• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.262-268
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• 2007

To characterize morphological classification of the basins, four major basin characteristics of the unit basins, including sinuosity, ratio of forest, ratio of flat area, and tributary existence were selected for cluster analysis. The analysis was carried out using soil map, topographic map, water course map, and basin map of the fifty unit basins in the Yeongsangang Basin. The unit basins could be categorized to five basin groups. The fitness by the Mantel test showed good fit of which r was 0.830. These grouping based on comprehensive soil and topographic characteristics provides best management practices, water quality management according to pollutants, increased water related model application and reasonable availability of water management. For agricultural management of water resources and conservation of water quality from agricultural non-point pollutants, therefore, comprehensive systematic classification of soil characteristics on unit basin might be an useful tool.

• Journal of the Korean Dietetic Association
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• v.3 no.1
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• pp.9-22
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• 1997

Purposes of the study were to : (a) measure the levels of job satisfaction, (b) investigate the degree of job characteristics, (c) determine the levels of organizational commitment, (d) investigate relationships between demographic variables and job satisfaction, and (e) examine the relationship between organizational commitment, job characteristics and job satisfaction. Questionnaire was developed and mailed to 300 dietitians who are currently working in school, hospital and industry foodservices. A total of 177 questionnaires were usuable : resulting in a 59% response rate. Results of this study were summarized follows : 1. Approximately half of the respondents(46.9%) indicated that the were 26 to 30 years old. A total of 112 respondents(63.3%) were unmarried. A bachelor's degree was reported as the most common education level(46.9%) while 6.2% of the participants reported a master's degree. Years of employment in professional practices were ranged from 2 to 5. Approximately 40% of the respondents had earned over \900,000 per month. 2. Work itself of the JDI was with the highest job satisfaction mean score followed by supervision, co-workers, wage and promotion. 3. In total job satisfaction score, dietitians in school foodservices were a significant lower than dietitians in industry foodservices and hospital foodservices. 4. A significant relationship was found for demographic factors and four job facets in terms of job itself, co-workers, and promotion. 5. A work itself was the most improtant facet th the dietitian followed by wage and promotion. 6. Task identity of the JCI facets was the most prevalent job characteristics followed by variety, dealing with others, feedback and friendship. 7. Three groups of dietitians had no significant difference in total job characteristics score. 8. A group of dietitians with a higher job satisfaction score had a significant higher score in job variety and job autonomy. 9. Organizational commitment mean score with dietitians was 1.88. 10. Job satisfaction score for five facets and total job satisfaction were significantly correlated with organizational commitment score.11. Job charateristics with job variety, job autonomy, feedback, task identity, friendship were positively correlated with organizational commitment.

• Journal of The Korean Association For Science Education
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• v.37 no.2
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• pp.335-346
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• 2017

In this study, we developed and examined the validity and reliability of the Test for Indicators of Positive Experiences about Science (TIPES) that measures students' positive experiences about science. We have developed TIPES through literature reviews, development of the preliminary version of TIPES, a pilot test and revisions of the preliminary version, and the test of the final version. Through literature reviews and Delpi methods, we developed the preliminary version of TIPES, which consists of five categories such as science academic emotion, science-related self-concept, science learning motivation, science-related career aspiration, and science-related attitude. Using the preliminary version, we conducted a pilot test with 198 students consisting of 4th, 6th, 8th, and 10th graders, and modified the first version based on the results from the pilot test and expert meetings. We then conducted a main test with the revised version of TIPES with 1,841 students consisting of 4th, 6th, 8th, and 10th graders. According to a confirmatory factor analysis, a reliability test and descriptive statistics analyses, TIPES found to have a good validity as well as reliability. In addition, there are statistically significant differences in the norm distribution and scores of TIPES by student's grade, gender, school location, and level of participation in science-related activities. Discussed in the conclusion are the implications of this research for science education research and science teaching and learning practices in the school.

• Journal of The Korean Association For Science Education
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• v.18 no.2
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• pp.149-160
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• 1998

The purpose of this study was to analyze the 6th national secondary science curriculum and classroom practices to collect the basic data for developing secondary science program focusing on creative problem-solving ability. The creative problem-solving ability was conceptualized as an active process of producing new solutions to problems and consisted of five components: general knowledge, domain-specific knowledge, motivation, divergent thinking and critical thinking. The research questions were generated as follows: (1) Whether creative problem-solving elements-domain specific knowledge(declarative knowledge and inquiry methods) were included or not in the 6th secondary science curriculum, textbooks and teacher's guide? If so, how are they represented? (2) Whether the teachers tried to enhance divergent and critical thinking of their students. Through content analyses, observations and interviews, these research questions were answered as follows: (1) Inquiry methods, which are important to develop creative problem-solving abilities in science, were underestimated in comparison with declarative knowledge. In other words. inquiry methods were regarded only as tools to understand the scientific concepts and principles. (2) It was hard to find the situations which teachers provided opportunities for divergent and critical thinking to their students. Based on these results, the followings were recommended: (1) Inquiry methods should be regarded as a goal not as a tool and be used to acquire inquiry methods themselves. (2) Teachers should not stick to the prescribed inquiry methods prescribed in the textbook, but to give opportunities for thinking various kinds of inquiry methods to improve divergent and critical thinking.

• KIISE Transactions on Computing Practices
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• v.21 no.2
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• pp.101-108
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• 2015

This paper presents the implementation of a system that recommends empirical best routes based on classification of large trajectory data. As many location-based services are used, we expect the amount of location and trajectory data to become big data. Then, we believe we can extract the best empirical routes from the large trajectory repositories. Large trajectory data is clustered into similar route groups using Hadoop MapReduce framework. Clustered route groups are stored and managed by a DBMS, and thus it supports rapid response to the end-users' request. We aim to find the best routes based on collected real data, not the ideal shortest path on maps. We have implemented 1) an Android application that collects trajectories from users, 2) Apache Hadoop MapReduce program that can cluster large trajectory data, 3) a service application to query start-destination from a web server and to display the recommended routes on mobile phones. We validated our approach using real data we collected for five days and have compared the results with commercial navigation systems. Experimental results show that the empirical best route is better than routes recommended by commercial navigation systems.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6C
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• pp.259-266
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• 2011

Conducting statistical analysis of foundation resistance using sufficient number of well-performed load test results is prerequisite for the calibration of reliable resistance factors for foundation LRFD. In this study, a rational analysis method is proposed so that the proof pile load test results can be reflected in update of resistance statistical characteristics based on Bayesian theory. Then, resistance factors for driven steel pipe piles compatible with Korea foundation practices are updated by implementing this rational analysis method. To accomplish the resistance factor updates, (1) prior pile resistance distribution is constructed based on the results of pile load tests, which loads are imposed at least up to their ultimate limit loads. (2) likelihood function is obtained from the results of proof pile load tests, and (3) posterior pile resistance distribution is updated by combining these prior pile resistance distribution and likelihood function. The resistance factors are updated using the posterior pile resistance following the first-order reliability method (FORM). From the possible results of five consecutive proof pile load tests, the updated resistance factors vary within ranges of 0.27-0.96 and 0.19-0.68 for target reliability indices of 2.33 and 3.0, respectively. Consequently, it was found that the Bayesian theory-implemented method enables the updates of resistance factors in an efficient way when reliable resistance factors are not available due to the lack of well-performed pile load test results.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.147-158
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• 2016

Objectives: The objective of this study was to evaluate the assessment of exposure to welding fume and heavy metals among construction welders. Methods: Activity-specific personal air samplings(n=206) were carried out at construction sites of three apartment, two office buildings, and two plant buildings using PVC(poly vinyl chloride) filters with personal air samplers. The concentration of fumes and heavy metals were evaluated for five different types of construction welding jobs: general building pipefitter, chemical plant pipefitter, boiler maker, ironworker, metal finishing welder. Results: The concentration of welding fumes was highest among general building pipefitters($4.753mg/m^3$) followed by ironworkers($3.765mg/m^3$), boilermakers($1.384mg/m^3$), metal finishing welders($0.783mg/m^3$), chemical pipefitters($0.710mg/m^3$). Among the different types of welding methods, the concentration of welding fumes was highest with the $CO_2$ welding method($2.08mg/m^3$) followed by SMAW(shield metal arc welding, $1.54mg/m^3$) and TIG(tungsten inert gas, $0.70mg/m^3$). Among the different types of workplace, the concentration of welding fumes was highest in underground workplaces($1.97mg/m^3$) followed by outdoor($0.93mg/m^3$) and indoor(wall opening as $0.87mg/m^3$). Specifically comparing the workplaces of general building welders, the concentration of welding fumes was highest in underground workplaces($7.75mg/m^3$) followed by indoor(wall opening as $2.15mg/m^3$). Conclusions: It was found that construction welders experience a risk of expose to welding hazards at a level exceeding the exposure limits. In particular, for high-risk welding jobs such as general building pipefitters and ironworkers, underground welding work and $CO_2$ welding operations require special occupational health management regarding the use of air supply and exhaust equipment and special safety and health education and fume mask are necessary. In addition, there is a need to establish construction work monitoring systems, health planning and management practices.

• Journal of Agricultural Extension & Community Development
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• v.21 no.1
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• pp.219-244
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• 2014

Agricultural extension service in Ethiopia was started in early 1950s with mandate of transferring local research outputs and technologies to farmers, and importing technologies and improved practices from abroad. Extension service provided in this early time was limited to areas surrounding the experiment stations. Since then, Ethiopian Agricultural extension service has passed through at least five stages: the land grant extension system, the Comprehensive Package Programs, the Minimum Package Projects, the Peasant Agricultural Development Program, and the Participatory Demonstration and Training Extension System (PADETS). The comprehensive package extension program was initially implemented in selected pilot areas and eventually to be scaled up to cover about 90% of the farming community within 15-20 years time. The program used demonstration plots managed by development agents and used to train farmers organized through various field days. However, since all of these programs were operational in only small areas, the vast majority of the country was out of their reach. Through Participatory Demonstration and Training Extension System, the extension service in Ethiopia has come under the spotlight and government debates and external reviews are putting additional scrutiny on the system. Despite this long history, the system is still in its infancy in terms of coverage, communication and institutional pluralism. Currently in Ethiopia the Agricultural extension is provided primarily by the public sector, operating in a decentralized manner through which extension is implemented at the district level. Therefore, the main focus of this paper is to scrutinize the past, the present and the future Agricultural extension system in Ethiopia.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.907-916
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• 2015

The purpose of this study was to identify characteristics of vegetation structure, vegetation succession, and species diversity of artificially planted Chamaecyparis obtusa (CO) stands. The study was carried out by performing vegetation survey for eight CO stands located in Jeollanam-do Province, Korea. Analysis on vegetation classification and ordinations of the stands was conducted using the data from the vegetation survey, and as a result, the stands were classified into five types of communities. Community I showed a considerably lower index of species diversity when compared to other communities because the canopy of the dominant CO was so highly dense that the low-height vegetation was not able to develop or the low-height vegetation almost disappeared due to elimination of weed trees. Meanwhile, the Community II - IV had relatively higher indices of species diversity because various native tree species mixed with the low-height vegetation and competed with each other in the understory and shrub layers to some degree of stability or in their early stage of vegetation development. Community V, lastly, showed higher use intensity as a recreational forest, thus developing simpler vegetation structure on account of artificial intervention. There was positive correlation between photosynthetically active radiation entering the forest floor, number of observed species and index of species diversity. Such characteristics of vegetation structure in CO stands are closely associated with forest management and prescription for planting reforestation, thinning, and brush cutting in the past. There was a slight difference in vegetation structure and species diversity by communities, based on rotation time of the vegetational succession, process of disturbance frequency and disturbance, development, and maturity by planting CO stands. However, when compared to natural forests, the CO stands showed simpler vegetation structure. Because artificial forests are vulnerable in ecosystem service with lower species diversity, a drive for ecological management is needed for such forests to change into healthy ecosystems that can display functions of public benefit.

• Journal of the Korean earth science society
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• v.23 no.4
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• pp.309-323
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• 2002

This qualitative study investigated preservice teachers' understandings of the ontology and epistemology underlying constructivist notions of learning through four in-depth interviews. Of the sixteen participants in a larger study, five significantly changed ontological and epistemological beliefs and eleven did not. This study focused on these eleven teachers who have hardly changed their philosophical beliefs throughout the teacher education program. Ten teachers who consistently maintained the scientific realist beliefs were presented as a composite case (Young's case). Among the eleven teachers, there was one outlier who had consistently maintained an idealist and relativist epistemological position from the beginning of the study and was subjected to another case analysis (Ben's case). These cases corroborated the assertion that each individual's deeply entrenched ontological and epistemological beliefs are very hard to change. For researchers, this study offers insights into the reasons that preservice teachers give for non-changes in their thinking about learning to teach. The study also examines preservice teachers' perceived constraints in implementing their ideal pedagogies and the influence of the teacher education program on their pedagogical beliefs changes. The benefits and influences of the M.Ed. program's theoretical coursework and the field experiences on these teachers' learning-to-teach experiences are addressed with rich data. The implications for teacher educators as well as for the instructional practices of preservice teacher education programs are discussed. This research emphasize necessity of the field-based teacher education program and the need of empowering experienced school teachers as teacher educators in teacher preparation and professional development.