• Title/Summary/Keyword: Impact Mechanism

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Variation of Harbor Response due to Construction of A New Port in Youngil Bay (영일만 신항 건설에 따른 항만 정온도의 변화)

  • Kim, Ji-Yeon;Lee, Joong-Woo;Lee, Hak-Seung;Yang, Sang-Yong
    • Journal of Navigation and Port Research
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    • v.28 no.5
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    • pp.421-428
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    • 2004
  • Introduction of wave model, considered the effect of shoaling, refraction, diffraction, partial reflection, bottom friction, breaking at the coastal waters of complex bathymetry, is a very important factor for most coastal engineering design and disaster prevention problems. As waves move from deeper waters to shallow coastal waters, the fundamental wave parameters will change and the wave energy is redistributed along wave crests due to the depth variation, the presence of islands, coastal protection structures, irregularities of the enclosing shore boundaries, and other geological features. Moreover, waves undergo severe change inside the surf zone where wave breaking occurs and in the regions where reflected waves from coastline and structural boundaries interact with the incident waves. Therefore, the application of mild-slope equation model in this field would help for understanding of wave transformation mechanism where many other models could not deal with up to now. The purpose of this study is to form a extended mild-slope equation wave model and make comparison and analysis on variation of harbor responses in the vicinities of Pohang Old Harbor and Pohang New Port, etc. due to construction of New Port in Youngil Bay. This type of trial might be a milestone for port development in macroscale, where the induced impact analysis in the existing port due to the development could be easily neglected.

An Analysis of Panel Data on the Web-accessibility Policies of Local Governments in Korea (우리나라 웹 접근성 정책 영향요인 분석 - 16개 광역자치단체 패널데이터를 중심으로 -)

  • JIN, Sangki;HYUN, Joonho
    • Informatization Policy
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    • v.18 no.4
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    • pp.42-58
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    • 2011
  • This paper starts from one question: what are the key factors of the web accessibility policy, which is significant for realizing equity in the web and enhancing human dignity in the information society. To find significant factors for complying with web accessibility, this paper analyzes panel data of 16 Korean local governments (for five years: 2004-2009) according to the research design which is based on the demand and supply balance model and consists of four variables : 'legal and institutional environment (including legal infrastructure)', 'financial foundation (fiscal self-reliance ratio)', 'policy inputs (amount of imformatization budget, employee of information experts)'and 'policy demand (internet usage rate, the number of disabled people and elderly people)'. From the results of this study, this paper can explain the mechanism and impact factors on the web accessibility policy of Korean local governments. Some factors are critical to improve web accessibility: (1) the importance of policy demand, (2) the importance of policy inputs, (3) the importance of legal and institutional environment. Finally, this paper concludes with some suggestions to enhance the web accessibility capacity for Korean local governments: (1) improve awareness on web accessibility, (2) develop a standard and invest R&D on web accessibility, (3) foster experts in web accessibility.

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Analysis of Particle Morphology Change and Discrete Element Method (DEM) with Different Grinding Media in Metal-based Composite Fabrication Process Using Stirred Ball Mill (교반볼밀을 이용한 금속기반 복합재 제조공정에서 다른 분쇄매체차이에 대한 입자형상변화와 DEM 시뮬레이션 해석)

  • Batjargal, Uyanga;Bor, Amgalan;Batchuluun, Ichinkhorloo;Lee, Jehyun;Choi, Heekyu
    • Korean Chemical Engineering Research
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    • v.55 no.4
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    • pp.456-466
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    • 2017
  • This work investigated the particle morphology change to difference in milling media in a metal based composite fabrication process using a stirred ball mill with ball behavior of DEM simulation. A simulation of the three dimensional motion of grinding media in the stirred ball mill for the research of grinding mechanism to clarify the force, kinetic energy, and medium velocity of grinding media were calculated. In addition, the rotational speed of the stirred ball mill was changed to the experimental conditions for the composite fabrication, and change of the input energy was also calculated while changing the ball material, the flow velocity, and the friction coefficient under the same conditions. As the rotating speed of the stirred ball mill increased, the impact energy between the grinding media to media, media to wall, and media and the stirrer increased quantitatively. Also, we could clearly analyze the change of the particle morphology under the same experimental conditions, and it was found that the ball behavior greatly influences in the particle morphology changes.

Simulation of Air Quality Over South Korea Using the WRF-Chem Model: Impacts of Chemical Initial and Lateral Boundary Conditions (WRF-Chem 모형을 이용한 한반도 대기질 모의: 화학 초기 및 측면 경계 조건의 영향)

  • Lee, Jae-Hyeong;Chang, Lim-Seok;Lee, Sang-Hyun
    • Atmosphere
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    • v.25 no.4
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    • pp.639-657
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    • 2015
  • There is an increasing need to improve the air quality over South Korea to protect public health from local and remote anthropogenic pollutant emissions that are in an increasing trend. Here, we evaluate the performance of the WRF-Chem (Weather Research and Forecasting-Chemistry) model in simulating near-surface air quality of major Korean cities, and investigate the impacts of time-varying chemical initial and lateral boundary conditions (IC/BCs) on the air quality simulation using a chemical downscaling technique. The model domain was configured over the East Asian region and anthropogenic MICS-Asia 2010 emissions and biogenic MEGAN-2 emissions were applied with RACM gaseous chemistry and MADE/SORGAM aerosol mechanism. Two simulations were conducted for a 30-days period on April 2010 with chemical IC/BCs from the WRF-Chem default chemical species profiles ('WRF experiment') and the MOZART-4 (Model for OZone And Related chemical Tracers version 4) ('WRF_MOZART experiment'), respectively. The WRF_MOZART experiment has showed a better performance to predict near-surface CO, $NO_2$, $SO_2$, and $O_3$ mixing ratios at 7 major Korean cities than the WRF experiment, showing lower mean bias error (MBE) and higher index of agreement (IOA). The quantitative impacts of the chemical IC/BCs have depended on atmospheric residence time of the pollutants as well as the relative difference of chemical mixing ratios between the WRF and WRF_MOZART experiments at the lateral boundaries. Specifically, the WRF_MOZART experiment has reduced MBE in CO and O3 mixing ratios by 60~80 ppb and 5~10 ppb over South Korea than those in the WRF-Chem default simulation, while it has a marginal impact on $NO_2$ and $SO_2$ mixing ratios. Without using MOZART-4 chemical IC, the WRF simulation has required approximately 6-days chemical spin-up time for the East Asian model domain. Overall, the results indicate that realistic chemical IC/BCs are prerequisite in the WRF-Chem simulation to improve a forecast skill of local air quality over South Korea, even in case the model domain is sufficiently large to represent anthropogenic emissions from China, Japan, and South Korea.

A Study on the Profitability of the Commercial Bank in Terms of Interest Rate Marketization : Based on FMOLS Model (FMOLS 모형을 이용한 상업은행 수익성에 대한 연구 : 금리 시장화의 시각에서)

  • He, Yugang
    • The Journal of Industrial Distribution & Business
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    • v.9 no.8
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    • pp.41-50
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    • 2018
  • Purpose - As an important participant in the financial markets, the commercial bank will be impacted by the interest rate marketization. Owing to the special condition of China, this paper tries to explore the impact of operating mechanisms between interest rate marketization and the profitability of the commercial Bank. Research design, data and methodology - This paper applies time series data from 2005 to 2016. Due to the short period of time series, autocorrelation often occurs. Therefore, the fully modified least squares(FMOLS) will be used to conduct an empirical analysis. The reason is that it can move off the autocorrelation between variables and disturbance term. And FMOLS also can make estimated cointegrating parameters closed to normal distribution. More importantly, in order to avoid spurious regressions, the Augmented Dickey-Fuller Test will be used to verify the stationarity of all variables. The total return of asset is treated as the profitability of commercial bank. The net interest spread is treated as a measurement of interest rate marketization. Both are regarded as dependent variables. The non-interest income or gross revenues and impaired loans or gross loans are treated as independent variables. The sixteen representative listed commercial banks are divided into three categories (state-owned, share-holding and city-owned) to conduct an estimation. Results - Via empirical analysis, the findings show that the net interest spread has a positive effect on the profitability of the commercial bank. More specifically, 1% increase in the net interest spread will lead 0.157% increase in the profitability of state-owned commercial bank, 0.269% increase in the profitability of share-holding commercial bank and 0.263% increase in the profitability of city-owned commercial bank. If regarding the sixteen listed commercial city as a whole, 1% increase in the net interest spread will lead 0.267% increase in the profitability of the commercial bank. Conclusions - As the interest rate marketization, the importance of interest rate on the profitability of commercial bank has become more and more significant. The empirical evidences also prove that the net interest spread can bring about the change of the commercial bank's profitability. Therefore, policy-makers of commercial banks should fully understand the operating mechanism between them.

Numerical Analysis of Debris Flow Using Drone Images and NFLOW (드론 영상 및 NFLOW를 활용한 토석류 수치해석 연구)

  • Lee, Seungjoo;Lim, Hyuntaek;Lim, Moojae;Lee, Eungbeom;Lee, Kang-Il;Kim, Yongseong
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.3
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    • pp.1-8
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    • 2020
  • In this study, numerical analysis of debris flow was performed using the SPH (Smoothed Particle Hydrodynamics) technique to analyze the mechanism of debris flow, and the applicability of soil parameters was verified by comparison with previous studies. In addition, after performing aerial photographic survey using a drone, a topographic model was created based on this survey to check the applicability of the site to the valley part of Jagul Mountain basin. And after numerical analysis of debris flow was performed using NFLOW, and the result was compared and analyzed with the existing satellite image based method. As a result of this study, the numerical analysis method using drone image and NFLOW was found to have a higher applicability to predicting the impact of debris flow, because it can reflect the actual topography better than the existing method based on satellite imagery. Therefore, it is considered that this study can be used as basic data to establish the preventive measures for debris flow such as location selection of the eruption control dam.

Anti-lymphoma Activities of Phlojodicarpus sibiricus and Artemisia kruhsiana Besser Extracts (Phlojodicarpus sibiricus와 Artemisia kruhsiana Besser 추출물의 항림프종 효과 분석)

  • Kim, Jisu;Kim, Dong Uk;Nam, Jehyun;Jeon, Byeol Eun;Okhlopkova, Zhanna M.;Zulfugarov, Ismayil S.;Kim, Sang-Woo
    • Journal of Life Science
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    • v.30 no.4
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    • pp.379-385
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    • 2020
  • Phlojodicarpus sibiricus and Artemisia kruhsiana Besser are medicinal plants traditionally used in Russia. Phlojodicarpus sibiricus extracts (PSE) have been shown to have anti-obesity properties, and Artemisia kruhsiana Besser extracts (AKBE) contain terpenoid compounds that exert various medicinal effects. Here, we investigated the potential pro-apoptotic effects of PSE and AKBE in diffuse large B-cell lymphoma (DLBCL) and elucidated the underlying mechanism. PSE and AKBE treatment of six DLBCL cell lines with various genetic abnormalities effectively reduced cell viability in a dose-dependent manner, while having a minimal impact on the survival of normal murine bone marrow cells and splenocytes. This suggests that the cytotoxic effects of PSE and AKBE are specific to DLBCL cells. Therefore, we expect limited side effects when these plant extracts are administered to DLBCL patients. Our JC-1 assays demonstrate that the pro-apoptotic effects of these plant extracts are produced by a reduction of anti-apoptotic Bcl-2 family members and, thereby, disruption of the mitochondrial membrane potential. Moreover, PSE and AKBE induce cell death independently of Myc, whose abnormalities are frequently observed in patients with DLBCL and are associated with poor prognosis. Our findings reveal hitherto uncharacterized pro-apoptotic effects of PSE and AKBE in DLBCL. Isolation of single compounds with anti-lymphoma activities should be pursued further.

Analysis of Mechanism for Photovoltaic Properties and Bypass Diode of Crystalline Silicon and CuInxGa(1-x)Se2 Module in Partial Shading Effect (결정질 실리콘 및 CuInxGa(1-x)Se2 모듈의 부분음영에 따른 태양전지 특성 변화 및 바이패스 다이오드의 작동 메커니즘 분석)

  • Lee, Ji Eun;Bae, Soohyun;Oh, Wonwook;Kang, Yoonmook;Kim, Donghwan;Lee, Hae-Seok
    • Korean Journal of Materials Research
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    • v.25 no.4
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    • pp.196-201
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    • 2015
  • This paper presents the impact of partial shading on $CuIn_xGa_{(1-x)}Se_2(CIGS)$ photovoltaic(PV) modules with bypass diodes. When the CIGS PV modules were partially shaded, the modules were under conditions of partial reverse bias. We investigated the characterization of the bypass diode and solar cell properties of the CIGS PV modules when these was partially shaded, comparing the results with those for a crystalline silicon module. In crystalline silicon modules, the bypass diode was operated at a partial shade modules of 1.67 % shading. This protected the crystalline silicon module from hot spot damage. In CIGS thin film modules, on the other hand, the bypass diode was not operated before 20 % shading. This caused damage because of hotspots, which occurred as wormlike defects in the CIGS thin film module. Moreover, the bypass diode adapted to the CIGS thin film module was operated fully at 60% shading, while the CIGS thin film module was not operated under these conditions. It is known that the bypass diode adapted to the CIGS thin film module operated more slowly than that of the crystalline silicon module; this bypass diode also failed to protect the module from damage. This was because of the reverse saturation current of the CIGS thin film, $1.99{\times}10^{-5}A/cm^2$, which was higher than that of crystalline silicon, $8.11{\times}10^{-7}A/cm^2$.

A Study on the impact of the changes in international emissions trade market on non-CO2 CDM projects (국제 배출권 거래 시장의 제도변화가 국내 비(非)CO2 CDM 사업에 미치는 영향 분석)

  • Lee, Eungkyoon;Hwang, Minsup;Lee, Myung-Kyoon
    • Environmental and Resource Economics Review
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    • v.23 no.2
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    • pp.157-185
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    • 2014
  • The Kyoto Protocol has extended its life until 2020 by the decision at COP18 in Doha, Qatar in 2012. So has the Kyoto Mechanism of CDM, JI, and ETS. Nonetheless, the sustainability of CDM projects is jeopardized by the recent rule changes in the international emissions trade market such as EU ETS and the price decrease in emission credits. In particular, the domestic CDM projects reducing non-$CO_2$ GHG emissions are being directly affected. This study examines the trend of carbon credit price change in the international market. It also examines how the rule changes in the international emissions trade market have affected domestic non-$CO_2$ CDM projects through which mechanisms. The policy implications drawn from this study is two-fold: it suggests how the government can assist the project developers in utilizing GHG emission reduction technologies and the market in promoting investment environment before the domestic ETS enters into effect in 2015; apart from possible measures within ETS, an additional measures such as bilateral carbon offset system is suggested to help the private sector reduce uncertainty in investment and increase options to choose.

Motivated Reasoning as Obstacle of Scientific Thinking: Focus on the Cases of Next-Generation Researchers in the Field of Science and Technology (과학적 사고의 걸림돌 동기기반추론 -과학기술 분야 학문후속세대들의 사례를 중심으로-)

  • Shin, Sein;Lee, Jun-Ki;Ha, Minsu
    • Journal of The Korean Association For Science Education
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    • v.38 no.5
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    • pp.635-647
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    • 2018
  • Motivated reasoning refers to biased reasoning that is affected by motivation to achieve a particular result or goal. In this study, we attempted a theoretical study on motivated reasoning that hinders the development of scientific thinking and empirical study on actual context of motivated reasoning in the research experiences of next-generation Korean researchers in the field of science and technology. To be specific, literature reviews were conducted to explore the psychological meaning of motivated reasoning and its negative impact on scientific thinking and science research. To understand the substantial meaning and context of motivated reasoning in the field of real science and technology research, we conducted in-depth interviews with eight graduate students and one young science and technology researcher. As a result of the literature reviews, we found out that motivated reasoning can interfere with the proper theory and data coordination, which is the core process of scientific thinking at the individual level. At the socio-cultural level, it can lead to cessation of constructing scientific knowledge and it can act as a mechanism in the process of using science for specific socio-cultural beliefs or purposes, thereby hindering the development of science and technology based on rationale and objective scientific thinking. Quantitative analysis with in-depth interview data showed that graduate students and the young researcher's experienced motivated reasoning results in trying to protect prior beliefs, make hasty conclusions, protecting socio-cultural belief or rationalizing decisions made by their community. Their motivated reasoning could become an obstacle in constructing valid science and technology knowledge through appropriate theory and evidence coordination. Based on these findings we discussed science education for improving scientific thinking.