• 설비공학논문집
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• 제10권5호
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• pp.550-557
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• 1998

The saturated vapor density correlation proposed here relates logarithmic density to the inverse of temperature. Its performance is examined correlating the date listed in the ASHTAE tables for 40 refrigerants. The correlation equation is valid over the entire range where data point exist and gives better results than a conventional equation with the same number of adjustable coefficients. Number of terms in the equation is a variable so that great flexibility can be given to the representation of data.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제10권3호
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• pp.273-281
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• 2004

동영상의 현재 블록의 움직임 벡터와 이전 블록의 움직임 벡터는 시간적 상관성을 갖고 있다. 본 논문에서는 영상의 시간적인 특성과 움직임 벡터의 가운데 중심 분포 특성을 이용하는 예측 탐색 알고리즘을 제안한다. 제안된 알고리즘은 이전 프레임 블록으로부터 예측된 움직임 벡터와 분할된 탐색 구간에 속하는 후보 벡터 중에서 가장 작은 SAD 값을 갖는 점을 정확한 움직임 벡터를 찾기 위한 초기 탐색점 위치로 결정한다. 실험 결과 제안된 방식은 FS를 제외한 기존의 대표적인 고속 탐색 방식들에 비해 PSNR 값에 있어서 평균적으로 0.19∼0.46㏈ 개선되고 영상에 따라 최고 1.06㏈ 정도 우수한 결과를 나타내었다.

• 동력기계공학회지
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• 제19권3호
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• pp.11-15
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• 2015

In this paper, the multi-point hydrogen detection system based on the combination of the hetero-core optical fiber SPR hydrogen tip sensor and interrogator by pseudorandom noise (PN) code correlation reflectometry has been developed. In a light intensity-based experiment with an LED operating at 850 nm, it has been presented that a transmitted loss change of 0.32dB was induced with a response time of 25 s for 4% $H_2$ in $N_2$ in the case of the 25-nm Au, 60-nm $Ta_2O_5$, and 5-nm Pd multi-layers film. The proposed sensor characteristic shows excellent reproducibility in terms of loss level and time response for the in- and out- $H_2$ action. In addition, in the experiment for multi-point hydrogen detection, all sensors show the real-time response for 4% hydrogen adding with reproducible working. As a result, the real-time multi-point hydrogen detection could be realized by means of the combination of interrogating system and hetero-core optical fiber SPR hydrogen tip sensors.

• 디지털산업정보학회논문지
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• 제7권2호
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• pp.115-125
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• 2011

An accurate estimation of software development size is an important factor in calculating reasonable cost of project development and determining its success. In this study, we propose estimation models, using function point based on the functional correlation between software, with empirical data. Three models($FP_{est}(I)$, $FP_{est}(II)$, $FP_{est}(III)$) are developed with correlation and regression analysis. The validity of the models is evaluated by the significance test by comparing values of Mean Magnitude of Relative Error (MMRE) and predictions of each model at level n%. Model $FP_{est}(III)$ proved to be superior to other models such as IFPC(Indicative Function Point Count), EFPC(Estimated Function Point Count), EPFS(Early Prediction of Function Size), $FP_{est}(I)$, and $FP_{est}(II)$. As a result, the accuracy of the model appears to be very high to determine the usefulness of the model to finally overcome weakness of other estimation models. The model can be efficiently used to estimate project development size including software size or manpower allocation.

• 한국의류학회지
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• 제34권6호
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• pp.913-927
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• 2010

This study investigates the influence of Likert scale formats such as the number of response categories and the inclusion of a mid-point from a methodological point of view using instruments that measure a fashionmarketing-related subject. Using a self-administered questionnaire, 201 respondents rated their economic clothing shopping orientation on three formats of scales that differed only in the number of response categories (ranging from 5 to 7) from February 8 to February 12, 2010. Descriptive statistics, Spearman's rank order correlation, t-test, exploratory factor analysis, confirmatory factor analysis, Pearson's correlation, and Cronbach's alpha were used in the analysis. The results are as follows. First, three scale formats were generally suitable for use due to validity and reliability. Second, the response results varied with the number of categories and the inclusion of a mid-point, although the differences were statistically insignificant (with only a few cases that differed). Third, construct validity was more secure in scales with fewer categories, whereas convergent and discriminant validity was generally good in all scale formats. Fourth, reliability coefficients were higher in scales with more categories. Fifth, the number of categories was of greater importance to instrument design than the inclusion of a mid-point. Implications for appropriate scale designs are suggested in this study.

• 종양간호연구
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• 제9권2호
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• pp.129-135
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• 2009

Purpose: This study was to explore the psychosocial adjustment, marital intimacy and family support of post-mastectomy patients. Methods: The subjects were 90 post-mastectomy patients (stage I or II) who were eligible and agreed to participate in the study. The data collection period was from March to May, 2008. Subjects completed a survey including demographics, psychosocial adjustment scale by Lee (a 4-point Likert scale), marital intimacy scale by Kim (a 4-point Likert scale), and family support by Shim (a 5-point Likert scale). Data were analyzed using SAS (ver 9.0) program and frequency, mean (SD), t-test, ANOVA and Pearson correlation coefficients were used. Results: The mean scores of the psychosocial adjustment and marital intimacy were 2.8 (${\pm}0.4$) and 2.5 (${\pm}0.5$). Also, the mean score of the family support was 3.6 (${\pm}0.7$). Regarding the correlation between the psychosocial adjustment, marital intimacy and family support, there was a positive correlation. Conclusion: These results showed that subjects who had higher marital intimacy and family support showed better in psychosocial adjustment. To improve psychosocial adjustment of post-mastectomy patients for breast cancer more effectively, there is an necessity to provide various strategic supports and intervention for effective communication with spouse and family.

• 지질공학
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• 제24권4호
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• pp.463-471
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• 2014

This paper considers the effect of rainfall on non-point source (NPS) pollutant loads. The impact of runoff on the occurrence of NPS pollutants was found to be influenced by rainfall amount, rainfall intensity, and the number of antecedent dry days (ADD), both independently and in combination. The close correlation ($R^2$ = 0.9920) between rainfall and runoff amounts was demonstrated at the study site (a flower farm) over the period between January 2011 and December 2013. The relationships among pollutant levels, runoff, and rainfall was not satisfactory results except for the Biochemical Oxygen Demand ($BOD_5$). The correlation coefficients between $BOD_5$, and both runoff and rainfall, were greater than 0.92. However, the relationships of other pollutants, such as Suspended Solid (SS), Chemical Oxygen Demand ($COD_{Mn}$), Total Nitrogen (TN), and Total Phosphorus (TP), with runoff and rainfall had correlation coefficients of less than 0.70. The roles of rainfall was different from rainfall categories on the occurrence of runoff. Instantaneous rainfall intensity was a principle factor on the occurrence of runoff following light rainfall events (total ${\leq}30mm$). For rainfall of intermediate intensity (total precipitation 31-50 mm), the combined effect of both average rainfall intensity and ADD was found to influence runoff generation. We conclude that the control of NPS pollutants with the reflection of the climate change that makes the remarkable effect of amounts and forms on the rainfall and runoff.

• 한국보건간호학회지
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• 제22권1호
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• pp.97-107
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• 2008

Purpose: To investigate the relationships among self-esteem, depression and academic achievement in nursing college students. Method: The study subjects consisted of 350 nursing college students. The data were collected by self-administered questionnaire from September 3rd to 28th 2007. Results: 1) The mean scores self-esteem, depression, and academic achievement were 3.03 (on a 4-point scale), 4.00 (on a 7-point scale), and 87.33 (on a 100-point scores), respectively. 2) There were significant differences and impacts on self-esteem according to the economic state, character, attitude to parents, consideration of aptitude, satisfaction of school life and satisfaction of nursing. Depression differed significantly according to the economic state, residence type and satisfaction of school life. Academic achievement differed depending on the attitude to parents, consideration of aptitude and satisfaction of nursing. There was a significant positive correlation between self-esteem and academic achievement, but a negative correlation between self-esteem and depression in nursing college students. Conclusion: There was a positive correlation between self-esteem and academic achievement. Moreover, self-esteem can provide a basis for constructing further studies in intervention programs relating to the curriculum for nursing college students. Based on the above findings, programs are needed for the improvement of self-esteem and the reduction of depression, and further research is suggested on the development of such programs.

• 한국생산제조학회지
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• 제23권5호
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• pp.498-504
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• 2014

Displacements and strains are very important for material evaluation as critical factors to a machine's life cycle and safety. Typically, the strain gauge has been employed to measure displacement and strain. However, this contact-type measurement method has disadvantages that are not quantified under the test conditions of a specific object shape, surface roughness, and temperature. In this paper, the measurement of deflection and flexural strain due to the three-point bending test is presented, employing Digital Image Correlation (DIC) methods. In order to ensure measurement reliability, DIC and universal test machine methods were compared by measuring the deflections and flexural strains developed by such bending tests.

• International Journal of Computer Science & Network Security
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• 제22권4호
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• pp.159-168
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• 2022

The recent outbreak of COVID-19 pandemic cases around the globe has affected Saudi Arabia with around 15, 00,000 confirmed cases within the initial 4 months of transmission. The present investigation analyzed the relationship between daily COVID-19 confirmed cases and meteorological parameters in seventeen cities of KSA. We used secondary published data from the Ministry of Health, KSA daily dataset of COVID-19 confirmed case counts. The meteorological parameters used in the present investigation are temperature, humidity, dew point, and wind speed. Pearson correlation and Spearman rank correlation tests were utilized for data analysis. The incubation period of COVID-19 varies from 1 day to 14 days as per available information. Therefore, an attempt has been made to analyze the effects of meteorological factors with bins of 1, 3, 7, and 14 days. The results suggested that the highest number of correlations (15 cities) was observed for temperature (maximum, minimum, and average) and humidity (12 cities) (minimum and average). The dew point showed relationships for 7 cities and wind showed moderate correlations only for 2 cities. The study results might be useful for authorities and stakeholders in taking specific measures to combat the Covid-19 pandemic.