물질로 주목을 받고 있다. 하지만, p-type ZnO는 형성이 어렵고 낮은 이동도와 케리어 농도의 특성을 보이고, 대기 중에 장시간 노출할 경우 n-type ZnO의 특성으로 돌아가는 불안정성을 보이고 있다. 최근에 몇몇의 연구자들에 의해 V족의 원소인 P(phosphorous), N(nitrogen), As(arsenic))를 도핑하여 p-type ZnO의 형성에 대한 논문이 발표되고 있다. 또한, V족 원소 중에 P는 p-type ZnO 형성에 효과적인 도핑 물질로 보고되 고 있다. 본 연구는 마그네트론 스퍼터링을 이용하여 다양한 온도에서 성장된 P도핑 ZnO 박막의 특성에 대해 연구하였다. P도핑된 ZnO 박막은 사파이어 기판에 buffer층을 사용한 Insulator 특성의 ZnO박막위에 400, 500, 600, $700^{\circ}C$에서 성장되 었다. 박막의 특성 분석에는 325nm의 파장을 가지는 He-Cd의 레이져 광원을 사용하여 10K의 저온 PL과 0.5T의 자기장을 사용한 van der Pauw configuration에 의한 Hall effect측정, 그리고 결정성 분석에는 XRD와 TEM을 이용하였다. 상온 Hall-effect 측정 결과, $400{\sim}600^{\circ}C$ 에서 성장된 박막은 n-type의 특성을 보였고, $700^{\circ}C$에서 성장된 Phosphorous 도핑 ZnO박막은 $1.19{\times}10^{17}$의 캐리어 농도를 가지는 p-type의 특성을 보였다. 그리고 XRD분석과 TEM분석을 통하여 박막의 성장온도가 증가 할수록 P도핑된 ZnO박막의 결정성이 향상되는 것을 알 수 있었다. 또한 10K의 저온 PL분석을 통해 p도핑에 의한 액셉터에 관련된 피크들을 관찰할 수 있었다.

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Study on the Coefficient of Thermal Expansion for Composites Containing 2-Dimensional Ellipsoidal Inclusions (2차원 타원형의 충전제를 함유하는 복합재료의 열팽창 계수 연구)

  • Lee, Kee-Yoon;Kim, Kyung-Hwan;Jeoung, Sun-Kyoung;Jeon, Hyoung-Jin;Joo, Sang-Il
    • Polymer(Korea)
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    • v.31 no.2
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    • pp.160-167
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    • 2007
  • This paper proposes a model for the solutions predicting the coefficient of thermal expansion of composites including fiber-like shaped$(a_1>a_2=a_3)$ and disk-like shaped$(a_1=a_2>a_3)$ inclusions like two dimensional geometries, which was analyzed by one axis and a single aspect ratio, $(\rho_\alpha=a_1/a_3)$. The analysis follows the procedure developed for elastic moduli by using the Lee and Paul's approach. The effects of the aspect ratio on the coefficient of thermal expansion of composites containing aligned isotropic inclusions are examined. This model should be limited to analyze the composites with unidirectionally aligned inclusions and with complete binding to each other of both matrix and inclusions having homogeneous properties. The longitudinal coefficients of thermal expansion $\alpha_{11}$ decrease and approach the coefficient of thermal expansion of filler, as the aspect ratios increase. However, the transverse coefficients of thermal expansion $\alpha_{33}$ increase or decrease with the aspect ratios.

LiDAR Chip for Automated Geo-referencing of High-Resolution Satellite Imagery (라이다 칩을 이용한 고해상도 위성영상의 자동좌표등록)

  • Lee, Chang No;Oh, Jae Hong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.319-326
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    • 2014
  • The accurate geo-referencing processes that apply ground control points is prerequisite for effective end use of HRSI (High-resolution satellite imagery). Since the conventional control point acquisition by human operator takes long time, demands for the automated matching to existing reference data has been increasing its popularity. Among many options of reference data, the airborne LiDAR (Light Detection And Ranging) data shows high potential due to its high spatial resolution and vertical accuracy. Additionally, it is in the form of 3-dimensional point cloud free from the relief displacement. Recently, a new matching method between LiDAR data and HRSI was proposed that is based on the image projection of whole LiDAR data into HRSI domain, however, importing and processing the large amount of LiDAR data considered as time-consuming. Therefore, we wmotivated to ere propose a local LiDAR chip generation for the HRSI geo-referencing. In the procedure, a LiDAR point cloud was rasterized into an ortho image with the digital elevation model. After then, we selected local areas, which of containing meaningful amount of edge information to create LiDAR chips of small data size. We tested the LiDAR chips for fully-automated geo-referencing with Kompsat-2 and Kompsat-3 data. Finally, the experimental results showed one-pixel level of mean accuracy.

An Exploratory Research on Social Workers' Attitude and Related Factors about Indoor Air Quality Management of Social Welfare Facilities (사회복지시설 종사자의 실내공기질 관리에 대한 태도와 관련 요인에 관한 탐색적 연구)

  • Bae, Jin-Hee
    • The Journal of the Korea Contents Association
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    • v.17 no.5
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    • pp.273-284
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    • 2017
  • As these days people spend most of time at inner space, indoor air quality affect human life seriously. Government manage indoor air quality of various facilities based on different laws. Government released that they would try to protect environment for vulnerable people such children and seniors from indoor air pollutants in 2015. But social welfare facilities are exception under current legal systems. Clients of social welfare residential facilities are the disables, the elderly, homeless and children and they usually stay inner space very long time. The purpose of this study is explore workers' attitude and related factors about indoor air quality management of social welfare facilities. 69.5% of respondents agree to government's indoor air quality management, 80.9% of respondents think social welfare facilities must be included in legal system for indoor air quality management. Environmental awareness and law awareness were related with attitude to indoor air quality management. Based on the results of the analysis, I propose the amendment of law on indoor air quality of the Ministry of Environment, cost burden of central or local government and the necessity of education and research on indoor air quality management in social welfare facilities.

A Study on Interdisciplinary Understanding of Modern Science Culture - Focusing on Case Study of 'STS Course' (현대 과학문화의 간학문적 이해에 대한 연구 - '과학기술과 사회' 교양강좌 사례분석을 중심으로)

  • Kim Dong-Kwang
    • Journal of Science and Technology Studies
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    • v.4 no.2 s.8
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    • pp.33-66
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    • 2004
  • In these days, science is too complex and comprehensive scientific practices to be reduced to scientific knowledge. Also it's actors go beyond the limit of scientist society to the broad range of supporting system scientific journalism, education, and business. Science is very important cultural practice of our times. This Study focus on the effect of interdisciplinary approach in understanding modern science culture. First, this paper suggest the approach of public understanding of science(PUS) as a framework PUS has provided new perspectives for the relation of scientific knowledge and understanding. Traditional approach(so-called 'deficit model') regarded understanding as mere transportation of scientific knowledge. So it may be called 'knowledge-oriented approach' to understanding. But PUS consider understanding process of 'dynamic reconstructing' which is occurred in complex socio-cultural context. Second, this article analysis the Korea University STS course(2002-2003) 'Science Technology & Society' as the case study. The case study examine how interdisciplinary approach help students to understand 'sciene in the making'.

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교실은 어떻게 '스마트'해지는가?

  • JEONG, Hanbyul
    • Journal of Science and Technology Studies
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    • v.19 no.3
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    • pp.201-246
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    • 2019
  • Information technology is sometimes considered as a cause that puts education in a big crisis, or it can be seen as a savior. In 2011, the Korean government announced that it would innovate education and build a talented nation by bringing IT into schools of public education system through the SMART education policy. The policy initiative aimed to establish a standard classroom models that can be diffused all over the country's schools so that teachers and students may become familiar of using devices such as tablet PCs and laptops. This paper analyzes how the smart classrooms caused friction in the actual education practices. To this end, I analyzed the direction and ideals of the SMART education policy by reading government policy document and design guidelines officially published, and visited three elementary schools that are actually building and operating a smart classroom environment to visit the facilities and have in-depth interviews with teachers and technicians. The ideal type of classroom proposed by the smart education policy was a package equipped with various functions at once in a neatly designed space like a "model house", but it was difficult to be used as a normal classroom in everyday life of school. Instead of copying and installing the model, each school decided to get "smart" in its own way, depending on how factors such as size, local characteristics, socioeconomic conditions of students and teachers, teacher experiences, and the level of existing infrastructure were combined. In Elementary School A, the machines tamed specific space of the school to create their own space, while following the rules of the school for being mobile. Although Elementary School B could not construct fully supported environment that encompassed the entire school, the system was organized with the help of well trained teacher's experiences in other schools. In Elementary School C, the machines are concentrated on specific classrooms and they promote teacher's professionalism. The components of the smart classroom were disassembled and recombined in context to make each school's classroom "smart".

Current Status of Hyperspectral Remote Sensing: Principle, Data Processing Techniques, and Applications (초분광 원격탐사의 특성, 처리기법 및 활용 현용)

  • Kim Sun-Hwa;Ma Jung-Rim;Kook Min-Jung;Lee Kyu-Sung
    • Korean Journal of Remote Sensing
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    • v.21 no.4
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    • pp.341-369
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    • 2005
  • Hyperspectral images have emerged as a new and promising remote sensing data that can overcome the limitations of existing optical image data. This study was designed to provide a comprehensive review on definition, data processing methods, and applications of hyperspectral data. Various types of airborne, spaceborne, and field hyperspectral image sensors were surveyed from the available literatures and internet search. To understand the current status of hyperspectral remote sensing technology and research development, we collected several hundreds research papers from international journals (IEEE Transactions on Geoscience and Remote Sensing, International Journal of Remote Sensing, Remote Sensing of Environment and AVIRIS Workshop Proceedings), and categorized them by sensor types, data processing techniques, and applications. Although several hyperspectral sensors have been developing, AVIRIS has been a primary data source that the most hyperspectral remote sensing researches were relied on. Since hyperspectral data have very large data volume with many spectral bands, several data processing techniques that are particularly oriented to hyperspectral data have been developed. Although atmospheric correction, spectral mixture analysis, and spectral feature extraction are among those processing techniques, they are still in experimental stage and need further refinement until the fully operational adaptation. Geology and mineral exploration were major application in early stage of hyperspectral sensing because of the distinct spectral features of rock and minerals that could be easily observed with hyperspectral data. The applications of hyperspectral sensing have been expanding to vegetation, water resources, and military areas where the multispectral sensing was not very effective to extract necessary information.