• 전기전자학회논문지
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• 제22권4호
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• pp.1195-1201
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• 2018

본 논문은 인간의 신체활동에 있어서 뇌의 신호가 연결된 근육으로 정보를 제공하고 받아오는 과정에서 유의미한 결과를 나타내는지에 관한 관계를 해석한다. 사람의 의식적 활동은 활동에 필요한 근육의 동작을 위하여 뇌로부터 생성된 전기신호의 전달에 의해 가능해 진다. 근육의 활성정보를 가지고 있는 근전도 신호는 근육활성화의 결과를 전기적인 신호로 출력하는데, 이 출력은 보통 근육의 수축과 이완에 따른 근육활성 정보를 출력한다. 본 연구에서는 이런 뇌전도와 근전도를 실시간으로 추출하여 데이터를 획득하고, 데이터 분석을 통해 눈으로 쉽게 확인하기 어려운 두 신호간의 관계를 분석하는데 목적이 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권6호
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• pp.2204-2224
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• 2021

This paper studies secure wireless transmission from a multi-antenna transmitter to a single-antenna intended receiver overheard by multiple eavesdroppers with considering the imperfect channel state information (CSI) of wiretap channel. To enhance security of communication link, the artificial noise (AN) is generated at transmitter. We first design the robust joint optimal beamforming of secret signal and AN to minimize transmit power with constraints of security quality of service (QoS), i.e., minimum allowable signal-to-interference-and-noise ratio (SINR) at receiver and maximum tolerable SINR at eavesdroppers. The formulated design problem is shown to be nonconvex and we transfer it into linear matrix inequalities (LMIs). The semidefinite relaxation (SDR) technique is used and the approximated method is proved to solve the original problem exactly. To verify the robustness and tightness of proposed beamforming, we also provide a method to calculate the worst-case SINR at eavesdroppers for a designed transmit scheme using semidefinite programming (SDP). Additionally, the secrecy rate maximization is explored for fixed total transmit power. To tackle the nonconvexity of original formulation, we develop an iterative approach employing sequential parametric convex approximation (SPCA). The simulation results illustrate that the proposed robust transmit schemes can effectively improve the transmit performance.

• 대한임상전기생리학회지
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• 제5권2호
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• pp.61-72
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• 2007

INTRODUCTION: Local heat and cold application has been frequently used as means of muscle relaxation and blood circulation or reinforcing muscle strength, relaxing muscle tension in clinical situation. In particular, it has been known that long-term heat and cold application for relaxing muscle tension inhibits muscle spasticity or tension. But, it has been rarely reported that what influences of heat and cold application on activation of muscle action potential. Therefore, this study aims to analyze surface temperature and electromyography activities according to the heat and cold application. METHODE: Subjects of this research were 10 normal men and women (5 men, 5 women). Hot pack and cold pack was applied to vastus medialis muscle of thigh and rectus femoris muscle for 20 min. Surface temperature of vastus medialis muscle and rectus femoris muscle was measured, knee joint of subjects was in $45^{\circ}$ flexion, sitting on a chair, maximal isometric contraction was induced, surface electromyography (sEMG) signals were collected and root mean square (RMS) and median frequency (MOF) were analyzed. All measurements were conducted before and immediately after experiment, 10 min., 20 min. and 30 min. after experiment. Data were analyzed with SPSS 12.0 program, comparison of changes in superficial temperature and sEMG signals through repeated measurement was conducted with repeated measures ANOVA and significance level $\alpha$ was 0.05. RESULTS: Changes of surface temperature of vastus medialis muscle according to cold application were radically decreased immediately after application, but it was recovered after 30 min. of application and it showed significant difference (F4. 36=72.216, P<0.001). Surface temperature of rectus femoris also showed radical decrease immediately after application, but it was recovered after 30 min. of application and showed significant difference (F4. 36=88.930, P<0.001). Changes of surface temperature of vastus medialis muscle according to heat application were radically increased immediately after application, but it was recovered after 30 min. of application and it showed significant difference (F4. 36=27.267, P<0.001). Surface temperature of rectus femoris also showed radical decrease immediately after application, but it was recovered after 30 min. of application and showed significant difference (F4. 36=19.774, P<0.001). Changes of sEMG by heat and cold application were no statistical difference. Surface temperature of skeletal muscle after heat and cold application showed significant change for 30 min., but it was found that increase or decrease of surface temperature had not great influence on sEMG activities.

• 한국관광식음료학회지:관광식음료경영연구
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• 제12권1호
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• pp.79-110
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• 2001

Tourist Destination is based on tourism attractions. Components of Tourism attraction are included tourism resources, entertainment facilities, transportation, accommodation, infrastructure, assistance facilities & service, hospitality, information facilities & service, and retailing & service. Tourism resources of them is the key to determine destination development pattern, because tourism attraction that attract tourists is based on tourism resources. Therefore, there are need to study what is tourism attraction of destination at the view of tourists and what is destination development pattern based on it to develop tourism attraction that is able appeal tourists. The purpose of this study is to examine what effect of tourism attraction affects destination development pattern. This study defined Haeundae, Kwanganri, Songjung, Taejongdae in Pusan, Korea as research areas. Research data were collected from 300 respondents by a simple random sampling method. A final 284 usable questionaries were used for empirical analysis after data purification process. Reliability and validity of the scale on the tourism attraction, destination image, and facility needs have been evaluated using Cronbach $\alpha$, item-total correlations. This study analyzed the factors of the tourism attraction and destination images. The result obtained that tourism attraction is divided relaxation attraction, local activity attraction, culture . nature attraction and touring circuit attraction, and destination image is divided culture . urban attractiveness, touring attractiveness, local . stay attractiveness, convenience of travel and relativeness for destination investigated. ANOVA and regression (stepwise) were used to test hypotheses. Based on the results of hypotheses testing, major findings of the empirical research are as follow : 1. The tourism attraction and destination image are significantly different, but facility needs are not significantly by destinations (e. g. Haeundae, Kwanganri, Songjung, Taejongdae) . 2. Destination development pattern is a(fact by the tourism attraction in partial. In case of Haeundea, relaxation attraction take effect partially spa, history and marine/spa tourism. 3. The destination development pattern is influenced by the destination image in partial. In case of Kwanganri, the natural . activity attractiveness and urban tourism images have been found as influential factors that affect marine tourism. 4. The destination images are influenced the physical attributes in literature review, but the destination image are taken effect partially the tourism attraction in this study. 5. Destination development pattern are influenced by the tourism attraction and the destination image partially. This research has provided a variety of practical suggestions. Especially, it was suggested that the destination have appeal to tourists by strengthening attraction and improving weakness. Also, we need to specialize destination in same destination development pattern.

• 한국콘텐츠학회논문지
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• 제10권11호
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• pp.435-445
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• 2010

이 연구는 Beard와 Ragheb[9]에 의해 개발되고 국내에서는 이종길[7]이 사용한 여가만족척도의 번안적절성에 그에 따른 타당도를 검증하고 적용성을 검토하기 위해 수행되었다. 연구를 위해 먼저 여가만족척도의 문항과 각 요인의 조작적 정의를 번안 및 역번안을 수행하고 여가학 전문가들이 내용을 검토하였다. 타당도 검증을 위해 설문조사하여 총 515명(대학생 290명, 일반인 225명)의 자료를 분석에 이용하였다. 수집된 자료는 SPSS 14.0과 AMOS 5.0 프로그램을 이용하여 문항분석, 상관분석, 탐색적 요인분석, 신뢰도분석, 다중회귀분석, 그리고 확인적 요인분석을 수행하여 여가만족척도의 신뢰도와 타당도를 검증하였다. 연구결과 기존에 국내에서 사용되던 여가만족척도의 요인의 명칭(심리적, 교육적, 사회적, 신체적, 심미적, 긴장이완)과 문항을 수정하고 조작적 정의를 제시하였다. 또한 자료분석 결과 6개요인, 24개 문항으로 구성된 여가만족척도의 신뢰도와 타당도는 매우 높은 수준으로 나타났다. 또한 여가만족과 삶의 질과의 관계를 분석한 결과 심리적요인과 긴장이완요인에서 유의한 영향을 미치는 것으로 나타났다. 본 연구에서 재 번역되고 타당도가 검증된 여가만족 척도는 향후 국내연구에서 유용한 도구로 사용될 것으로 기대된다.

• 근관절건강학회지
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• 제3권2호
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• pp.177-193
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• 1996

The purpose of this study was to test whether Yoga exercise, one of muscle relaxation, helps to relieve chronic low back paln. Sample were selected from nurses who were worked at K medical center in the period from March 18 to April 23, 1996. The sample size was fifteen. The research design was one-group pretest-posttest design. To test the major research question, this study had the following procedure. The pretest included measuring individuals' degree of pain and discomfort depending on the scope and types of an range of motion, and their pain by their activity of daily living(ADL). The treatment was conducted twice every other week. The reason why this study had twice observations was to control history effect and maturation which treat internal validity in the research design of this study. In this research design, a treatment was to expose Yoga exercise to samples. The exercise was taken in 30 minutes per day for four days in a week (Two consecutive days and twice every other day). The posttest included re-measuring the individuals' the degree of pain and discomfort, and their pain by their ADL. Several hypotheses concerning effect of Yoga exercise was analyzed by the paired t-test, comparing the difference scores between pre and post tests. The results of this study was as follows. The first hypothesis that the post-treatment group taking the Yoga exercise had the pain score lower than the pre-treatment group was supported(t=3.31, p=.005). The second hypothesis that the discomfort score of the post-treatment group had lower than does that of the pre-treatment group was supported(t=2.75, p=.016). The third hypothesis that the post-treatment group had the pain score by ADL lower than does the pre-treatment group was supported(t=5.52, p=.000). In summary, this study examined the effect of a yoga exercise, one of muscle relaxation, on those who were suffered from chronic low back pain. The effect measured by the degree of pain and discomfort with a visual analog scale was statistically significant. The degree of pain according to postures in ADL also showed statistical significance. These findings showed that a yoga exercise was effective to alleviation of chronic low back pain. A pretest-posttest control group design, however, needs to get more accurate results since the design satisfies Internal validity. Consequently, yoga as an exercise cure improves an interaction between muscles and articulations, and performance of ADL for those suffered from chronic low back pain. Furthermore, this positive impact may be an effective method as nursing intervention for their physical, mental, emotional, social, and psychological recovery.

• Journal of Theoretical and Applied Mechanics
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• 제1권1호
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• pp.69-88
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• 1995

The paper attempts to estimate the incubation time of a cavity in the interface between a power law creep particle and an elastic matrix subjected to a uniaxial stress. Since the power law creep particle is time dependent, the stresses in the interface relax. Through previous stress analysis related to the present physical model, the relaxation time is defined by ${\alpha}$2 which satisfies the equation $\Gamma$0 ｜1+${\alpha}$2k｜m=1-${\alpha}$2 [19]. $\Gamma$0=2(1/√3)1+m($\sigma$$\infty$/2${\mu}$)m($\sigma$0/$\sigma$$\infty$tm) where $\sigma$$\infty$ is an applied stress, ${\mu}$ is a shear modulus of a matrix, $\sigma$$\infty$ is a material constant of a power law particle, $\sigma$=$\sigma$0 $\varepsilon$ and t elapsed time. the volume free energy associated with Helmholtz free energy includes strain energies associated with Helmholtz free energy includes strain energies caused by applied stress anddislocations piled up in interface (DPI). The energy due to DPI is found by modifying the results of Dundurs and Mura[20]. The volume free energies caused by both applied stress and DPI are a function of the cavity size(${\gamma}$) and elapsed time(t) and arise from stress relaxation in the interface. Critical radius ${\gamma}$ and incubation time t to maximize Helmholtz free energy is found in present analysis. Also, kinetics of cavity fourmation are investigated using the results obtained by Riede[16]. The incubation time is defied in the analysis as the time required to satisfy both the thermodynamic and kinetic conditions. Through the analysis it is found that [1] strain energy caused by the applied stress does not contribute significantly to the thermodynamic and kinetic conditions of a cavity formation, 2) in order to satisfy both thermodynamic and kinetic conditions, critical radius ${\gamma}$ decreases or holds constant with increase of time until the kinetic condition(eq.40) is satisfied. Therefore the cavity may not grow right after it is formed, as postulated by Harris[11], and Ishida and Mclean[12], 3) the effects of strain rate exponent (m), material constant $\sigma$0, volume fraction of the particle to matrix(f) and particle size on the incubation time are estimated using material constants of the copper as matrix.

• 한국체육학회지인문사회과학편
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• 제55권3호
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• pp.543-551
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• 2016

본 연구는 스마트 폰을 사용(≥ 60분/일)하는 건강한 20대 남성 50명을 대상으로 두부의 움직임에 직접 관여하는 경추부 근육(두판상근, 흉쇄유돌근, 상부승모근)에 연부조직 측정기 Myoton을 이용하여 스마트 폰 사용정도와 경추부 근육의 기계적 속성의 관련성을 규명하려는 목적으로 수행되었다. 스마트 폰 사용정도는 전용의 중독 척도설문지를 이용하였다. 경추부 근육의 기계적 속성은 Myoton을 이용하여 근 긴장도(frequency), 동강성(stiffness), 점탄성(decrement), 근변형률(creep) 및 회복시간(relaxation)의 반영지표를 각각 산출하였다. 스마트 폰 사용에 의한 중독 점수와 경추부 근육의 기계적 속성을 반영하는 각 지표와의 관련성을 평가하기 위해 상관분석을 실시하였다. 연구 결과 기계적 속성을 반영한 모든 parameters의 변동계수는 각각 2% 미만이었으며, 측정자 신뢰도인 급내상관계수 역시 높은 신뢰성이 도출되었다(ICC>.9, p<.01). 스마트 폰 중독점수는 상부승모근의 근 긴장도(r=.353, p<.05)와 동강성(r=.346, p<.05), 흉쇄유돌근의 점탄성(r=-.284, p<.05)과 근 변형률(r=.288, p<.05)과의 유의미한 상관이 나타났고, 특히 두부 통증과 관련된 두판상근의 근 긴장도(r=-.368, p<.01), 점탄성(r=-.405, p<.01), 동강성(r=-.424, p<.01)과의 높은 상관계수로 스마트 폰 과사용과 밀접한 관련성을 나타내었다. 결론적으로 젊은 남성들에 있어서 스마트 폰 과사용은 경추부 근 손상과 통증 및 두통에 유의미한 관련성이 있음을 간접적으로 시사하며, Myoton은 경추부 근육 성질을 예측 및 평가할 수 있는 유용한 기기임을 알 수 있었다.

• 한국심리학회지 : 문화 및 사회문제
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• 제15권3호
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• pp.359-375
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• 2009

본 연구의 목적은 한국형 마음 챙김 명상에 기반한 스트레스 감소 프로그램이 근로자의 만성통증완화에 미치는 영향을 연구 하는데 있다. 이러한 목적을 달성하기 위하여 만성통증을 가진 근로자 20명을 대상으로 프로그램의 효과를 알아보기 위해 사전 검사, 사후 검사, 추수 검사에서 측정한 평균점수로 혼합변량분석(Mixed ANOVA)을 실시하였다. 분석된 자료는 심리적, 신체적, 신경 생리적 반응이었다. 아울러 프로그램 후 각 효과가 지속적으로 유지될 것인가를 추가 검증하고자 3개월 후에 사후검증도 실시하였다. 본 연구 결과, 프로그램 참여 집단의 신체적 증상과 신체화, 강박증, 대인예민성, 우울, 불안, 적대감, 공포불안, 정신증 등의 반응이 프로그램 참여 전에 비해 유의미하게 감소하였고, 또한 생리 및 신경생리지표 또한 프로그램 전에 비해 유의미한 변화가 나타났으며, 3개월 후까지 이러한 변화의 효과가 유지되었다. 본 연구의 결과로 보아 마음 챙김 명상에 기반한 스트레스 감소 프로그램은 통증환자의 심리적, 신체적, 신경생리적 통증완화에 유의미한 영향력을 미치는 것으로 밝혀졌다. 따라서 본 연구결과를 통해 만성통증환자의 임상적 프로그램 개발의 기초자료를 제공하고자 한다.

• The Journal of Korean Physical Therapy
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• 제18권6호
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• pp.1-11
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• 2006

연구목적: 이 연구는 피부표면 냉각이 생체내의 건구조 점탄성 특성에 미치는 영향을 비교하였다. 방법: 7명의 남성 실험 대상자는 족저굴곡 운동을 10회$\times$10set, 60초 간격으로 최대 수의적 수축을 6초간 각각 실시하였다. 각 측정 전후에 내측 비복근(MG)의 건과 건막의 신장은 초음파 검사법에 의하여 직접 측정되었다(건 장력과 건 신장의 관계로 평가 되었다). 건 횡단면적과 족 관절 모멘트 암은 자기공명영상법(MRI)으로부터 얻어졌다. 건 장력은 관절 모멘트와 건 모멘트 암으로 계산되었다. 또한 스트레스는 횡단면적영역(CSA)을 힘으로 나눔으로써 얻어졌다. 스트레인은 건의 길이로 표준화된 치환으로부터 측정되었다. 결과: 냉각 후에 건 장력은, 비냉각 보다 냉각한 측이 유의하게 높았다. 스티프네스는 비냉각 조건 보다 냉각 조건하에서 높은 유의수준을 나타냈다. 최대의 스트레인과 스트레스는 냉각조건하에서 $7.4{\pm}0.7$와 $36.4{\pm}1.8$ MPa을 나타냈고, 비냉각 조건하가 $7.8{\pm}8.5$ 와 $31.8{\pm}1.1$ MPa (p<0.05)을 나타냈다. 결론: 이 연구의 결과는 피부표면 냉각으로 인해 인간의 근지구력이 건 스티프네스와 탄성률을 증가시키는 것을 시사하는 연구라 하겠다. 피부 표면 냉각으로 인한 근지구력의 개선이 근과 건에 직접적인 영향을 미침을 나타내주고 있다.