• Proceedings of the ESK Conference
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• 1998.04a
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• pp.124-130
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• 1998

본 연구의 목적은 트레드밀 운동시 신체에 가해지는 중량별 부하가 심박수, 환기량, 호흡수, 이산화탄 소배출량, 산소섭취량, 체중당산소섭취량, 호흡교환률 등에 어떠한 영향을 미치는 지를 측정하여 훈련이 나 운동처방에 도움이 될 수 있는 자료를 얻고자 하였다. 피검자들은 성인 남녀 각 5명씩을 대상으로 하였으며, 신체 중량별 부하는 남자에게 안정시, 무부하, 5kg부하, 10kg부하, 15kg무하로 하였으며, 여자 에게는 안정시, 무부하, 5kg부하, 10kg부하로 구분하여 측정하였다. 운동부하는 트레드밀(TC-1200, Technogym, Italy)을 이용하여 중량별로 4km/hr로 3분간 실시하였다. 단계별 운동부하에 의한 인체에 미치는 호흡순환계의 변화를 조사하기 위해 호흡순환계의 변인을 측정 분석한 결과, 다음과 같은 결론 을 얻었다. 남자그룹의 경우는 심박수, 환기량, 이산화탄소배출량, 산소섭취량, 체중당산소섭취량, 호흡 교환률에 대한 중량별 평균차의 검증에서 안정시와 무부하, 5kg부하와 10kg부하, 10kg부하와 15kg부하 사이 에는 유의한 차이가 나타났고, 무부하와 5kg부하 사이에서는 유의한 차이가 없었다. 호흡수에있어서는 10kg 부하와 15kg부하 사이에서만 유의한 변화가 나타났다. 여자그룹의 경우는 심박수, 환기량, 이산화탄소배출 량에 대한 중량별 평균차의 검증에서는 안정시와 무부하, 무부하와 5kg부하, 5kg부하와 10kg부하 사이에서 유의한 변화가 나타났으며, 산소섭취량과 제중당산소섭취량에 있어서는 안정시와 무부하, 무부하와 5kg부하 사이네서만 유의한 변화가 나타났다. 또한 호흡교환률과 호흡수에 있어서는 안정시와 무부하 사이에서만 유의한 변화가 나타났으며, 무부하와 5kg부하, 5kg부하와 10kg부하 사이에는 유의한 차이가 없었다. 이와 같은 결과를 종합해 보면 남자에게는 걷기시에 단계별 무게부하가 호흡순환계에 영향을 미친다고 볼 수 있 으나, 5kg까지의 부하는 호흡순환계에 영향을 미치지 않고 일을 수행할 수 있음을 알 수 있다. 그리고 여자에게는 걷기시에 단계별 무게부하가 운동시 심박수와 환기량, 이산화탄소 배출량에는 영향을 미치고 호흡 교환률과 호흡수에는 영향을 미치지 않음으로보아, 여자에게는 걷기시에 단계별 무게 부하가 호흡순환계에 영향을 받고있음을 알 수 있다.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.61-67
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• 2018

This study was conducted to ascertain the mediating effects of aggression in high school students' relationship with smartphone overuse and cyberbullying. Data were collected from 328 high school students in K city using self-report questionnaire. The collected data were analyzed using SPSS 22.0 and AMOS 22.0. The results show that cyberbullying has a positive correlation with smatrphone overuse(r=.321, p<.001) and aggression(r=.397, p<.001). Smartphone overuse had a direct effect on aggression(${\beta}=.195$, p=.014) and aggression had a direct effect on cyberbullying(${\beta}=.260$, p=.007). In addition, the mediation effects of aggression on the relationship between smartphone overuse and cyberbullying were confirmed(${\beta}=.051$, p=.007). In order to reduce cyberbullying in high school students, it will be necessary to develop cyber ethical awareness education programs to reduce aggression as well as regulations on excessive use of smartphones.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.304-310
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• 1986

A. calcoaceticus C10 grown on cyclohexanol as sole source of carbon and energy produced cyclohexanol dehydrogenase(CDH) and glucose dehydrogenase (GDH) concomitantly. CDH and GDH were different in coenzyme, induction and electrophoretic patterns. CDH depended for activity on $NAD^+$ only, while GDH required $NAD^+$ or $NADP^+$ alternatively. CDH was produced in the medium added cyclohexanol, but GDH was produced in various media such as LB, LB added 0.2% glucose or cyclohexanol and cyclohexanol medium. Productivity of CDH in A. calcoaceticus C10 was enhanced about 8 times by the addition of 0.2% cyclohexanol to LB medium after 4 hours as much as LB medium only. Production of CDH was induced by cyclohexanol, cyclohexanone, cyclohexan-1,2-diol and cyclohexene oxide, but not induced by ${\varepsilon}-caprolactone$ and adipate.

• The Journal of Korean Association of Computer Education
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• v.19 no.1
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• pp.63-76
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• 2016

The damage of cyber bullying is increasing. A response of code is needed with that of law and education. This study would use the strengths of a virtual simulation as one of the technical solutions. Students learn cyber bullying and prevention of it through each step. The steps in this application model consist of recognition${\rightarrow}$judgement${\rightarrow}$decision${\rightarrow}$behavior. Each detailed step of this model is made of pre-briefing${\rightarrow}$demanding of response${\rightarrow}$participating in response${\rightarrow}$result and feedback${\rightarrow}$growth${\rightarrow}$debriefing. Thus we developed the application model of this virtual simulation and implemented it for education and prevention of cyber bullying. We hope that the model and simulation developed by this study would reduce the damage resulting from cyber bullying.

• Journal of the Korean Geotechnical Society
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• v.30 no.3
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• pp.5-16
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• 2014

Soil-nailing has two main resistance factors: skin friction between ground and grouting; and tension load of reinforced material. These two factors will affect the load-displacement curve when performing soil-nailing pullout tests. The purpose of this paper is to figure out the shear behavior between ground and soil-nailing focusing on the net load-displacement behavior during soil-nailing pullout tests. Firstly, the net load-displacement curve between ground and grouting is estimated theoretically. Then, in-situ pullout load tests are performed on various ground conditions to obtain the load-displacement curve occuring between ground and grouting. Since the measured shear displacement includes elongation of the reinforced material (steel nails), the net load-displacement curve can be obtained by subtracting the elongation magnitude of steels from the measured displacement. It was found that the measured net load-displacement curve matches reasonably well with the theoretically estimated curve.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.1
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• pp.77-82
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• 2013

A cyclone separator has been widely used in various industrial processes for removing fine particulate matter because it is easy to fabricate, cost effective, and adaptable to extremely harsh conditions. However, owing to the complex flow field in cyclones, a complete understanding of the detailed mechanisms of particulate removal has not yet been gained. In this study, a theoretical analysis was performed for calculating the collection efficiency and cut-off size in cyclones by taking into account the effects of geometrical and flow parameters. The collection efficiency and cut-off size values predicted by the theoretical model showed good agreement with experimental measurements for particles with a diameter of $0.5-30{\mu}m$. It was also revealed that the surface friction, along with the flow and geometrical parameters, has a significant effect on the cyclone performance.

• The Journal of the Korea Contents Association
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• v.17 no.5
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• pp.18-33
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• 2017

The purpose of this study was to examine the effect sizes of personal, family, peer, school, cyber environment, experience of bullying/victimization factors on cyberbullying perpetrating behavior among students in Korea using meta-analysis. Published academic journals and master/doctoral dissertations from 2010.01.01 to 2016.10.31 were identified using Research Information Sharing Service(RISS) data base. Keywords for search were cyberbullying, cyber-exclusion, cyber-violence, cyber-harassment, online/SNS peer harassment. A total of 43 studies were selected for meta-analysis. Personal factors and experience of bullying/victimization showed moderate effect sizes(0.28~0.29) and peer, family, cyber environment, school domains showed small effect sizes(0.08~0.13). Results of the study may be used to guide effective prevention or intervention strategies against cyberbullying among adolescents.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.185-196
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• 2021

This study is based on the 'National Pilot Project on Digital Signage in Sejong Special City', one of the pilot projects initiated by the Ministry of Public Administration and Security. This project was an attempt to present the digital signage as a 'public service content platform' integrated with smart technologies. This study suggests that the planning strategy for placing public service contents on digital signage platform should focus on interests of local communities or users rather than high-tech suppliers of digital signage. In consideration of growing needs for smart technology-based public service, this study concentrates on the strategy for developing 'public digital signage services'. In addition, 'digital signage service tools' were designed to easily establish or execute the strategy. The aim of this study is developing the strategy to make digital signage a public cultural service platform as well as a digital advertisement tool. The final goal of this study is to demonstrate public value creation performance of the 'Revitalisation Project of Sejong City's Commercial Districts', which was possible thanks to the proactive involvement of citizens coupled with progressive utilization of interactive media.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.576-585
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• 2021

This study was a descriptive research study to examine the factors influencing cyberbullying tendency among college students. The data used in this study were collected from July 31 to August 13, 2020, from 396 students attending universities across South Korea. The collected data were analyzed using frequency, percentage, mean, standard deviation, Pearson correlation coefficients, PROCESS macro model 4, Bootstrap, Sobel test using IBM SPSS Statistics version 20.0 and PROCESS macro for SPSS. The results of this study are as follows. First, there was a significantly negative correlation between academic stress and self-control (r=-.246, p<.001). There was also a positive correlation between academic stress and cyberbullying tendency, but it was not significant (r=.096, p=.055). Second, the mediation effect of self-control is significant between academic stress and cyberbullying tendency (R2=.039, p<.001). Therefore, Academic stress and self-control should be considered in the development of cyberbullying prevention programs, and further research is also needed to verify the effectiveness of the cyberbullying prevention program based on this study.

• Journal of Practical Agriculture & Fisheries Research
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• v.19 no.1
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• pp.61-73
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• 2017

This study aimed to determine the effect of organic matter content and water condition in soil on yield and sugar content of two varieties of Helianthus tuberosus. The plants were grown with high and low organic soil either under irrigation or no irrigation. In result, the yield of Helianthus tuberosus was higher about 7kg in soil with high organic matter than in soil with low organic matter, while it was higher about 11kg under the irrigation than under no irrigation. The yield of white variety was higher about 9kg than that of purple variety. Under the irrigation, a 12kg and 9kg of higher yields were observed in the soil with high and low organic matter content, respectively, than under no irrigation.