• Journal of Powder Materials
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• v.30 no.1
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• pp.13-21
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• 2023

In additive manufacturing, the flowability of feedstock particles determines the quality of the parts that are affected by different parameters, including the chemistry and morphology of the powders and particle size distribution. In this study, the microstructures and flowabilities of gas-atomized heat-resistant alloys for additive manufacturing applications are investigated. A KHR45A alloy powder with a composition of Fe-30Cr-40Mn-1.8Nb (wt.%) is fabricated using gas atomization process. The microstructure and effect of powder chemistry and morphology on the flow behavior are investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and revolution powder analysis. The results reveal the formation of spherical particles composed of single-phase FCC dendritic structures after gas atomization. SEM observations show variations in the microstructures of the powder particles with different size distributions. Elemental distribution maps, line scans, and high-resolution XPS results indicate the presence of a Si-rich oxide accompanied by Fe, Cr, and Nb metal oxides in the outer layer of the powders. The flowability behavior is found to be induced by the particle size distribution, which can be attributed to the interparticle interactions and friction of particles with different sizes.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.98-114
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• 2017

This study analyzed the commemorative landscapes of eight Holocaust concentration camp memorials(HCCM) of Germany and Poland from a landscape architecture point of view including historical landscape, places and remains, and monuments. A site survey was conducted at Dahau concentration camp memorial(CCM) and Bergen-Belsen CCM of Germany in September of 2015 and the Auschwitz-Birkenau extermination camp memorial(ECM), Majdanek ECM, Belzec ECM, Sobibor ECM, Treblinka ECM, Chelmno ECM of Poland in April of 2016. The results are as follows. First, the landscape of the concentration camp at Dahau CCM, Auschwitz ECM, and Majdanek ECM liberated by the Allied Forces was well conserved with the maintenance of camp facilities and the spatial structure of camps while monuments and memorials seized by sociopolitical argument were built with restriction. But Belzec ECM, Sobibor ECM, Treblinka ECM, and Chelmno ECM devastated and planted artificially to forest were overwhelmingly surrounded with natural landscape, and also, excavated relics and remains were preserved and the monuments were built at the place of memory. Second, gas chambers, crematoriums, guard posts, electric wire fences, railroads and ramps, barracks, and drainage ditches were considered to be typical facilities present in the camp structure and the gas chambers, crematoriums, human ashes, and mass graves demonstrated the horrible history of these camps and the railroad and ramp where Jewish prisoners arrived also had the strong sense of place. These remains were regarded as symbolic elements to create a memory of the tragedy and place. Third, commemoration of victims was applied as the basic concept and recalling the memory of the Holocaust was also considered very important content. Religious reconciliation and peace was represented at Dahau CCM and the Jewish identity was strongly expressed at Treblinka ECM and Belzec ECM representing the Jewish community and Judaism. Fourth, the monuments with semi-abstract styles and abstract sculptures represented the Holocaust symbolically and narratively and came into the conflict caused by the abstractness to the memorial landscape at Auschwitz-Birkenau ECM and Bergen-Belsen CCM. Fifth, remains for recalling the memory of tragedy and place and symbolic monuments to stand for public memory were juxtaposed at the same place and preserving on the authenticity of camp site had been conflicted with monumentalizing intentionally. Further study will required a concrete investigation of the monuments in the HCCM and an attempt to comparatively study the commemoration characteristics of memorials in Korea.

• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.19-26
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• 1994

An in uipo culturing to examine the cyst stage of ToxopLQsma gondii (ME49 strain) was Investigated using murine peritoneal macrophages, and we also examined the effect of CAMP or DHFR Inhibitors on the growth of bradyzoltes. For experiments ICR mice were Injected 1.p. with 1,500 brain cysts. At 1, 3, 5 and 7 days, peritoneal exudates were Isolated and then adherent peritoneal macrophages were cultured for 1,3,5 and 10 days. Growth pattern of bradyzoltes was measured by (3H)-uracil uptake assay and morphological pattern of pseudocysts formed in macrophages was observed Uth Glemsa stain. Mostly bradyzoites were observed In the macrophages extracted at 3 and S days post Infection. After 3 days in vitro, a number of pseudocysts were formed in the macrophages and the size of pseudocysts was increased during further 5 and 10 days in vitro culture. CAMP stimulated the growth of bradyzoltes when in uiuo 3 and 5 days and then in vitro 5 and 10 days conditions were applied. In case of.DHFR Inhibitors, pynmethamlne produced a linearly decremental effect with a cont.-dependent mode but methotrexate was not effective against Intracellular bradyzoltes or pseudocysts In this system. It was suggested that cyst-forming strain of T gondii (ME49 strain) could be maintained and cultivated in uitro by use of murine peritoneal macrophages. In uivo 3 and 5 days and then in uiko 5 and 10 days conditions appeared to be suitable for culturing of bradyzoltes. CAMP and pyrimethamine had an effect of stimulation and inhibition on the growth of bradyzolte, respectively.

• The Journal of the Korea Contents Association
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• v.17 no.4
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• pp.72-82
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• 2017

The purpose of this paper was to explore university students' perceptions on NEST(Native English-speaking Teacher)s and NNEST(Nonnative English-speaking Teacher)s who taught in an English camp of A university. 172 university students participating in the English camp during the vacation were asked to fill out a questionnaire including the satisfaction with the camp, NESTs' and NNESTs' general teaching qualifications, class management, and teaching contents. The data were analyzed through frequency, Pearson's Chi-square test and Fisher exact test. The research found that students were satisfied with NESTs' and NNESTs' classes in the camp. The students recognized that NESTs offered interesting classes while NNESTs prepared and taught the classes well. They also pointed out that NESTs instantly managed classes while NNESTs tended to rely on textbooks and offered more materials in classes. They realized that NNESTs focused more on English speaking, gave students more feedbacks about students' outcomes, and communicated with students more effectively. The paper provides pedagogical implications for more effective NESTs' and NNESTs' teaching.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.9-20
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• 2017

Camp Page, which has been located in front of Chuncheon Station for about 50 years since 1958, recently opened to the public. Chuncheon City is currently struggling to construct a park on this site due to an uncertainty of general plans and financial difficulties. Accordingly, this research conducted a cognitive survey about site usage with Camp Page users in order to clarify directions for efficient establishment of parks within the former military base. The course of research includes analytical methods such as a survey targeting Chuncheon citizens and tourists both in the field and online, a frequency analysis of 1,360 index samples, a cross analysis and t-test. As a result, firstly, Chuncheon citizens recognized the image of Chuncheon as a city with a fresh, clean lakeshore whereas tourists think of it as a city for sightseeing and leisure. Hence, it was justifiable to conclude that the city should organize various programs for people to enjoy leisure activities while at the same time protecting the environment. Second, the awareness of tourists about Camp Page was relatively low and both citizens and tourists recognize that it was not sufficient enough for enjoyment of free time. The majority answered "space for culture and art and for experiencing the natural environment" when asked about the direction of space creation at Camp Page, which indicates that the site will need to be available both for cultural art and nature experiences. Lastly, it was thought that the direction of developing leisure facilities in Chuncheon city should include the improvement of worn out installations and developing chain products among programs. This research will be able to use fundamental data for the efficient utilization of the returned U.S. military camps that are constantly merging.

• The Journal of the Korea Contents Association
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• v.20 no.3
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• pp.491-505
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• 2020

The purpose of this study is to develop an evaluation index that can assess the Army training program of Green Camp. The result of the evaluation index phased-developed with the CIPP model is summarized below. First, the literature review with documents relevant to program evaluation, Green Camp field research, and expert discussions were used to select factors considered for evaluation and develop a preliminary evaluation area and item for the four areas within the CIPP evaluation model. Second, an initial survey targeting Green Camp and soldiers in the Capital Defense Command examined the preliminary reliability·validity, and the Focused Group discussions were used to supplement the evaluation index. Third, secondary surveys were conducted in four battalions in Gangwon-do and third surveys targeted officers from twelve different corps and personnels related to the Green Camp which verified descriptive statistics analysis, exploratory factor analysis, and correlation analysis in version SPSS 24. Fourth, with the validation verification procedure, 16 evaluation area and 36 evaluation index was confirmed. Fifth, the 36 evaluation index developed was subdivided into 57 indexes and the Delphi method was applied through the policy expert to formulate 43 generalized indexes. The significance of this phased research approach was considered for the institutionalization of the usage of scientific evaluation(index) and development in policy process.

• Journal of Science Education
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• v.45 no.2
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• pp.231-246
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• 2021

The Korean Ministry of Education has emphasized the convergent ability for human resource cultivating the development of science and technology in the future. Based on this, Korean STEAM education aims to enhance students' interest and their understanding of science and technology as well as to develop students' convergence thinking and problem-solving skills. Through the camp for gifted students, students are generally introduced to produce self-directed outputs in order to solve the problem in everyday life. In this study, the author aims to find out whether the gifted high school students' creative leader competency and STEAM literacy changed after they experienced STEAM-based camp. 517 gifted students from 52 high schools in the Metropolitan city region join the camp, which is focused on generating student-centered outputs for problem-solving in daily life context. Before and after the camp, the creative leader competency and the STEAM literacy of participants were tested and compared. From the result, we found that the gifted high school students' creative leader competency and STEAM literacy improved after participating in the STEAM camp. In particular, all the sub-factors except for the social value pursuit domains in the social characteristic area of creative leader competency and the areas of creativity, respect, and communication in STEAM literacy increased. Educational implications will be discussed.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.569-570
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• 2005

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.677-688
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• 2017

The purpose of this study is to analyze the action learning lesson about the improvement process of the job support program of P university students. As a research method, we applied the related classes during the semester to the students who took courses in the course of 'Human Resource Development', which is a subject of P university, and analyzed the learner's reflection journal, interview data. As a result of the research, we went through the problem selection stage, the team construction and the team building stage. And then we searched for the root cause of the problem, clarified the problem, derived the possible solution, determined the priority and created the action plan. There are 10 solutions to the practical problems of poor job camps. Through two interviews with field experts it offered final solutions focused on promoting employment and Camp students participate in the management of post-employment into six camps. According to the first rank, job board integration, vendor selection upon student feedback, reflecting improved late questionnaire, public relations utilizing KakaoTalk, recruiting additional selection criteria, the camp provides recorded images in order. The results of this study suggest that the university's employment support program will strengthen the competitiveness of students' employment and become the basic data for the customized employment support program.

• Child Health Nursing Research
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• v.17 no.4
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• pp.207-214
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• 2011

Purpose: The purpose of the study was to identify differences in physiological· psychological environmental behavioral characteristics between obese and control children participating in a health camp and to identify the factors related to childhood obesity. Methods: Two hundred eighty seven children aged 6 to 12 years were recruited from a health camp for elementary students in D city, Korea. Data collection was done on November 28 and 29, 2009. Anthropometric measurements, blood tests, and self-report surveys were conducted. Chi-square test, independent t-test, ANCOVA, and multiple logistic regression were performed using PASW statistics 18.0. Results: Obese children had adverse conditions for both physiological and psychological characteristics. In terms of environmental and behavioral characteristics, high maternal BMI and more than two hours of TV watching were significantly associated with high risk of childhood obesity (OR=1.11, 95% CI=1.02-1.21; OR=2.05, 95% CI=1.23-3.41). Conclusion: Through a multi-factorial approach, the current study identified the differences between obese and control children participating in a health camp and risk factors of childhood obesity. These findings provide preliminary data and perspectives on intervention research for prevention and management of childhood obesity.