• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.04a
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• pp.276-281
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• 1995

마모씨일과 발란스디스크에서의 로마킨효과가 3600rpm에서 운전되는 14단 터빈펌프의 동특성에 미치는 영향을 고찰한 결과 다음과 같은 결론을 얻을 수 있었다. 1. 14단 터빈펌프 시제품 해석을 위한 유한요소 모델링 및 해석결과는 실험적 모드해석을 통하여 5% 이내의 오차로 검증되었다. 2. 마모링 및 밸런스 디스크의 로마킨효과를 고려하였을 때 시제품 펌프의 위험속도는 그렇지 않았을 때에 비하여 1차의 경우 약 50% 상승하나 고차의 경우는 그 영향이 미미하였다. 그런데 1차 위험속도가 운전속도와 밀접한 관련이 있으므로 설계시 로마킨효과는 반드시 고려되어야 한다. 3. 마모링 및 밸런스디스크의 설계변경에 의하여 시제품 펌프의 강성을 변화시킬 경우 위험속도가 크게 변화하는 것으로 나타났다. 이를 이용하면 펌프의 심각한 구조변경 없이도 씨일의 적절한 설계에 의하여 임펠러 깃등의 고조화성분을 포함한 유해한 진동을 회피하는 동특성 설계가 가능하다. 향후 계속 연구사업으로서 씨일의 동특성 해석코드 개발 및 Wet Test를 통하여 본 연구결과를 검증하고 그 결과를 다단 터빈 펌프의 동특성 설게에 적용하여 고압 다단 터빈 펌프의 독자적 개발에 활용코자 한다.

• Journal of the Korea Convergence Society
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• v.7 no.5
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• pp.145-153
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• 2016

The purpose of this study was using a meta-analysis to estimate effect size ACT intervention program. Using a statistical method, meta-analysis has advantages that prove intervention's amount and direction. Meta-analysis facilitates comprehensive analysis. Through the data collection, 43studies were selected and 183 effect size were calculated as analysis objects. Using a 183 effect size, the overall effect size, Effect Size of categorical Factor, meta-regression result were suggested. The overall effect size of ACT program was 0.704. In the effect area of ACT, the affective domain had the largest effect size. Next were the cognitive domain, the behavioral domain. Analysis on gender of participant, mixed group had the largest effect size. Next were the female grouop, male group. Analysis on age of participant, adult group had the largest effect size. Next were the undergraduate grouop, adolescent group. Based on the findings, implications for future study were discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1253-1258
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• 2012

In the present study, we investigated the effects of Rubus coreanus Miquel (RCM) on memory ability of senescence-accelerated mice (SAM). Prone 8 strains of SAM mice (SAMP8), which is a useful animal for investigating the mechanism of brain aging and senile dementia, were fed a diet containing 100 mg/kg body weight/day of RCM for 8 weeks. Memory ability of mice was examined by using passive avoidance test and Morris water maze test. SAMP8 mice showed remarkable memory impairment compared with senescence-resistant 1 strains of SAM (SAMR1). RCM significantly improved memory ability of SAMP8 mice. In addition, acetylcholineasterase activities decreased in the brain of SAMP8 mice treated with RCM. Taken together, these results suggest that RCM may act as an acetylcholineasterase inhibitor, thereby improving senescence-related memory impairment.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.463-473
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• 2020

This study was conducted to provide basic data to find measures to alleviate the job stress of 119 Emergency Medical Technicians by identifying the mediating effect of resilience for life care in the relationship between stress coping and job stress of 119 Emergency Medical Technicians. The data for this study were collected from October 5, 2019, to October 31, 2019. The subject was 205 119 Emergency Medical Technicians working in 119 safety centers located in G Metropolitan City. The collected data were analyzed by independent t-test, ANOVA, Scheffé test, Pearson's correlation coefficients, hierarchical multiple regression analysis, and Sobel test using the SPSS Statistics 21.0 program. As a result oh the study, The mediation effect of resilience was not statistically significant in the relationship between stress coping of seeking social support type and job stress; the mediation effect of resilience was not statistically significant in the relationship between stress coping of seeking positive thinking type and job stress. but, resilience was revealed that resilience completely mediates the relationship between problem-solving type and job stress, and partially mediates the relationship between avoidance type and job stress. The measures to reduce the job stress of 119 Emergency Medical Technicians derived from the above results are as follows. First, among the 119 Emergency Medical Technicians, problem-solving stress coping type 119 Emergency Medical Technicians need to reduce job stress through resilience improvement program. Second, avoidance stress coping type 119 Emergency Medical Technicians should take part in education programs that can reduce job stress in parallel with resilience improvement program.

• Korean Journal of Culture and Social Issue
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• v.20 no.4
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• pp.391-414
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• 2014

This driving simulation study examined the effect of driver's state driving anger(SDA) on collision avoidance(CA) and situation awareness(SA), as well as the moderating effect of driver's positive and negative affect(PA and NA) on the relationship between the driver's SDA and SA. The results showed the followings. First, high SDA group collided with the leading vehicle more frequently than low SDA group. Second, neither the driver's trait driving anger(TDA) nor PA/NA yielded significant changes in SA after SDA was induced. Third, high SDA tended to lower SA but this tendency was observed only when the driver's NA was high. These results suggested that SDA than TDA is a significant deteriorating factor of the driver's SA, and more importantly, SDA should be considered with other affect-relating variable such as NA in explaining the effect of SDA on driver's SA and CA.

• Asia Marketing Journal
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• v.8 no.1
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• pp.1-17
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• 2006

A couple of previous studies have warned against the use of homogeneous choice models in assessing the effect of reference price since unaccounted for response heterogeneity may result in spurious reference price effects(Chang, Siddarth and Weinberg 1999; Bell and Lattin 2000). According to Meyer and Kahn(1991), not accounting for consideration set heterogeneity may also bias the effect parameters in the choice model. Therefore, failure to account for these two sources of bias, in fact, have cast doubt on the empirical support for reference price effects in general. In view of aforementioned potential sources of bias, the author investigates the robustness of loss aversion effect in the reference-dependent model after accounting for heterogeneity in response as well as consideration set. The proposed model defines individual household's consideration set based on the posterior distribution of preference obtained from the Empirical Bayes approach. In addition, the same posterior distribution is used to form household-specific reference prices. Response heterogeneity correction is carried out via the Latent Class approach. The proposed model outperforms the Reference-Dependent model that includes the reference price measure most often employed in the previous studies. This implies that as a way of simplifying decision task, consumers restrict their consideration set to a subset of available brands not only in making a brand choice but also in forming reference prices.

• The Journal of the Acoustical Society of Korea
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• v.28 no.3
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• pp.213-221
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• 2009

The time reversal mirror (TRM) method for underwater communications has been developed to improve transmission performance with low complexity. However, digital communication parameters for TRM have not been researched deeply. This paper demonstrates that the TRM scheme obtains spatial diversity gain similar to multiple antennas, and proposes design methodologies of symbol interval, frame duration and transmission protocol for time reversal mirror transmission. Simulation results show that spatial diversity gain is achieved and the effect of ISI decreases as the number of transducer increases.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.146-156
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• 2015

The purpose of this study was to identify the mediating effect of anger expression between covert narcissism and SNS addiction proneness. It was conducted to measure anger expression, covert narcissism, and SNS addiction proneness from 252(132 male, 120 female) university students. The mediating effect was analyzed through Preacher and Hayes' SPSS Macro and bootstrapping analysis. As a result of analysis, first, there were positive relationship among covert narcissism, anger expression, and SNS addiction proneness. Second, anger-out had significant mediating effect within the relationship of covert narcissism and SNS addiction proneness. Third, anger-out had significant mediating effect within the relationship of covert narcissism and disturbance of adaptive life and control failure, preoccupation and tolerance, avoidance of negative emotions. Forth, anger-in and anger-control had significant mediating effect within the relationship of covert narcissism and virtual life orientation and withdrawal. Implications of these results were explored in relation to the importance of covert narcissism and SNS addiction proneness. In addition, this implication and suggestions for future research are provided.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.3
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• pp.65-77
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• 2013

Recent advanced sensors and communication technologies have been widely applied to advanced safety vehicle (ASV) for reducing traffic accident and injury severity. To apply the advanced safety vehicle technologies, it is important to quantify the safety benefits, which is a fundamental for justifying application. This study proposed a methodology for quantifying the effectiveness of the advanced driver assistant system (ADAS), and applied the methodology to lane departure warning system (LDWS) and automatic emergency braking system (AEBS) which are typical advanced driver assistant systems. When the proposed methodology is applied to 2008-2010 gyeonggi-province crash data, LDWS would reduce about 10~14% of relevant crashes such as head-on, run-off-the road, rollover and fixed-object collisions on the road. In addition, AEBS could potentially prevent about 50% of total rear-end crashes. The outcomes of this study support decision making for developing not only vehicular technology but also relevant safety policies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.192-196
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• 2012

In the present study, we examined the effect of the aqueous extract of Rubus coreanus Miquel (RCM-Ex) on scopolamine-induced memory impairment in male ICR mice. Mice were fed the diet containing 100 mg/kg body weight/day of RCM-Ex for 4 weeks. To induce amnesia, scopolamine (an antagonist of muscarinic acetylcholine receptor, 1 mg/kg of body weight) was intraperitoneally injected into mice 30 min before starting the behavior tests. RCM-Ex reversed scopolamine-induced memory impairments in mice as evidence by the passive avoidance test and Morris water maze test. In addition, acetylcholineasterase activities were decreased in the brains of mice treated with RCM-Ex. These results suggest that RCM-Ex may be an effective agent for the prevention of the memory impairment induced by cholinergic dysfunction.