• Journal of Welding and Joining
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• 제17권1호
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• pp.88-96
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• 1999

The effects of root gap on welding residual stress and deformation are dealt with the multi-pass weldment with three kinds(0, 6, 30mm) of root gap by F.E.M common code, and then compared with experiment data. In this analysis, an 100% ramp heat input model was used to avoid numerical convergence problem due to an instantaneous increase in temperature near the fusion zone, and the effect of a moving arc in a two dimensional plane was also included. During the analysis, a small time increment was applied in a period with instantaneous temperature fluctuation while a large time increment was used in the rest period. The residual stress is distributed as symmetric types and maximum value is also equivalent when the weldment with 0mm and 6mm root gap is welded. In the case of 30mm root gap welding, the distribution of the residual stress extends over a wide range as asymmetric types due to the built-up weld, and most of the residual stress is biased in the side of a built-up weld part. In case of 0mm gap welding and 6mm gap welding, a little angular distortion occurs, but the level of deformation is small. When the weldment with 30mm root gap is welded, the angular deformation of the asymmetric types, however, occurs larger than the other specimens. The experimental and the analytic results show good coincidence and indicate that the welding residual stress and deformation distribution of 30 mm root gap specimen may be asymmetric and the amplitude is larger than those of root gap specimen under standard.

• 디지털융복합연구
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• 제16권1호
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• pp.13-20
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• 2018

도시와 농촌이라는 지역적 차이는 여러 가지 다양한 차이를 빚어낸다. 도시와 농촌간에는 경제적 격차, 문화 격차 등등 다양한 차이를 경험하게 된다. 또한 정보에 접근하고 활용하는 데 있어서도 도시와 농촌지역을 차이를 보이고 있다. 본 연구는 정보소외계층 중에서도 특히 정보격차 수준이 다른 집단들에 비해 더 심각하다고 여겨지는 농어민그룹을 대상으로 정보격차와 소득격차간의 관계를 밝혀내고자 하였다. 즉, 농어민들의 정보격차현상이 소득격차에도 영향을 주고 있는가를 살펴보고자 하였다. 이를 위해 매년 정부에서 시행하고 있는 정보격차지수 및 실태조사결과를 바탕으로 농어민들의 정보화수준과 소득과의 관계를 분석하고자 하였다. 연구결과 농어민들의 정보화수준과 가구소득간에는 통계적으로 유의미한 양(+)의 관계가 있음을 밝혀냈다. 또한 그 회귀계수 추세가 양(+)으로 나타나 농어민들에 대한 정보화 수준을 높일 수 있는 정부의 다양한 정보화 정책이 필요함을 시사한다.

• 한국추진공학회지
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• 제20권2호
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• pp.75-85
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• 2016

감쇠기를 사이에 두고 여폭약과 수폭약으로 충전된 파이로 착화기는 격벽의 압력 감쇠 현상과 고에너지 물질의 충격 점화 특성을 갖는다. 고폭약의 폭굉 반응 및 비반응 물질 통과에의 폭압 감쇠와 더불어 격벽의 형상 변화를 모사하기 위해서는 충격 전달에 의한 gap test의 폭굉 모델링이 필요하다. 본 연구에서는 오일러리안 레벨셋 기법이 적용된 다중물질 하이드로 코드를 사용하여 pentolite 작약과 열폭압 RDX의 폭발 반응 및 PMMA gap을 통과하는 충격파 전달을 해석함으로써 화약-격벽간 상호작용 및 임계 두께, 음향 임피던스, go/no-go 기폭 점화에 대한 특성을 정량화하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.521-521
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• 2015

This study evaluated the gap filler radar as an implementation of the 1.5 km CAPPI data in Korea. The use of the 1.5 km CAPPI data was an inevitable choice, given the topography of the Korean Peninsula and the location of the radar. However, there still exists a significant portion of beam blockage, and thus there has been debate about the need to introduce the gap filler radar (or, the gap-filler). This study evaluated the possible benefits of introducing gap-fillers over the Korean Peninsula. As a first step, the error of the radar data was quantified by the G/R ratio and RMSE, and the radar data over the Korean Peninsula were evaluated. Then, the gap-fillers were located where the error was high, whose effect was then evaluated by the decrease in the G/R ratio and RMSE. The results show that the mean values of the G/R ratio and RMSE of the 1.5 m CAPPI data over the Korean Peninsula were estimated to be about 2.5 and 4.5 mm/hr, respectively. Even after the mean-field bias correction, the RMSE of the 1.5 km CAPPI data has not decreased much to be remained very high around 4.4 mm/hr. Unfortunately, the effect of the gap-filler on the 1.5 CAPPI data was also found very small, just 1 - 2%. However, the gap-filler could be beneficial, if the lowest elevation angle data were used instead of the 1.5 km CAPPI data. The effect of five gap-fillers could be up to 7% decrease in RMSE.

• 품질경영학회지
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• 제49권3호
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• pp.313-326
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• 2021

Purpose: Prior studies have sought to find antecedent to improve firm performance. However, research on compensation systems and employees' psychological mechanisms have been relatively limited. In this sense, this study has investigated the impact of compensation gap between TMT and employees on firm performance, and explored the factors that affect the above relationship. Specifically, this study analyzed the direct impact of compensation gap on firm performance. In addition, the process of compensation gap to firm performance is assumed to be significantly influenced by employees' recognized promotion system and satisfaction with TMT. Therefore, we examined moderating effects of both promotion probability and opportunity, and satisfaction with TMT on the relationship between compensation gap and firm performance. Methods: For empirical test, financial variables were collected from TS-2000 database, and moderating variables were collected form Job Planet for listed firms in Korea. We conducted hierarchical regression analysis to test hypotheses. Results: The findings of empirical analysis are as follows. First, compensation gap between TMT and employees had a positive effect on firm performance. Second, when promotion probability and opportunity was high, the effect of compensation gap on firm performance was strengthened. Third, when satisfaction with TMT was high, the positive effect of compensation gap on firm performance was also strengthened. Conclusion: Our findings have expanded prior research on human resource management and labor relation by identifying the positive role of compensation gap between TMT and employees on firm outcome. Moreover, our results also indicated that promotion probability and opportunity, and satisfaction with TMT, which has not been addressed well in previous studies, were important conditions enhancing the positive relationship between compensation gap and firm performance. Finally, this study suggest several theoretical and managerial implication with future research direction.

• 전기학회논문지
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• 제60권5호
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• pp.993-998
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• 2011

In this paper we suggest new criteria for the classification of the electrode gap between common and scan electrodes. The electrode gap is categorized as a short, middle, and long gap according to the criteria. Among these structures, we focus on the erase waveform of a mid-gap structure. we report an unstable discharge arising from the erase ramp period in a mid-gap structure. Based on the Vt close curve, we analyze the unstable discharge at various conditions. Our analysis reveals that the unstable discharge is ignited between surface electrodes and caused by un-erased wall charges accumulated on the outer edges of electrodes. By reducing the voltage level of the last sustain pulse, the problem is solved.

• International Journal of Automotive Technology
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• 제5권3호
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• pp.209-213
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• 2004

The objective of this paper is to introduce the noise reduction characteristics of a double gap system, which is composed of two air-gaps and two partition sheets. The resonance of acoustic modes of an enclosed cavity can be effectively suppressed by installing the double gap system in the cavity. It is revealed from a simple, one-dimensional model that the double gap system is more effective than the single gap system that consists of one air-gap and one partition sheet, in that the former requires a smaller space than the latter. Finally, these theoretical conclusions are verified by comparison experiments using an actually manufactured enclosed cavity, of which the boundary surfaces are made of thick panels that can be assumed as rigid walls.

• 한국유통학회지:유통연구
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• 제1권2호
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• pp.29-52
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• 1996

The objective of this study is to test Parasurman, Zeithaml & Berry(1985)'s service quality gap analysis model, and to confirm reliability and to confirm reliability and validity of the model. The reliability of the model is adopted, but the validity must be retested in the further study. In the results of the gap analysis model, the correlation between consumer expectations and management perceptions of consumer expectations(gap1) was not accepted. The correlation between management perceptions of consumer expectations and service quality specifications(gap2), the correlation between service quality specifications and the service actually delivered(gap3), and the correlation between services delivered and services promised to consumers(gap4) were accepted. To improve domestic telecommunication service quality, practical guides such as standardization of job roles, cooperation among customer-contact persons, communication between managers and employees, evaluation programs for employee's improvement of service quality, appropriate supports for customer-contact persons were suggested. For generalizing the gap model, additional studies under the different contexts and industries will be needed.

• 전자공학회논문지A
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• 제28A권11호
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• pp.874-879
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• 1991

The effect of air gap between specimen and jig on the material constant (permittivity, permeability) and attenuation characteristics of electromagnetic wave absorbers in the coaxial line method was investigated. The presence of a air gap made both permittivity and permeability measured lower than true value, and the tendency was greater in the case of permittivity. An inner gap compared to an outer gop was found to yield a larger difference between measured and true values. The effect of air gap was measured for a Ni0.3Zn0.7Fe2O4, with the gap eliminated by metallizing with Ag-paste. The measured characteristics were in good agreement with corrected values by calculation.

• 한국정밀공학회지
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• 제19권12호
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• pp.45-56
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• 2002

A pneumatic servo system requiring a fine gap control in a photo-electric sensor which is used for a LCD array detection device is introduced. The gap controlled by the pneumatic servo system remains within around 50~80 ${\mu}{\textrm}{m}$, and the system possesses an effect to eliminate undesirable particles on the LCD plate by blowing air out. The air flow rate is initially controlled by a servo valve and expanded by a booster valve, thus the controlled air pressure contributes to maintaining an appropriate gap between the LCD plate and photo-electric sensor An air floating plate of two degrees of freedom is designed and fabricated, and a fine tilting motion control is also implemented by assigning different gap commands. The pressure control and direct gap control are proposed, and each performance is verified experimentally.