• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.67-76
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• 2021

Biogasification is a technology that produces environmentally friendly fuel using methane gas generated in the process of stably decomposing and processing organic waste. Biogasification is the most used method for energy conversion of organic waste with high moisture content, and is a useful method for organic waste treatment following the prohibition of direct landfill (2005) and marine dumping (2013). Due to African Swine Fever (ASF), which recently occurred in Korea, recycling of wet feed is prohibited, and consumers such as dry feed and compost are negatively recognized, making it difficult to treat food waste. Accordingly, biogasification is attracting more attention for the treatment and recycling of food waste. Korea's energy consumption amounted to 268.41 106toe, ranking 9th in the world. However, it is an energy-poor country that depends on foreign imports for about 95.8% of its energy supply. Therefore, in Korea, the Renewable Energy Portfolio Standard (RPS) is being introduced. The domestic RPS system sets the weight of the new and renewable energy certificate (REC, Renewable energy certificate) of waste energy lower than that of other renewable energy. Therefore, an additional incentive system is required for the activation of waste-to-energy. In this study, the operation of an anaerobic digester that treats food waste, food waste Leachate and various organic wastes was confirmed. It was intended to be used as basic data for preparing the waste-to-energy incentive system through precise monitoring for a certain period of time. Four sites that produce biogas from organic waste and use them for power generation and heavy gas were selected as target facilities, and field surveys and sampling were conducted. Basic properties analysis was performed on the influent sample of organic waste and the effluent sample according to the treatment process. As a result of the analysis of the properties, the total solids of the digester influent was an average of 12.11%, and the volatile solids of the total solids were confirmed to be 85.86%. BOD and CODcr removal rates were 60.8% and 64.8%. The volatile fatty acids in the influent averaged 55,716 mg/L. It can be confirmed that most of the volatile fatty acids were decomposed and removed with an average reduction rate of 92.3% after anaerobic digestion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.460-470
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• 1985

Experiments were carried out to evaluate the standard gravity in determining potential kernel size and to determine the effective sampling way by analyzing intra - and inter - plant variations for some source and sink characters using eleven semi-dwarf indica and three japonica cultivars including four semi-dwarf indica nearisogenic lines. Also, additional experiments were conducted to understand yearly variation and variety x year interaction effects for ten characters related to source and sink and to characterize the varietal difference of pre- and post-heading self-competition employing three parental varieties and their F$\sub$5/ progenies in 1982 and 1983. It is desirable to determine the potential kernel size by average kernel wight of rice grains showing above 1.15 specific gravity. There was significant difference in leaf area per tiller, spikelets and sink capacity per panicle among vigorous, intermediate and inferior tillers classified by differentiated order and vigorousness. Although it was difficult to find out any significant difference in grain-fill ratio, ratio of perfectly ripened grain, potential kernel size and sink/source ratio between vigorous and intermediate tillers, there was big difference between them and inferior one. The coefficients of variation within each tiller-group for some characters related to source and sink were larger with the order of vigorous tillers < intermediate one '||'&'||'lt; inferior one, and the average heritability of all characters, evaluated by the ratio of varietal variance (equation omitted) to total variance (equation omitted), were higher with the order of inferior tillers '||'&'||'lt; intemediate one '||'&'||'lt; superior one. Therefore, it is desirable to sample the vigorous tillers to represent the varietal difference of these traits. '82-'83 year variations of three parental cultivars were significant for all traits except for leaf area/tiller, panicles/hill, leaf area index and rough rice yield. The characters showing highly significant variance of variety x year interaction were growth duration from transplanting to heading, leaf area/tiller, sink/source ratio, sink capacity/panicle and grain yield. Generalized yearly response of three parental varieties (Suweon 264, Raegyeong, IR1317-70-l) and their F$\sub$5/ progenies on the 1st and 2nd principal components extracted from ten source and sink characters generally exhibited reduction in both source and sink. However, there were diverse variety x year interactions such as progenies showing similar reaction with their parents and intermediate or recombinational yearly response with little or considerable yearly movement on the four-dimensional planes of the two upper principal components between 1982 and 1983. Sink characters revealing highly significant border effect were grain-fill ratio, spikelets and sink capacity per panicle. Among them the latter two especially showed significant variety x border effect interaction. Self-competition characterized by relative weakness of inside plant's sink characters compared to the border one was more severe during the reproductive stage before heading than maturing stage. Though the larger sink capacity per panicle generally disclosed the severer self-competition, some lines (like Suweon 264) revealed severe self-competition with small sink capacity while a few others showed tender self-competition in spite of big sink capacity per panicle.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.725-733
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• 2012

This research, targeting the college students majoring in health administration science in Kwangju & Chonnam, is aimed at understanding their satisfaction with majors according to general, relationship, consciousness, and subject satisfaction, and looking into the correlation between the satisfaction and further career choices. This research set the 270 prospective graduates its study subjects based on convenience sampling. It was found that the number of students who want to choose their further major-related careers as medical records technician was greatest among the research subjects, of whom 62.4% were satisfied with their major subject while there existed a little difference in major satisfaction by further career. In addition, the students who want to choose the career of medical records filer showed higher satisfaction with their major subject than those who want to choose other-major-related careers. In general characteristics among the influential factors of major satisfaction in major-related career choices of a students of health administration science department, the 2nd year classes' major satisfaction was found to be 4.13 times as high as the 3rd year classes while the major satisfaction of the group choosing their major subject spontaneously was found to be 8.04 times as significantly high as the group choosing their major subject involuntarily. As a result of the analysis of the influence on major satisfaction among the sub-province of major satisfaction, it was found that the group having high consciousness satisfaction was 3.93 times as significantly high as the group having low consciousness satisfaction. A logistic analysis of the influence of major satisfaction on further career choices, the major satisfaction of those wishing to choose their major-related career as a medical records technician was 2.06 times as significantly high as those who didn't choose a medical records filer as their career choice while the major satisfaction of the group spontaneously choosing the career of a medical records technician was 4.51 times as significantly high as that of the group involuntarily choosing the career of a medical records technician. There should be a plan for enhancing major satisfaction by each major-related career in consideration of the characteristics of health administration science department having diverse career choices.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.665-676
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• 2003

To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

• Journal of Music and Human Behavior
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• v.4 no.2
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• pp.18-40
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• 2007

The purpose of this study was to verify the influence of musical activities on social and emotional behavior of infants, through providing musical activities to the infants who were cared in a nursery and observing the interactions between peer group, or a therapist and an infant derived during them. The subject is 24 infants who are under 2 years of age(25~36months) at two nurseries located in Bundang area, and 13 infants among them are randomly assigned as study group and 11 infants as control group. Pretest and posttest about social and emotional behavior are performed, and ITSEA developed by Brggs-Gowan and Carter(2001) and amended by Shin Ji Yeon(2004) was used as an evaluation tool. Infants' changes of interaction behaviors during musical play were also analyzed quantitatively and qualitatively, and for the analysis, infant's social play behavior examination tool developed by Holloway and Reichhart-Erickson(1988) was adopted. Based on time sampling method, each item of this tool was evaluated. Each session was performed for 15 minutes, and 60 times of analysis about interactions per session was conducted at every 15 seconds. The analysis result was showed with a table and a graph, and described qualitatively about behavior changes. When compared social and emotional positive behavior average figures and negative behavior average figures between study group and control group, this study showed that the positive behavior figure of study group was increased and the negative behavior figure was decreased. While concentration and empathy among positive behaviors increased meaningfully, aggression, defiance, separation anxiety and rejection to new things among negative activities also decreased meaningfully. The conclusion of this study is as follows. First, interactions with peers or a therapist based on music and musical experience make an effect on strengthening positive behavior among social and emotional behavior and decreasing negative behavior. Second, music has influence on negative behaviors more than positive behaviors of an infant, and produces a good effect on sub behaviors of negative behaviors specially.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.47-57
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• 2009

Objectives: The purpose of this study was to identify the health promotion behavior, health problem, perceived health status and farmers' syndrome of rural residents. Methods: The subjects of this study were 637 adults of 19 primary health care post extracted from 1.875 primary health care post in Korea by quota sampling method. The collected data were analyzed by descriptive statistics, Pearson's correlation. Results: The average score of health promotion behavior was 2.23. In the sub-scales, the highest degree of performance was 'nutrition', followed by 'spiritual growth' and the lowest degree of performance was 'physical activity'. The most prevalent health problem was ailments in 'musculoskeletal system', followed by 'fatigue', 'eyes and ears', 'cardiovascular system'. The mean score of perceived health status was 8.54. The prevalence of farmers' syndrome was 98.4%. Health promotion behavior showed a significant positive correlation health status and perceived health status showed a significant negative farmers' syndrome. Conclusions: With the above findings, rural residents' physical activity is less than urban residents', and the rural resident's score of perceived health status, musculoskeletal system and fatigue are lower than urban residents'. The farmers' syndrome of the rural people is high. A tailored health promotion program for rural community is needed to develop in the consideration of these findings.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.230-240
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• 2017

BACKGROUND: To evaluate residues of environmentally concerned pesticides in water system, this monitoring was conducted over three rivers. The residual characteristics and discharging condition of these residues on water system was investigated. METHODS AND RESULTS: Total twenty nine sampling sites were selected through main streams and branch streams of Keum, Mangyung and Dongjin rivers, and the water samples from them were regularly collected one month interval, especially biweekly from May to August in 2002. Of the pesticides monitored, six fungicides which include hexaconazole, isoprothiolane and iprobenfos were detected with frequencies of 0.3-50.9% and in their residue level of $0.1-4.7{\mu}g/L$. Sixteen insecticides which include nine organophosphoruses, three carbamates, endosulfan, cypermethrin, buprofezin and fipronil were detected with frequencies of 0.3-32.5% and in their residue level of $0.01-2.8{\mu}g/L$. Nine herbicides which include alachlor molinate, anilofos, butachlor, dimepiperate, metolachlor, oxadiazon, pretilachlor and thiobencarb were detected with frequencies of 0.8-22.9% and in their residue level of $0.01-9.07{\mu}g/L$. CONCLUSION: Detection frequencies and residue levels of insecticides and herbicides were the highest in waters sampled in May and June. Almost pesticides detected were for the paddy rice and their residue levels were very low to compare with standard values.

• Journal of The Korean Association For Science Education
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• v.36 no.4
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• pp.705-715
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• 2016

The purpose of this research is to analyze elementary students' attention characteristics through attention test and eye tracking on real science classes. The SMI's ETG(eye tracker glasses) mobile eye tracker was used to analyze the attention process of elementary students'. The sampling rate of the ETG is 30Hz. The participants of attention test were elementary 155 6th-grade elementary students and the participants for the eye-tracker were six 6th-grade male students. The eye movements were analyzed using the 'BeGaze Mobile Video Analysis Package' program. The results of this research are as follows. First, the attention test results of elementary students showed high correlation between selective attention and sustained attention (.85) and low correlation between selective attention and self-regulation (.32). Second, the attention types of elementary students were divided into four; attention, inattention, easygoing and hasty. Third, elementary students' attention were divided into top-down, bottom-up, default mode network through analysis of elementary students′ eye-movements during real science classes. Also their attention shift occurred frequently due to various reasons in real class situation. There were three reasons that made elementary students fail to handle knowledge-dependent top-down attention; 1) the cognitive failure of target caused by failing to focus attention, 2) the absence of prior knowledge on target object, 3) the analogical failure of prior knowledge. Finally, elementary students' attention process were schematized based on the analysis of students' eye movements and attention test. This research is expected to be utilized as basic data for developing effective teaching strategies, teaching-learning models and instructional materials.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.173-182
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• 2007

It is well known that manganese nodules enriched with valuable metals are abundantly distributed in the abyssal plain area in the Clarion-Clipperton (C-C) fracture zone of the northeast Pacific. Previous studies using deep-sea camera (DSC) system reported different observations about the relation of seafloor topographic change and nodule abundance, and they were sometimes contradictory. Moreover, proper foundation on the estimation of DSC underwater position, was not introduced clearly. The variability of the mining condition of manganese nodule according to seafloor topography was examined in the Korea Deep Ocean Study (KODOS) area, located in the C-C zone. In this paper, it is suggested that the utilization of deep towing system such as DSC is very useful approach to whom are interested in analysing the distributional characteristics of manganese nodule filed and in selecting promising minable area. To this purpose, nodule abundance and detailed bathymetry were acquired using deep-sea camera system and multi-beam echo sounder, respectively on the seamount free abyssal hill area of southern part ($132^{\circ}10'W$, $9^{\circ}45'N$) in KODOS regime. Some reasonable assumptions were introduced to enhance the accuracy of estimated DSC sampling position. The accuracy in the result of estimated underwater position was verified indirectly through the comparison of measured abundances on the crossing point of neighboring DSC tracks. From the recorded seafloor images, not only nodules and sediments but cracks and cliffs could be also found frequently. The positions of these probable unminable area were calculated by use of the recorded time being encountered with them from the seafloor images of DSC. The results suggest that the unminable areas are mostly distributed on the slope sides and hill tops, where nodule collector can not travel over.

• The Korean Journal of Coaching Psychology
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• v.5 no.2
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• pp.127-170
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• 2021

This study developed a measure to measure wellness-seeking behavior in important areas of life for general adults in Korea and verified its validity. For the development of the wellness scale, 31 factors derived through literature review, expert interviews, in-depth interviews, open questionnaires 1 and 2, and 182 questions were selected as the final 10 factors and 99 questions. Through exploratory factor analysis of the results of the preliminary survey of 351 adults in Korea, 58 questions of 10 factors were derived, and some of the questions reflecting important concepts in each factor were revised, and this survey was conducted with 63 questions of 10 factors. In this survey conducted on 667 people, to verify the validity of the composition concept of this test, the entire sampling was divided into two groups, one group was subjected to exploratory factor analysis, and the other group was subjected to confirmatory factor analysis. As a result of exploratory factor analysis, 63 questions of 10 factors (work, community, family, others, economic power, self-esteem, leisure, physical health, spirituality, and self-growth) were finally derived, and confirmatory factor analysis using the structural equation model verified that the model fit criteria were met. Convergence validity was verified using the K-MHC-SF and Wellness Index for Workers to verify whether the derived wellness scale and its sub-factors actually measure wellness. As a result of analyzing the relationship between the variables and factors of the Subjective Happiness Scale and Life Scale to verify the validity related to the criteria, it was found to be a significant correlation. As a result of confirming the significance of each path through multiple regression analysis, the 'self-esteem' on the wellness scale was identified as the most important factor influencing subjective happiness and life satisfaction. Finally, discussions on this research process and results, academic significance and practical significance, limitations, and future research directions were presented.