• 한국산학기술학회논문지
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• 제15권6호
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• pp.3410-3415
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• 2014

전자 장비에서 발생하는 열은 장비의 성능을 저하시킨다. 이러한 장비의 열을 외부로 방출하기 위한 방법으로 히트싱크가 사용된다. 본 연구에서는 내부터널의 형상을 가지는 히트싱크에 대한 냉각 및 히팅성능을 강제대류 상태에서 열전달 특성에 대하여 고찰하였다. 또한, 시간에 따른 히트싱크의 열전달 특성 및 온도분포의 변화에 따른 실험을 수행하였다. 냉각실험에서 전압이 10V일 때, A형상이 B형상 보다 온도가 낮게 나타났고, 가장 좋은 냉각효과를 나타내었다. 히팅실험에서 전압이 13V일 때, 온도가 A형상이 B형상 보다 높게 나타났고, A형상이 효율이 더 좋은 것으로 판단된다.

• 한국조경학회지
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• 제30권2호
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• pp.1-11
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• 2002

The purpose of this study is to investigate landscape image and define elements of difference in visual preference of bridges on the Han River. To do this end, video was used as a media for the evaluation of the landscape image of 16 bridges on the Han River using a Semantic Differential scale. Data is collected by 50 students from Woosuk University, majoring landscape architecture. Final analysis utilized a total of 704 samples of data. Data is analyzed through descriptive statistics, and spatial image is analyzed by factor analysis algorithm Principle component analysis using Varimax method is applied far extraction and factor rotation. T-test is used to find the difference between the bridge type of preference with the data of factor score. Logistic regression is used to select the factors that influences the visual preference among the image factors. The results of this study can be summarized as follows; The image of whole bridges on the Han River is somewhat orderly, sequential and open. The degree of visual preference of unique bridge type is higher than normal but there are some differences in visual preference within the same type of structure. This suggests that the surrounding landscape is one of the important factor for visual preference. Factors covering the image of bridge are found to be 'aesthetic',　'structure','spatial factor', and 'shape'. Total variance is obtained as 60.4%. The aesthetic variables are the most important factor for visual preference and the structural factor presents no significant difference in visual preference between more preferred and less preferred bridges. Since the collapse of Songsu Bridge, we thought the structural factor is very important but the results of this study suggest that it is more important to consider the aesthetic and spatial factors of the bridge to increase the visual preference when planning and designing bridges. Simulations with more detailed data about surroundings should be utilized practical design.

• 한국조경학회지
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• 제18권4호
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• pp.101-115
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• 1991

A study on the method of evaluation the urban amenity structure in Pusan city was established. Finally a survey sites out of 41 regions were selected on the basis of questionnaires : Taejong-dae and Haeun-dae as a seascape, Pumosa and Daesin-park as a mountain, Daechong-park and Seongjigok-park as a mixed, and Chungryulsa, Yongdoosan-park and U. N. Cemetry as a urban type. The abstracted results of amenity elements were revealed as natural environments including convex type as beach, reservoir, valley and mountain, and plant elements including woods and flower beds which raised amenity. The elements of social surroundings including children's playing, the aged's rest, and elements of structures including historic and memorial structures and high buildings. Amenity element made up of each space by region were abstracted from the Semantic Differential method. According to the factor analysis on the ground SD scale values, Kaiser's measure of sampling adequacy for 24 variables is 08602 and very high. Four factors including pleasantness, healthiness, convenience and safety showed 54.42 percent for total variance. By means of multiple regression, the model was as follows : Y=1.6636+0.3684X4+0.1955X11+0.1614X15-0.1688X23+0.1468X24. Therefore, Y:amenity, X4:beautiful-ugly, X11:clean-dirty, X15:creative-imitative, X23:cozy-dreary, X24:free-restrained. All variables in the model were significant at 0.001 level. According to the results of regression on satisfaction, the variables of satisfaction affecting amenity are the size of green space, the condition of management and the harmony with the surroundings. I think the considerating on the above could improve amenity of each region and further Pusan city.

• 응용통계연구
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• 제13권2호
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• pp.393-405
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• 2000

원래 최적실험의 이론은 주어진 모형과 그에 따른 가정에 기초하여 발달되었기 때문에 하나의 최적실험기준이 실험이 가족 있는 여러 목적을 모두 반영하는 것이 무리이다. 따라서 실험자가 다목적 실험기준의 필요성을 느끼는 경우에는 종종 여러 최적실험 기준들의 균형을 이루는 방법을 통해 이러한 문제가 다루어진다. 본 연구에서는 이 분산 구조를 가지고 있는 모형을 예를 들어 복합적인 실험기준들을 알아본다. 왜냐하면 이분산인 경우 D-최적과 G-최적실험간의 동격이론은 더 이상 성립되지 않음에 따라 두 실험기준의 특징은 현격하게 구분되어지기 때문이다. 제약조건최적실험, 결합최적실험, 그리고 minimax 설험방법을 통한 실험기준들간의 균형을 꾀하여 보았다. 처음 두 방법은 실험자의 주관이 반영되어 실제적으로 매우 세심한 주의가 필요한 반면, minimax는 그러한 점을 해소하였다고 본다. 또한 이를 확장하여 오차의 이분산 구조에 대한 불확실성이 존재할 때 적용될수 있는 두 가지 실험기준도 마련하여 보았다. 간단한 알고리즘과 결어를 첨부하였다.

• 대한치과기공학회지
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• 제39권2호
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• pp.101-107
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• 2017

Purpose: The purpose of this study was to compare the shear bond strength of the metal-heat pressed glass ceramic bilayer structure. Methods: Metal framework specimens were prepared and surface is spreaded opaque(IPS InLine system opaque, IvoclarVivadent, Liechtenstein). There were 10 specimens for each bilayer dental ceramic group. The first group was porcelain fused metal, Press on metal IPS Inline press group, and press on metal HASS prototype group. Specimens measured for the shear bond strength on Schwickerath test by Instron universal testing machine(Instron3345, Instron Corp., USA). Mean average bond strength values of each specimen group were analyzed using a one-way ANOVA analysis of variance Saphiro-wilk's test. Statistical analysis were performed using IBM SPSS 23.0(IBM Co., Armonk, USA) Results: $RMS{\pm}SD$ The highest mean average HASS POM showed a bond strength value ($47.55{\pm}12.80Mpa$). The lowest mean average values Porcelain fused metal ($33.30{\pm}2.00Mpa$). Independent t-test was conduct to analysis the significant difference (p<0.05) (Table 3). Conclusion: Three kinds of Metal/ glass bilayer dental ceramics bond strength were clinical acceptability. Especially, as lithium disilicate containing represents higher bond strength.

• 가정과삶의질연구
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• 제7권2호
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• pp.199-212
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• 1989

The main purpose of this paper is to investigate the factors which affect the alienation of the aged, and to study the relative importance of these factors. This study focused on the following research questions: 1) How do the demographic variables(sex, marital status, family structure, religion, economics, prior occupation, education level) affect the alienation of the aged? 2) How the alienation of the aged is affected by their involvement in social activities? 3) Does the degree of satisfaction with family relationship have a perceivable impact on the alienation of the aged? 4) How does the self-rated senescence affect the alienation of the aged? The research was practiced from the 18th Sept. 1999 to the 30th Sept. 1988, through individual interviews with 300 elderly people, all living in Seoul area. Among them only 285 were used in the analysis. The major findings of the study are as follows; 1) The sex of the respondents makes no difference in the alienation of the age . 2) Marital status is found to be relatively significant in determining the alienation. The degree of alienation of old people with spouse is substantially lower than that of those without spouse. 3) Family structure was found to have no significantly effect on the alienation of the aged. 4) Involvement in religion was found to significantly reduce the alienation of the aged. 5) Econimic factors seems to be critical in defermining the aged. The amount of pocket money avaliable for daily use has direct relationship with alienation. 6) Prior occupation was found to be another significant factor affecting alienation professionals experience far lower alienation than nonprofessionals. 7) The higher is education level, the lower is the alienation of the aged. 8) Active participation in social activities and good relationship with other family members were founded to contribute to lowering the alienation of the aged. Whereas, too much concern over one's senescence appears to hav negative effects on the alienation. The regression analysis shows that the satisfaction with the family relationship has the most important influence upon the alienation of the aged. Following are the factors of self-rated senescence, pocket money in a descending order. All these factors, which explain 42.65% of the total variance of alienation variable are statistically significant(p<.001)

• 한국보건간호학회지
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• 제12권2호
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• pp.107-121
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• 1998

The purpose of this study was to test the revised Health Promotion Model of Pender and to determine the factors to promote health behavior for adolescents' smoking behavior. The subjects of the study was 783 boys of 4 high school students. among 39. schools locating in Daejeon metropolitan city. The data was collected from July 1st to 15th. 1997 by school health nurse The research tool were HPLP of Walker. Pender. General self-efficacy scale of Sherer. control scale was measured by subconcept of hardiness scale of Pollock. and perceived barrier. perceived benefit. activity-related-affect tool were made by researcher via literature review The data were analyzed by SAS program using frequency. t-test. ANOVA. Schefee test. regression. The results were as follows 1. The mean of total health promoting behavior was $2.27\pm.35$. Among sub domain of health promoting behavior, the highest score was interpersonal support$(2.72\pm.60)$. and the lowest was health responsibility $(1.58\pm.44)$. 2. There were statistically significant difference in total health promoting behavior according to religion. parenting style. school performance. girl friend. father's smoking of individual characteristics. 3. The socioeconomic status. smoking, parent pattern. family structure of individual characteristics and experience domain associated with perceived benefit. perceived barrier. activity-related affect. interpersonal influence of behavior-specific cognition and affect domain. The perceived barrier. self-efficacy. girl friend and father's smoking of interpersonal influence. and control explained $25.8\%$ of variance of health promoting behavior. From above results school health nurse has to emphasize on health responsibility for health promotion of adolescent. But they couldn't intervene for parent pattern. socioeconomic status. family structure of individual characteristics and experience domain. it could be possible for school health nurse to promote health of adolescents through improving perceived barrier. also develop program to increase self-efficacy and through parent health class for fathers. Above results point to the importance of including parents in smoking prevention effort targeting adolescents. Because increasing control also promotes health of adolescents. it should be studied further about the specific measure. To verify the variables for increasing the fitness of health promoting model. it needs further replication of the research.

• 생물정신의학
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• 제20권1호
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• pp.21-27
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• 2013

Objectives There is a controversy regarding the construct validity of anxiety and depression. Some believe that these two symptoms are basically the same construct, that is, both measure what is called 'general distress' or two phenomena are distinct experiences which often coexist. To further understand relationship between anxiety and depressive symptoms, we investigated the factor structure of a combined anxiety and depression scale among psychiatric outpatients. Methods Data of Zung's Self-Rating Depression and Anxiety Scales were gathered from 401 newly visiting psychiatric outpatients at a university-affiliated hospital. We performed a component analysis on the 40 items from two scales. Results Exploratory factor analysis revealed a seven factor structure explaining 56% of total variance. Overall finding indicated that depression and anxiety scales consisted of four symptom domains : mainly depressive symptoms, mainly anxiety symptoms, common somatic symptoms, and others. Conclusions Our results suggest that the construct of self-reported depressive and anxiety symptoms are more complex than previously thought, i.e., either one or two factor theories. These findings also support that anxiety and depression can be better modeled by dimensional approach. Clinicians may be alert for the fact that both depression and anxiety scales measure distinct and also common aspects. Further researches on other scales especially, interview based instruments are needed.

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.279-290
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• 2012

Plecoglossus altivelis (ayu) is an amphidromous fish widely distributed in Northeastern Asia from the East China Sea to the northern Japanese coastal waters, encompassing the Korean Peninsula within its range. The shore lines of northeastern region in Asia have severely fluctuated following glaciations in the Quaternary. In the present study, we investigate the population genetic structure and historical demographic change of P. altivelis at a population level in East Asia. Analysis of molecular variance (AMOVA) based on 244 mitochondrial control region DNA sequences clearly showed that as the sampling scope extended to a larger geographic area, genetic differentiation began to become significant, particularly among Northeastern populations. A series of hierarchical AMOVA could detect the genetic relationship of three closely located islands between Korea and Japan that might have been tightly connected by the regional Tsushima current. Neutrality and mismatch distribution analyses revealed a strong signature of a recent population expansion of P. altivelis in East Asia, estimated at 126 to 391 thousand years ago during the late Pleistocene. Therefore it suggests that the present population of P. altivelis traces back to its approximate demographic change long before the last glacial maximum. This contrasts our a priori expectation that the most recent glacial event might have the most crucial effect on the present day demography of marine organisms through bottleneck and subsequent increase of effective population size in this region.

• Journal of Microbiology and Biotechnology
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• 제23권6호
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• pp.739-749
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• 2013

The seasonal and spatial diversity of picocyanobacteria (Pcy) in lakes of the Great Mazurian Lakes (GLM) system was examined by DGGE analysis of molecular markers derived from the 16S-23S internal transcribed spacer (ITS) of the ribosomal operon and the phycocyanin operon (cpcBA-IGS). The study of nine lakes, ranging from mesotrophy to hypereutrophy, demonstrated seasonal variance of Pcy. The richness and Shannon diversity index calculated on the basis of both markers were higher in spring and lower in early and late summer. No statistically significant relationships were found between the markers and trophic status of the studied lakes or Pcy abundance. There were, however, statistically significant relationships between the diversity indices and sampling time. The analysis pointed to a different distribution of the two markers. The ITS marker exhibited more unique sequences in time and space, whereas a greater role for common and ubiquitous sequences was indicated by the cpcBA-IGS data. Examination of the Pcy community structure demonstrated that communities were grouped in highly similar clusters according to sampling season/time rather than to the trophic status of the lake. Our results suggest that time is more important than trophic status in shaping the diversity and structure of Pcy communities. The seasonal changes in picocyanobacteria and differences in diversity and community structures are discussed in the context of well-established ecological hypotheses: the PEG model, intermediate disturbance hypothesis (IDH), and horizontal gene transfer (HGT).