• Title/Summary/Keyword: $K^+-channel$

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Does Online Social Network Contribute to WOM Effect on Product Sales? (온라인 소셜네트워크의 제품판매 관련 구전효과에 대한 기여도 분석)

  • Lee, Ju-Yoon;Son, In-Soo;Lee, Dong-Won
    • Journal of Intelligence and Information Systems
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    • v.18 no.2
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    • pp.85-105
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    • 2012
  • In recent years, IT advancement has brought out the new Internet communication environment such as online social network services, where people are connected in global network without temporal and spatial limitation. The popular use of online social network helps people share their experience and preference for specific products and services, thus holding large potential to significantly affect firms' business performance through Word-of-Mouth (WOM). This study examines the role of online social network in raising WOM effect on the movie industry by comparing with the similar role of Internet portal, another major online communication channel. Analyzing 109 movies and data from both Twitter and Naver movie, we found that significant WOM effect exists simultaneously in both Twitter and Naver movie. However, we also found that different figures of online viral effects exist depending on the popularity of movies. In the hit movie group, before the movie release, the WOM effect occurs only in Twitter while the WOM effect arises in both Twitter and Naver movie at the same time after the movie release. In the less-popular (or niche) movie group, the WOM effect occurs in both Twitter and Naver movie only before the movie release. Our findings not only deepen theoretical insights into different roles of the two online communication channels in provoking the WOM effect on entertainment products but also provide practitioners with incentive to utilize SNS as strategic marketing platform to enhance their brand reputations.

Influencing Factors on the Knowledge-Transfer Channel of the Korean Academics Engaged in Science and Engineering (한국 이공계 대학교수 지식이전 경로의 영향요인)

  • Kwon, Ki-Seok;Park, Mun-Su
    • Journal of Information Technology and Architecture
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    • v.9 no.3
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    • pp.287-301
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    • 2012
  • Against Nonaka's seminal work in 1999, this study aims to investigate various influencing factors on knowledge-transfer channels of Korean academics. To do this, we surveyed 20,000 Korean academics in science and engineering with regard to factors involved in their formal and informal collaborative activities with firms. In particular, we focus on the individual characteristics of the academics when the channels are changed from informal channels (e.g. consulting) to formal channels (e.g. licensing), as the codification of knowledge is important when it is spilled over. According to the results, male academics with a longer career and in the field of applied disciplines in a big laboratories are likely to join the transformation of the channels. Interestingly, application capacity as measured by the number of patent application is significantly and positively related to the participation of formal channels. In contrast, scientific capacity as measured by the number of papers is significantly and negatively, or in some case weakly, related to the participation. Finally, based on the findings, some policy implications are put forwarded.

A Study on the Cun, Guan, Chi (Inch, Bar, Cubit) from the Elementary Course for Medicine{Yi Xue Ru Men) (의학입문(醫學入門)의 촌관척(寸關尺)에 관한 고찰(考察))

  • Lee, Soo-Kyeung;Park, Won-Hwan
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.9 no.2
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    • pp.10-24
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    • 2005
  • Background and Purpose: Feeling the pulse is based on the pulse condition and alteration to observe the condition of the human body's health and by using a healthy person's pulse as a standard we are able to analyze the patient's pulse to find the attacked channel and collateral, viscera and bowels and understand the pathology such as diseases caused by exogenous evil, disorder of internal organs, and seven modes of emotions. Observing the color and shade of the patient's face, listening carefully to the sound of the patient, and feeling the pulse are methods in accordance with Su Wen 'Plain Questions', 'The Classic on Difficulty' (5th century B.C. Bianque), 'The Classic of Sphymology' (280 A.D. Wang Xi), 'Pulse Formulas' (1189 A.D. Cui Jiayan), and is systematically edited for those who have started studying to easily reach the profound state. Therefore, 'The Elementary Course for Medicine' has been used from ancient times as the textbook for diagnostics. Methods: In this Study, we will inspect commonly used pulse feeling methods, the inch, bar, cubit thesis, the viscera and bowels thesis from The Elementary Course for Medicine and inquire the difference of the text from 'Plain Questions of Huangdi's Internal Classic', 'Treatise on Febrile Diseases', 'Classic on Difficulty'. Results and Conclusion: 1. In 'The Elementary Course for Medicine' the site of the wrist along the pulsation of the radial artery is divided into inch, bar, cubit and has defined the inch, bar, cubit crossways. 2. In 'The Elementary Course of Medicine' the inch, bar, cubit for the left hand and right hand is subjected to each viscera and bowel. By assigning the left hand's inch, bar, cubit to the cardial orb, the hepatic orb, the renal orb, and the right hand's inch, bar, cubit to the pulmonic orb, the splenic orb, the vital gate it has been able to feel the pulse for each viscera and bowel by using the interpromoting and interacting relation of the five evolutive phases.

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Estimation of Surface Reflectance by Utilizing Single Visible Reflectance from COMS Meteorological Imager - Analysis of BAOD correction effect - (천리안위성 기상 탑재체의 가시 채널 관측을 이용한 지표면 반사도 산출 - 배경광학두께 보정의 효과 분석 -)

  • Kim, Mijin;Kim, Jhoon;Yoon, Jongmin
    • Korean Journal of Remote Sensing
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    • v.30 no.5
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    • pp.627-639
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    • 2014
  • Accurate correction of surface effect from back scattered solar radiance is one of key issue to retrieve aerosol information from satellite measurements. In this study, two different methods are applied to retrieve surface reflectance by using single visible channel measurement from meteorological imager onboard COMS. The first one is minimum reflectance method, which composes the minimum value among previously measured reflectances at each pixel over a certain search window length. This method assumes that the darkest pixel corresponds to the aerosol-free condition, and deduces surface reflectance by correcting atmospheric scattering from the measured visible reflectance. The second method, named as the "atmospheric correction method" in this study, estimates the result by correcting aerosol and atmospheric scattering with ground-based observation of aerosol optical properties. The purpose of this study is to investigate the retrieval accuracy of the widelyused minimum reflectance method. Also, the retrieval error caused by the loading of background aerosol is mainly estimated. The comparison between surface reflectances retrieved from the two methods shows good agreement with the correlation coefficient of 0.87. However, the results from the minimum reflectance method are slightly overestimated than the values from the atmospheric correction method when surface reflectance is lower than 0.2. The average difference between the two results is 0.012 without the background aerosol correction. By considering the background aerosol effect, however, the difference is reduced to 0.010.

Interpretation of Migration of Radionuclides in a Rock Fracture Using a Particle Tracking Method (입자추적법을 사용한 암반균열에서 핵종이동 해석)

  • Chung Kyun Park;Pil Soo Hahn;Douglas J. Drew
    • Nuclear Engineering and Technology
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    • v.27 no.2
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    • pp.176-188
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    • 1995
  • A particle tracking scheme was developed in order to model radionuclide transport through a tortuous flow Held in a rock fracture. The particle tacking method may be used effectively in a heterogeneous flow field such as rock fracture. The parallel plate representation of the single fracture fails to recognize the spatial heterogeneity in the fracture aperture and thus seems inadequate in describing fluid movement through a real fracture. The heterogeneous flow field une modeled by a variable aperture channel model after characterizing aperture distribution by a hydraulic test. To support the validation of radionuclide transport models, a radionuclide migration experiment was performed in a natural fracture of granite. $^3$$H_2O$ and $^{131}$ I are used as tracers. Simulated results were in agreement with experimental result and therefore support the validity of the transport model. Residence time distributions display multipeak curves caused by the fast arrival of solutes traveling along preferential fracture channels and by the much slower arrival of solutes following tortous routes through the fracture. Results from the modelling of the transport of nonsorbing tracer through the fracture show that diffusion into the interconnected pore space in the rock mass has a significant effect on retardation.

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Gradation and Transport Characteristics of Bed Materials in Pool-Riffle Sequence in the Gap Stream, Korea (갑천의 웅덩이-여울 연속구조에서 하상토의 입도 및 이동 특성)

  • Choi, Sung-Uk;Bae, Hye-Deuk
    • Journal of Korea Water Resources Association
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    • v.44 no.1
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    • pp.65-72
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    • 2011
  • Natural streams meander, forming pools at the outer part of bend and riffles at the crossing. Pools are deep at a lower flow velocity, and riffles are shallow at a higher flow velocity. Attentions are being paid to pool-riffle sequences in meandering streams because pool-riffle sequences tend to increase biodiversity of the stream ecosystem. This study investigates the characteristics of distribution of bed sediment particles in the upstream reach of the Gap Stream, which is a tributary of the Geum River in Korea. The upstream part of the Gap Stream, the study reach, is a gravel-bed stream, showing a pool and three riffles due to meandering. The reach also includes pools at the upstream and downstream parts of the weir. The characteristics of bed sediment particles sampled at the wetland and in the side channel are studied, revealing that the median particle diameter in the riffle is about four times larger than that in the pool. In addition, flow simulations are carried out for ordinary discharge and design flood, and such parameters important to sediment transport as velocity, shear stress, dimensionless shear stress (or Shields number), and dimensionless shear velocity are provided to see the mobility of sediment particles in the pool-riffle sequence.

Development of Continuous Rainfall-Runoff Model for Flood Forecasting on the Large-Scale Basin (대유역 홍수예측을 위한 연속형 강우-유출모형 개발)

  • Bae, Deg-Hyo;Lee, Byong-Ju
    • Journal of Korea Water Resources Association
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    • v.44 no.1
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    • pp.51-64
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    • 2011
  • The objective of this study is to develop a continuous rainfall-runoff model for flood prediction on a large-scale basin. For this study, the hourly surface runoff estimation method based on the variable retention parameter and runoff curve number is developed. This model is composed that the soil moisture to continuous rainfall can be simulated with applying the hydrologic components to the continuous equation for soil moisture. The runoff can be simulated by linking the hydrologic components with the storage function model continuously. The runoff simulation to large basins can be performed by using channel storage function model. Nakdong river basin is selected as the study area. The model accuracy is evaluated at the 8 measurement sites during flood season in 2006 (calibration period) and 2007~2008 (verification period). The calibrated model simulations are well fitted to the observations. Nash and Sutcliffe model efficiencies in the calibration and verification periods exist in the range of 0.81 to 0.95 and 0.70 to 0.94, respectively. The behavior of soil moisture depending on the rainfall and the annual loadings of simulated hydrologic components are rational. From this results, continuous rainfall-runoff model developed in this study can be used to predict the discharge on large basins.

Application of exponential bandwidth harmony search with centralized global search for advanced nonlinear Muskingum model incorporating lateral flow (Advanced nonlinear Muskingum model incorporating lateral flow를 위한 exponential bandwidth harmony search with centralized global search의 적용)

  • Kim, Young Nam;Lee, Eui Hoon
    • Journal of Korea Water Resources Association
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    • v.53 no.8
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    • pp.597-604
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    • 2020
  • Muskingum, a hydrologic channel flood routing, is a method of predicting outflow by using the relationship between inflow, outflow, and storage. As many studies for Muskingum model were suggested, parameters were gradually increased and the calculation process was complicated by many parameters. To solve this problem, an optimization algorithm was applied to the parameter estimation of Muskingum model. This study applied the Advanced Nonlinear Muskingum Model considering continuous flow (ANLMM-L) to Wilson flood data and Sutculer flood data and compared results of the Linear Nonsingum Model incorporating Lateral flow (LMM-L), and Kinematic Wave Model (KWM). The Sum of Squares (SSQ) was used as an index for comparing simulated and observed results. Exponential Bandwidth Harmony Search with Centralized Global Search (EBHS-CGS) was applied to the parameter estimation of ANLMM-L. In Wilson flood data, ANLMM-L showed more accurate results than LMM-L. In the Sutculer flood data, ANLMM-L showed better results than KWM, but SSQ was larger than in the case of Wilson flood data because the flow rate of Sutculer flood data is large. EBHS-CGS could be appplied to be appplicable to various water resources engineering problems as well as Muskingum flood routing in this study.

Analysis of Density Current in the Tidal River (감조하천(感潮河川)의 하구(河口) 밀도류해석(密度流解析))

  • Suh, Seung Duk;Park, Sung Bae
    • Current Research on Agriculture and Life Sciences
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    • v.4
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    • pp.70-76
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    • 1986
  • The purpose of this study is to offer the basic data of the tidal river development program by grasping the diffusion between the high density-sea water and the low density-fresh water in the tidal river. The tidal range of Hyungsan river which flows at Youngil bay in Pohang was selected to analysis the phenomenon of density current. The results obtained are as follows ; The tide of Youngil bay was one time a day, 0.104m in high tide difference and 0.085m in mean tidy difference. The change of sea level by tide was negligible. The volume of reserved water by sea water was $2,700,000m^3$ and available water of irrigation was $1,200,000m^3$ that salt density is below $750{\mu}{\mho}/cm$ out of total volume. Salt intrusion phenomenon by density current was a little water level change, however, it become a salt wedge type by the much salt invasion during the spring tide and it makes a well-mixed type by the retreating salt wedge during the neap tide. As long as there were some density differences between sea water and fresh water, net upstream flow was existed along the bottom of water way from the estuary to the upstream channel.

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Case Study on the Distribution of Disaster Risk Information in China (중국의 재난위험 정보유통에 관한 사례 연구)

  • Choi, Choong-Ik;Li, Cheng
    • Journal of Distribution Science
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    • v.14 no.4
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    • pp.55-66
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    • 2016
  • Purpose - This article aims to explore the characteristics of disaster risk distribution information in China. Also, this research attempts to analyze the findings of risk communication using case study in chronological order in terms of social amplification of risk. To achieve the purpose, the paper reviews the trends and issues of risk communication in China, with an emphasis on examining earthquakes by a chronological approach. In these regards, we hope that some relevant findings from this empirical study with cases will be able to enhance national risk communication and provide implications in Korea as well. Research design, data, and methodology - The conceptual framework of this study is theoretically based on the risk amplification model, which describes signals about risk transmitted and processed by individuals and social groups. The social amplification of risk also reflects the interactions of social groups about disaster-related risk issues, which are potential amplifiers or attenuators of communication signals. The key concept of social amplification implies that the risks pertaining to natural disasters interact with social, psychological, institutional, and cultural processes in ways that can affect public perceptions of risk. SMCRE Model is methodologically employed to examine risk communication history of China with the focus on natural disaster. Four earthquakes are selected to figure out the chronological characteristics of risk communication since 1970s. He bei Tang Shan earthquake is selected as an example disaster before 1990's, while the earthquake in Yun Nan Jiang is explored for the case study of 1990's. The earthquake in Si Chuan Wen Chuan is also examined as a example disaster of 2000's. The recent earthquake in Si Chuan Ya An Lu Shan is selected as a case of 2010s. Results - SMCRE model in this case study is operationally defined as a methodology and applied to the four earthquakes occurred in China. SMCRE model describes the exchange of risk information and is also applied to all forms of communication between stake holders. Each factor of risk communication includes source, message, channel, receiver and effect. It is notable that a big progress has been made on disaster risk communication in China for the past 40 years. We also found that highly developed information technology has enabled Chinese society to better cope with natural disaster, leading to enhanced disaster risk communication. It is mainly found from case study that the disaster risk communication of China has been involved with political situation, which derived from the change of government for the past 40 years. Conclusion - From this historical research, it can be inferred that the policies and politics of Chinese leaders have had a more critical role to play in the process of source of risk communication than those of any other countries. The results of this paper also support that the effective risk communication involves not only the improved reliability of local government as a key factor of disaster risk communication, but also is accompanied by international cooperation for substantial collaboration with stake holders.