• 연구논문집
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• s.28
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• pp.137-143
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• 1998

In the case of a boiler, scale is made in the tube by the chemical reactions of Ca and Mg ions contained in the water, and heat transfer rate is reduced because of increasement of heat resistance in the pipe of the heat flow. Thus it brings to reduce the energy efficiency and to make environmental pollution by the use of chemicals for the prevention and removement of scale. In this paper, we discussed the design of electronic generator for dual ultrasonic transmitters and analyzed the effect of scale prevention by ultrasound.

• Journal of Urban Science
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• v.7 no.1
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• pp.23-27
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• 2018

This research was carried out to investigate the corrosion prevention effect in the water distribution system by galvanized zinc-brass pipe which is using potential between brass and zinc. As a result of this study, pH and conductivity of influent were constant in spite of its installation, and it was difficult to estimate the effect of the installation with temporary increased and reduced concentration of Zn and Fe ions, respectively. However, since the corrosion rate of the steel coupon with galvanized zinc-brass pipe was relatively low, it has an effect of inhibiting corrosion.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.421-429
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• 2004

Purpose: This study is to evaluate the effects of drug abuse prevention program for elementary school students. Method: The design of this study is nonequivalent control group pretest-posttest design. The subjects of experimental group were 27 students and the subjects of control group were 25 students in fifth grade of elementary school in C City, Gyeongsangbuk-do. The experimental group had Drug Abuse Prevention Program, which was two days per week program, for 5 weeks. And post-test was carried out in the same way as the pre-test. Data analysis was done using frequency, percentage, mean, standard deviation, Chi-square test, t-test, Paired Samples t-test using with SPSS WIN 11.0. Result: the experimental group, to which drug abuse prevention program was given, was improved in knowledge of drug and unacceptable attitude of drug compared to the control group, but there were no significant differences of self-esteem and assertiveness between two groups. Conclusion: The drug abuse prevention program was effective to increase knowledge and attitude of drug in elementary school students.

• Korean Journal of Adult Nursing
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• v.18 no.2
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• pp.202-212
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• 2006

Purpose: This study was conducted to investigate the effects of a school based smoking prevention program for college freshmen. Method: The nonequivalent control group, pretest-post-test design was used. Among 16 departments in a University located in S city, students in 8, randomly selected, departments received 6 sessions of smoking prevention program consisted of small group discussion led by smoking cessation leaders, video watching, and lectures from March 15 to June 9, 2004. Students in remaining 8 departments did not receive any education. Student's attitude, intention, stress, temptation, knowledge and self efficacy was measured. Result: The level of stress and smoking temptation was significantly decreased in the experimental group over that of the control group. Conclusion: It was proven that this school based smoking prevention program was effective for decreasing smoking temptation in college freshmen. In the future, more efforts should be given to college age students to prevent them becoming chronic smokers.

• Journal of Korean Society for Quality Management
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• v.34 no.4
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• pp.51-64
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• 2006

The PL (Product Liability) Law has been going into effect in Korea since July 2002. Accordingly, a company's responsibility for customers who are damaged by the defect in the product safety has been gradually strict and imposed burden on management. This paper presents suggestions as to PL prevention of diary manufacturing companies through the case research of PL prevention strategies and the prevention systems of the domestic diary manufacturing company.

• Journal of Korean Academy of Nursing
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• v.38 no.3
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• pp.372-382
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• 2008

Purpose: The purpose of this study was to develop a multidimensional suicide prevention program for Korean elders by utilizing a community network and to evaluate its effect. Methods: A non-equivalent control group pretest-posttest design was used. The subjects were recruited from two different elderly institutions located in D city and K province, Korea. Nineteen subjects in the control group received no intervention and 20 subjects in the experimental group received a multidimensional suicide prevention program. Results: There were more significant decreases in depression, suicide ideation, and increases in life satisfaction in the experimental group compared to the control group. Conclusion: According to the above results, the multidimensional suicide prevention program for Korean elders decreased stressful events like depression, and suicide ideation and increased life satisfaction through the community network. These findings suggest that this program can be used as an efficient intervention for elders in a critical situation.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.6
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• pp.85-92
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• 2018

This study was to confirm the effectiveness of crime prevention in an apartment complex environmentally designed for domestic crime prevention. The researchers surveyed 267 residents on the community, fear of crime, and crime victimization. They arrived at the following conclusions. The authorization complex received higher security satisfaction results than the unauthorized complex; residents were less afraid of crime and more active in the apartment complex community. These results differ from previous studies in that the fear of crime is not related to a crime victim experience and that the fear of crime is low when there are less households in the apartment complex. Therefore, effectiveness of crime prevention abroad should not be accepted in a domestic residential environment.

• Asia Marketing Journal
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• v.19 no.2
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• pp.25-43
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• 2017

This paper addresses the central issue of whether it is effective for a firm to discourage the purchase of its own product in order to support a social cause. The objectives of this study were: a) to examine whether a cause-related self-prevention ad would stimulate more positive evaluations compared to promotional ad, particularly when the product category is more negatively socially accepted; and 2) to determine if a negative attitude toward the product could induce a boomerang effect of a selfprevention ad. Results from three experiments revealed that socially responsible prevention campaigns against firm's own product may be more effective for the product category negatively associated with social concerns or welfare. If products are more limited in the social context, communications of product prevention are beneficial to improve the public image of the brand. However, the self-hurting approach may be inappropriate for potential customers who currently possess a strong negative attitude toward the product.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.41-42
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• 2009

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.363-370
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• 2008

The present study has been performed to investigate the effect of statistical number of droplets on the simulation of the sprinkler spray using fire field model. In order to simulate the sprinkler spray characteristics, the present study uses NIST Fire Dynamics Simulator version 5.2. A group of Lagrangian particle with similar droplet characteristics, such as diameter, velocity, temperature and so on, is represented by parcel concept to decrease the total number of droplets tracked in the simulation. The present study introduces a new parameter to represent the ratio between real number of droplets and computational parcels. The dependency of the number of parcels on the fire suppression characteristics and spray patterns is quantitatively examined for different ratio between the real number of droplets and computational parcels.