• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.46-49
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• 1998

In this paper, we introduce the notion of intelligent communication by introducing a novel intelligent receiver model. This receiver is continually evolving and learns and improves in performance as it compiles its experience over time. In digital communication context, in a typical training mode, it jearns the concept of "1" as is deteriorated by arbitrary (not necessarily additive as is typically assumed) disturbance and /or modulation. After learning "1", in test mode, it classifies the received signal "1" and "0" almost completely. The intelligent receiver as implemented is grounded on the recently introduced Stochastic Morphological Sampling Theorem(SMST), a distribution-free result which gives theoretical bounds on the sample complexity(training size) needed for the required performance parameters such as accuracy($\varepsilon$) and confidence($\delta$). Based on this theorem, we demonstrate --almost irrespective of channel and modulation model-- the number of samples needed to learn the concept of "1" is not too "large" and the resulting universal receiver structure, that corresponding to classical Nearest Neighbor rule in Pattern Recognition Theory, is trivial. We check the surprising efficiency and validity of this model through some simple simulations. and validity of this model through some simple simulations.

• 대한간호학회지
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• 제36권5호
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• pp.761-769
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• 2006

Purpose: Even though a number of studies have suggested that appropriate measuring instruments of family stress for working women have to be developed, the validity and reliability of the instruments used have not been consistently examined. The purpose of the present study was to develop a sensitive instrument to measure family stress for married working women, and to test the validity and reliability of the instrument. Method: The items generated for this instrument were drawn from a comprehensive literature review Twenty four items were developed through evaluation by 10 experts and twenty one items were finally confirmed through item analysis. Psychometric testing was preformed and confirmed with a convenient sample of 240 women employed in the industrial sector. Result: Four factors evolved by factor analysis, which explained 50.5% of the total variance. The first factor 'Cooperation' explained 28.1%, 2nd factor 'Satisfaction with relationships' 10.6%, 3rd factor 'Democratic and comfortable environment' 6.3%, and 4th factor 'Disturbance of own living' 5.5%, Cronbach's coefficient of this instrument was 0.86. Conclusion: The study supports the validity and reliability of the instrument.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.229-236
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• 2009

A habitat model was developed to delineate potential habitat of the leopard cat (Prionailurus bengalensis) in a mountainous region of Kangwon Province, Korea. Between 1997 and 2005, 224 leopard cat presence sites were recorded in the province in the Nationwide Survey on Natural Environments. Fifty percent of the sites were used to develop a habitat model, and the remaining sites were used to test the model. Fourteen environmental variables related to topographic features, water resources, vegetation and human disturbance were quantified for 112 of the leopard cat presence sites and an equal number of randomly selected sites. Statistical analyses (e.g., t-tests, and Pearson correlation analysis) showed that elevation, ridges, plains, % water cover, distance to water source, vegetated area, deciduous forest, coniferous forest, and distance to paved road differed significantly (P < 0.01) between presence and random sites. Stepwise logistic regression was used to develop a habitat model. Landform type (e.g., ridges vs. plains) is the major topographic factor affecting leopard cat presence. The species also appears to prefer deciduous forests and areas far from paved roads. The habitat map derived from the model correctly classified 93.75% of data from an independent sample of leopard cat presence sites, and the map at a regional scale showed that the cat's habitats are highly fragmented. Protection and restoration of connectivity of critical habitats should be implemented to preserve the leopard cat in mountainous regions of Korea.

• 설비공학논문집
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• 제2권3호
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• pp.243-255
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• 1990

The objective of this study is to present an efficient measurement method of the effective thermal diffusivity for the fibrous insulation material. The non-linear parameter estimation (NPE) method is adapted for this analysis because of its accuracy and its results are compared with those by other direct methods such as CTP, CHP and STD method. A experimental system is constructed with bell-jar vaccum chamber, diffusion pump, tube type furnace, control unit and data acquisition system included with A/D converter and IBM XT/AT personal computer. The typical results obtained from this study are as follows; 1) NPE method can be recommended as an useful and accurate method to measure the effective thermal diffusivity of insuation material because it is shown that the measurement error compared with those by other direct methods is reduced for standard material, NBS-1450b. 2) NPE method can minimize the effects of ill-measured temperature due to external disturbance, because the final value is found by point to point estimating. 3) NPE method dose not depend on the kinds of heat flux, since the surfac temperature are used to estimate the thermal diffusivity. 4) With NPE method, compared with the steady state method, a measuring time and a sample size could be reduced.

• The Journal of the Acoustical Society of Korea
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• 제22권4E호
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• pp.167-175
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• 2003

Shear wave velocity was measured and grain size analysis was conducted on two core samples obtained in unconsolidated marine sediments of the western continental margin, the East Sea. A pulse transmission technique based on the Hamilton frame was used to measure shear wave velocity. Duomorph ceramic bender transducer-receiver elements were used to generate and detect shear waves in sediment samples. Time delay was calculated by changing the sample length from the transducer-receiver element. Time delay is 43.18 μs and shear wave velocity (22.49 m/s) is calculated from the slope of regression line. Shear wave velocities of station 1 and 2 range from 8.9 to 19.0 m/s and from 8.8 to 22 mis, respectively. Shear wave velocities with depth in both cores are qualitatively in agreement with the compared model〔1〕, although the absolute value is different. The sediment type of two core samples is mud (mean grain size, 8-9Φ). Shear wave velocity generally increases with sediment depth, which is suggesting normally consolidated sediments. The complicated variation of velocity anisotropy with depth at station 2 is probably responsible for sediment disturbance by possible gas effect.

• 한국산림과학회지
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• 제95권6호
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• pp.778-783
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• 2006

표고버섯의 재배와 출하 결정에서 단기 가격의 예측은 매우 중요하다. 표고버섯 가격의 형성에는 많은 요인들이 작용하고 있기 때문에 이를 구조모형으로 예측하는 것은 어려운 일이다. Box-Jenkins 방법을 이용한 표고버섯과 모형선정 과정에서 발생할 수 있는 오류를 줄이고 경우에 따라서는 더 높은 예측력을 가지기도 한다. 이 연구는 1992~2005년의 가락시장 표고버섯 중품 가격자료를 이용하여 시계열 분석 모형을 구축하고 단기 가격을 예측한 것이다. 그리고 분석에 포함되지 않은 2006년의 실제가격과 예측결과를 비교하였다. 분석 결과는 날씨 변화의 영향으로 시장에 교란이 발생하였던 시기를 제외하면 비교적 높은 정확도를 보여 주어 모형의 유용성을 시사한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.82-84
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• 1998

The normal zone propagation velocity and minimum quench energy (MQE) of cable-in-conduit conductors (CICC) has been investigated at the different background magnetic fields and supercritical helium pressures. The sample CICC of 2 m in length was fabricated with triplet NbTi/Cu strands inserting into a round stainless-steel tube. The heat pulse disturbance with duration time about 400 ms was acted on the center region of the CICC to quench the strands. The normal zone propagation velocity increased with operating current of the CICC. The measured velocity with respect to operation current could be fitted with numerical results.

• 대한간호학회지
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• 제33권4호
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• pp.457-463
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• 2003

Purpose. This cross-sectional survey was conducted to describe the sexuality of Korean women after menopause using a national sample, and to examine relationships between the sexuality and demographic, body mass index, and life style factors including smoking, alcohol use, and physical activity. Method. From Dec. 20, 1998 to April 30, 1999, 2196 naturally postmenopausal women aged between 41 and 65 years were recruited by a disproportional stratified random sampling method from 7 metropolitans and 6 provinces in Korea. The questionnaire was used to obtain information on the demographic characteristics, life style factors, body mass index, and sexual activities. Result. The findings show that the frequency of intercourse after menopause decreased among most of postmenopausal Korean women (64.5%). The frequency of women reported their sexual activity as satisfactory was higher among women doing physical activity, not smoking, with higher educational status, with middle socioeconomic status, without sleep disturbance, with lower body mass index, and with good subjective health status. Conclusion. Further studies need to be designed as the longitudinal studies with larger random samples and better measures of sexuality.

• 근관절건강학회지
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• 제18권1호
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• pp.28-38
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• 2011

Purpose: This paper was aimed to investigate the effect of laugher therapy on the pain, depression and sleep disturbance in elderly patients who admitted in long term care facility. Method: This study used a nonequivalent control group pretest-posttest design. A sample of 40 elderly patients (20: experimental group, 20: control group, 65 or older) were recruited. Visual analogue scale was used to measure level of pain level, Geriatric Depression Scale Short Form Korea Version (GDSSF-K) for depression. Sleep Scale for sleep. The laugher therapy was given twice a week for four weeks (8 times). Each therapy consists of preparatory, action and finishing stage. Data were analyzed by PASW 18.0. Results: The pain score in experimental group was significantly different from that in control group (t=4.17, p<.001). The level of depression in experimental group was significantly different from that in control group (Z=4.12, p<.000). The level of sleep in experimental group was not significantly different from that in control group (Z=-1.43, p<.152). Conclusion: A laugher therapy is expected to be practical used an efficient method of a nursing intervention to elderly patients in long term care facility.

• 대한전기학회논문지:전력기술부문A
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• 제48권5호
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• pp.494-501
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• 1999

In this research, ANN modeling method of SMES unit is developed for stability analysis, and the optimal site is selected to maximize stabilization effect of SMES unit. The ANN is trained by learning data which is obtained through the application of complex test function into the traditional mathematical mode. In order to verify the validity of proposed modeling method, fault data of sample power system is applied to both the traditional and the ANN models. When the response of traditional and proposed models are compared, the average error for the active and reactive power are 2.51[%], and 0.24[%], respectively. From the comparison, the relevance of proposed method is validated. For the transient stability analysis, an application method of the proposed model is presented, and the transient stability performance index, which describes system stabilization effect of SMES at disturbance, is also suggested, and optimal site selection method of SMES is presented. In the viewpoint of the voltage stability, system stabilization criterion of local bus is presented from P­V curve, and then optimal site which can maximize the voltage stabilization of the whole power system, is decided from the proposed voltage stability performance index.