• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.41-49
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• 1997

Status of photochemical air pollution in the Greater Seoul Area (GSA) between 1990 and 1995 was assessed in terms of frequency distributions, number of days exceeding standards, average concentration and meteorological effects. In Seoul compared with other areas in Korea, daily maximum concentration was higher but average concentration was not so high due to lower daily minimum from April to October. The top 5th percentile was high especially in summer season. Average number of days exceeding 100 ppb at monitoring stations in GSA was highest in 1994, the hottest year, but it was only 4 days a year. Mean meteorological pattern of high ozone days could be summarized as low wind speeds, high temperatures, strong solar radiation, and low precipitation. Westerlies were more frequent on high ozone days and at Pangi station located in the eastside of GSA, both number of high ozone days and average concentration were high. Effect of precursor transport on the rise of ozone concentration was, however, not consistently important on the whole in GSA.

• International Journal of Human Ecology
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• v.5 no.2
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• pp.81-91
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• 2004

The purpose of this study is to evaluate consumer use of unit price information introduced in Korea 1999. A total of 571 observations were analyzed by frequency, percent, and paired t-test using SPSS. The main findings are (1) consumers use unit price information to make better purchase decisions, (2) consumers with higher than average attentiveness in purchase behavior utilize unit price information to make better buying decisions, and (3) consumers with higher than average knowledge utilize unit price information to make better buying decisions. (4) Also if either attentiveness in purchase behavior or consumer knowledge is lower than average, unit price information helped consumers make better purchase decisions. (5) However, there was no difference among those consumers with below average or above average attentiveness and knowledge.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.197-203
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• 2010

The data of average temperature, average relative humidity, precipitation and average wind speed were collected from 674 meteorological stations in China. A specific procedure that processes original data into a new data format needed in forest fire danger rating forecast system of China was introduced systematically, and the feasibility of this method was validated in this paper. In addition, a set of meteorological data processing software was constructed by the secondary development of GIS in order to realize automation of processing data for the system. Results showed that the approach preformed well in handling temperature, average relative humidity and average wind speed, and the processing effect of precipitation was acceptable. Moreover, the automated procedure could be achieved by GIS and the working efficiency was about 3 times as much as that of manual handling. The informationization level of processing meteorological data was greatly enhanced.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.2
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• pp.157-165
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• 1999

Grain size of steels is one of the most important parameters which influence yield strength and fracture toughness. Ultrasonic wave propagating in polycrystalline materials is mostly attenuated by scattering at grain boundary. Effect of ultrasonic attenuation on average ferrite grain size of carbon steels with tensile strength $40{\sim}60kgf/mm^2$ consisting of multi phases such as ferrite + pearlite and ferrite + pearlite + bainite was evaluated. The attenuation of these steels rapidly increased with average ferrite grain diameter. Average ferrite grain diameter ($D_{av}$, ${\mu}m$) could be expressed as $1.79+22.97*a^{1/2.03}$, where a is attenuation with unit of nepers/cm. From this study, it was confirmed that nondestructive ultrasonic method could be used in measuring average ferrite grain size indirectly.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.3
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• pp.207-221
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• 2020

This study conducted a meta-analysis on the effects of innovation, risk-taking, and enterprising on entrepreneurship. From 2013 to 2020, 392 papers, which were judged as quantitative research from doctoral and master thesis, and academic journals published in Korea were selected as research subjects. 28 duplicates of thesis and thesis are excluded. A total of 52 papers were finally selected, excluding 312 papers that were insufficient to be used as research data because there were no statistical values such as correlation coefficients. For the 52 selected papers, the homogeneity of the variables was first verified. As a result of the homogeneity test, the innovativeness, risk-taking, initiative, and entrepreneurship education all showed great effects on heterogeneity, and the average effect size was analyzed by random effect model. The average effect size analyzed was 0.38 ~ 0.49, and all four variables showed moderate average effect size. As a result of analyzing the average effect size by forest plot, all showed proper results. From the results of funnel plot analysis of entrepreneurship education, published errors were confirmed asymmetric. Research data on entrepreneurship education shows that it cannot represent the whole. It is a structural equation model with entrepreneurship and entrepreneurial intention as a parameter. Iinnovation and risk-taking have an impact on entrepreneurship by taking entrepreneurship education as a parameter. Initiative had an effect on the entrepreneurial intention a business, regardless of entrepreneurship education. In a number of studies, university entrepreneurship education has had an impact on the entrepreneurial intention. It should be changed to entrepreneurship education that combines theory and practice. Entrepreneurship education should be transformed into continuous and field-oriented education.

• Journal of the Korean Society of School Health
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• v.27 no.3
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• pp.130-139
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• 2014

Purpose: The object of this study was to compare the educational effect about self-efficacy and the quality of chest compressions of Hands-only CPR and Basic CPR. Methods: It's a nonequivalent control group pre-post repeated quasi-experiment study conducted with entire fifth grade students belong to one school in H city. The study participants are 68 persons, and data were collected from December 2, 2013 to February 7, 2014. Self-efficacy was measured by 10 items, and the quality of chest compressions was measured by 5 variables which are average compression depth(mm), average rate (n/min), average count per minutes (n), abnormal placement (n), compression accuracy (%). Results: Self-efficacy of the experimental group and control group showed no significant difference but showed significant difference over time and was the highest at posttest 1 (immediately after education), the lowest at pretest (before education), middle at posttest 2 (8weeks after education) (p<.001). Experimental group was significantly higher than control group in average rate per minute. At posttest 1, experimental group was $130.0{\pm}9.38$ times, control group was $95.1{\pm}11.82$ times. At posttest2, experimental group was $124.0{\pm}14.89$ times, control group was $90.8{\pm}14.89$ times.(p<.001). Average rate (n/min) was significantly declined at control group in the quality of chest compressions over time (t=-2.400, p=.022). Average count per minute and compression accuracy were declined significantly so it were not maintained to posttest2. Conclusion: We need continuous CPR education because self-efficacy of CPR getting lower significantly over time. Hands-only CPR can't be seen as a way to increase the CPR ability of elementary school students having difficulty to perform artificial breathing. And, because the effect of education is not maintained 8wks after training, the technique centered repeated training is needed and a method which can increase compression accuracy is also needed.

• Transactions of Materials Processing
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• v.29 no.3
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• pp.127-134
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• 2020

It is known that the difference of texture of the polycrystalline Al sheet is not a critical parameter for the formation of aligned nanopore arrays in anodic aluminum oxide (AAO). This will be related to the polycrystalline grain in the Al sheet. The texture of each grain in the polycrystalline Al sheet is different. The mixed textures of grains have the mixing effects on the nanopore structure of the AAO. Thus, the effect of Al texture on the nanopore structure of the AAO was investigated using three types of Al single crystals with (111), (200) and (220) textures in this paper. These three types of AAO layers were fabricated by the two-step anodizing method at 40 V and temperature of 0-5℃ in oxalic acid solution. In the nanopores formed on the AAO, the average area of one nanopore and the average roundness of one nanopore were measured were measured based on the SEM images. In the hexagon obtained by connecting nanopores on the AAO, the average standard deviation of one angle deviated from 120° was measured. In the AAO nanopores with texture of (111), (200) and (220) single crystal samples, the average area of one nanopore of (200) single crystal sample was the widest, followed by (111), (220) single crystals. The average circularity of one nanopore of (200) single crystal sample was the best, followed by (111), (220) single crystals. The average standard deviation of an angle from 120° of (220) single crystal sample was the largest, followed by (111) and (200) single crystals.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.7-12
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• 1997

This study was intended to investigate the proper shape and size of calcium carbonate for the improvement of paper properties and its end use performance. We loaded calcium carbonate of various shapes and size in the handsheet and measured their physical and optical properties. Results obtained from the study are summarized as follows : 1. Due to different particle shapes and sizes, precipitated calcium carbonate (PCC) contributed greater to bulk improvement than ground calcium carbonate (GCC). Scalenohedral form of PCC produced the bulkiest sheet, GCC made the sheet bulkier as average particle size increases. 2. Tensile strength increased as average particle size was increasing. GCC kept tensile strength more effectively than PCC. The effect of particle size on tensile strength was much more pronounced as filler addition level was increasing. 3. Over the average particle size of 6.99$\mu$m, GCC gave much higher burst strength and internal bond than PCC did. In the filler levels of 20% and 30%, GCC by using bigger size fillers showed 50~100% improvement in some cases than PCC at the same filler content. 4. Tear strength increased as average particle size was increasing. At the filler level of 30%, PCC decreased tear greatly. 5. Over the average particle size of 13.56$\mu$m, GCC kept bending stiffness greater than PCC. Due to its shape, Scalenohedral form of PCC showed higher stiffness than others at the same particle size. 6. Cubic and acicular form of PCC improved light scattering coefficient very effectively. Light scattering coefficient of GCC decreased as average particle size increased. 7. Both of particle shape and size of filler were important factor in developing optical properties and bending stiffness. Particle size was the only important factor in developing other strength properties

• Journal of the Korean Society of School Health
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• v.30 no.3
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• pp.317-324
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• 2017

Purpose: Breakfast is the most important meal to provide energy for the day. Breakfast is especially important to give enough nutritional support to children and adolescents for their physical growth and sexual development. Sleep-related factors like average sleep duration and wake up time would mostly be associated with regular breakfast. This study aimed to investigate the effect of sleep on regular breakfast consumption in Korean adolescents. Methods: The study used the data from the 12th Korea Youth Risk Behavior Web-based Survey (KYRBS-XII) conducted in 2016 by the Korea Centers for Disease Control and Prevention. The data of 62,820 subjects (middle/high school students) were included in the final analysis. The study examined the factors related to regular breakfast, focusing on weekday average sleep duration and wake up time of middle school students and high school students, respectively. Results: Regular breakfast consumption was shown to have a statistically significant association with high economic status, nutritional education, weekday average sleep duration, wake up time, and subjective sleep satisfaction in the multivariate logistic regression. Regardless of the school level, regular breakfast consumption was significantly associated with early wake up time. As to the effect of weekday average sleep duration on regular breakfast consumption, it showed some different results depending on the school level. Conclusion: Regular breakfast consumption of Korean adolescents was related to weekday average sleep duration and wake up time. Having breakfast regularly was affected by both adequate weekday average sleep duration and early wake up time.

• Journal of KIISE:Databases
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• v.36 no.4
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• pp.327-340
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• 2009

To achieve the noise reduction effect in boundary image matching, we use the moving average transform of time-series matching. Our motivation is based on an intuition that using the moving average transform we may exploit the noise reduction effect in boundary image matching as in time-series matching. To confirm this simple intuition, we first propose $\kappa$-order image matching, which applies the moving average transform to boundary image matching. A boundary image can be represented as a sequence in the time-series domain, and our $\kappa$-order image matching identifies similar images in this time-series domain by comparing the $\kappa$-moving average transformed sequences. Next, we propose an index-based matching method that efficiently performs $\kappa$-order image matching on a large volume of image databases, and formally prove the correctness of the index-based method. Moreover, we formally analyze the relationship between an order $\kappa$ and its matching result, and present a systematic way of controlling the noise reduction effect by changing the order $\kappa$. Experimental results show that our $\kappa$-order image matching exploits the noise reduction effect, and our index-based matching method outperforms the sequential scan by one or two orders of magnitude.