• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.806-808
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• 2004

The series and parallel connection is essential for increasing power ratings of resistive type for fault current limiters. To increase voltage class, components are connected in series and to increase current level to the nominal value, they are connected in parallel. There are two ways to connect components in series and parallel. First, connected in series and then the module connects to the parallel. Second, connected in parallel and the module connects to the series. We have studied for the two ways. In this paper, we particularly investigated way to connect components in parallel first This way has the advantage of inducing effective simultaneous quench without any other devices, for example, the thing which is inducing magnetic field to the limiting and shunt resistors. And also we studied for the endurance of component which is patterned to the bi-spiral for prospective fault current. It is very important to understand this, because SFCL will use as the only device to decrease burden of circuit breaker. As experimental results, limiting component patterned to bi-spiral endures fault current up to 30kA and it works well, in parallel to series connection,

• Journal of Power Electronics
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• 제19권4호
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• pp.1000-1010
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• 2019

The use of internal-model-based linear controller, such as resonant controller, is a well-established technique for the current control of grid-connected systems. Attractive properties for resonant controllers include their two-sequence tracking ability, the simple control structure, and the reduced computational burden. However, in the case of continuous-designed resonant controller, the transient performance is inevitably degraded at a low switching frequency. Moreover, available design methods for resonant controller is not able to realize the direct design of transient performances, and the anticipated transient performance is mainly achieved through trial and error. To address these problems, the zero-order-hold (ZOH) characteristic and inherent time delay in digital control systems are considered comprehensively in the design, and a corresponding hold-equivalent discrete model of the grid-connected converter is then established. The relationship between the placement of closed-loop poles and the corresponding transient performance is comprehensively investigated to realize the direct mapping relationship between the control gain and the transient response time. For the benefit of automatic tuning and real-time adaption, analytical expressions for controller gains are derived in detail using the required transient response time and system parameters. Simulation and experimental results demonstrate the validity of the proposed method.

• 한국의상디자인학회지
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• 제23권2호
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• pp.43-52
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• 2021

This case study developed and operated "Fashion & Film" as a fashion-related liberal arts course. The class was designed to include fashion styles exhibitted in films, fashion-related PPL, fashion design through film, fashion images of movie characters, considering gender & color images expressed in movie costumes, and the history of western costumes and asian folk costumes in films. The class was counducted through various teaching methods, such as lectures, student's presentation of movie plots, and team discussions, which created a student-led class. The team presentations at the end of the term were intended to enhance the understanding of fashion through movies. The results of subjective lecture evaluation of "Fashion & Film" showed the most satisfaction with the communication with professor. Students said that it was good to understand fashion through film. They expressed a burden with the team project; however, they were satisfied with the team project outcomes. Students said that PowerPoint was used very effectively. On the other hand, there was an prevelent opinion that the content of PowerPoint and workbook did not match. To address this inconvenience, a textbook called "Fashion in Film" was published and used in the first semester of 2020. The multiple-choice evaluation showed that students were generally satisfied with the "Fashion & Film" class.

• 정보보호학회논문지
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• 제34권3호
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• pp.537-552
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• 2024

국내 원전은 방사능방재법에 의거하여 '정보시스템 보안규정'이 수립됨과 함께 조직구성부터 자산의 기술적/운영적/관리적 보안조치에 이르는 사이버보안 체계를 도입하여 운영하고 있다. 단계별 접근법, 물리적방호체계의 대안조치 등이 시도되고 있지만, 관리대상의 감소는 이루어지지 않기 때문에 현장의 한정된 인력으로 운영하기엔 보안 역량의 부담이 가중되고 있다. 본문에서는 원전 안전기능을 수행하는 A1 유형 자산에 대해 정비규정(MR, Maintenance Rule), EPRI 기술적 평가 방법론(TAM, Technical Assessment Methodology)를 활용하여 정비적인 측면과 기기 특성에 대한 측면으로 분석하였다. 이를 통해 사이버침해로 인한 자산기능의 영향을 재분석하는 방안을 제시한다.

• 한국사회복지학
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• 제43권
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• pp.106-130
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• 2000

When parents as primary care takers to the mentally disabled adult are no longer taking care of their care-needed offsprings because of their own death or illness, instead themselves. who take care of their offsprings with the mental disability? Therefore, 'permanency planning' is very important for reduction of parents' care burden and social integration of mentally disabled adults. Accordingly, this study aims to find out factors which are related to permanency planning for adults with the mentally disability For the purpose of the study, 192 parents of the adult with the mental illness and mental retardation were conducted a survey regarding type of permanency planning, and its related factors including social functioning level of the mentally disabled, care burden, parents' self-perception of being aged, help from offspring without mental disability, social support, and financial ability. Furthermore, this study examined correlation between these factors and residential planning. Results obtained by the study were as follows: 1) 51% of the parents are having a plan for institution and most parents want other family member to take care for financial planning for their mentally disabled offsprings. 2) As a result of multiple regression for finding out factors which affect parents' permanency planning, social functioning level of the mentally disabled, parents' self-perception of being aged, help from offspring without mental disability, social support, and financial ability were statistically significant influenced factors, which has 23.3% of explanatory power. 3) As a result of step-wise multiple regression, financial ability, parents' self-perception of being aged, and help from offspring without mental disability were the most powerful influenced factors for permanency planning. 4) In case of having a plan for residential types-which are institution and community living-, parents who have a plan for the mentally disabled offsprings' future residence as community living than institution have the offsprings with more social functioning and also have more help from offspring without mental disability. Therefore, this study concluded that welfare policy for mental health and the handicapped which secure various types of community living facilities and income security is strongly needed. At the same time, mental health profession is needed to have more active interest and intervention for permanency planning for their adult clients and parents.

• 대한간호학회지
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• 제29권3호
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• pp.639-655
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• 1999

An explanatory design was employed to identify the relationship of physical, emotional & social readjustment and social support of post hospitalized stroke patients and their caregivers. A convenient sample of 254 patients who given follow-up care at the outpatient department after discharge and 225 caregivers were recruited. Mental Status Questionnaire (MSQ), Social Support Inventory Stroke Survivors (SSISS), Illness intrusiveness(II), Instument Activity of Daily Living(IADL), Center of Epidemilogic Studies-Depression(CES-D), social activity and caregiver burden were used for measurement in this study. Results showed patient's physical level measured by IADL and psychological level measured by depression were high. But social activity was low. Cognitive function, depression & social activity were not significantly different by the posthospitalized period, but IADL was. The source of professional support was mostly the physician at the outpatient department. The family support was found significantly related to patient's depression & social activity and caregiver's subjective burden. Professional support was found significantly related to patient's IADL & depression. Illness intrusiveness as a mediating variable was a sig nificantly predicting power on patient's IADL & depression. The path analysis was used to identify the variables to predict the physical, emotional, and social status of patients. As a result, patient's age, cognitive function, illness intursiveness and professional support significantly predicted the level of IADL ; patient's cognitive function, illness intrusiveness and family support significantly predicted the level of depression ; and patient's age and family support significantly predicted the level of social activity of posthospitalized stroke patients. Based upon these results, the rehabilitation programs to reduce the illness intrusiveness and improve cognitive funtion were recommended for the readjustment of the stroke patients. This model of the readjustment of the posthospitalized stroke patients is recommended as the framework for care of the stroke patients.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2014년도 하계학술대회
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• pp.157-159
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• 2014

In this paper, we introduce SlimSRP, an ultra-low-power digital signal processor (DSP) solution for mobile audio and voice applications. So far, application processors (APs) have taken charge of all the tasks in mobile devices. However, they have suffered from short battery life problems to deal with complex usage scenarios, such as always-on voice trigger with continuous audio playback. From extensive analysis of audio and voice application characteristics, SlimSRP is designed to relive the performance and power burden of APs. It employs three-issue VLIW architecture, and the major low-power and high-performance techniques include: (1) an optimized register-file architecture friendly for constants generation, (2) a powerful instruction set to reduce the number of register file accesses and (3) a unique instruction compression scheme that contributes to saved memory size and reduced cache miss. An implementation of SlimSRP runs at up to 200MHz and the logic occupies 95K NAND2 gates in Samsung 28LPP process. The experimental results demonstrate that a MP3 decoder application with a 128kbps 44.1kHz input can run at 5.1MHz and the logic consumes only 22uW/MHz.

• 한국안전학회지
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• 제32권3호
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• pp.160-171
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• 2017

US national research laboratories developed the first Vital Area Identification (VAI) method for the physical protection of nuclear power plants that is based on Event Tree Analysis (ETA) and Fault Tree Analysis (FTA) techniques in 1970s. Then, Korea Atomic Energy Research Institute proposed advanced VAI method that takes advantage of fire and flooding Probabilistic Safety Assessment (PSA) results. In this study, in order to minimize the burden and difficulty of VAI, (1) a set of streamlined VAI rules were developed, and (2) this set of rules was applied to PSA fault tree and event tree at the initial stage of VAI process. This new rule-based VAI method is explained, and its efficiency and correctness are demonstrated throughout this paper. This new rule-based VAI method drastically reduces problem size by (1) performing PSA event tree simplification by applying VAI rules to the PSA event tree, (2) calculating preliminary prevention sets with event tree headings, (3) converting the shortest preliminary prevention set into a sabotage fault tree, and (4) performing usual VAI procedure. Since this new rule-based VAI method drastically reduces VAI problem size, it provides very quick and economical VAI procedure. In spite of an extremely reduced sabotage fault tree, this method generates identical vital areas to those by traditional VAI method. It is strongly recommended that this new rule-based VAI method be applied to the physical protection of nuclear power plants and other complex safety-critical systems such as chemical and military systems.

• 한국항행학회논문지
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• 제20권1호
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• pp.86-92
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• 2016

최근 사람이 다수 붐비는 지역에 스마트 폰이나, 태블릿 등을 바로 충전할 수 있는 태양광 모듈이 설치되어 서비스를 제공하고 있다. 하지만 설치비용이 높아 이용인원이 적은 지역에 설치 할 경우 비용측면에서 부담이 되며, 협소한 지역에는 설치가 어려운 문제점이 존재한다. 본 논문에서는 이와 같은 문제를 해결하기 위해 국가에서 제공하는 데이터와, 실제 환경에서 수집한 데이터를 이용하여 각 지역에 해당 서비스를 제공받는 사람에 대한 정보를 분석 한 후 대기시간 및 태양광 충전시간을 고려하여 환경에 맞는 최적의 전력을 수집 및 제공하는 시스템을 제안하였다. 실험결과 수집전력이 충전전력량보다 상회하여 충전이 지연되지 않았으며, 약 95분경에 스마트 폰의 전력을 모두 충전할 수 있음을 확인하였으며, 버스 대기시간인 10분에서 20분 사이에 스마트 폰이 한 대일 경우 약 50%가량을 충전할 수 있으며, 여러 대일 경우 약 20%가량을 충전할 수 있음을 확인하였다.

• 한국산학기술학회논문지
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• 제17권4호
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• pp.296-302
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• 2016

콘크리트의 내구성 저하로 인한 균열의 보수 및 보강에 소요되는 비용은 콘크리트 구조물의 유지비용 증대로 연결되어 균열발생 저감에 대한 연구가 요구되고 있다. 특히, 전력공급용 시설인 전력구의 경우 지하 매설물이므로 보수 및 보강은 경제적으로 큰 부담이 된다. 그러므로 지하매설 전력구의 경우 효과적인 균열 저감 방안이 설계 초기단계부터 요구되어진다. 본 연구는 전력구용 저수축 콘크리트 제조를 위한 수축저감제 개발의 일환으로 수축저감제 사용 콘크리트의 초기 강도 개선을 위해 TEA를 검토하였다. 검토결과, TEA를 수축저감제의 3% 사용할 경우 조기 강도가 크게 개선되었으며, 수축저감 효과도 우수한 것으로 확인되었다. 또한, TEA 3 %에 수축저감제 2.0 % 혼합하여 적용하였을 경우 압축강도 특성 및 건조수축 길이변화 실험결과에서 가장 우수한 것으로 나타나 수축저감제로서의 가능성을 확인하였다. 추후 수축저감제의 범용적인 적용성 검토를 위하여 수축저감제의 사용재료 변화 등에 대한 다양한 재료변수 요인 검토를 통하여 수축저감제의 성능 검토가 필요할 것으로 사료된다.