• Title/Summary/Keyword: Two-point correlation

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Air Quality Evaluation with Passive Samplers for Large Cities (Passive Sampler를 이용한 대도시의 대기질 평가)

  • Jeon, Eui-Chan;Kim, Shin-Do;Choi, Kum-Chan
    • Journal of Environmental Impact Assessment
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    • v.7 no.2
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    • pp.83-88
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    • 1998
  • Filter badge type sampler has not been widely used to evaluate air quality over large cities in Korea while it can be successfully used for multi-point sampling and analysis. We evaluated the passive sampler as a new tool to monitor air quality over large cities. We latticed Metropolitan Seoul into $2{\times}2Km$ to give 136 points. $NO_2$ concentrations were measured at all the points in the Spring and Summer of 1997. According to the passive sampler data, natural green zones generally recorded lower $NO_2$ concentrations than major streets and traffic congestion areas. Passive samplers with abundant 136 points gave more detailed picture of $NO_2$ distribution while auto-monitoring network did not clearly provide the characteristics of local land use. Also, passive samplers gave 15% higher values than auto-monitoring network. The correlation between the two values appears very high judging from the regression slope of 0.92 and correlation coefficient of 0.91. This study clearly demonstrates the effectiveness of the passive sampler as a tool to monitor air quality over large cities.

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Validation Study of the Practice Environment Scale of Nursing Work Index for Psychiatric Hospital Nurses in Korea (한국 정신간호영역에서의 간호업무환경 측정도구의 타당화 연구)

  • Kim, Hee Jung
    • Journal of muscle and joint health
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    • v.21 no.3
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    • pp.224-235
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    • 2014
  • Purpose: The purpose of this study was to test the reliability and the validity of the Practice Environment Scale of Nursing Work Index (PES-NWI) scale when applied to Korean psychiatric nurses working in the psychiatric hospital in Korea. Methods: Data from 224 psychiatric nurses working in the 6 psychiatric hospitals in Korea were analyzed using Cronbach's ${\alpha}$, item total correlation, and exploratory factor analysis. Results: The Cronbach's ${\alpha}$ for the 27 items from the PES-NWI were .93, and the item total correlation coefficients ranged from .38 to .64. Six factors which explained 61.2 of variance in the perception of practice environment, emerged; nurse professional role and development, nurse manager ability, leadership, and support of nurses, staffing and resource adequacy, nursing foundation for quality of care, collegial nurse-physician relations, co-worker's ability and qualification. Five derived factors reconstructed, and two factors were renamed. Conclusion: Findings demonstrate that not all but 27 items from PES-NWI is a reliable and valid scale when applied to Korean psychiatric nurses working in Korea. Also findings indicate that Korean psychiatric nurses perceive practice environment differently than American nurses but have some point of similarities with Asian nurses working in the United States.

The clustering of critical points in the evolving cosmic web

  • Shim, Junsup;Codis, Sandrine;Pichon, Christophe;Pogosyan, Dmitri;Cadiou, Corentin
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.47.2-47.2
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    • 2021
  • Focusing on both small separations and baryonic acoustic oscillation scales, the cosmic evolution of the clustering properties of peak, void, wall, and filament-type critical points is measured using two-point correlation functions in ΛCDM dark matter simulations as a function of their relative rarity. A qualitative comparison to the corresponding theory for Gaussian random fields allows us to understand the following observed features: (i) the appearance of an exclusion zone at small separation, whose size depends both on rarity and signature (i.e. the number of negative eigenvalues) of the critical points involved; (ii) the amplification of the baryonic acoustic oscillation bump with rarity and its reversal for cross-correlations involving negatively biased critical points; (iii) the orientation-dependent small-separation divergence of the cross-correlations of peaks and filaments (respectively voids and walls) that reflects the relative loci of such points in the filament's (respectively wall's) eigenframe. The (cross-) correlations involving the most non-linear critical points (peaks, voids) display significant variation with redshift, while those involving less non-linear critical points seem mostly insensitive to redshift evolution, which should prove advantageous to model. The ratios of distances to the maxima of the peak-to-wall and peak-to-void over that of the peak-to-filament cross-correlation are ~2-√~2 and ~3-√~3WJ, respectively, which could be interpreted as the cosmic crystal being on average close to a cubic lattice. The insensitivity to redshift evolution suggests that the absolute and relative clustering of critical points could become a topologically robust alternative to standard clustering techniques when analysing upcoming surveys such as Euclid or Large Synoptic Survey Telescope (LSST).

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Study on the Physical Properties according to the Anisotropy of Granite (화강암의 이방성에 따른 물리적 특성 연구)

  • 박윤석;강추원
    • Explosives and Blasting
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    • v.21 no.4
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    • pp.23-35
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    • 2003
  • This study is to clarify the comparative relationship and a mechanical anisotropy of rock on the subject of granite distributed in the Namwon area Uniaxial compressive and Brazilian strengths with respect to the horizontal and vertical axes of granite are shown the linear relation. In the case of the result of the p-wave velocity measurement. it is represented that the velocity of vortical direction is faster about 10 to 15% than other two horizontal directions. The difference between velocities is caused by a developmental pattern of microcracks distributed in rock. Moreover, this result is very consistent with the result investigated through thin sections. The proportion of uniaxial compression strength to Index of point load strength ($Is_{(50)}$) is 18~20 times in case of granite. Uniaxial compressive strength is relatively good relationship with point load strength, Schmidt hammer rebound value, and tensile strength point load strength of them is the best comparative relationship. It is indicated that point load test is the most useful tool to estimate uniaxial compressive strength, comparing with other experimental methods.

Evaluation on validity of health literacy measurement scale (의료정보이해능력 측정도구 척도의 타당성 평가)

  • Choi, Kyounh-Ho;Lee, Jeong-Ok
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.2
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    • pp.257-265
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    • 2013
  • As evaluating the health literacy is getting important, various measures for evaluation are being developed. Nevertheless, discussions about developing proper measures in Korean are still inactive. Therefore in this paper, we proposed Korean REALM (rapid estimate of adult literacy in medicine) measure that is composed of five point scale and investigated about its validity. As a result, we could find that Korean REALM measure which is composed of five point scale has high reliability, and that it formed one dimension as a result of factor analysis. Positive responses were lower than two point scale and correlation coefficient with NVS (the newest vital sign) appeared statistically significant. Therefore, we could conclude that Korean REALM measure that is composed of five point scale is a valid measurement. Furthermore, there were statistically significant differences between general students and department of nursing students about health literacy.

Vertical Variations Analysis of Air Temperature and CO2 Concentration in the Grassplots (잔디밭에서 기온과 이산화탄소 농도의 연직 변동 분석)

  • So, Yoon Hwan;Kang, Dong Hwan;Kim, Il Kyu;Kim, Byung Woo;Yoon, Hwan Jin;Kim, Si Hyeon;Son, Yong Seok;Shin, Jung Hyeon;Ahn, Jeong Woo
    • Journal of Environmental Science International
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    • v.26 no.2
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    • pp.147-157
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    • 2017
  • This study investigated the characteristics of variations in carbon dioxide concentration and air temperature with the vertical change of surface in a grassplot. Field observations were carried out at a grassplot in Gyeongnam Science High School, over four days in August and November, 2015. Continuous observation equipment (GMP343, VAISALA) was installed at the LP (0.1 m from the surface) and UP (1.1 m from the surface) points, and the carbon dioxide concentration and air temperature were measured simultaneously at 1-min intervals. To summarize the results of the observation, August had higher than average concentrations of carbon dioxide, while November showed average air temperatures. Moreover, the concentration of carbon dioxide was higher at the UP point, while the air temperature was higher at the LP point. The correlation coefficient of carbon dioxide concentration between the UP and LP points was 0.80 in August across all the four days, while it was higher in November at 0.58-0.95. The results of the regression analysis of carbon dioxide concentration with air temperature changes for both August and November showed a distinct change at the LP point (R2=0.36-0.76), as compared to the UP point (R2=0.1-0.57). Between the UP and LP points, the carbon dioxide concentration and air temperature regression analysis results indicated that an active exchange was taking place between the two points.

Application of the High Resolution Aerial Images to Estimate Nonpoint Pollution Loads in the Unit Load Approach (원단위법에 의한 비점오염부하량 산정 시 토지피복 특성을 반영하는 고해상도 항공영상의 활용방안)

  • Lee, Bum-Yeon;Lee, Chang-Hee;Lee, Su-Woong;Ha, Do
    • Journal of Environmental Impact Assessment
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    • v.18 no.5
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    • pp.281-291
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    • 2009
  • In Total Water Pollutant Load Management System of Korea, unit load approach based on land register data is currently used for the estimation of non-point pollutant load. However, a problem raised that land register data could not always reflect the actual land surface coverages which determine runoff characteristics of non-point pollution sources. As a way to overcome this, we tried to establish quantitative relationships between the aerial images (0.4m resolution) which reflect actual land surface coverages and the land registration maps according to the 19 major designated land-use categories in Kyeongan watershed. Analyses showed different relationships according to the land-use categories. Only a few land-use categories including forestry, road and river showed essentially identical and some categories such as orchard, parking lot and sport utility site showed no relationships at all between image data and land register data. Except for the two cases, all the other categories showed statistically significant linear relationships between image data and land register data. The analyses indicate that using high resolution aerial maps is a better way to estimate non-point pollutant load. If the aerial maps are not available, application of the linear relationships as conversion factors of land register data to image data could be an possible option to estimate non-point pollutant loads for the specific land-use categories in Kyeongan watershed.

Analysis of Online Educational Videos for Patients with Radiation Therapy (방사선치료 환자를 위한 온라인 교육 동영상 분석)

  • Kim, Dae-Gun;Jeong, Jae-Hong
    • Journal of radiological science and technology
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    • v.45 no.1
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    • pp.31-39
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    • 2022
  • This study aimed to analyze educational understanding and satisfaction by survey including for the online educational videos by used online platform (YouTube) which provide resolve patient's questions, require attention and treatment information for a patient with radiation therapy. Video viewing analysis was used by YouTube studio. The survey was analyzed general properties (age, academic ability, disease, and watched of no watched videos) and educational understanding and satisfaction for two groups as no watched and watched patients. The views number was 60% at the female higher than 40% at the male. Based on the standard viewing time (hours), the non-subscription rate was 86.7%. The device type mostly used the mobile phone (82.8%). The viewership of educational videos was lower as the age increased and the academic ability decreased in the survey. The educational understanding increased by 22% at watched group as 4.15 point from at no watched group as 3.4 point (p<0.001), and the educational satisfaction increased by 15.8% at watched group as 4.25 point from at no watched group as 3.67 point (p<0.01). The correlation of understanding (r=0.761) and satisfaction (r=0.767) was high for both no watched and watched groups (p<0.01). The online educational videos increased educational understanding and satisfaction for the patient with radiation therapy. Our study could be used references data for improving the quality of medical services.

Cohabitation, Loneliness, and Family Function among University Students (대학생들의 혼전 동거 경험과 외로움 및 가족기능에 관한 연구)

  • Kim, Hae-Ran;Kim, Kye-Ha
    • Korean Journal of Adult Nursing
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    • v.22 no.5
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    • pp.509-518
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    • 2010
  • Purpose: The purpose of this study was to examine the state of unmarried cohabitation and to compare the differences of loneliness and family function among university students with cohabitation experience and those with no experience in Korea. Methods: A convenience sample of 213 university students was recruited from three universities located in G city and the Chonnam area of Korea. Data collection methods included: (a) a demographic questionnaire, (b) a questionnaire related to cohabitation, (c) UCLA scale: 20 items on a 4-point scale (c) Family APGAR questionnaire: 5 items on a 3-point scale. SPSS/WIN 17.0 was used for descriptive analysis, ${\chi}^2$ test, t-test, and Pearson correlation. Results: In this study, 21.1% of the subjects had experiences of unmarried cohabitation. The cohabitation experience was related to gender, age, and monthly income. There was significant differences in family function between the two groups. Loneliness scores were significantly correlated with family function scores in the non-cohabitation group. Conclusion: To improve sex life of the university students, healthcare providers including school nurses may consider family function.

Inverted-U curve for material consumption of China industrial system: a new implication from environmental regulation

  • Fang, Yiping
    • Advances in environmental research
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    • v.1 no.4
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    • pp.237-255
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    • 2012
  • We review the research literature on relationship between environmental regulation and industrial development in three aspects of environmental regulation and investment, environmental regulation and efficiency, environmental regulation and trade. Indeed, the linkage between environmental regulation and material consumption of industrial system is absent. Environmental regulation is measured as the expenditure share for industrial pollutants abatement, and effluent charge intensity. Using panel-level data from 31 provinces, municipalities and autonomous regions in China, we build correlation models between material consumption and environmental regulation, results show that: (1) there are significant quadratic function relationship between material consumption and environmental regulation. And there is the fact that inflection point exists. (2) On basis of inflection points, we make two remarkable reflections. Firstly, the inflection points are the most important scale to judge reasonability and performance of regulations. Secondly, a Pareto improvement may occur when the regulations achieve a certain target. (3) Both intensities of industrial pollutants abatement expenditure and effluent charge have not yet achieved the expected target in most regions of mainland China at present. And most of regions of material consumption decreasing are distributed in western China. Main reasons lie in the impacts of industrial features as well as the regulations.