• 제목/요약/키워드: 사고종류

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Microencapsulation of SrAl2O4 : Eu2+,Dy3+ Phosphorescent Phosphor for Enhanced Visibility of Road Lanes (차선의 시인성 향상을 위한 SrAl2O4 : Eu2+,Dy3+ 축광 마이크로 캡슐화에 관한 연구)

  • Park, Jae Il;Jeong, Soo Hwan;Cheong, In Woo
    • Journal of Adhesion and Interface
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    • 제17권3호
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    • pp.110-116
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    • 2016
  • A decrease in the retro-reflectivity of glass-bead-covered road paint because of a rainwater film significantly reduces the visibility of drivers at night, and has been considered as a critical cause of traffic accidents. For enhanced visibility, the microencapsulation of hydrophobically modified $SrAl_2O_4:Eu^{2+}$,$Dy^{3+}$ phosphorescent phosphor was carried out via suspension polymerization of methyl methacrylate (MMA). The effects of surface modification agent and radical initiator types, loading amount of phosphorescent phosphor, and microcapsule size on the phosphor content ($W_{TGA}$) in the luminous poly(methyl methacrylate) (PMMA) microcapsules were investigated by thermogravimetric analyses (TGA). It was found that the $W_{TGA}$ value was ranged from 7 wt% to 81 wt%, which suggests suspension polymerization is suitable for the preparation of luminous microcapsules with a wide range of phosphor content. At a lower loading amount of phosphor, the $W_{TGA}$ value obviously increased as the microcapsule size decreased; however, the $W_{TGA}$ values with a higher loading amount of phosphor were less affected by the microcapsule size. The luminous microcapsules with the size range of $425{\sim}710{\mu}m$ were collected and tested as a luminous road lanes. It was found that luminance intensities of the microcapsule-coated plates remained higher than $300mcd/m^2$ for up to 100 s in darkness after 20 min of light emitting diode lamp irradiation. The results suggest that the luminous microcapsules can be a candidate for the replacement of glass beads for enhanced visibility of drivers.

A Study on the Students' Life and Educational Experiences at Chungbuk National University (충북대학교 학생들의 학생생활·교육경험 실태분석)

  • Nah, MinJoo;Choi, Wonseok;Cha, Jicheol;Lee, Gilgae
    • Korean Educational Research Journal
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    • 제37권1호
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    • pp.67-101
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    • 2016
  • The purpose of this study is to explore and propose policy alternatives by examining students' educational experiences at Chungbuk National University (CBNU). Some of the outstanding research findings of the study as follows. Students at CBNU think that they are capable of team-working and utilizing internet while less so with foreign language skill. With regard to academic achievement, students responded that they have seen a relatively low outcome in foreign language competency. In terms of their job placement, CBNU students highly recognize their logical thinking skill, creativity, and activity, whereas lower satisfaction with social service, study abroad, and internship experience. For further development of the survey analysis, this study suggests additional items included to make a sophisticated analysis possible such as scholarship, part-time job, educational outcome. This is expected to allow researchers to tab into the effect of finance of CBNU students. More detailed information on students' characteristics also need to be added; collaborative learning, student faculty interaction, co-work with students from diverse background, etc., which would allow the analysis of the impact of extra-curricula activities.

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예비구조설계에서의 상호작용방식에 따른 컴퓨터 활용방안

  • 정종현
    • Computational Structural Engineering
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    • 제12권1호
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    • pp.86-94
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    • 1999
  • 예비구조설계에서는 구조시스템 대안의 생성과 발전, 여러 방법과 대상에 따른 해석과 설계 다양한 요구조건과 구조적 특성을 고려한 여러 구조시스템 대안의 비교 및 선택 과정을 거친다. 그리고, 이러한 각 과정은 구조설계자의 경험적 지식을 바탕으로 하는 종합적인 사고와 판단에 따라서 단계적, 반복적으로 이루어진다. 그러므로, 예비구조설계에서는 정형화된 자료와 작어뿐 아니라 비정형화된 자료와 작업도 처리해야 한다. 따라서, 컴퓨터는 정형화된 자료와 작업을, 구조설계자는 비정형화된 자료와 작업을 직접 처리하고 이를 상호작용을 통하여 교환 및 지시하는 방식, 즉 구조설계자와 컴퓨터의 역할분담에 기초한 상호작용방식을 통하여 예비구조설계에 컴퓨터를 효율적으로 활용할 수 있을 것이다. 구조설계자와 컴퓨터의 역할분담에 기초한 상호작용을 원활히 지원하기 위해서는 구조시스템 대안의 기하학적 향상, 재료에 대한 자료를 효과적으로 제시할 수 있는 3차원 관점, 각 구조시스템 대안을 검토하고 비교하는 사항이 되는 다양한 요구조건에 대한 자료들을 관리하고 제시할수 있는 요구조건 관점이 필요하다. 그리고 예비 구조설계가 진행되어 온 과정, 방향, 설계의도등의 파악을 위한 바탕이 될 수 있는 작업과정관점, 구조시스템 대안 발전 관점이 필요하다. 예비구조설계의 프로세스 조절을 위한 상호작용을 효과적으로 지원하기 위해서는 컴퓨터가 수행 할 수 있는 정형화된 작업들을 예비구조설계의 진행순서인 구조시스템 대안의 생성과 발전, 구조시스템 대안의 해석과 설계, 구조시스템 대안의 선택에 따라서 나열하여 제시할 필요가 있다. 이를 통해서 구조설계자는 자신의 판단에 따라서 다음에 수행해야 할 작업을 결정하고, 그에 해당하는 정형화된 작업을 컴퓨터가 제시한 작업 중에서 선택하고 그 수행을 지시하여 자신의 경험적 지식과 설계의도에 맞추어 예비구조설계의 프로세스를 조절할 수 있다.정조합력은 유의차가 컸으나, 상반조합 능력은 없었다. 교배친의 우성효과는 컸다. 잡종강세 환경변이 및 상가적 작용도 컸다. 우성의 방향은 정의 방향이었으므로 우성귀전자가 크게 작용하였다. 이들 형질들의 귀전자들은 초우성을 나타내었다. 교배친의 자견층중의 우성순서는 잠120>잠114>잠108>잠119>잠118>잠107>잠117>잠113 순이었고, 웅견층중에서는 잠114>잠108>잠120>잠117>잠118>잠107>잠119>잠119>잠113 순이었다. 자견층 비율에서는 광의의 귀전력이 협의의 귀전력보다 컸고, 웅견층 비율에서는 같았다, 견층 비율에서는 일반조합 능력은 크게 나타났으나, 특정조합 능력과 상반조직 능력은 나타나지 않았다. 자견층 비율에서 교배친의 우성효과는 컸다. 자견층 비율에서는 교배친의 우성효과는 적었다. 자웅견층 비율의 잡종 강세는 적게 나타났다. 환경변이와 상가적 작계는 자웅견층 비율에서는 크게 나타났다. 우성의 방향은 자견층 비율에서는 정의 방향으로 우성 귀전자가 크게 작용하였으며, 자견층 비율에서는 정의 방향으로 우성 귀전자가 부분적으로 작용하였다. 교배친의 자견층 비율의 우성순서는 잠117>잠114>잠108>잠120>잠118>잠119>잠107>잠113 순이었고, 자견층 비율에서는 잠114>잠117>잠108>잠118>잠107>잠119>잠113>잠120의 순이었다.지방산의 조성이 많은 차이를 보였다.{2+}$ 26 및 $Na^+$ 26 mg $L^{-1}$이었다. 양액 재배 후 버려지는 폐양액 중의 무기성분 함량은 양액재배에 이용되는 원수에 비해 상당히 높아졌다.료로서 응용 가능성이 있음을 시사한다.약재료인 약초류 등을 이용하였는데 오랫동안 푹 삶아 그물에 곡류 등을 넣어 죽이나 밥으로 조리하였으며 면으로도 조리하였다. 이상과 같이 조선시대 주식류의 종류 및 조리방법에 대한

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An Analysis of the Factors that Change the Science Academic Emotion of Elementary Students in Storytelling Classes Using Fairy Tales Connected to Exhibits in Science Museum (과학관 전시물 연계 동화 활용 스토리텔링 수업이 초등학생의 과학학습정서에 변화를 가져온 요인 분석)

  • Choi, So-Young;Shin, Youngjoon
    • Journal of Science Education
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    • 제43권3호
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    • pp.300-317
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    • 2019
  • This study aims to find how storytelling classes using fairy tales related to science museum exhibits have an effect on positive experience about science. For this study, the theoretical background and preceding studies on the relevance of science education and literature were collected and based on the characteristics of assimilation and the educational value of assimilation, naturally connected to the exhibits in relation to their own life, so that individuals could explore science even out-of-school. Four types of activities were developed by linking four fairy tales mentioned in elementary school textbooks to the G science museum exhibits. Seven elementary school teachers verified the validity of the activity materials. Classes through the developed activity materials were conducted four times in a row, one and a half hours at every turn for 10 students. A positive experience about science test was conducted on the students in a study to confirm that this activity has caused significant changes in science academic emotion among sub-domains of positive experience about science. In order to find the factors that affected the science academic emotion, we interviewed the students in the study and their parents. The results of this study show that the use of fairy tales related to science museum exhibits has led to a significant change in science academic emotion by reducing the burden of learning through the exhibition experience at the science museum, which creates scientific curiosity and recognizes them as a playground.

Determination of Design Basis for a Storage System for Spent Fuel in Korea (국내 사용후핵연료 저장시스템의 설계기준 설정 인자 고찰)

  • Yoon, Jeong-Hyoun;Lee, Eun-Yong;Woo, Sang-In;Kim, Tae-Man
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • 제9권2호
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    • pp.113-119
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    • 2011
  • Safe operation and maintenance of engineered dry storage systems for spent fuel from nuclear power plants basically depends on adequately adopted design requirements. The most important design target of the system are those which provide the necessary assurances that spent fuel can be received, handled, stored and retrieved without undue risk to health and safety of workers and the public. To achieve these objectives, the design of the system incorporates features to remove spent fuel residual heat, to provide for radiation protection, and to maintain containment over the lifespan of the system as specified in the design specifications. The features also provide for all possible anticipated operational occurrences and design basis events in accordance with the design basis as guided by the designated regulations. The general performance requirements of a projected storage system are introduced in this paper. The storage system is designed to store fuel assemblies in associated with designated regulatory requirements. Small increases/decreases in maximum burnup can be adjusted with cooling time. These variations are compensated for by a corresponding small site-specific increase/decrease in the design basis-cooling period, as long as the maximum heat load and radioactivity of loaded fuel assemblies are met. Generic design basis events considered for the storage system are summarized. Shielding and radiological requirements along with mechanical and structural are derived in this study.

Classification of BcN Vulnerabilities Based on Extended X.805 (X.805를 확장한 BcN 취약성 분류 체계)

  • Yoon Jong-Lim;Song Young-Ho;Min Byoung-Joon;Lee Tai-Jin
    • The KIPS Transactions:PartC
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    • 제13C권4호
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    • pp.427-434
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    • 2006
  • Broadband Convergence Network(BcN) is a critical infrastructure to provide wired-and-wireless high-quality multimedia services by converging communication and broadcasting systems, However, there exist possible danger to spread the damage of an intrusion incident within an individual network to the whole network due to the convergence and newly generated threats according to the advent of various services roaming vertically and horizontally. In order to cope with these new threats, we need to analyze the vulnerabilities of BcN in a system architecture aspect and classify them in a systematic way and to make the results to be utilized in preparing proper countermeasures, In this paper, we propose a new classification of vulnerabilities which has been extended from the ITU-T recommendation X.805, which defines the security related architectural elements. This new classification includes system elements to be protected for each service, possible attack strategies, resulting damage and its criticalness, and effective countermeasures. The new classification method is compared with the existing methods of CVE(Common Vulnerabilities and Exposures) and CERT/CC(Computer Emergency Response Team/Coordination Center), and the result of an application to one of typical services, VoIP(Voice over IP) and the development of vulnerability database and its management software tool are presented in the paper. The consequence of the research presented in the paper is expected to contribute to the integration of security knowledge and to the identification of newly required security techniques.

Sonar System Application for detection of underwater work space boundary using seabed type underwater equipments (착저형 수중장비를 이용한 수중작업 시 작업경계면 인식을 위한 소나시스템 활용법)

  • Shin, Changjoo;Jang, In-Sung;Won, Deokhee;Seo, Jung-min;Baek, Won-Dae;Kim, Kihun;KIM, JONG HOON
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제17권10호
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    • pp.678-684
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    • 2016
  • The detection of an underwater work space boundary is very important when an underwater construction is carried out using seabed type underwater equipment, such as underwater machines for rubble mound leveling, because it can induce industrial disasters. Therefore, divers are needed to mark the underwater work space boundary. A nylon rope is used to improve the convenience during an underwater diver's work. The results showed that the work space boundary can be detected using a sonar system. Using these results, an efficient method to detect the underwater work space boundary can be obtained when an underwater construction is carried out using seabed type underwater equipment.

The Re-inspection on The Explanatory Model ofXi Ming of Chu Hsi'sThought of "Li Yi Fen Shu" (朱熹 「理一分殊」 的 <西銘> 詮釋模式再考察)

  • Lin, Le-chang
    • Journal of Korean Philosophical Society
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    • 제141권
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    • pp.167-185
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    • 2017
  • Chu Hsi inherited the proposition of Cheng Yi, and it spent him over ten years to finish writing the works of Xi Ming Jie, thus, making the thought of "Li Yi Fen Shu" bethe explanatory model of Xi Ming, therefore, playing the role to determine the tone of Xi Ming. At first, the thought of "Li Yi Fen Shu is a concept to embody the ethical significance of Xi Ming. But in terms of all the discussion about "Li Yi Fen Shu" of Chu Hsi in his life, this proposition is not only for the ethical significance of Xi Ming, but also includes much more general philosophical significance, revealing the general and special relationship of things. The former is the narrow "Li Yi Fen Shu", but the latter is the generalized one. This article won't discuss the generalized one, and it will take the narrow one as the research object. In the past research in academic circles, some scholars thinks that the proposition of "Li Yi Fen Shu" accords with the aim of Xi Ming, some others don't think so. Contrary to both of the two views, this article thinks that there is some conformity and inconformity between the explanatory model of "Li Yi Fen Shu" of Chu Hsi and the aim of Xi Ming. In other words, Contributions and limitations coexist when Chu Hsi explains Xi Ming in the model of "Li Yi Fen Shu", and there is not only the development to the intention of Xi Ming, but alsothe far meaning away from the aim of Xi Ming.

The Forecast on the Benefit of Traffic Safety Facility for the Inland Waterway in Cambodia -Focusing on the section between Phnom Penh and Chong Kneas port- (캄보디아 내륙수로의 교통안전시설에 대한 편익추정 -프롬펜과 총크니아스항 구간을 대상으로-)

  • Kim, Jung-Hoon
    • Journal of Korea Port Economic Association
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    • 제25권2호
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    • pp.73-94
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    • 2009
  • In this paper the benefit was forecasted for traffic safety facilities to be constructed along the inland waterway between Phnom Penh and Chong Kneas(Siem Reap) port in Cambodia. First of all, the number of cruise ships passengers and cargo volumes were predicted. Second, the traffic volume of the cruise ships and cargo ships were calculated according to the prediction. Last, the safety benefit of traffic safety facilities was forecasted with the traffic after surveying the waterway accidents. The other benefit was also presented by converting the effect of relieving the emotional burden of navigators into currency value. Accordingly the entire benefit was estimated to be $14,990, $20,950 and $28,540 for pessimistic, moderate and optimistic prospects, in 2011. And then the entire benefits are calculated as $28,320, $63,060 and $95,230 for each prospect in the final estimation year 2020.

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Detection Algorithm of Road Damage and Obstacle Based on Joint Deep Learning for Driving Safety (주행 안전을 위한 joint deep learning 기반의 도로 노면 파손 및 장애물 탐지 알고리즘)

  • Shim, Seungbo;Jeong, Jae-Jin
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • 제20권2호
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    • pp.95-111
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    • 2021
  • As the population decreases in an aging society, the average age of drivers increases. Accordingly, the elderly at high risk of being in an accident need autonomous-driving vehicles. In order to secure driving safety on the road, several technologies to respond to various obstacles are required in those vehicles. Among them, technology is required to recognize static obstacles, such as poor road conditions, as well as dynamic obstacles, such as vehicles, bicycles, and people, that may be encountered while driving. In this study, we propose a deep neural network algorithm capable of simultaneously detecting these two types of obstacle. For this algorithm, we used 1,418 road images and produced annotation data that marks seven categories of dynamic obstacles and labels images to indicate road damage. As a result of training, dynamic obstacles were detected with an average accuracy of 46.22%, and road surface damage was detected with a mean intersection over union of 74.71%. In addition, the average elapsed time required to process a single image is 89ms, and this algorithm is suitable for personal mobility vehicles that are slower than ordinary vehicles. In the future, it is expected that driving safety with personal mobility vehicles will be improved by utilizing technology that detects road obstacles.