• Nuclear Engineering and Technology
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• 제52권3호
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• pp.597-609
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• 2020

Accident Tolerant Fuels have been widely studied since the Fukushima-Daiichi accident in 2011 as one of the options on how to further enhance the safety of nuclear power plants. Deposition of protective coatings on nuclear fuel claddings has been considered as a near-term concept that will reduce the high-temperature oxidation rate and enhance accidental tolerance of the cladding while providing additional benefits during normal operation and transients. This study focuses on experimental testing of Zr-based alloys coated with Cr-based coatings using Physical Vapour Deposition. The results of long-term corrosion tests, as well as tests simulating postulated accidents, are presented. Zr-1%Nb alloy used as nuclear fuel cladding serves as a substrate and Cr, CrN, Cr_xN_y layers are deposited by unbalanced magnetron sputtering and reactive magnetron sputtering. The deposition procedures are optimized in order to improve coating properties. Coated as well as reference uncoated samples were experimentally tested. The presented results include standard long-term corrosion tests at 360℃ in WWER water chemistry, burst (creep) tests and mainly single and double-sided high-temperature steam oxidation tests between 1000 and 1400℃ related to postulated Loss-of-coolant accident and Design extension conditions. Coated and reference samples were characterized pre- and post-testing using mechanical testing (microhardness, ring compression test), Thermal Evolved Gas Analysis analysis (hydrogen, oxygen concentration), optical microscopy, scanning electron microscopy (EDS, WDS, EBSD) and X-ray diffraction.

• Journal of Preventive Medicine and Public Health
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• 제38권3호
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• pp.298-306
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• 2005

Objectives : To develop measurement scales of Internet addiction, and propose a Korean Internet Addiction Index (K-IAI) and classification criteria for Internet addiction from the threshold scores developed. Methods : The identification of the concept of 'Internet addiction' was based on the literature review. To select the scales, an exploratory factor analysis was applied. A construct validation was tested by a confirmatory factor analysis (CFA) with a structured equation model (SEM). In testing the validity of the classification criteria, ANOVA and non-recursive models with SEM were applied. Results : Out of 1,080 questionnaires distributed, 1,037 were returned,; a response rate of 96%. The Cronbach-$\alpha$ of all items was over 0.75. Using an exploratory factor analysis in the condition of a 6 factor constrain as the study model proposed, 23 of the initial 28 items were identified. In testing the discriminant and convergent validity of the selected 23 scales using CFA with SEM, the Internet addiction model explained about 93% of all variances of the data collected, and all the latent variables significantly explained the designated scales. A K-IAI was proposed using the T-scores of the sum of all factor averages. In the classification of users, the basic concept was a twostandard deviation approach of the K-IAI as the criteria of MMPI. The addiction group had a score ${\geq}70$ in the K-IAI, the pre-addiction group between ${\geq}50$ and <70, and the average user group <50. The Internet use times of the classified groups were statistically different in the ANOVA and multiple comparisons. Conclusions : The K-IAI is a reliable and valid instrument for measuring Internet addiction. Moreover, the taxonomy of the groups was also verified using various methods.

• 비파괴검사학회지
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• 제24권5호
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• pp.465-475
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• 2004

본 논문은 두 편으로 구성된 스마트 능동 레이어(smart active layer, SAL) 센서 개발에 관한 첫 번째 논문으로, 구조 내에 발생하는 균열 및 손상에 의한 탄성파 검출을 위한 SAL 센서의 이론 및 개념을 연구하였다. 본 SAL 센서의 개발을 위해, 첫째, 탄성파의 기본 이론을 고찰하였고, 둘째, 이론적 토대 위에 단일 압전 disc의 유한요소해석법(finite element analysis, FEA)을 이용하여 탄성파 검출 센서로서의 가능성을 검증하였고, 셋째, 몇 종류의 압전 disc 센서와 상용 음향방출(acoustic emission, AE) 센서를 연필심 파괴시험을 통해 상호 성능을 비교하여 실험적으로 그 가능성을 확인하였다. 또한 수 개의 센서를 일정한 거리로 분포시켜서 구조물 결함의 효과적 검출 및 위치 표정이 가능한 스마트능동레이어 센서의 개념연구를 수행하였다.

• 대한정형도수물리치료학회지
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• 제17권1호
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• pp.35-44
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• 2011

Background: This study was to suggest the process of making strategy for effective intervention and evaluation on functional problems of the frozen shoulder patient applied International Classification of Functioning Disability and Health (ICF) Tools. Methods: The patient was 48years old woman with right shoulder adhesive capsulitis and calcific tendinitis. In first phase, therapists could list the information relating to functional problems used by the ICF Core set and then could confirm the interaction among the problems using the ICF assessment sheet. In second phase, therapist is needed to make the hypothesis and hypothesis testing and then set a primary functional goals and therapeutic goals in detail after prioritizing the problems to be managed based on the problem list. Lastly, after setting the confirmed problems as the purpose of intervention through the hypothesis testing, therapist could do some intervention after making a plan to solve these problems. Results: This report illustrates how to apply the process based on ICF concept into physical therapy practice. The decided hypothesis and goal that are to solve the problems the client faced were remarkably meaningful. Conclusions: Clinical decision making for the most effective intervention requires that therapists use the clinical reasoning process based on ICF concept.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제2권11호
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• pp.765-778
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• 2013

본 논문은 Rapidly-exploring Random Tree(RRT) 확장 기법을 이용하여 Stateflow 모델 기반의 블랙박스 테스트 케이스 자동 생성 방법을 제안한다. 복잡한 시스템의 경로 계획 문제를 효율적으로 해결하는 방법으로 널리 사용되고 있는RRT기법은 테스트 케이스 생성에서도 좋은 성능을 보이고 있으나, 테스트 케이스 생성에 있어서 중요한 부분을 차지하는 테스트 커버리지를 고려하고 있지 않다. 제안하는 확장 기법은 테스트 커버리지를 향상시키기 위하여 테스트 목표 달성 율의 개념을 RRT 확장에 도입하여 테스트 목표를 더 달성할 수 있는 방향으로 RRT 확장을 유도 한다. 이를 위해서 테스트 목표 달성 율을 고려한 RRT 거리 함수와 RRT 무작위 노드 생성 방법, 그리고 변형된 RRT 확장 알고리즘을 제안한다. 제안된 기법의 유용성은 실제 자동차에서 사용되는 제어 ECU들의 Stateflow 모델을 이용한 실험을 통해 기존 RRT를 이용한 테스트 케이스 생성 기법과의 성능을 비교를 통해 보인다.

• 대한기계학회논문집A
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• 제24권7호
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• pp.1779-1786
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• 2000

Most of traditional design processes of mechanical parts are regarded as sequential and discrete, since different kinds of softwas should be introduced. In this paper, we develop an integrated fram ework for virtual design and performance testing of an automobile seat. The system is composed of four modules, i.e. CAD, static analysis, dynamic analysis, and draft drawing module. In the CAD module, PRO/ENGINEER 3D seat model is created using parameters to be modified with the result of static and dynamic analysis. In the static analysis, headrest tere used in each design stage make it difficult to feedback their results to upstream process. These discrete processes may result in time loss and cost rise. In recent years, life cycle of product is reduced. To have competence with others, new concept design processt is simulated using ANSYS. In the dynamic analysis module, FMVSS201 test is simulated using DADS. Overall data flow is controlled by Motif. The advantage of the system is that even a novice can perform and review the whole design process, without a good hand at professional design/analysis S/W in each stage. The system also provides a virtual design space, where engineers in different development stage can access common data of design models. The concept could be applied to other fields and it could reduce time and money required in design process.

• 한국문헌정보학회지
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• 제21권
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• pp.103-140
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• 1991

Knowledge about career patterns of women In any profession and about factors which influence these career patterns becomes increasingly necessary because of the influx of ever-increasing numbers of women into the labor force, and the need for the development and utilization of the creative productivity of women. This study alms to investigate Korean female librarians' overall career patterns and verify relevant factors which might affect to their career patterns. As an instrument, self-reported questionnaires were sent to 1,251 full-time Korean female librarians throughout the country with regular librarian's certificate, currently engaging in public, college or university, and special libraries. Based on the data gathered, the interrelationship between their career pattern inclination and its influential factors were examined through hypothesis testing. Major findings of the survey are outlined in the following: 1). Female librarians' career patterns were classified into five categories with the group represented as Categories-2 (single; wishes to continue working after marriage; places an emphasis on the sense of occupational accomplishment and social prestige) accounted for the highest proportion$(33.4\%)$. 2). The result of the hypothesis testing revealed that there is no significant relationship statistically between social factors(parents' socio-economic status, etc.) and female librarians' career patterns. So the hypothesis concerning social factors were rejected. 3). In psychological factors(job satisfaction ; self-concept sex role attitude ; role conflict ; and achievement motivation), all except for self-concept were shown to be relevant with female librarians' stable career pattern. So the hypotheses concerning psychological factors were supported. 4). According to the result of multiple discriminant analysis conducted between the above four statistically significant psychological factors and career patterns, the most influential factor for female librarians' career patterns was job satisfaction and sex role. In conclusion, the following recommendations were made: For overall enhancement of Korean female librarianship, earlier career guidance and concrete sex role education for young women is urgent which enable them to establish correct viewpoint for their occupational career female librarians themselves' constant endeavor In maintaining positive attitude toward their job is required.

• 한국산학기술학회논문지
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• 제21권1호
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• pp.300-307
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• 2020

본 연구에서는 아직 수행되고 있지 않지만 향후 필요한 BRP(Bulletproof Reliability Program) 개념과 절차를 소개하고자 하였다. BRP 업무수행 체계는 다음과 같다. 먼저 국방부의 조정/통제 하에 기품원에서 연간 BRP 계획을 수립하고 시행을 주관한다. 다음으로 각 군 및 유관기관/부서의 의견을 수렴하여 BRP 대상 시료(Lot)를 선정하고 시험을 진행한다. 시험이 종료되면 종합된 결과를 각 군에 통보하며, 각 군에서는 후속조치를 수행한다. BRP 업무수행 절차는 매년 평가계획을 수립하는 사업(평가) 계획단계, 수립된 계획에 따라 일반검사, 기능시험, 운용시험 등을 수행하는 시험단계, 결과를 종합·분석하고 방탄물자의 성능 등을 감안하여 적정한 등급으로 판정하는 평가/분석단계, 그 결과에 따른 각 군의 후속조치 단계로 이루어져 있다. BRP 수행을 위한 제언은 다음과 같다. 첫째, 현재 일부 적체되는 시험물량과 개발 중인 워리어 플랫폼, 향후 발생할 BRP 물량을 적시에 시험하여 방탄물자의 적시 조달 및 장병의 안전성 향상, 국방예산의 절감을 위한 추가적인 시험장 건설이 필요하다. 둘째, 현재 사격시험만을 통한 방탄시험을 넘어 방탄물자의 신뢰성 평가방법을 개발하고 적용하는 것이 필요하다. 셋째, BRP가 장병의 안전성 보장 및 전투력 향상을 위한 필수적인 것임을 알리고 관련 업무의 시급성과 지원 필요성을 주요 관리자와 지휘관들에게 인식시키는 것이 필요하다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.47-47
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• 2010

Over the past 20 years, constant progress in noise and vibration (NVH) engineering has enabled to constantly advance quality and comfort of operation and use of really any products - from automobiles to aircraft, to all kinds of industrial vehicles and machines - to the extend that for many products, supreme NVH performance has becomes part of its brand image in the market. At the same time, the product innovation agenda in the automotive, aircraft and really many other industries, has been extended very much in recent years by meeting ever more strict environmental regulations. Like in the automotive industry, the drive towards meeting emission and CO2 targets leads to very much accelerated adoption of new powertrain concepts (downsizing of ICE, hybrid-electrical...), and to new vehicle architectures and the application of new materials to reduce weight, which bring new challenges for not only maintaining but further improving NVH performance. This drives for innovation in NVH engineering, so as to succeed in meeting a product brand performance for NVH, while as the same time satisfying eco-constraints. Product innovation has also become increasingly dependent on the adoption of electronics and software, which drives for new solutions for NVH engineering that can be applied for NVH performance optimization of mechatronic products. Finally, relentless pressure to shorten time to market while maintaining overall product quality and reliability, mandates that the practice and solutions for NVH engineering can be optimally applied in all phases of product development. The presentation will first review the afore trends for product and process innovation, and discuss the challenges they represent for NVH engineering. Next, the presentation discusses new solutions for NVH engineering of products, so as to meet target brand values, while at the same time meeting ever more strict eco constraints, and this within a context of increasing adoption of electronics and controls to drive product innovation. NVH being very much defined by system level performance, these solutions implement the approach of "Model Based System Engineering" to increase the impact of system level analysis for NVH in all phases of product development: - At the Concept Phase, to be able to do business case analysis of new product concepts; to arrive at an optimized and robust product architecture (e.g. to hybrid powertrain lay-out, to optimize fuel economy); to enable target cascading, to subsystem and component level. - In Development Phase, to increase realism and productivity of simulation, so as to frontload virtual validation of components and subsystems and to further reduce reliance on physical testing. - During the final System Testing Phase, to enable subsystem testing by a combination of physical testing and simulation: using simulation models to simulate the final integration context when testing a subsystem, enabling to frontload subsystem testing before final system integration is possible. - To interconnect Mechanical, Electronical and Controls engineering, in all phases of development, by supporting model driven controls engineering (MIL, SIL, HIL). Finally, the presentation reviews examples of how LMS is implementing such new applications for NVH engineering with lead customers in Europe, Asia and US, with demonstrated benefits both in terms of shortening development cycles, and/or enabling a simulation based approach to reduce reliance on physical testing.

• 국제초고층학회논문집
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• 제7권2호
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• pp.145-151
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• 2018

Newly-designed high-rise buildings, both in China and abroad, have demonstrated new innovations from the creative concept to the creative method. from the creative concept to the creative method. At the same time, digital technology has enabled more design freedom in the vertical dimension. "Twisting" has gradually become the morphological choice of many city landmark buildings in recent years. The form seems more likely to be driven by the interaction of aesthetics and structural engineering. Environmental performance is often a secondary consideration; it is typically not simulated until the evaluation phase. Based on the research results of "DigitalFUTURE Shanghai 2017 Workshop - Wind Tunnel Visualization", an approach that can be employed by architects to design environmental-performance buildings during the early stages has been explored. The integration of a dynamic form-finding approach (DFFA) and programming transforms the complex relationship between architecture and environment into a dialogue of computer language and dynamic models. It allows the design to focus on the relationship between morphology and the surrounding environment, and is not limited to the envelope form itself. This new concept of DFFA in this research consists of three elements: 1) architectural form; 2) integration of wind tunnel and dynamic models; and 3) environmental response. The concept of wind tunnel testing integrated with a dynamic model fundamentally abandons the functional definition of the traditional static environment simulation analysis. Instead it is driven by integral environmental performance as the basic starting point of morphological generation.