• Title/Summary/Keyword: 전반확산

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Oxidation behavior on the surface of titanium metal specimens at high temperatures (300~1000℃) (고온 (300~1000 ℃)에서 티타늄 금속시편의 표면 산화거동)

  • Park, Yang-Soon;Han, Sun-Ho;Song, Kyuseok
    • Analytical Science and Technology
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    • v.22 no.6
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    • pp.464-470
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    • 2009
  • For the investigation of the oxidation behavior for titanium metal at various temperatures, titanium specimens were heated for 2 hours in the range of $300{\sim}1000^{\circ}C$, individually. And then X-ray diffraction(XRD), scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS) and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopic analyses were carried out. At $300^{\circ}C$, infrared absorption bands on the surface of the titanium specimen were shown in a spectrum by the oxygen uptake of titanium metal(hexagonal). At increased temperature, not only infrared absorption bands but also X-ray diffraction peaks for the titanium oxide were grown and shifted to low wave number ($cm^{-1}$) and angle($^{\circ}$) due to the more oxygen diffusion into titanium metal. At $700^{\circ}C$, $Ti_3O$ (hexagonal phase) was identified by X-ray diffractometer. $TiO_2$ (rutile, tetragonal phase) layer was produced on the surface of the specimen below $1{\mu}m$ in thickness at $600^{\circ}C$, and grown about $2{\mu}m$ at $700^{\circ}C$ and with $110{\mu}m$ in thickness at $1000^{\circ}C$. Above $900^{\circ}C$, (110) plane of the crystal on the surface of rutile-$TiO_2$ layer was grown.

A Study on Ventilation Characteristics in Fuel Preparation Room of Hydrogen Fueled Vessel (수소추진선박의 연료준비실내의 환기특성에 관한 연구)

  • Bo Rim Ryu;Phan Anh Duong;Quoc Huy Nguyen;Hokeun Kang
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.11a
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    • pp.158-159
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    • 2022
  • Due to the climate crisis, various environmental regulations including greenhouse gas reduction are in effect. This is not limited to any specific industry sector, but is affecting the entire industry worldwide. For this reason, the IMO and governments of each country are announcing strategies and policies related to the shipbuilding and shipping industries. The current regulations can be partially resolved through additional facilities such as scrubbers while using existing fossil fuels, but ultimately, the emission of greenhouse gases such as CO2 from the exhaust gases generated by ships must be restricted through energy conversion. To this end, it is necessary to develop fuels that can replace traditional fuels such as oil and natural gas. Among them, hydrogen is attracting attention as a clean energy that does not emit pollutants when used as a fuel. However, hydrogen has a wide explosive range and a fast dispersion speed, so research on this is necessary. Therefore, in this paper, when hydrogen leakage occurs in the fuel preparation room of a hydrogen-powered ship, the trend was analyzed and the ventilation characteristics were investigated.

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Understanding ESG Management and the Possibility of ESG Archives (ESG 경영의 이해와 ESG 아카이브의 가능성)

  • Lim, JongChul
    • The Korean Journal of Archival Studies
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    • no.79
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    • pp.33-82
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    • 2024
  • Interest in ESG management, which spread through the UN PRI in 2006, has recently spread throughout our society. Consumers use a company's activeness in the ESG field as the standard of consumption behavior, and the international community is reorganizing and strengthening various regulatory measures. In the investment market, non-financial performance (ESG information) is used as an important investment indicator along with financial performance (credit rating). Due to these changes in the corporate evaluation paradigm and market pressure, if a company neglects ESG response activities, it is more likely to be excluded from market selection, and accordingly, the importance of ESG management is also increasing. Companies are making various efforts to secure legitimacy in response to these market pressures, but in the process, it is difficult to systematically manage and utilize records/data that are the basis for ESG management. For a basic understanding of ESG management, this paper summarizes the emerging process of ESG and the current ESG-related regulations applied to companies. Through this, it can be seen that ESG management is not carried out with the good will of the company, but is accepted as a management strategy for the survival of the company according to the change in the corporate evaluation paradigm. Through interviews with the company's ESG-related personnel, the company's ESG response process was divided into passive communication and active communication, and the problems identified during the interview were summarized for each communication type. In addition, in the process of passively and actively communicating ESG management information with internal and external stakeholders, the possibility that ESG archives can function as a tool to overcome problems for each communication type was raised, and five types of ESG archives that can play this role were presented.

A Proposal of Direction of Wind Ventilation Forest through Urban Condition Analysis - A Case Study of Pyeongtaek-si - (도시 여건 분석을 통한 바람길숲 조성방향 제시 - 평택시를 사례로 -)

  • SON, Jeong-Min;EUM, Jeong-Hee;SUNG, Uk-Je;BAEK, Jun-Beom;KIM, Ju-Eun;OH, Jeong-Hak
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.4
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    • pp.101-119
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    • 2020
  • Recently, as a plan to improve the particulate matter and thermal environment in the city, urban forests acting as wind ventilation corridor(wind ventilation forest) are promoted nationwide. This study analyzed the conditions for the creation of wind ventilation forest(vulnerable areas of the particulate matter and thermal environment, distribution of wind ventilation forest, characteristics of ventilation corridor) of in Pyeongtae-si, one of the target cities of wind ventilation forest project. Based on the results, the direction of developing on the wind ventilation forest in Pyeongtaek-si was suggested. As a result of deriving areas vulnerable to particulate matter and thermal environment, it was most vulnerable in urban areas in the eastern area of Pyeongtaek-si. Especially, emissions were high from industrial complexes and roads such as the Pyeongtaek-si thermal power plant, ports, and the national road no. 1. The wind ventilation forest in Pyeongtaek-si was distributed with small-scale windgenerating forests, wind-spreading forests, and wind-connection forests fragmented and disconnected. The characteristic of the overall wind ventilation corridor in Pyeongtaek-si is that the cold air generated from Mt.Mubong, etc., strongly flowed into Pyeongtaek-si and flowed in the northwest direction. Therefore, it is necessary to preserve and expand the wind-generating forests in Pyeongtaek-si in the long term, and it was important to create wind-spreading forests and wind-connection forests so that cold air could flow into the vulnerable area. In addition, in industrial complexes and roads where particulate matter is generated, planting techniques should be applied to prevent the spread of particulate matte to surrounding areas by creating wind-spreading forests considering the particulate matter blocking. This study can be used not only as the basis data for wind ventilation forest project in Pyeongtaek-si, but also as the basis data for urban forest creation and management.

A Study on the Importance and Improvement Direction of Science Communication by Analyzing Articles of the Super Blue Moon (슈퍼블루문 기사 내용분석을 통한 과학 커뮤니케이션의 중요성 및 개선방향 연구)

  • Ah-Chim Sul;Hyoungbum Kim;Yonggi Kim
    • Journal of the Korean Society of Earth Science Education
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    • v.17 no.2
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    • pp.86-101
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    • 2024
  • The purpose of this study is to provide basic data on the importance of accurate scientific communication and the current status of popular astronomy based on science articles that occurred during the so-called Super Blue Moon astronomical phenomenon in August 2023. To this end, the subjects were divided into non-experts, quasi-experts, and experts based on the degree of knowledge of the astronomical universe to investigate the data interpretation ability of astronomical science information and to analyze the causes of errors in the interpretation process through in-depth interviews. We also investigated the favorability and reliability of research institutes that strive to provide scientific information and the media that strive to spread it and also investigated the changes in existing favorability and reliability when incorrect scientific information spreads, as in this case. Although there were differences in the interpretation of scientific information about the astronomical universe depending on the cognitive aspect, the influence of linguistic elements or literacy, which could be called communication, could not be ignored. In particular, it was confirmed that misconceptions inherent in the existing research subjects could be expressed, leading to errors in accurate information interpretation. In addition, after recognizing that errors were included in the spread of scientific information, the subjects' favorability toward research institutes and the media fell 12.30% and 17.58%, respectively, while reliability fell 19.40% for research institutes and 24.49% for media outlets. Regardless of the cause of the error, the importance of providing accurate scientific information is further emphasized, considering that the overall favorability and reliability of both research institutes and the media decline. In order for research institutes and media outlets to spread accurate scientific information about the astronomical universe based on the public's trust, it is necessary to establish a system that can accurately deliver error-free information generated by research institutes related to astronomical space to media or science communicators and to develop a system that quickly retrieves and corrects incorrect scientific information through continuous monitoring.

Video Copyright Protection through Watermarking of Wavelet Transform based on the Frequency (주파수기반 웨이브릿 변환의 워터마킹을 통한 동영상 저작권 보호에 관한 연구)

  • Han, Mi-Ja;Kim, Dan-Hwan;Jung, Chang-Ryul;Jeong, Byeong-Yeol;Lee, Sung-Keun;Koh, Jin-Kwang
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.535-539
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    • 2008
  • With the advancement which development and information communication of the computer is quick about lower with multimedia technical diffusion of network base the necessity the use of the digital image technique which is various regarding the protection of sharp increasing multimedia contents raised its head in the social whole. The copyright protection against a multimedia data hazard the authentication techniques it will be able to confirm the content authentication, ownership authentication, illegal copy of the image which stands is demanded. confronts to the water marking technique of existing and the researches the fact that against a picture is most. In this paper, It does not damage the video data. As inserts copyright information and it protects the copyright. It is with a copyright protection which leads the wavelet transform which is a watermark of frequency base from visual system viewpoint in the human being center with it proposes the watermarking technique against a forgery prevention.

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A Study on the Paperless Waiting Order Count System for Green IT (Green IT를 위한 Paperless 순번대기표 시스템에 관한 연구)

  • Kang, Min-Sik
    • Journal of Digital Contents Society
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    • v.12 no.4
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    • pp.511-518
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    • 2011
  • One of the most important paradigms in society has recently been a set of efforts to prepare for the future and to protect the environment by saving carbon that occurs in everyday life as well as in the industry. In order to successfully deal with this new paradigm, Korean government has adopted and implemented various policies including the green certification, the development of green technologies and green growth. Many agencies and organizations in both public and private sectors have established plans about the carbon savings and performed a lot of research using IT technology. For example, attempts have been made in Korea to use as electronic documents instead of paper documents using these green IT and mobile devices. This paper proposes a 'Paperless' waiting order count system using QR code and mobile phone as an example of green IT for 'Low carbon and Green growth'.

A Study on the Progression of Fire Control Policies in Joseon Dynasty - Regal & Administrative System, Planning Tools, Works and Facilities - (조선시대 금화시책(禁火施策)의 전개과정에 관한 연구 - 금화정책, 금화계획, 금화사업, 금화시설을 중심으로 -)

  • Kim, Sang-Hee;Lee, Kyung-Chan
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.3
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    • pp.12-24
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    • 2013
  • The cities of Joseon dynasty had weak structure against fire. Fires have resulted in damage on property and life. But they gave a chance to development various policies, planning tools, techniques and facilities for minimizing the damages of fire. This study aims to understand the progression of fire control policy in Joseon dynasty. Fire control policies can be divided into four categories ; fire prevention, prohibition of fire spreading, fire extinguishing and rescue system. The progression of fire control policies can be divided into three steps. In the first step, from Taejong to Moonjong, various policy, such as regal & administrative system, planning tools, fire control works & appliances have been built and executed. In the second step, from Danjong to Hyunjong, fire control work have taken the central place of fire control policy. In the third step, from Sookjong to Sunjong, development of fire control appliances have taken the central place of fire control policy.

시뮬레이션을 통한 실리콘 나노선의 전기적 특성 연구

  • Go, Jae-U;Park, Seong-Ju;Lee, Seon-Hong;Baek, In-Bok;Lee, Seong-Jae;Jang, Mun-Gyu
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.408-408
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    • 2012
  • 반세기가 지나는 동안 우리는 반도체의 크기가 계속해서 작아지는 것을 경험해왔다. 반도체 디바이스들의 차원이 100 nm 이하로 작아지면서, 나노와이어나 나노튜브로 이루어진 나노 소자들은 필연적으로 양자효과[1] 같은 저차원효과가 나타나게 된다. 특히 1차원 반도체 구조에서는 전자상태 밀도의 변화에 수반되는 전자-포논의 상호작용이 감소되어 전자이동도가 증가할 것으로 예측되었고, 이러한 이동도의 증가는 그동안 나노와이어나 나노튜브의 전기 전도도 증가가 일어난 실험적 데이터를 설명하는 이론적 받침이 되었다[2]. 한편 일차원 반도체 구조 체에서는 채널의 저차원화에 따른 전기장의 불균일성이 심화되고 이로 인하여 벌크와 매우 다른 전기수송 특성이 나타날 수 있는데 이러한 점이 그동안 간과되어 왔다. 본 연구에서는 시뮬레이션을 통하여 양자효과를 배제한 정전기적인 저차원 효과만으로도 전기 전도도가 증가할 수 있음을 보이고자 한다. 우리는 푸아송 방정식과 표동-확산 방정식을 SILVACO사의 ATLAS 3D 시뮬레이터를 이용하여 풀었다. 이 시뮬레이션에 사용된 실리콘 나노와이어는 길이를 $2{\mu}m$로 고정시키고 다양한 정사각형 단면적을 가진 구조로 하였다. 여기서 정사각형의 한변을 10nm 에서 100 nm까지 변화시켰다. 실리콘 채널의 도핑농도가 $1{{\times}}1016cm-3$일 경우, 낮은 전압, 즉 < 0.5 V 이하 영역에서는 벌크와 같은 선형적인 전류-전압 특성이 나타나지만, 그 이상의 전압 영역에서는 전류-전압 그래프가 위로 휘어지며(super-linear) 전기전도도가 확연히 증가함을 알 수 있었다. 예를 들어 2 V에서는 벌크에 비하여 흐르는 전류가 2배나 더 향상되었다. 이런 비선형적인 성질은 높은 전압을 인가하였을 때 나노와이어 채널 전반에 걸쳐 charge neutrality가 깨지게 되고 전하밀도가 증가하여 전도도 증가가 일어나는 것으로 밝혀졌다. 이 결과는 기존의 나노선에서의 전기전도도 증가 현상을 설명할 수 있는 대안을 제공할 수 있다.

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An Anonymity-Preserving User Authentication and Authorization Model for Ubiquitous Computing Environments (유비쿼터스 컴퓨팅 환경을 위한 익명성을 보장하는 사용자 인증 및 접근제어 모델)

  • Kang Myung-Hee;Ryou Hwang-Bin
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.42 no.4 s.304
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    • pp.25-32
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    • 2005
  • The spread of mobile devices, PDAs and sensors has enabled the construction of ubiquitous computing environments, transforming regular physical spaces into 'Smart space' augmented with intelligence and enhanced with services. However, the deployment of this computing paradigm in real-life is disturbed by poor security, particularly, the lack of proper authentication and authorization techniques. Also, it is very important not only to find security measures but also to preserve user privacy in ubiquitous computing environments. In this Paper, we propose efficient user authentication and authorization model with anonymity for the privacy-preserving for ubiquitous computing environments. Our model is suitable for distributed environments with the computational constrained devices by using MAC-based anonymous certificate and security association token instead of using Public key encryption technique. And our Proposed Protocol is better than Kerberos system in sense of cryptographic computation processing.