• KIPS Transactions on Computer and Communication Systems
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• v.3 no.11
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• pp.393-402
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• 2014

We have experienced an explosive increase of the IoT(Internet of Things) technology based devices including smart phones and the wireless communications. Also the growing power consumption in IEEE 802.11 WLANs(Wireless LANs) driven by these dramatic increases in not only mobile users and but also wireless APs(Access Points). To reduce the power consumption, this paper proposes a wireless AP power saving algorithm, which minimizes the transmission power without decrease the transmission and carrier sense ranges. A wireless AP which is use in our algorithm checks its own original coverage periodically for whether there is a new STA(Station) or not when its transmission power is decreased. Moreover, if there are no signaling message to connect the wireless AP, it changes its operation mode Wake-up to sleep. A Result shows that the proposed AP algorithm can reduce the total power consumption of the wireless AP approximated 18% and 35% compared to the conventional wireless AP with and without the existing power saving algorithm, respectively.

• The Korean Journal of Emergency Medical Services
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• v.13 no.3
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• pp.71-76
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• 2009

서론(Introduction) : 의학 시뮬레이션(medical simulation)은 교육생 학습과정에서 내재된 위험이 환자에게 가해짐 없이 교육생이 실제적인 환자 상황을 경험할 수 있게 하고 여러 다양한 임상내용이 포함한 상황에 적용될 수 있다. 시뮬레이션 기술의 사용은 의학교육(medical education), 인증서(certification), 면허교부(Licensure)와 의료의 질 형성에 큰 잠재력을 가지고 있다. 복강경 수술, 내시경검사, 전문심장구조술, 응급기도관리와 외상소생을 포함한 다양한 임상시술의 수행에서 시뮬레이션이 교육생의 술기를 달성하고, 측정하고, 유지하는 유효성을 증명하였다 컴퓨터로 조절되는 시뮬레이터는 맥박, 혈압, 호흡, 대화가 가능하고, 중증질환 또는 외상환자의 치료에 필요한 같은 인명구조 시술을 수행할 수 있다. 의학 시뮬레이션은 의사, 간호사, 응급구조사와 응급 진료를 필요로 하는 환자를 치료하는 사람에게 필요하다. 최신 전문심장구조술 과정수업은 전통적인 강의와 제한된 팀 상호작용이 포함된 이틀 과정이다. 우리는 비 영어권 국제 응급구조학생의 전문심장구조술 술기능력을 알아보고, 그것을 미국 응급구조학생과 비교하고자 한다. 목적(Objective) : 이 연구의 목적은 다양한 전문심장구조술 증례 시나리오를 가진 의학 시뮬레이터를 이용하여 미국과 한국의 응급구조 학생의 능력을 비교하는 것이다. 시행 장소(Site Location) : 이 연구는 한국 제주도에 위치한 제주한라대학 스토니브룩 응급의료교육원에서 진행되었다. 학생들의 평가는 스토니브룩에 위치한 스토니브룩 대학 의료원의 한 명의 평가자(Dr. lee)에 의해 수행되었다. 방법(Methods) : 15명의 한국 응급구조학생들은 세 팀으로 무작위로 선정하였다. 5명이 한 팀이 되어 같은 증례의 시나리오를 받았다. 세 가지 시나리오는 : 첫째, 천식지속상태(Status asthmaticus), 둘째, 긴장기흉을 동반한 만성폐쇄성폐질환(COPD with tension penumothorax) 그리고 마지막으로 메가코드(megacode)를 가진 심정지 이다. 세 팀을 각각 그리고 기본인명구조술(BLS)과 전문심장구조술(ACLS)과정을 마친 미국 응급구조학생들과 비교하였다. 15명의 미국 응급구조학생들 또한 세 팀으로 무작위로 선정하였다. 이 응급구조 학생들은 플러싱병원 의료원 소속으로 그곳에서 이 연구에 참여할 뿐만 아니라 지속적인 의학교육(CME)이수를 받았다. 이들에게도 같은 세 가지 증례의 시나리오가 주어졌고 Dr lee는 총 여섯 팀을 평가하였다(한국 세 팀과 미국 세팀). 결과(Results) : 양 국가의 모든 15명의 학생이 의학시뮬레이터를 사용하여 전문심장구조술 메가코드시험을 포함한 시험에 모두 통과하였다. 비록 학생들을 무작위로 세 팀으로 나누었지만 한 팀이 이 모든 세 증례에서 다른 팀보다 뛰어났다. 제주한라대학 2번 팀은 더 나은 기도관리, 리듬인식과 임상술기를 가진 모든 중요한 활동을 얻기에서 우수했다. 그들은 핵심요구사항을 90% 이상 충족시겼다. 한국의 2번팀(G2K)은 메가코드에서 기도개방, 호흡평가, 순환징후 그리고 흉부압박수와 같은 신체검진 술기에서도 탁월했다. 게다가 다른 팀과 비교 시 리듬인식, 약물지식과 임상술기에서도 높은 점수를 받았으며 2번팀(G2K)이 6팀 중에 가장 뛰어나게 역활수행을 하였다. 결론(Conclusion) : 이 비교 연구에서 한국학생과 미국학생간에 전문심장구조술 메가코드 시험의 통과율에는 차이가 없었다. 그러나 미국학생은 세 팀 사이에 더 적은 변이로 더 일괄된 점수를 받았다. 한국학생들도 모든 세 가지 증례를 통과하였지만 이 세 팀은 미국학생 팀보다 점수에서 더 큰 변이를 보였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.2
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• pp.13-23
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• 2016

Many traffic centers are highly hesitant in employing existing Automatic Incident Detection Algorithms due to high false alarm rate, low detection rate, and enormous effort taken in maintaining algorithm parameters, together with complex algorithm structure and filtering/smoothing process. Concerns grow over the situation particularly in Freeway Incident Management Area This study proposes a new algorithm and introduces a novel concept, the Displaced Flow Index (DiFI) which is similar to a product of relative speed and relative occupancy for every execution period. The algorithm structure is very simple, also easy to understand with minimum parameters, and could use raw data without any additional pre-processing. To evaluate the performance of the DiFI algorithm, validation test on the algorithm has been conducted using detector data taken from Naebu Expressway in Seoul and following transferability tests with Gyeongbu Expressway detector data. Performance test has utilized many indices such as DR, FAR, MTTD (Mean Time To Detect), CR (Classification Rate), CI (Composite Index) and PI (Performance Index). It was found that the DR is up to 100%, the MTTD is a little over 1.0 minutes, and the FAR is as low as 2.99%. This newly designed algorithm seems promising and outperformed SAO and most popular AIDAs such as APID and DELOS, and showed the best performance in every category.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.51-62
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• 2012

According to the Lighthill and Whitham's shock wave model, a shock wave exists even in a homogeneous speed condition. They referred this wave as unobservable- analogous to a radio wave that cannot be seen. Recent research has attempted to identify how such a counterintuitive conclusion results from the Lighthill and Whitham's shock wave model, and derive a new asymptotical shock wave model. The asymptotical model showed that the shock wave in a homogenous speed traffic stream is identical to the ambient vehicle speed. Thus, no radio wave-like shock wave exists. However, performance tests of the asymptotical model using numerical values have not yet been performed. We investigated the new asymptotical model by examining the implications of the new model, and tested it using numerical values based on a test scenario. Our investigation showed that the only difference between both models is in the third term of the equations, and that this difference has a crucial role in the model output. Incorporation of model parameter${\alpha}$ is another distinctive feature of the asymptotical model. This parameter makes the asymptotical model more flexible. In addition, due to various choices of ${\alpha}$ values, model calibration to accommodate various traffic flow situations is achievable. In Lighthill and Whitham's model, this is not possible. Our numerical test results showed that the new model yields significantly different outputs: the predicted shock wave speeds of the asymptotical model tend to lean toward the downstream direction in most cases compared to the shock wave speeds of Lighthill and Whitham's model for the same test environment. Statistical tests of significance also indicate that the outputs of the new model are significantly different than the corresponding outputs of Lighthill and Whitham's model.

• Korean Journal of Family Social Work
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• no.43
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• pp.61-85
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• 2014

The aim of this study is to examine how labour transition of female householders is proceeded, and to identify mechanisms that cause them to be excluded from labor market. For this, thirteen lone mothers who have had labor experience in the market, while raising children were interviewed. This qualitative case study was proceeded by way of participants' interviews and questionnaires. Finding shows, impoverished lone mothers were horizontally moving incessantly on second labor market. As poverty worsens by years, poor lone mothers tend to be more dependant on the government's support and to transit downward to work-poor labor market. The unprivileged women were excluded from multi-dimentions: market structure, social relations and gender norms. The sex-segmental and human capital-oriented market has excluded women who gave up their career for caring. Female breadwinners were frequently excluded from social relations and opportunities for labor due to their stigma. sometimes they were self-excluded from the market for they had to care for their children. In conclusion, suggestions are given to enhance qualities of lone mother's lives and help them exit from poverty. It is necessary to implement positive labor policy with labor flexibility and stability and to practice socialization of care as care support system is very important for maintaining their jobs. Above all, social awareness of gender role must be changed.

• (The)Korea Educational Review
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• v.23 no.1
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• pp.113-138
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• 2017

Questions of why, what, and how represent the new perspective on goal construct. This paper proposed a novel approach toward the goal construct as a dynamic decision-making process. A number of researchers have agreed that goals initiate and sustain human motivation. In spite of the consistency in emphasis on goals, there are apparent inconsistencies in definitions of goal construct across theories and research. These inconsistences hinder interdisciplinary communication about goal construct, which in turn leads to jingle-jangle fallacy. Therefore, on the basis of systematic literature review, I defined the goal construct as a multifaceted and hierarchical decision-making process to structure desired end-states. The first process is generating goals, which can be also called "why" process. During this phase, individuals generate cognitive schema about general direction of desired end-states based on the conscious and nonconscious interpretation of subjective experience. The second process is goal setting, which can be called "what" process. Here, individuals clarify contents of multiple goals and structure hierarchy and priority of them. The last process is implementing goals, "how" process. This process contains decision making about whether he/she decides to implement the goal or not and how to execute goal-directed behaviors. In the last section of this paper, I tried to suggest several practical applications of this new perspective for adolescents, who struggle with why-what-how to have goals in learning context.

• Review of Culture and Economy
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• v.17 no.2
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• pp.81-102
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• 2014

As carbon dioxide, the main greenhouse gas, is generally emitted by vehicles, the development and distribution of electric cars is important for the sustainability of environmentally-friendly tourism, especially in national parks. National parks in Korea, however, still see the use of traditional vehicles powered by internal combustion engines in the handling of visitors and the transportation of goods and staff. Such engines being the cause of environmental problems such as exhaust emission and noise pollution, the introduction of electric cars in national parks is needed. This study aims to analyze the economic value of electric cars in national parks as well as contribute to the development of the Green Transportation model in tourism destinations. The study used a logit model to estimate the willingness to pay for the introduction of electric cars in national parks. Adults over the age of twenty, with gender and age apportioned equally, were surveyed using questionnaires that included dichotomous as well as demographic questions. The findings show that the amount an individual is willing to pay for the purpose of environmental conservation is 3,948 won, while the value the national parks would derive from the use of electric cars is 56,138,130,000 won. The introduction of electric cars in national parks is expected to offer both direct and indirect benefits while helping to improving the environment of the national parks by eliminating exhaust emission and noise. This introduction would also be a response to climate change that can be taken by society as a whole.

• Journal of Korean Philosophical Society
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• v.117
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• pp.85-111
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• 2011

Topics with which chis paper deals are as following; (1)Zizek's interpretation of Rothko's painting, (2)Lacan's gaze and picture, (3)the real as object a, (4)primal jouissance and death-drive, (5)a new identity of man-emptiness in Zizek, (6) existential level and existential conflict, (7)a variety of meanings of emptiness, (8)transpecsonal drive and meditation, (9) the different Real-Emptiness, (10)Rochko's painting and transpersonal drive.

• Korean Journal of Social Welfare Studies
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• v.43 no.1
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• pp.389-411
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• 2012

A new era of research has focused on examining the growth of change in drinking problems among the elderly. Thus, the purpose of the present study was two fold: (1) to investigate trajectories of drinking problems(CAGE) among the Korean elderly(age$${\geq_-}65$$); and (2) to identify the predicting factors for the intercept and the slope of alcohol problems using multi-level growth curve model. Data come from three waves(1st wave(2006)~3rd wave(2008) of the Korea Welfare Panel(KWP) study. The results indicated that the levels of drinking problems decreased over time and that age, gender, marital status, religion, poverty, self-rated health, and social relationship satisfaction were associated with the baseline CAGE. Further analysis showed that social relationship satisfaction affected the declining slope of drinking problems over time. Specifically, among those who satisfied social relationship, there was a sharp decline of CAGE over time. Overall findings highlight the importance of developing and implementing effective alcohol prevention programs for the elderly in the community settings to mitigate the harmful effects of various psycho-social stressors. Especially, programs to maintain and form healthy social support network are suggested as critical interventions for prevention as well as recovery of alcohol problems in late life.

• Journal of Korea Water Resources Association
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• v.52 no.spc2
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• pp.801-810
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• 2019

This study analyzes the impact on geomorphic changes downstream due to alternate bars developed weir upstream through laboratory experiments. The disturbance, such as a spur in the side wall, of the flow at the inlet of the channel triggers the development of alternate bar upstream at the beginning of the experiment, and gradually moved downstream with keeping their shapes over time. The bed in the downstream of weir in the mid of channel scoured due to the scarcity of sediment inflow because weir upstream traps it. Moreover, bar migration speed decreases as the bars approaches to the weir with time. However, as time increases, the alternate bars upstream migrate over the weir, and sediment in the eroded bed of the weir downstream are deposited. The phase of the bar upstream changes oppositely after passing through the weir. The phase of the bar downstream changes rapidly as the shape of alternate bar is clear upstream, which is affected by the strong disturbance. The phase of bar changes, and the bar migration speed decreases gradually with time, and finally stopped due to forcing effects on the bar by the disturbance. The faster the reaction of alternate bar with a long spur, the larger the bar height formed downstream and the shorter the bar length. This means that the larger the forcing effect of bar, the more it affects the bar migration. In addition, although the size of the alternate bar increases over time, the bar doesn't migrate downstream and a forced bar is generated.