• Title/Summary/Keyword: depth effect

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A Study on the Growth intention of Korean and Chinese Co-Founding Startup Companies (한국인과 중국인의 공동창업기업 성장의도에 대한 연구)

  • Kim, A-Hyun;Moon, Jun Hwan;Lee, Jae Bum
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.3
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    • pp.145-158
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    • 2020
  • Because individuals come together to form a society, society has characteristics that are different or similar. Furthermore, as globalization and language acquisition in other countries have been activated, the frequency of studying abroad has increased. While Korea also studies abroad, the number of students coming to Korea from other countries continues to increase, increasing. In particular, when there was interest in start-up businesses, the factors were discovered through exploratory research in order to identify factors affecting the level of growth in start-ups when they had different nationalities. In order to conduct exploratory research, the government wanted to check more in-depth information through semi-structured interviews with co-founder companies composed of Koreans and Chinese. The main keywords were repeated or emphasized continuously during the interview, and other keywords were obtained through additional questions. As a result, it has been confirmed that self-acceptance, cultural distance, entrepreneurship, knowledge quality and growth are very large keywords in the co-founding start-up of different countries. The proposition was established as having a relationship of justice with self-acceptance, cultural distance and entrepreneurship as independent variables and with the degree of growth as dependent variables. In particular, in the case of co-founding with different nationalities, the most important knowledge quality was represented the effect of reverse U in each relationship (the relationship between self-acceptance, cultural distance, entrepreneurship and growth).

Numerical Simulation of Flow Characteristics behind a Circular Patch of Vegetation using a Two-Dimensional Numerical Model (2차원 수치모형을 이용한 원형군락 하류의 흐름특성 수치모의)

  • Kim, Hyung Suk;Park, Moonhyeong
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.891-903
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    • 2015
  • This paper presents numerical simulations of flow around a circular patch of vegetation using a depth-averaged two-dimensional numerical model which is capable of simulating flow structure in vegetated open channel. In order to account for vegetation effect, drag force terms are included in governing equations. Numerical simulations are conducted with various solid volume fractions (SVF). Flow passes through a circular patch and low velocity region, which is called wake region, is formed downstream of the patch. When SVF is larger than 0.08, a recirculation is observed. The location of the recirculation is moved further downstream as SVF decreases. Von-$K{\acute{a}}rm{\acute{a}}n$ vortex street is developed beyond the wake region due to interaction between two shear layers induced by a circular patch of vegetation. The vortex is developed as SVF is larger than 0.08, and the location of the vortex is consistent with the maximum of turbulence kinetic energy. The location of the peak of turbulence kinetic energy is moved further downstream as SVF decreases.

A STUDY ON THE EFFECT OF BASE MATERIALS TO PROTECT THE CERVICAL LEAKAGE OF BLEACHING AGENTS (표백제의 치경부 누출을 방지하기 위한 각종 이장재의 효과에 관한 연구)

  • Song, Byeong-Choon;Cho, Young-Gon
    • Restorative Dentistry and Endodontics
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    • v.19 no.2
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    • pp.585-601
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    • 1994
  • The purpose of this study was to evaluate the ability of several intracoronal base materials to prevent cervical leakage of a bleaching agent into the dentinal tubules and along the root canal. In this study, thirty-two anterior teeth were used. After lingual access was prepared in each tooth, tooth was instrumented with a step-back technique to a Nos. 40-50 using K-type files. All teeth were obturated with a lateral condensation technique. Excess gutta percha was removed with a warm instrument to the facial level of the CEJ. Teeth were divided into four groups : Teeth in control group were not filled with base material. Teeth in groups 1, 2, and 3 had 2mm of gutta percha removed with a warm instrument, then Dycal, Fuki II LC and Z-100 were filled with palstic instruments on the top of the gutta percha respectively. All teeth were bleached for 7 days, fresh bleach was added for another 7 days, then a 10 % methylene blue dye was placed inside the access preparation. They were stored at $37^{\circ}C$ and $100^{\circ}C$ humidity for 5 days. Each tooth was sectioned perpendicular to the long axis using a diamond disk. Initial cuts were made at the most coronal level of facial and lingual CEJ's, then another cuts continued appically in the levels of 0.5mm, 1.5mm, and 2.0mm respectively. The amount of dye leakage through the dentinal tubules was determined at each cut section. In addition, when the cut specimen was determined to be last penetration of any dye, this level was recorded as depth of apical leakage from the coronal terminus of the gutta percha, Dycal, Fuji II LC and Z-100. The acquired data were analyzed by Tukey's Multiple Range Test adn Cochran-Mantel-Haenszel Test to see if there was any statistically significant difference in dye penetration and linear apical leakage among the groups. The results were as follows : 1. Control group at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 AND 3 at level of 2.0mm showed the least dye penetration through the facial or lingual dentinal tubules, but there were no significant difference among three groups. 2. Group 2 at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 and 3 at level of 2.0mm showed the least dye penetration through the proximal dentinal tubules, but there were no significant difference among control group, group 2, and group 3. 3. Group 1 showed the greatest dye penetration through the facial or lingual and proximal dentinal tubules at all levels, and there were significant difference with other three groups. 4. Control group and group 1 showed 2mm apical dye leakage at facial or lingual and proximal aspects, group 2 showed 1.5mm, and group 3 showed 0.5mm.

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Educational Effects of Flipped Learning on Fashion Practical Course (패션 실기 수업에 적용한 플립드 러닝의 교육적 효과)

  • Kim, Jang-Hyeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.497-508
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    • 2020
  • The paradigm focusing on learner-centered classes and the introduction of flipped learning through the connection between online and offline have been increasing. This study proved the educational effect by applying flipped learning to the basic draping course within the fashion practical course and revealed the implications for flipped learning from the instructor's perspective. The research methods are theatrical research and model development research in order to guide basic drape utilizing flipped learning. The study results revealed that learners' satisfaction was very high about the basic draping course combined with flipped learning, and it showed that students were very satisfied with the learning-related video because it can compensate for the decrease in education efficiency according to the number of attendees and improve education. Improvements shall include technical and content supplementation of video learning materials and presentation of documented learning materials, in addition to video materials. From the instructor's perspective, time needs to be set aside for video shooting and editing, a view of the composition of education from the learner's perspective, and an in-depth understanding of the instructor's curriculum for flipped learning design.

Morphological Features of Bedforms and their Changes due to Marine Sand Mining in Southern Gyeonggi Bay (경기만 남부에 발달된 해저지형의 형태적 특징 및 해사채취에 의한 변화)

  • Kum, Byung-Cheol;Shin, Dong-Hyeok;Jung, Seom-Kyu;Jang, Seok;Jang, Nam-Do;Oh, Jae-Kyung
    • Ocean and Polar Research
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    • v.32 no.4
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    • pp.337-350
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    • 2010
  • This study conducted sedimentological and geophysical surveys for 3 years (2006-2008) in southern Gyeonggi Bay, Korea to elucidate temporal changes in subaqueous dune morphology on a sand ridge trending northeast to southwest that has been excavated by marine sand mining. The sand ridge (~20 m in height, ~2 km in width and 3~4 km in length) has a steep slope on the NW side and a gentle slope on the SE side, creating an asymmetric profile. Large (10~100 m in length) and very large (>100 m in length) dunes occurring on the SE side of the ridge show a northeastward asymmetrical shape, whereas dunes on the NW side destroyed by marine sand mining display a southwestward asymmetry. The comparison between Flemming (1988)'s correlation and the height-length correlation of this study indicates that tidal current and availability of sand sediment are major controlling factors to the development and maintenance of dunes. Depth and sedimentary characteristics (grain size) are not likely to be major controlling factors, but indirectly influence dune growth by hydrological and sedimentary processes. The length and the height of dunes decrease toward the southeastern trough away from the crest of the ridge. These features result from the decrease of tidal current and sediment availability. The length and the height of dunes on the southeast side decrease gradually over time. This is a result of the interaction between tidal current and the decrease in sediment availability due to sediment extraction by marine sand mining. Marine sand mining has destroyed the dunes directly, causing irregular shapes of shorter length and lower height. The coarse fraction of suspended sediments is transported and deposited very close to the sand pit. By contrast, relatively fine sediments are transported by the tidal current and deposited over a wide range by the settling-lag effect, resulting in a decrease of sediment grain size in the area where suspended sediments are deposited. In addition, marine sand mining, decreases the height of dunes. Therefore, morphological and sedimentological characteristics of dunes around the sand pits will be significantly changed by future sand mining activities.

The Effect of Corporate Social Responsibilities on the Quality of Corporate Reporting (기업의 사회책임이 기업경영보고의 질에 미치는 영향)

  • Jeong, Kap-Soo;Park, Cheong-Kyu
    • Journal of Distribution Science
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    • v.14 no.6
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    • pp.75-80
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    • 2016
  • Purpose - A growing demand for sustainability reporting has placed pressure on firms with non-financial information that affects firm valuation, growth, and development. In particular, a number of researchers have investigated various topics in Corporate Social Responsibility (CSR), non-financial information. Prior studies suggest that CSR may affect corporate outcomes like corporate reporting, financial performance, and disclosures. However, the results from prior studies are not clear whether CSR affects corporate outcomes. This is partially due to the measurement issues with CSR. In this study, we examine whether CSR affects the quality of corporate reporting, one of the popular measures in corporate outcomes. We find an evidence that CSR positively affects the quality of corporate reporting. Research design, data, and methodology - In this study, we collected a unique dataset of CSR from MSCI. Total 169 firms listed in the Korean Stock Exchange from 2011 to 2014 were collected and analysed with the detailed CSR reports. Using a correlation test, we found a weak association between CSR and the quality of corporate reporting. However, the regression tests provided a strong relationship between CSR and the quality of corporate reporting after controlling for other variables that may affect the quality of corporate reporting. Additionally, we calculated the t-statistics based on heteroskedaticity-consistent standard errors (White, 1980). Results - Before we run the regression test, we sort the measures of the two dependent variables into each rating of CSR (from AAA to CCC). The results indicate that the quality of corporate reporting measured by discretionary accruals and performance-matched discretionary accruals monotonically decrease as the CSR ratings increase. This supports our hypothesis. In the regression tests, the coefficient on MJDA (PMDA) is -0.183 (-0.173) and significant at the 5% level. We can interpret the results as CSR affecting the quality of corporate reporting in positive ways. Other coefficients on control variables are consistent with prior studies. For example, the coefficients on both LOSS and LEV are positive and significant at conventional level, meaning that firms with financial difficulty may harm their quality of corporate reporting. Conclusion - We found an evidence that CSR is positively associated with the quality of corporate reporting. This study contributes to the literature in various ways. First, this study extends the line of CSR research by providing additional evidence in the setting of ethical behaviors by managements. This is consistent with the hypothesis and supports the results of prior studies. Second, to the best of my knowledge, this is the first study using the MSCI CSR ratings. In contrast with prior studies using different measures of CSR, the MSCI CSR ratings allow us to provide in-depth analysis. Third, the additional measure of dependent variable (PMDA) allows us to improve the robustness of our results. Overall, the results provided this study to extend the findings in prior studies by providing incremental evidence.

An Experimental Study on the Clogging of Sand Filter in a Model Filtration-Pond (천변여과지 모형에서 여재모래의 폐색현상 실험연구)

  • Jeong, Jae-Min;Kim, Seung-Hyun
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.9
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    • pp.681-685
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    • 2013
  • A pilot-scale sand-box experiment was performed in order to investigate the effect of cross-flow velocity on the clogging of the filter sand in a model filtration pond. The clogging phenomenon was observed during the operation with the cross-flow varied in stages in a range of 0~40 cm/sec, and the experimental result was analyzed using a numerical code. Results showed that the cross-flow velocity in this range had no influence on the development of clogging and that clogging occurred mostly on the filter-surface. It was found that while the production rate decreased from $5m^3/m^2-day$ to $3m^3/m^2-day$ the clogging coefficient of the top 50 cm layer increased up to about 30,000 sec, which corresponded to 87% of the clogging coefficient of the total 2.4 m layer. Of the clogging coefficient of the top 50 cm layer, surface clogging constituted 90% while the other 10% was intermediate clogging. It was also found that the surface clogging increased while the intermediate clogging remained constant as the operation continued, and that filtrate turbidity along the filtration depth remained constant in spite of the increase in clogging.

Study for Conductive and Non-conductive Multi-layers Depth Profiling Analysis of Radio Frequency Gas-jet Boosted Glow Discharge Spectrometry (Modified Gas-jet Boosted Radio-frequency Glow Discharge 셀의 개발 및 최적화에 관한 연구)

  • Cho, Won Bo;Borden, Stuart;Jeong, Jong Pil;Kang, Won Kyu;Kim, Kyu Whan;Kim, Hyo Jin
    • Analytical Science and Technology
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    • v.15 no.2
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    • pp.108-114
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    • 2002
  • The new system using a glow discharge atomic emission spectrometer for the direct analysis of solid samples has been developed and characterized. The system was consisted of new glow discharge cell improved previous gas-jet boosted nozzle and radio-frequency power supply. In the case of previous type glow discharge chamber, it had been fitted trace analysis of low alloy steel with low discharge power, because it was to decrease redeposition and increase sample weight loss. But it had a problem that plasma becomes unstale due to increased sample weight loss and redeposition resulting from the high discharge power. Because of being problem of previous glow discharge, it is impossible to analyze using high power. The modified gas-jet boosted glow discharge to solve this problem would improve to be less sample loss rate of modified nozzle than sample loss rate of previous nozzle on the equal discharge condition, and improve to increase stability of plasma. The effect of discharge parameters such as discharge pressure, gas flow rate and power on the sample loss rate, emission intensity has been studied to find optimum discharge conditions. The calibration curves of Fe were obtained with 3 low-alloy samples.

A Study on the Illustration Content Used in Secondary School Textbooks : Focusing on the 'Society.Culture' Textbooks (중등학교 교과서에서 삽화 콘텐츠 활용 연구 : 고등학교 '사회.문화' 교과서를 중심으로)

  • Min, Il-Hong
    • Cartoon and Animation Studies
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    • s.18
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    • pp.57-72
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    • 2010
  • Textbooks used in Information Society need to use many illustrations and pictures which have positive effect in motivating and triggering students to study. "Pictures mean more than thousands of the word" says that it is significant to use media in class through visual materials. To meet the needs of the times, I examined one of the units, "IV Understanding Humans and Cultural Phenomena", among 7 authorized 'Society Culture' textbooks, so that there are 123 illustrations and 342 pictures that the percentage of them was 35.65% totally in the unit. On the examination of the frequency of using contents in each category, the illustrations are used 59 times (47.96%) in the research activity and the pictures 145 times (42.4%) in the context, which are most frequently used. Also on the examination into the actual states using contents among 'Society Culture' teachers by in-depth interviewing, they often use them when their class starts. And they require more increase in the illustrations than the pictures for easy and clear understanding and need more contents offering in the research activity to help students to study more interesting. Finally, on the result of the analysis of contents used in textbooks, exemplary cases were available to convey enough information without reading the context in the textbook because the proposed illustrations expressed the research activity's subject and the context's subject effectively. Even more, one illustration was able to indicate the sub-unit's subject while also presenting the content to be learned in the unit. However, improper cases included illustrations which are somewhat unrealistic or difficult to understand. Further, there are also some illustrations which are not related to the context. If these points are revised in the future, textbooks would be better.

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A Study on Optimum Ventilation System in the Deep Coal Mine (심부 석탄광산의 환기시스템 최적화 연구)

  • Kwon, Joon Uk;Kim, Sun Myung;Kim, Yun Kwang;Jang, Yun Ho
    • Tunnel and Underground Space
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    • v.25 no.2
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    • pp.186-198
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    • 2015
  • This paper aims for the ultimate goal to optimize the work place environment through assuring the optimal required ventilation rate based on the analysis of the airflow. The working environment is deteriorated due to a rise in temperature of a coal mine caused by increase of its depth and carriage tunnels. To improve the environment, the ventilation evaluation on J coal mine is carried out and the effect of a length of the tunnel on the temperature to enhance the ventilation efficiency in the subsurface is numerically analyzed. The analysis shows that J coal mine needs $17,831m^3/min$ for in-flow ventilation rate but the total input air flowrate is $16,474m^3/min$, $1,357m^3/min$ of in-flow ventilation rate shortage. The temperatures were predicted on the two developed models of J mine, and VnetPC that is a numerical program for the flowrate prediction. The result of the simulation notices the temperature in the case of developing all 4 areas of -425ML as a first model is predicted 29.30 at the main gangway 9X of C section and in the case of developing 3 areas of -425ML excepting A area as a second model, it is predicted 27.45 Celsius degrees.