• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.39-44
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• 2016

Recently, there has been increasing concern regarding the collapse of hydraulic structures due to abnormal climate conditions. Therefore, numerous studies of the collapse of hydraulic structures have been carried out. In particular, the velocity of the propagation of a flood wave-front is important for predicting the inundation safety and establishing an EAP (Emergency Action Plan). Although many hydraulic tests have been conducted for precise predictions of a flood wave-front, the scale effect from downsizing has not considered. In this study, the relationships between surface tension and the concentration of surfactant, between surface tension and the velocity of flood wave propagation, and between surface tension and the Weber Number were derived through hydraulic tests using a surfactant and image analysis equipment. Based on these relations, the modification factor for the scale effect of the front of flood wave propagation was suggested. The results highlight the necessity of a modification factor when the Weber Number is lower than 12.2, but the scale effect can be ignored when the Weber Number over 12.2.

• Proceedings of the Korean Vacuum Society Conference
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• 2001.02a
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• pp.218-218
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• 2001

• Korean Journal of Oriental Medicine
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• v.16 no.2
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• pp.159-166
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• 2010

Objective : The purpose of this study is to compare the Effect of Acupuncture on Local Acupoints and Distal Acupoints for Patients with Whiplash Injury. Method : From January 1st 2009 to September 31th 2009, 10 patient were divided into 2 groups. One group was taken Local Acupoints, and the other group was taken Distal Acupoints. To check pain and treatment satisfaction, visual analog scale(VAS) and five-point likert scale were used before and after treatment. Result : Both acupuncture theraphy showed improvement in VAS and five-point likert scale. And Local Acupoints group showed more effective than Distal Acupoints group on five-point likert scale. Conclusion : This Study suggests that Acupuncture on Local Acupoints and Distal Acupoints can be applicable to improve symptom in Patients with Whiplash Injury.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.7
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• pp.1065-1074
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• 2008

The purpose of this paper was to present the proximity of clothing to self(PCS) which is a subjective measure developed by Sontag and Lee(2004). PCS is the scale to examine the relationship between self and clothing. Since PCS scale was prepared for American consumers, it is necessary to verify the validity as a measure to Korean consumers. Consumers' quality of life are functionally related to satisfaction with all of life's domain and subdomains. Clothing in life facilitates the creativity and expressiveness to the wearer, especially to adolescent. The concept of bottom-up spillover effect developed by Lee et al.(2002) was adopted as research model. Data were gathered by surveying university students using convenient sampling, 419 questionnaires were used in the statistical analysis. It was proved that PCS scale was effective measure to Korean consumers. And also PCS scale could be a proxy indicator in view of the fact that clothing was deeply related to consumers' quality of life.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.94-103
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• 2008

This study measured technology transfer efficiency for public institutes. The study made use of DEA being one of the non-parametric linear programming to evaluate technology transfer efficiency for public institutes and to measure technology efficiency, pure technical efficiency and scale efficiency. The measurement of the technology transfer efficiency for public institutes was as follows: The cause of the technology transfer inefficiency was affected by pure technical inefficiency more than by scale inefficiency. Public institutes' RTS(Return To Scale) value varied depending upon the features of the organizations than the features of the regions. Public research institutes' RTS value is more effective than universities' RTS value. We compared the RTS group with the RTS of Projected DMU groups. The RTS group had constant returns to scale effect while the RTS of the Projected DMU had increasing returns to scale effect. The technology transfer efficiency of public institutes varied depending upon the features of the organizations and regions : The technology transfer efficiency of public institutes were as follows : public research institutes at the metropolitan area, public research institutes at the local areas, universities at the metropolitan area and universities at the local areas. In other words, the technology transfer efficiency was affected by organizational characteristics more than by regional characteristics at the place where public institutes were located.

• Korean Journal of Metals and Materials
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• v.48 no.8
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• pp.749-756
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• 2010

Low carbon steels were oxidized isothermally at 1050 and $1180^{\circ}C$ for 4 hr in air in order to determine the effect of alloying elements Si, S, Cu, Sn, and Ni on oxidation. For oxidation resistance of low carbon steels, the beneficial elements were Si, Cu, and Ni, whereas the harmful elements were S and Sn. The most active alloying element, Si, was scattered inside the oxide scale, at the scale-alloy interface, and as an internal oxide precipitate. The relatively noble elements such as Cu and Ni tended to weakly segregate at the scale-alloy interface. Sulfur and Sn were weakly, uniformly distributed inside the oxide scale. Excessively thick, non-adherent scales containing interconnected pores formed at $1180^{\circ}C$.

• International Journal of Railway
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• v.4 no.2
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• pp.50-55
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• 2011

The dynamic stability of railway vehicle has long been one of the important issues in railway safety. The dynamic simulator has been used as a tool for investigating the dynamic stability of railway vehicles and wheel/rail interfaces. In particular, small scale simulators have been widely used in laboratory studies instead of full scale roller rigs which can be quite costly and rather inconvenient for testing out the effect of diverse design parameters. But techniques for design of a small scale simulator for the fundamental study about the dynamic characteristics of the wheel-rail systems and the bogie systems have not been well developed in Korea. Therefore, a research on the development of a small scale simulator for investigating bogie dynamics needs to be undertaken. The present paper investigates design of a small-scaled derailment simulator and the design of a small scale bogie. The simulator developed can be used to investigate the effect of diverse parameters such as attack angle, wheelbase and cant on dynamic behavior of the bogie and key dynamic performance parameters such as derailment coefficient and critical speed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.1
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• pp.12-21
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• 2010

This paper focuses on the hover performance experiment of a small-scale single rotor in partial ground conditions. In this study, small-scale rotor blade rotating device and floor panel are used to include partial ground effect. Thrust and torque were measured with varying collective pitch angles at fixed rotor rotating speed. The overlap distance between rotor and ground is d, the rotor diameter is D. It was shown that the ground effects have little effect on the rotor performance until d/D is 0.25. Four blade rotor has more increased thrust and more reduced power than those of two blade rotor because of stronger ground effect. In addition, it was also found that the thrust increases as a collective pitch angle become smaller. Based on these experiment results, we deduced new empirical equation considered blade number and partial ground effect.

• The Journal of the Korea Contents Association
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• v.18 no.12
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• pp.185-196
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• 2018

Current study was conducted to examine the mediating effect of maladaptive cognitive emotion regulation strategies and negative affect on the relationship between perceived stress and smartphone addiction of adults and to explore suggestions for counseling adults with smartphone addiction symptoms. Three hundred adults(146 males, 154 females) were administered perceived stress scale, maladaptive cognitive emotion regulation strategy scale, negative affect scale, and smartphone addiction scale. The main results are summarized as follows: First, perceived stress had positive influence on smartphone addiction. Second, negative affect showed mediating effect on the relationship between perceived stress and smartphone addiction. Third, maladaptive cognitive emotion regulation strategies did not show mediating effect on the relationship between perceived stress and smartphone addiction. Forth, maladaptive cognitive emotion regulation strategies and negative affect showed double mediating effect on the relationship between perceived stress and smartphone addiction. Based on the above results, it was suggested to include stress management and relief of negative affect through modification of maladaptive cognitive emotion regulation strategies in the treatment program for adults at high risk of smartphone addiction.

• Proceedings of the Korean Vacuum Society Conference
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• 2001.02a
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• pp.214-214
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• 2001