• Journal of Computing Science and Engineering
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• 제5권4호
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• pp.324-330
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• 2011

To avoid collisions, IEEE 802.11 medium access control (MAC) uses predetermined inter-frame spaces and the random back-off process. However, the retransmission strategy of IEEE 802.11 MAC results in considerable time wastage. The hidden node problem is well known in wireless networks; it aggravates the consequences of time wastage for retransmission. Many collision prevention and recovery approaches have been proposed to solve the hidden node problem, but all of them have complex control overhead. In this paper, we propose a fast retransmission scheme as a recovery approach. The proposed scheme identifies collisions caused by hidden nodes and then allows retransmission without collision. Analysis and simulations show that the proposed scheme has greater throughput than request-to-send and clear-to-send (RTS/CTS) and a shorter average waiting time.

• 대한간호학회지
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• 제19권1호
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• pp.92-98
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• 1989

Concept analysis is a formal linguistic exercise to determine certain defining attributes. The basic purpose of concept analysis is to clarify ambiguous concepts in a theory, and to propose a precise operational definition which reflects its theoretical base (Walker, 1983, 27~28). In later life, elderly people are faced with various psychological problems such as depression, and lowered self-esteem for these psychological problems of the elderly. Reminiscence has been studied as an effective therapeutic measure by gerontologists and psychologists. It is considered to have potential as an effective nursing intervention with geriatric clients. The purpose of this paper was to explore the feasibility of adopting reminiscence as a nursing intervention through analysis of the concept. The concept can be defined as follows : Reminiscence is thinking and talking about one's past with or without a specific purpose. It is a composite mental process which involves psychological, emotional, and social interactional aspects. The defining attributes of reminiscence are : 1. Thinking about past experiences which are meaningful to oneself. 2. It includes the emotional aspect of past experiences. 3. It occurs with or without specific purposes. 4. It is communicated to others by means of language and the subject has the feeling of being heard. In regard to the consequences of reminiscence, it is expected to contribute to psychological adaptation by providing a sense of self-fulfillment and self-achievement, promoting the discovery of the meaning of life, decreasing depression, and overcoming guilt feelings and conflict about one's past. However, if the past is regarded as a total failure, it may be harmful to the psychological well-being of the subject.

• 한국컴퓨터정보학회논문지
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• 제10권5호
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• pp.227-236
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• 2005

네트워크 이동성 기본 솔루션(NEMO basic solution)의 비 경로 최적화의 문제점을 해결하기 위한 방안 중 하나로 HPD(Hierarchical Prefix Delegation) 프로토콜이 있다. 그러나 HPD는 미시적 이동성에 대한 지원을 하지 못하므로 이동네트워크노드(MNN)가 접촉점을 변경할 때마다 MIPv6 프로토콜에서와 같이 HA(Home Agent)와 통신노드(CNs)로 BU(Binding Update) 메시지를 보내야하는 문제점을 갖는다. 본 논문은 HPD에 HMIPv6 프로토콜 개념을 적용하여 nested MEMO에서의 미시적 이동성을 효과적으로 지원하는 알고리즘을 제안하였다. 이동네트워크노드는 MAP(Mobility Anchor Point) 영역 안에서 위치변경 시 가까운 곳에 위치한 MAP으로만 BU를 보냄으로써 핸드오프 과정에서 발생하는 서비스 중단이나 신호 부하를 감소시켜 HPD에서의 한계를 극복하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.129-136
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• 2005

The deterministic analysis method has generally used to evaluate the slope stability and it evaluates the slope stability with decision value that is a representative value of design variables. However, one of disadvantages in the deterministic approach is there is not able to consider the uncertainty of soil strength properties, even though it is the biggest influential parameter of the slope stability. On the other hand, the limit state design(LSD) can take a consideration of uncertainties and computes both the reliability index and the probability of failure. LSD method is capable of overcoming the disadvantages of deterministic method and evaluating the slope stability more reliably. In this study, both the mean value and standard deviation of the internal land's representative soil strength properties applied to process the LSD method. The major purpose of this study is to gauge the general applicability of the limit state design in soil slope and to weigh the comparative validity of the proposed partial safety factor. In order to reach the aim of this study, the partial safety factor and resistance factor which totally satisfied the slope's overall safety factor were calculated by the load and resistance safety factor design (LRFD).

• Fashion, Industry and Education
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• 제14권2호
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• pp.60-69
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• 2016

Visual literacy, a key element of a design portfolio, is achieved by communicating a consistent visual aesthetic with respect to design elements, design principles and individual style. Yet, students often feel challenged in articulating their personal aesthetic or design philosophy in order to create a unifying design identity within a body of artifacts. This paper shares some best practices on overcoming this challenge through students' engagement in self-reflection and identity formation processes. The implemented innovative strategy in a senior-level portfolio development course for apparel designers involved four different phases: 1) one-on-one meetings to self-reflect on previous design work, 2) selection and revision of artifacts, 3) peer-review and critiques of revised portfolio artifacts, and 4) development of a final ePortfolio to showcase a unified design identity. It was evident that recording students' initial self-reflection in the form of a metacognitive oral report encouraged and motivated identity development in their portfolio. Further, students expressed their satisfaction in the ability to participate in the selection process of artifacts by self-reflecting about what they wanted to highlight about themselves and why. Overall, student outcomes from this strategy exceeded expectations and the portfolios developed were successful in creating a cohesive design identity.

• 컴퓨터교육학회논문지
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• 제4권2호
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• pp.165-178
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• 2001

인터넷의 보급으로 확산되고 있는 가상교육이 교육의 효과를 내기 위해서는 적절한 강의평가가 요구된다. 웹 기반 교육에서는 설문지를 이용한 평가가 가장 보편적으로 이루어지고 있는데, 이는 간단한 텍스트 형태의 설문지나, CGI나 ASP를 이용하여 인터넷에서 바로 설문에 응할 수 있는 형태 등으로 비교적 다양하게 구성되어 있다. 본 논문에서는 현재 인터넷상에서 이루어지고 있는 설문 시스템을 비교 분석하여 그 특징과 제한점을 알아본 후 그 제한점을 극복할 수 있도록 ASP를 이용하여 설문지를 인터넷상에서 편리하게 만들 수 있고 만들어진 설문을 관리하며 그 설문을 통해 나타난 결과를 교육자에게 피드백하는 시스템을 설계 및 구현한다.

• 한국전자통신학회논문지
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• 제10권7호
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• pp.769-774
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• 2015

사물인터넷의 하부 구조로 센서네트워크는 네트워크의 신뢰성이 중요한 이슈이다. 센서네트워크의 각 노드는 제한된 메모리와 파워로 인해 데이터의 신뢰성을 향상시켜야 한다. 본 연구에서는 센서 노드가 생성한 데이터를 이웃 노드에 복제하는 기법을 제안한다. 네트워크의 신뢰성을 향상시키기 위해서 주변 노드의 메모리 및 파워 잔량이 높은 노드에 사본을 저장하는데 1 홉 이상의 노드들에도 저장하여 공간적인 재해에도 대비한다. 실험을 통해 적절한 사본을 유지하는 것은 네트워크의 수명에 부정적인 영향을 미치지 않으면서도 사물인터넷의 신뢰성을 향상시킴을 확인하였다.

• 가정과삶의질연구
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• 제20권5호
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• pp.13-26
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• 2002

The purpose of this study was to reduce the unemployed housewives' stress and to seek proper strategies to cope with the stress by understanding stress of urban unemployed housewives' caused by financial management. The survey for this study was conducted in the capital city of Korea, Seoul and other major cities. The subjects included housewives in these areas who currently cohabited with their spouses and had at least on child or more. The preliminary and main survey questionnaires were distributed between November 12, 2001 and February 27, 2002. The results of the study were to establish an appropriate policy in order to improve the economic welfare and to develop strategies or related programs in order to overcome financial crisis in the family economy. the major findings were as follows: (1) The stress level of urban unemployed housewives caused by the financial management showed an average of 2.64 out of 5.0 and the level of utilizing strategies to cope with the stress indicated an average of 2.79 out of 5.0 (2) There were significant relationship between the stress caused by the financial management and the strategies of overcoming the stress indicated positive correlation(r=.378). (3) Relative contributor among independent variables to cope with stress was analysed and at the second phase in the process of the analysis, the subjective variables appeared to be significant variables to contribute to cope with the stress.

• 한국정보시스템학회지:정보시스템연구
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• 제27권1호
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• pp.1-20
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• 2018

Purpose The purpose of this study is to identify the determinants of non-use and the dynamic nature of non-use by the qualitative research methodology, grounded theory methodology, as part of identifying the nature of non-use. Design/methodology/approach We applied the grounded theory methodology to a total of 23 college students, including non-users who are not currently using them, users with low intention to use them, and users with high intention to use. We extracted the codes related to the use and proposed the non-use dynamics conversion process based on the coding results. Findings First, the use of information technology can also promote the frequency of use, but can also lead to the use of negative attitudes which would fall in the state of non-use. Second, the user may have both positive and negative attitudes toward the current information technology. Third, if usage is dominated by habits, it is not so easy to change persistent use into an unused state. Fourth, factors that determine the use of specific information technology can be a factor in determining nonuse. This study has contributed to understand the essence of non - use as well as the nature of use, overcoming limitations of quantitative research approach and confirming possibility of grounded theory method in information system research.

• 한국소음진동공학회논문집
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• 제26권3호
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• pp.323-330
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• 2016

This paper describes real-time unbalance moment compensation method for line of sight(LOS) stabilization control systems. The factors of system inertia, frictions and unbalance moment affect the control accuracy of drive systems that are equipped to on the move(OTM) platforms requiring LOS stabilization function. In case of the unbalance moment among those factors is continuously changed as variation of relative angle between gravity vector and drive torque vector. Then, consideration of the effect in real-time is very complicate. Therefore, its effect should be designed to be minimized, however, designing it almost zero is impossible in real condition. In other words, it is hard to achieve target performance overcoming stability issue of highly unbalanced systems. To solve these problems, this paper proposes calculation method of unbalance moment by using measured sensor data for LOS stabilization control and its use for control compensation. Also, kinematical converting process and control structure for compensation are explained. The effectiveness of the proposed method as variation of unbalance moment is verified under simulation circumstance modeled by assuming LOS control system with 2-axis gimbal structure.