• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.723-730
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• 2017

The batch experiments by response surface methodology (RSM) have been applied to investigate the influences of operating parameters such as temperature, initial concentration, contact time and adsorbent dosage on 2,4-dichlorophenol (2,4-DCP) adsorption with an activated carbon prepared from waste citrus peel (WCAC). Regression equation formulated for the 2,4-DCP adsorption was represented as a function of response variables. Adequacy of the model was tested by the correlation between experimental and predicted values of the response. A fairly high value of $R^2$ (0.9921) indicated that most of the data variation was explained by the regression model. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. These results showed that the model used to fit response variables was significant and adequate to represent the relationship between the response and the independent variables. The kinetics and isotherm experiment data can be well described with the pseudo-second order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of 2,4-DCP on WCAC calculated from the Langmuir isotherm model was 345.49 mg/g. The rate controlling mechanism study revealed that film diffusion and intraparticle diffusion were simultaneously occurring during the adsorption process. The thermodynamic parameters indicated that the adsorption reaction of 2,4-DCP on WCAC was an endothermic and spontaneous process.

• Journal of Global Scholars of Marketing Science
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• v.7
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• pp.283-302
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• 2001

The purpose of this study was to examine the current situation about the internet usage and advertisement attitude, to investigate the relationship between consumer characteristics and internet advertising effect, and to identify the moderating effect of consumer characteristics on the relationship between advertising types and advertising effects. For the study, a sample of 152 apparel consumers participated in this survey research. The survey of design with a questionnaire was employed. Questionnaire was developed with the html language and data collection was done at Korea though the internet on October 2000. For data analysis, descriptive statistics (i.e., frequency, percent), ANOVA with duncan tests were used. First, the major place of using internet was found as home, company, school, PC room in order and the average time of using internet was found as three times weekly. The major purpose of using internet were information search, e-mail, PC communication and program-download. The experience of internet fashion advertising was high. Second, consumer characteristics(age, job) had significant effects on attitude to the product. 20 years-old age group and specialist group were found to influence on the higher attitude toward product. Third, main effects of consumer characteristics(age, job) were found to be significant. The correlation and interaction effects of consumer characteristics and internet advertisement types were not significant.

• Korean Journal of Remote Sensing
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• v.36 no.5_4
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• pp.1179-1194
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• 2020

This study investigates the feasibility of three algorithms, K-Nearest Neighbors (K-NN), Random Forest (RF) and Neural Network (NN), for estimating the air temperature of an unobserved area where the weather station is not installed. The satellite image were obtained from Landsat-8 and MODIS Aqua/Terra acquired in 2019, and the meteorological ground weather data were from AWS/ASOS data of Korea Meteorological Administration and Korea Forest Service. In addition, in order to improve the estimation accuracy, a digital surface model, solar radiation, aspect and slope were used. The accuracy assessment of machine learning methods was performed by calculating the statistics of R² (determination coefficient) and Root Mean Square Error (RMSE) through 10-fold cross-validation and the estimated values were compared for each target area. As a result, the neural network algorithm showed the most stable result among the three algorithms with R² = 0.805 and RMSE = 0.508. The neural network algorithm was applied to each data set on Landsat imagery scene. It was possible to generate an mean air temperature map from June to September 2019 and confirmed that detailed air temperature information could be estimated. The result is expected to be utilized for national disaster safety management such as heat wave response policies and heat island mitigation research.

• Journal of The Korean Society of Clinical Toxicology
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• v.5 no.1
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• pp.27-35
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• 2007

Purpose: Organophosphate (OP) compounds insecticides are the most commonly associated with serious human toxicity all over the world. The aim of this study was to identify sociocultural factors that contribute to high incidence of pure OP poisoning and prevent OP poisoning in order to reduce the factors responsible for deaths in South Korea. Methods: This is the 38 multi-centers survey and prospective study of pure OP poisoning by structural reporting system and hospital records from August 2005 to July 2006. 238 patients with acute pure OP poisoning were enrolled. We collected patient information regarding poisoning, clinical, and demographic features. Results: The mean age was $55.32{\pm}17.3$ years old. The most frequent site of exposure was their own residence(85.7%). Frequent compounds involving pure OP poisoning were dichlorvos(22.7%), methidathion(8.4%), and phosphamidon(6.7%). Intentional poisoning was 77.9%. The most frequently route of exposure was ingestion(94.5%). The mean arrival time to hospital after poisoning was 12.7 hours and mean hospitalization duration was 12.9 days. 2-PAM was administered to 101 patients in mean doses of 6.3 g/day intravenously. Atropine was administered to 81 patients in mean doses of 74.6 mg/day (maximal 910 mg/day). The presence of lower level of GCS score, respiratory complications, hypotension, acute renal failure, and serious dysrhythmia was associated with serious and fatal poisoning. Overall final mortality in pure OP poisoning was 9.7%(23/238). Conclusion: This study highlights the problem of pure OP poisoning in South Korea as a basic national survey. Futhermore this might help the establishment of strict policies availability of OP and the statistics of OP poison exposure in South Korea.

• Research in Community and Public Health Nursing
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• v.13 no.4
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• pp.743-756
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• 2002

Purpose: This study is a descriptive and comparative study that compares health state and school adaptation between children in divorced family and in normal family. Study results will provide a basic data for the development of an intervention program designed to help children in divorced family adjust to their crisis. Method: The study subjects consisted of 700 children in 4th. 5th or 6th elementary school grade, residing Seoul and Kyunggi regions. Among these subjects, 123 were children with divorced family and 577 were children with normal family. The health status of the subjects was measured by Health Symptom Questionnaire developed by Shin and revised by the investigators. The instrument consisted of 30 items measuring physical and emotional health symptoms. The level of school adaptation of the subjects was measured by School Adaptation Scale developed by Lee, which consisted of 4 dimensions with 20 items what measures relationship with peer students, learning activity, observance of regulation, and participation of school activity. The investigators visited the schools and collected data in the classes using the questionnaire after explaining the purpose and procedures of the study to the children. The data were analyzed by descriptive statistics, $\yen\"{o}2$-test, t-test, ANOVA using the SPSS PC + statistical program. Result: First, the mean health state score in children with normal family (M=11.99) was higher than that in children with divorced family (M=19.15), showing a significant difference (t=-6.51, p=.000) between the two groups, which suggests that children with normal family have better health state than children with divorced family. Second, the mean school adaptation score in children with normal family (M=38.99) was higher than that in children with divorced family (M=26.97), showing a significant difference between the two groups (t=104.07, p=.000), which suggests that the school adaptation of children with normal family is better than that of children with divorced family. Third, in comparison of health state between the two groups by general characteristics. there were significant differences between the two groups in sex. the most contributing factor to health status of the children, school year. birth order, religion, school achievement, amount of monthly pocket money, parents level of formal education, occupation of parents, economic status (p<.05). Forth, in comparison of the level of school adaptation between the two groups by general characteristics, there were significant differences between the two groups in most variables (p<.05), suggesting that children with normal family had better capacity of school adaptation than children with divorced family. Conclusion: As a result. this study showed that the parent's divorce had great influence on children's health status and school adaptation capacity. The implication for nursing is that there is a need to develop supportive interventions for the high-risk children who have decreased health states and school adaptation capacity due to the divorce of their parents. In addition, it is recommended that further studies should be conducted to explore protective factors for the prevention of health and adaptation problems in children.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1612-1612
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• 2001

The production of grain for export and domestic use is one of Australia's most important agricultural industries, and the NIR technique has been used extensively over many years for the routine monitoring of grain quality, particularly moisture and protein content. Because most Australian grain is intended for human food production, the determinants of grain quality for livestock feed, apart from protein, have been largely ignored. However the increasing use of grain for feeding to pigs, poultry, beef cattle and dairy cows has led to an important national research project entitled “Premium Grains for Livestock”. Two of the objectives of this project are to determine the compositional and functional characteristics of grains which influence their nutritional quality for the various classes of livestock, and to adopt rapid and objective analytical tests for these quality criteria. NIR has been used in this project firstly to identify a set of grain samples from a large population of breeders' lines which showed a wide spectral variation, and hence a potentially wide variation in nutritional value. The selected samples were not only subjected to an extensive array of chemical, physical and in vitro analyses, but also were grown out to produce sufficient quantities of grain to feed to animals in vivo studies. Additional grains were also strategically selected from farms in order to include the effect of weather damage, such as rain, drought and frost. In this study to date, NIR calibrations have been derived or attempted, on both ground and whole grains, for in vivo dry matter digestibility (DMD), pepsin-cellulase dry matter disappearance, protein, fat, acid detergent fibre, neutral detergent fibre, starch, in sacco DMD and in vitro assays to simulate starch digestion in the lumen and small intestine. Results so far indicate high calibration accuracy for chemical components (SECV 0.3 to 2.6%) and very promising statistics for in vivo DMD (SECV 1.8, $R^2$ 0.93, SD 7.0, range 61.9 to 92.3, n=60). There appears to be some potential for NIR to estimate some in vitro properties, depending upon the accuracy of reference methods and appropriate sample populations. Current work is in progress to extend the range of grains with in vivo DMD values (a very laborious and expensive process) and to increase the robustness of the various NIR calibrations, with the aim of implementing uniform testing procedures for nutritional value of grains throughout Australia.

• Research in Community and Public Health Nursing
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• v.13 no.2
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• pp.376-386
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• 2002

Objectives: The purpose of this study was to investigate factors influencing the smoking behavior of adolescents, in order to provide basic data to develop a future nursing intervention program for smoking prevention. Methods: The study subjects were 162 adolescents attending high schools, who were living in K city. The instruments included the Self Esteem Scale translated by Jeon (1974), beliefs about the social rule scale developed by the Committee for Adolescence Guidance (1988), differential peer association developed by Krohn et. al. (1982), perceived behavioral control scale developed by Hanson (1997), intention of smoking scale developed by Newman et. al.(1982), and self-efficacy scale developed by Sherer et. al. (1982). The data were analyzed using descriptive statistics, Pearson correlation coefficient, and stepwise multiple regression. Results: 1. The smoking behaviors of the subjects were significantly correlated with beliefs about social rule, perceived behavioral control. differential peer association, intention of smoking, self efficacy, grade, father's level of education, monthly pocket money, time of onset for smoking, degree of alcoholic intake, and drug abuse. 2. The multiple regression analysis revealed the most powerful predictor for smoking behavior was time of onset for smoking. A combination of beliefs about social rule, perceived behavioral control, grade, differential peer association, and intention of smoking accounted for 54.0% of the variance for smoking behavior in adolescents. Conclusion: It is recommended that these influencing factors for smoking behavior be considered when developing future nursing intervention programs for the antismoking behaviors of adolescents.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.3
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• pp.27-33
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• 2012

According to the statistics of the Ministry of Environment, the emission of sewage sludge is increased by 7~9% yearly. In the future, it will be increased continuously because of extension of sewage disposal plants, high class treatment for removing nitrogen and phosphorus. Until now, we have depended on reclamation for lots of quantity and some part has been treated by ocean emission. But, direct reclamation of organic waste will be prohibited and even ocean emission will be prohibited now, so the treatment of sludge is put on emergency alert. Bio-gas can be produced by applying anaerobic digestion method for the recycling or refuse derived fuel can be conducted by applying carbonization method. However, the process is difficult, causes bad smell and makes it the second waste, so it cannot be practical method in fact. This study applied a fluidized bed combustor for sewage sludge treatment technologies that can actually take advantage of key technologies in order to verify its purpose is to demonstrate selected. If applying the fluidized bed combustor, it can be easily utilized as the replaced resource of energy(fuel) in the countries whose energy resources are insufficient, like our country. Especially, if applying only original strengths of the fluidized bed combustor sufficiently, the sewage sludge can be treated simply, eco-friendly, sanitarily and economically. Particularly, it is verified as the energy technology suitable for government's green growth policy.

• Journal of Engineering Education Research
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• v.8 no.3
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• pp.57-68
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• 2005

The purpose of this study was to analyze the effect of Engineering computer programming instruction using project learning, to find out the ways to solve some revealed problems, and to improve the instruction. Unlike traditional lecture courses, students are encouraged to cultivate problem solving and teamwork skills through the programming project. In order to examine the effect of project learning, a survey was conducted with 49 students. The questionnaire consisted of 20 items with 5-grade scale each, the contents of which included learning value, workload, skills acquirement, assignment and comment. The SPSS, statistical analysis software was used to get statistics such as ANOVA, correlation and mean, etc. The results of this study showed (1) project learning was more efficient to acquire problem solving and teamwork skills compared with lecture learning, (2) there was significant correlation between self directed learning skill and information collecting skill, (3) cyber education system(i-campus) was helpful for students' self learning. But the results also showed that (4) students did not give high scores on items of the workload or difficulty of assignments. So we can conclude that it is necessary to develop the suitable projects for the capability of students to make the better project learning.

• The Journal of the Korea Contents Association
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• v.20 no.8
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• pp.572-582
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• 2020

The purpose of this study was to investigate workplace bullying, job stress, organizational commitment, and turnover intention as well as determine influencing factors on the turnover intention of small and medium-sized hospital nurses. Participants included 140 nurses from six small and medium-sized hospitals with less than 300 beds in G-city and J-province. Data were analyzed using descriptive statistics, independent t-test, one-way analysis of variance, Pearson's correlation coefficient, and stepwise multiple regression, using the SPSS Win 21.0 program. The regression model was statistically significant (F=37.11, p<.001), and the explanatory power for turnover intention was 34.2%. The significant factors influencing turnover intention were organizational commitment (β=-.41, p<.001 and job stress (β=.25, p=.005). Human resources management is crucial for providing high quality healthcare service. The results of this study indicated that it is important to lower job stress and increase organizational commitment in order to reduce turnover intention among nurses of small and medium-sized hospitals. Based on these findings, customized programs for nurses in small and medium-sized hospitals need to be developed and implemented so as to lower their turnover intention and promote efficient management of healthcare human resources.