• Korean Journal of Construction Engineering and Management
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• v.25 no.5
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• pp.32-40
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• 2024

In the construction industry, lack of reliability in the quality of recycled aggregates, harmful substance problems, and negative consumer perceptions limit the expansion of the use of recycled aggregates. In this respect, existing studies mainly focus on the use of recycled coarse aggregates in concrete in consideration of durability. On the other hand, in the case of recycled fine aggregates, not only are there insufficient cases applied to major structures, but the scope of application is very limited due to lack of awareness. Therefore, the main purpose of this study is to present the possibility of their application in bearing and non-bearing wall structures through physical characteristics experiments of concrete bricks for masonry according to various mixing ratios of recycled fine aggregates and cement amounts. To this end, the compressive strength and absorption rate of concrete bricks were measured focusing on the mixing ratio of the recycled fine aggregate and the crushed fine aggregate and the amount of cement. As a result, it is found that it is possible to use 100% of recycled fine aggregate for 200kg/m³ of cement or 25% of crushed fine aggregate mixed with 75% of recycled fine aggregate for the same amount of cement to achieve the compressive strength of 13MPa, witch is one of the quality requirements for concrete bricks for bearing walls. In addition, it is found that to meet the strength of 8MPa, one of the quality requirements for non-bearing walls, it is sufficient to use 100% of the recycled fine aggregate for 100kg/m³ of cement. Through the absorption rate tests, it is also confirmed that the absorption rate of the concrete brick is 13% or less by meeting the required performance criteria. This means that even if recycled fine aggregate is used in the manufacture of concrete bricks, the quality standards required by KS F 4004 (concrete bricks) can be sufficiently met.

• 대한공업교육학회지
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• v.38 no.1
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• pp.221-238
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• 2013

The purpose of this study was to revise and reorganize the direction of the department of ${\bigcirc}{\bigcirc}$Industrial High School though analysis of manufacturing status and workforce demand in Chungnam province focused on the Geumsan Area. In the study, ${\bigcirc}{\bigcirc}$Industrial High School of the status and actual conditions were identified through interview, literature review and data analysis. Surveys of the school teachers, parents and students was conducted in order to investigate the awareness of renaming and reorganization of school departments, curriculum revision of the school. Statistical data was collected and analyzed in order to figure out manufacturing industry and its workforce demand of Chungnam Province in Korea. Findings of the study were as follows: Small and medium enterprises of manufacturing industry have been developed a lot in Geumsan Area in Chungnam province. Four major industries including (1) automobile parts, (2) electronic and information equipment, (3) Cutting edge culture, and (4) Agricultural-livestock and bio are intensively fostered as regional strategic industries in the Chungnam province. The manufacturing industry has a 33.6-percent, and then service-mining and manufacturing industry has a 80.0-percent of total number of employee in Geumsan Area. It is expected that industrial workforce demand of Geumsan Area come out of manufacturing and service-mining industrial sector. The following is recommended for the school curriculum revision: (1) focussing on mechanical control for the revision of computer applying mechanical department, (2) focussing on automation electric equipment for the revision of electric control department, (3) focussing on food process control for revising of bio-food industrial department. It's helpful to make a progress of the school that establish identification of industrial specialized high school as an institution of vocational education at the secondary level through supplying qualified workforce to Manufacturing industry in Chungnam Province.

• Research in Plant Disease
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• v.22 no.4
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• pp.227-235
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• 2016

Plant disease caused by root-knot nematode is a major problem in crop production. Using of chemical pesticides, one of the most efficient methods to control nematodes, have raised issues in toxicity to humans and animals and environmental pollution. In this study, to select actinomycete strains that have potential to serve as a microbial agent for control of nematodes, we investigated nematicidal activity of culture broth from 670 Streptomyces isolates. A culture filtrate of KRA15-528 isolate that was identified as S. flavogriseus on the basis of 16S rRNA sequence analysis, showed strong nematicidal activity against second stage of juveniles of Meloidogyne incognita and inhibited egg hatching; exposure to 10% of culture filtrate resulted in 71% juvenile mortality at 48 hours afters treatment and suppressed egg hatching by 54% at 9 days after treatment. When the KRA15-528 culture filtrate was partitioned with ethyl acetate and butanol, ethyl acetate layer exclusively showed strong activity; 91%, 53%, 30% of mortality at 1,000, 500, $250{\mu}g/ml$, respectively. Additionally, the culture filtrate suppressed gall formation on cucumber plant by M. incognita with no phytotoxicity. These results suggest that S. flavogriseus KRA15-528 has potential to serve as a microbial nematicide for the control of root-knot nematode disease.

• Journal of Environmental Policy
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• v.4 no.2
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• pp.31-55
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• 2005

Dangsan forests and Rural Community Forests(RCF) have been historical assets for the rural communities of more than 40,000 in Korea and they have provided an identity through the cultural heritage. The Dangsan forests and the RCF are parts of a unique cultural landscape in the rural areas as components of stream landscape. In many cases, the Dangsan forests and the RCF are located close to stream corridors. The objective of this study was to understand the function of the Dangsan forests and the RCF on stream water quality and to evaluate its ecological landscape values. Through the consideration of international concensus and domestic government policy for close-to-nature stream, we could find out that Dangsan forests and RCF's have close relationship with the close-to-nature streams. The water quality of the streams close to the Dangsan forests and the RCF are maintained with local culture. It is also compared to the streams located where Dangsan forests and the RCF are absent. Eight study sites were selected. Water samples were collected at three different locations at each study site. Water samples were analyzed for temperature, pH, total P, total N, dissolved oxygen, EC, BOD, COD and SS. Aquatic invertebrates were observed as water quality indicator species. The results showed that the number of aquatic invertebrate species, GPI, DO, EC, BOD, and SS were significantly improved in stream water due to the presence of the Dangsan forests and the RCF. The role of Dangsan forests and the RCF was evident in the conservation of stream landscape and rural culture as well as in maintaining stream water quality. The management schemes of the streams with Dangsan forests and the RCF's are also suggested.

• Journal of Service Research and Studies
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• v.14 no.1
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• pp.44-62
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• 2024

The development of online funeral services and social issues of eco-friendly funeral culture have raised awareness of the new need for online funeral culture. There have been several attempts to revitalize online funeral services in domestic institutions and companies, but the effect is weak. The purpose of this study is to propose a design that can improve the accessibility and usability of online memorial services by analyzing the usability problem factors through a First Time User Experience analysis of the online memorial platform. Therefore, in this study, in order to identify the problem factors of the online memorial platform, a literature review on the UX, OOBE, and FTUE theories was conducted. The subject of the study was the app 'Memorial'. Before analyzing the First-Time User-Experience, IA was compared and analyzed with other similar services to understand the characteristics of the UX service of the app 'Memorial', which is the subject of the study. In addition, tasks corresponding to the Unpack-Setup/Configure-First Use stage were performed on 10 subjects who had no experience using the online memorial platform. The experimental process was expressed as the UX Curve to identify factors that caused negative experiences. As a result, the major problem factors included unnecessary UI elements, the need for sensitive personal information at the membership stage, and lack of immersion in the service. The improvements included strengthening community functions to facilitate the sharing of emotions and promote smooth communication between users. We proposed UI/UX service developments that enhanced the app by incorporating these insights. In order to verify the effectiveness, serviceability, and value of the developed prototype, an interview with a expert was conducted. The interviewes consisted of three service design experts. This study was conducted to contribute to the quality improvement and activation of the recently emerging online funeral services. The study is significant as it aims to understand the current status of these services and identify the factors necessary to improve service accessibility and usability. Subsequent studies require in-depth user verification of how much the proposed improvement plan affects the actual user experience.

• Journal of dental hygiene science
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• v.13 no.1
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• pp.97-104
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• 2013

This study investigated the safety management behavior of dental professionals to minimize exposure to harmful elements of amalgam and resin. As for the use of amalgam and resin, 85.8% of them used amalgam. 100% of used composite resin 100%. 97.8% used acryl resin, and 95.7% used tray resin. 95.2% and 36.5% of them were aware of the harm of amalgam and resin respectively. When using resin, their safety management behavior score was 1.99 on average, and the lowest score was 2.50 on average for 'ventilate the indoor air when handling resin'. Their average score of the safety management behavior was 1.83 when using amalgam. The lowest score was 2.89 on average for 'use the rubber dam for patients when handling amalgam'. As a result of the safety management behavior based on general characteristics, all characteristics were significant with regard to amalgam, and my position at work and work experience were significant with regard to resin (p<0.05). The correlation between the safety management behavior and general characteristics was analyzed when dental amalgam and resin are used. Amalgam was statistically correlated with academic background (p<0.05) and position at work (p<0.05), whereas resin was statistically significantly correlated with age (p<0.05) and position at work (p<0.05). Accordingly, education about the harm of dental materials must be continuously provided for dental professionals when they handle dental materials so that safety management behavior will be conducted correctly, and active efforts to protect the health of dental professionals from harmful chemicals must be made.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.729-737
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• 2008

The purposes of this study were to investigate supporting status and subsidy for school food service and to analyze the perception of school food service officials at the educational board on using rice bread to the school food service menu. The questionnaire was developed by content analysis, situation analysis, in-depth interview and checked by the school food service officials at the educational board. The questionnaires were responded by 33 officials (respondent rate: 86.8%) during September 1 to October 26 in 2007. The major findings of this study were as follows: First, most of the respondents were women (93.9%), and worked an average of 104.36 months at school-related work. The metropolitan & provincial office of education had prevalently jurisdiction over 272.3 rural and self-operation type of elementary schools, 115.50 rural and self-operation type of middle schools and 73.0 rural and self-operation type of high schools. In the case of the district office of education, 23.3 urban and self-operation type of elementary schools, 11.6 urban and self-operation type of middle schools and 5.3 urban and contracted type of high schools were averagely managed. Second, all the respondents supported meal cost for low-income group and 50.5% provided reimbursement for organic environmental agricultural products. The highest subsidy was 16.8 billion won as meal cost for low-income group in metropolitan & provincial office and 1,050 million won as labor cost in district office. Third, the experience of performing policies for using rice was relatively lower than perception of rice bread application to school food service menu. Fourth, the advantages of using rice bread were acceleration of consuming rice (32.0%), excellence of nutrition (24.0%) and promotion of healthy image (22.7%). On the other hand, the difficulties of using rice bread were lack of facilities (72.7%), higher cost compared to wheat bread (54.5%), limitation of menu application and cooking method (15.7% each). Fifth, the opinion of utilizing rice and that of applying rice bread were significantly correlated (p<0.001). Desirability and willingness were correlated with reality for applying rice bread to the school food service menu (p<0.001). Also, comparative analysis between divided groups by perception of utilizing rice showed that willingness and experience were significantly different.

• Journal of Korean Home Economics Education Association
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• v.25 no.1
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• pp.95-118
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• 2013

The purpose of this study was to analyze the contents of housing related to characters, objectives, and contents of FCS curricular from the 1st to 2009 revised curriculum of secondary school. The data were downloaded from the NCIC homepage(http://www.ncic.re.kr/2012. 04. 08) from the 1st(1955. 08) to 2009 revised curriculum(2012. 03) of secondary school. After examining the characters and objectives of each curriculum, contents of housing was analyzed by units and context elements of middle and high school separately. The titles of the subject, the objectives, the instructions, the leaning spheres, weekly hours, grade and gender of candidates, the emphasis of the instruction, etc. have been changed through the curriculum revision. The 6th curriculum was the main period to open to both genders, the $7^{th}$ was the period to combine with technology, the 2007 version was to change the structure of contents of home economics, and the 2009 version switched technology home economics from mandatory to optional in high school. The character of the courses was presented at the 1st curriculum, but it was left out from the $2^{nd}$ to $5^{th}$ curriculum. From the $6^{th}$ curriculum, the characters were separately given to middle and high school. The character of housing area started to appear only in high school home economics from the $7^{th}$ curriculum. The course objectives were described in all curriculum of both middle and high school. This applies to housing area as well. The course objectives have been modified in order to reflect value changes due to social issues. During each curriculum, contents of housing continued to change in context, course load, and candidates. Reflection of housing trends and social needs were the main causes of the change. 2009 version emphasizes on eco-life and sense of community.

• Journal of Korean Home Economics Education Association
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• v.17 no.4 s.38
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• pp.101-115
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• 2005

The purpose of this research was to develop and applicate In based teaching$\cdot$learning process plan for Environmentally friendly Housing. The 3 main stages of process were used: analyses, planning & development, and application & evaluation. Three teaching subjects were selected to teach Environmentally friendly housing in the analysis stage. The webhard learning environment was consisted of contents and various materials such as digital video, PPT, group activity, discussion, individual and group reporting forms, and questions. The number of 101 high school students participated for the application stage during september 22-27, 2003. Most of all students evaluated very positively the various aspects of contents as well as LT cooperative learning methods md the web based learning environment. They strongly expressed to practice the practical ways of Environmentally friendly housing learned in the class in the future. The results imply that the contents and In teaching learning plan developed in this study seem to be adequate to be included in the regular text.

• Journal of Animal Environmental Science
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• v.12 no.3
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• pp.141-150
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• 2006

To optimise the efficient use of nutrients in pig slurry is to cultivate friendly environmental crops. This field survey is to investigate the actual conditions of pig slurry utilization for cultivation of crops in the agricultural farm, based on the survey for 407 selected farms in 9 provinces included 78 counties in Korea. The results obtained in this survey were summarized as follow ; The motive which came to use pig slurry in the agricultural farm were production of friendly environmental crops (29.7%), economy of chemical fertilizer (25.1%), spontaneously (19.2%), inducement of neighboring farmhouse (16.0%), increase of soil fertility (9.3%), and the others (0.7%), respectively. The proportions of pig slurry application land were 56.5% for.ice paddy, 22.6% for dry field, 13.3% for orchard, 4.4% for controlled agriculture and 3.2% for other, respectively. The number of times of pig slurry utilization per year were once (48.9%), twice (31.9%), thrice (14.0%), and the others (5.2%), respectively. The controversial points of pig slurry utilization were malodor (54.1%), insufficiency of spread equipment (22.1%), inconvenience (14.5%), over application (3.4%), over cost (2.9%), heavy metal (1.7%), sanitation (1.0%) and the other (0.2%), respectively. The results indicated that pig slurry could be used as fertilizer source of friendly environmental crops, but further studies are needed to determine the application method and value of the pig slurry for crop cultivation.