• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.5
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• pp.557-563
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• 2007

Rain-wind induced cable vibration can cause serious problems in cable-stayed bridge. External dampers attached to the cables have become widely accepted as an effective means for stay-cable vibration suppression. For very long stay-cables, however, such damper systems are rendered ineffective, as the dampers need be attached near the end of cables for aesthetic reasons. A recent study by the authors proposed that a movable anchorage system is replaced direct fixed support of the cable with a support through a bearing and damper. This paper extends the previous work by adding active control system to mitigate the cable vibration. The response of a cable with the proposed active control system is obtained and then compared to those of the cable with and without an external passive damper. The results show that the active control system can provide superior protection than the passive control system for a cable vibration.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.88-94
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• 1999

This paper describes the high efficiency inverter ballast circuit using very cheap microprocessor, which has been developed by the author. A variety of soft-switching techniques have been proposed to reduce the switching losses and EMI publems that accur with higher switching frequencies in switched inverter ballast 1be inverter ballast circuit, which employs a temperature sensing circuits has been also proposed to improve starting performance of the fluorescent lamps. That is, the inverter ballast circuit, which employs a soft-starting circuits and soft-switching techniques to implement the power factoc correcticn and to mitigate of power-loss and iocrease a life time of the fluorescent lamps, has become an attractive performance forballasting the fluorescent lamps. In this paper, the operation and the control of the inverter ballast are described in detail and experimental results are presented. As the experimental results, when enviroment temperatture is at TEX>$-40^{\circ}C$, the inverter ballast circuit has low THD(4.8%) of the input current and large power factor(98%) of the lamp current. The proposed improved ballast circuit awears to be a good performance for ballasting fluorescent lamps. lamps.

• Applied Biological Chemistry
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• v.50 no.3
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• pp.137-146
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• 2007

The substitution of fossil fuels with biofuels has been proposed by the European Union (EU) as part of a strategy to mitigate greenhouse gas emissions from road transport, increase security of energy supply and support the development of rural communities. Vegetable oils and their derivatives (especially methyl esters), commonly referred to as 'biodiesel', are prominent candidates as alternative diesel fuels. They have advanced from being purely experimental fuels to the initial stages of commercialization. They are technically competitive with or offer technical advantages compared to conventional diesel fuel. However, several problems remain including economics, combustions, some emissions, lube oil contamination, and low-temperature properties. Therefore, quality control of fuel-related properties of biodiesel is needed to obtain consistent engine performance by fuel users. The quality of the fuel is affected by the oil composition. Rapeseed oil has been targeted for fuel use because it produces an oil with a close-to-optimum set of fuel characteristics. In this paper we have reviewed past and current efforts, both by traditional seed-breeding methods and by genetic engineering, to modify rapeseed oil quality and yield.

• International Commerce and Information Review
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• v.17 no.3
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• pp.177-201
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• 2015

Korea-China FTA was initialized in 2015. Korea has a high level of dependence on trade for its economic growth, especially to China. Technical Barriers to Trade(TBT) among various non-tariff barriers is becoming increasingly important. Elimination of TBT is one of the key issues in which the South Korean government is interested since technical barriers significantly affect trade between the two countries. MRA has been considered as an effective tool to relieve such technical barriers. Several studies and surveys showed that MRA would mitigate the barriers of import and solve the problems that many companies face in international market. This study tries to seek utilization plan of MRA for Korea-China FTA. It suggests suitable utilization plan of MRA considering the difference of technical regulations between two countries. This paper has value in that it provides specific MRA strategies targeting China while other prior studies have merely analyzed the necessity of MRA.

• Journal of Korean Academy of Nursing
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• v.27 no.4
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• pp.880-891
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• 1997

The purpose of this study was (1)to undertake a survey to identify the profile of inactive nurses, who account for 42.2% of the 130,000 RN(Registered Nurses) in Korea, (2)to identify factors related to the inactivation of these nurses, (3)to identify reasons behind the high turnover rate of nurses, and (4)to delineate measures for inactive nurses to participate in professional nursing activities so as to upgrade the quality of the health care delivery system in Korea. For these purposes, this study surveyed existing literature on the turnover of nurses and, used the nominal group technique of action research, to collect ideas from hospital/nurse administrators, inactive nurses, nurses on the job, graduate students in nursing, part-time nurses, patients, and their families to formulate strategies to mobilize inactive nurses. The findings are as follows : Frist, institutional supports should be provided to mobilize inactive nurses. To be more specific : (1) A data-base needs be created at the Korean Nurses Association to link inactive nurses with jobs available. (2) Retraining programs need be established to equip inactive nurses for new jobs. (3) Comprehensive information related to employment needs should be made available. Second, a conducive environment needs to be created to draw in inactive nurses to the job market. To be more specific : (1) A system of part-time work needs to be introduced in hospitals. (2) Nurse-specialists need to be promoted. (3) Potential jobs need to be created. (4) Working environment and terms and conditions for nurses need to be improved. (5) Competent nurses need to be secured in the health care delivery system. To achieve the goals presented above, this paper presented 55 specific strategies that may help mitigate the turnover rate of nurses and, in turn, help make the Korean Nurses Association effective in implementing its policies.

• Research in Community and Public Health Nursing
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• v.19 no.3
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• pp.431-442
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• 2008

Purpose: The Purpose of this study was to examine the degree of obesity stress and analyze factors having an effect on obesity stress among college women. Method: The subjects were 347 female students from a university in J City. Data were collected using a self-report questionnaire for general characteristics, health-related characteristics, and current and preferred somatotype. Obesity stress was measured using 10 items developed by Cho (1996) based on Body Attitudes questionnaire (BAQ) of Ben-Tovim and Walker (1991). The survey was conducted from September 4 to September 7, 2007. Data were analyzed by t-test, ANOVA, Scheffe test, Spearman's rank correlation test, and stepwise multiple regression using SPSS 14.0. Results: The average score of obesity stress was $2.78{\pm}0.90$ out of 5.00. Stepwise multiple regression analysis showed that the major factors that affect obesity stress of female college students were perceived body shape, disagreement between current and preferred somatotype, history of weight control, body mass index (BMI), and perceived health status, and these factors explained 38.4% of obesity stress. Conclusion: Subjective judgment in the perception of or preference for body shape was the most important factor affecting obesity stress in female college students. Therefore, a plan is necessary to mitigate obesity stress and evaluate individually subjects who perceive themselves to be fat or want to be thinner than the current somatotype. And consultation and constant management are needed to help the high risk group (experience of weight control, BMI ${\geq}23kg/m^2$, not good health status).

• Journal of the Korea Convergence Society
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• v.6 no.3
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• pp.119-125
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• 2015

This study aims to verify the mechanism of mediated effects for protective factor among the relations of risk factor, protective factor and psychology adaptation under risky situation as functionally deficient family, and to identify the protective factors that protects adolescents with high psychology adaptation level. To achieve these goals, descriptive statistic analysis, regression analysis and logistic-regression analysis were conducted using the 5th year data of the Korea Youth Panel Study (Junior high panel) surveyed in 2008 by National Youth Policy Institute. The study results first shows that the psychology adaptation level of adolescents who experienced functionally deficient family varies depending their self-esteem and attachment to school friends. Second, it was found that there are mediated effects in the impacts of functionally deficient family on psychology adaptation. Therefore, in social work field, it is advisable to focus on the process to mitigate the risk factors or to strengthen protective factors rather than focus on the risk factors of adolescents. With this method, the negative perception of adolescents exposed to risk factors can be changed as well as the way of intervention for supporting them.

• Journal of Ocean Engineering and Technology
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• v.28 no.4
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• pp.294-305
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• 2014

In offshore structures, fire is one of the most important hazardous events. The concern of fires has recently been reflected in the rules and quantified risk assessment based design practice. Within the framework of quantified risk assessment and the management of offshore installations, therefore, more refined computations of the consequences or hazardous action effects due to fire are required. To mitigate fire risk, passive fire protection(PFP) is widely used on offshore structures. This study presents methods for a nonlinear structural response analysis considering the PFP effects under fires. It is found that a structural response analysis is most likely to use valuable technology for the optimization and design of offshore structures with PFP. Thermal and structural response analyses have been performed using LS-DYNA and FAHTS/USFOS. The results of these structural response analyses are compared with each other.

• Journal of Korea Game Society
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• v.15 no.6
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• pp.141-148
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• 2015

Most current games are composed of simple operations without a user's actual movements. because they are made up of only virtual space. For that reason, many side effects arise on a user's body and mind. The Alternative Reality Game(ARG) is new game genre that has an effect to mitigate side effects caused by activity on a virtual space. This new kind of game genre can be instrumental role in creating a greater social intimacy and a higher tendency to cooperate that potentially reaches beyond the game context. In this paper, we suggest a real implementation of ARG using mobile devices and NFC tags. In addition, a noble editor for creating an ARG and a game launcher based on mobile device are suggested.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.435-440
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• 2000

It is important to pay careful attention to construction backfill for the structural integrity of concrete box culvert. The stability of the surrounding soil is important to the structural performance of most culverts. Good compaction by the dynamic compaction roller with big capacity is as effective as good backfill materials to increase the structural integrity of culvert. However structural distress of the culvert could be occur due to the excessive earth pressure by dynamic compaction load. In this study, 16 box culverts were constructed with various compaction materials and construction methods. Three types of on-site soils such as subbase, subgrade and roadbed materials were used as backfill materials in the test program. Compaction methods were adapted based on the site conditions. In most cases, dynamic compaction rollers with 10 to 16 ton weights were used and vibration speed were applied from 2400 to 2500 rpm for the great compaction energy. Some backfill compactions with good quality soils were carried out to examine the effect of EPS(Expanded Polystyrene) panels with changes of compaction thickness. This paper presents the main results of the research conducted to access the engineering performance of the backfill materials. The characteristics of earth pressures are discussed. It is observed that subgrade and roadbed materials are needed more careful compaction than subbase materials. It is shown that EPS panels are effective to mitigate dynamic lateral earth pressure on the culverts. It is also obtained that the dynamic pressure depends on the soil properties. In addition, the coefficient of dynamic earth pressure (K$\sub$dyn/=ΔP$\sub$H/ ΔP$\sub$V/) during compaction is discussed.