• Horticultural Science & Technology
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• v.33 no.6
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• pp.854-859
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• 2015

This experiment was performed to develop a model for nutrition ion concentration and EC in regard to change in pH from 4.0 to 8.0 in nutrient solution. The pH changes according to the variation of $HPO_4{^{-2}}$ and $H_2PO_4{^-}$ in the nutrient solution while variation of EC increased from pH 4.0 to 5.0, stabilized from pH 5.0 to 7.0 and increased again from pH 7.0 to 8.0. For the variance of major elements in the nutrient solution, K, Ca, N and P increased while pH was higher, especially the variables for K and P were increased largely. On the other hand, variables of Mg and S were stable. Based on analysis of the ion balance model of nutrient solution, the cation increased than anion over rising the variation of pH while balance point of ion moved from a-side to d-side. In addition, the imbalance increased while it moved away from the EC centerline as variance of pH increased. It was larger than effect of EC variance to correction values of equivalence ratios of K and Ca about variation of $HPO_4{^{-2}}$ and $H_2PO_4{^-}$ while as variance of pH increased, K decreased but Ca increased. These showed the result that variance of pH about correction values of equivalence ratios of K and Ca gave a second-degree polynomial model rating of 0.97. Through this research, it was identified the pH variable model about variance among pH, ion and EC according to gradient of phosphate.

• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.781-795
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• 2008

This paper focuses on effects that IPTV will have on domestic broadcasting market in the point of view of customers. The purpose of the paper is to present the future landscape of competitive media market when IPTV is launched, and to research how IPTV will have impact on terrestrial broadcasting, cable TV and satellite broadcasting industry. The paper integrates two known theories, such as the niche-gratification model and the value-expectancy model, to analyze competitive media market. The value expected model makes it possible to overcome the weakness of the niche-gratification model and to forecast competitiveness more accurately. According to this research, competitive power will be in the order of Cable TV, IPTV, and satellite broadcasting. Terrestrial broadcasting does not show strong competitive relationships with others statistically. As a result, Cable TV will be the most competitive medium in the future. IPTV will be stuck in the middle and can rapidly substitute for existing broadcasting services. While IPTV will severely threaten the satellite broadcasting company which has a relatively small number of subscribers, cable TV will be in a superior position to IPTV.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.474-481
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• 2007

With population growth, industrialization, and urbanization within the watershed, the hydrologic response changed dramatically, resulting in increases in peak flow with lesser time to peak and total runoff with shortened time of concentration. Infiltration is directly affected by initial soil moisture condition, which is a key element to determine runoff. Influence of the initial soil moisture condition on hydrograph analysis should be evaluated to assess land use change impacts on runoff and non-point source pollution characteristics. The Long-Term Hydrologic Impact Assessment (L-THIA) model has been widely used for the estimation of the direct runoff worldwide. The L-THIA model was applied to the Little Eagle Creek (LEC) watershed and Its estimated direct runoff values were compared with the BFLOW filtered direct runoff values by other researchers. The $R^2$ value Was 0.68 and the Nash-Sutcliffe coefficient value was 0.64. Also, the L-THIA estimates were compared with those separated using optimized $BFI_{max}$ value for the Eckhardt filter. The $R^2$ value and the Nash-Sutcliffe coefficient value were 0.66 and 0.63, respectively. Although these higher statistics could indicate that the L-THIA model is good in estimating the direct runoff reasonably well, the Antecedent Moisture Condition (AMC) was not adjusted in that study, which might be responsible for mismatches in peak flow between the L-THIA estimated and the measured peak values. In this study, the L-THIA model was run with AMC adjustment for direct runoff estimation. The $R^2$ value was 0.80 and the Nash-Sutcliffe coefficient value was 0.78 for the comparison of L-THIA simulated direct runoff with the filtered direct runoff. However there was 42.44% differences in the L-THIA estimated direct runoff and filtered direct runoff. This can be explained in that about 80% of the simulation period is classified as 'AMC I' condition, which caused lower CN values and lower direct runoff estimation. Thus, the coefficients of the equation to adjust CN II to CN I and CN III depending on AMC condition were modified to minimize adjustments impacts on runoff estimation. The $R^2$ and the Nash-Sutcliffe coefficient values increase, 0.80 and 0.80 respectively. The difference in the estimated and filtered direct runoff decreased from 42.44% to 7.99%. The results obtained in this study indicate the AMC needs to be considered for accurate direct runoff estimation using the L-THIA model. Also, more researches are needed for realistic adjustment of the AMC in the L-THIA model.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.38-46
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• 2021

In the era of the 4th Industrial Revolution, the interest in autonomous ship technology is increasing as high-tech technologies are being increasingly utilized throughout the industry. Therefore, we conducted a basic study on autonomous ships. In particular, a passenger ship model was produced and an autonomous navigation system was established by applying the ardupilot used for drones. The possibility of automatic control of the autonomous ship operations was confirmed by executing various voyage plans using the built model ship. In the performance test for maintaining the course the model ship could not follow the designated course straight and sailed up to 5.4 m away from the course while navigating in a zigzag (S-shape); however, after the parameters were modified, the deviation distance was reduced to a maximum of 1.8 m. In the turning performance test, the maximum diameter of the turning sphere was found to be approximately 9.3 m, but no significant change could be confirmed even after the parameters were modified. However, the results of our tests on slowing down the ship before arriving at the WP confirmed that the diameter of the turning sphere was reduced to a maximum of approximately 3.2 m. In order to evaluate the stopping performance, the last scheduled stopping position of all experiments was compared with the actual stopping position of the model ship and it was confirmed that the model ship stopped at a point at least 0.4 m and a maximum of 6.2 m away from the stopping position. In the future, improvement of course stability, turning performance, and stopping performance is required through modification and supplementation of various parameters. Moreover, a study on automatic berthing of the model ship through automatic control is planned.

• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.279-295
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• 2021

The purpose of this study was to investigate the effect of Character-centered instruction model on pre-service science teachers' awareness of both character education and character education in science education. First of all, pre-questionnaires about the sixteen pre-service science teachers' awareness of character education and character education in science education were asked. Through the lectures during a semester, they received an education about CoProC(Collaborative Problem-Solving for Character competence) model using Character-centered instruction model and character education. After the implementation, their changes of awareness were inspected through post-questionnaires. As a result of the study, it was revealed that general pre-service science teachers' pre-awareness of character education was mostly negative. The pre-service science teachers were more aware of character education in science classes than general character education. Even that, there seemed to be a greater tendency to think in connection with specific content and subject matter and character education rather than developing competencies due to the nature of the science subject itself. However, the experiences of the CoProC model changed their perception about character into a competent point of view, and thus influenced the change in their perception of character education. Therefore, education on character education methods for pre-service science teachers at teacher training institutions will increase their expertise in character education and help establish effective character education in school in the long term.

• Asia pacific journal of information systems
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• v.23 no.2
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• pp.21-39
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• 2013

As the utilization of information technology and the turbulence of technological change increase in organizations, the adoption of IT outsourcing also grows to manage IT resource more effectively and efficiently. In this new way of IT management technique, service level management(SLM) process becomes critical to derive success from the outsourcing in the view of end users in organization. Even though much of the research on service level management or agreement have been done during last decades, the performance of the service level management process have not been evaluated in terms of final objectives of the management efforts or success from the view of end-users. This study explores the relationship between SLM maturity and IT outsourcing success from the users' point of view by a analytical case study in four client organizations under an IT outsourcing vendor, which is a member company of a major Korean conglomerate. For setting up a model for the analysis, previous researches on service level management process maturity and information systems success are reviewed. In particular, information systems success from users' point of view are reviewed based the DeLone and McLean's study, which is argued and accepted as a comprehensively tested model of information systems success currently. The model proposed in this study argues that SLM process maturity influences information systems success, which is evaluated in terms of information quality, systems quality, service quality, and net effect proposed by DeLone and McLean. SLM process maturity can be measured in planning process, implementation process and operation and evaluation process. Instruments for measuring the factors in the proposed constructs of information systems success and SL management process maturity were collected from previous researches and evaluated for securing reliability and validity, utilizing appropriate statistical methods and pilot tests before exploring the case study. Four cases from four different companies under one vendor company were utilized for the analysis. All of the cases had been contracted in SLA(Service Level Agreement) and had implemented ITIL(IT Infrastructure Library), Six Sigma and BSC(Balanced Scored Card) methods since last several years, which means that all the client organizations pursued concerted efforts to acquire quality services from IT outsourcing from the organization and users' point of view. For comparing the differences among the four organizations in IT out-sourcing sucess, T-test and non-parametric analysis have been applied on the data set collected from the organization using survey instruments. The process maturities of planning and implementation phases of SLM are found not to influence on any dimensions of information systems success from users' point of view. It was found that the SLM maturity in the phase of operations and evaluation could influence systems quality only from users' view. This result seems to be quite against the arguments in IT outsourcing practices in the fields, which emphasize usually the importance of planning and implementation processes upfront in IT outsourcing projects. According to after-the-fact observation by an expert in an organization participating in the study, their needs and motivations for outsourcing contracts had been quite familiar already to the vendors as long-term partners under a same conglomerate, so that the maturity in the phases of planning and implementation seems not to be differentiating factors for the success of IT outsourcing. This study will be the foundation for the future research in the area of IT outsourcing management and success, in particular in the service level management. And also, it could guide managers in practice in IT outsourcing management to focus on service level management process in operation and evaluation stage especially for long-term outsourcing contracts under very unique context like Korean IT outsourcing projects. This study has some limitations in generalization because the sample size is small and the context itself is confined in an unique environment. For future exploration, survey based research could be designed and implemented.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.2
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• pp.171-181
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• 2011

Recently, many studies have been attempted to save the cost of production and to build the ocean energy power generating system. The low-reflection structure with the wall-typed curtain which has a wave power generation system of OWC is known as the most effective energy conversion system. A three-dimensional numerical model was used to understand the characteristics of velocity of flows about compressed air and to estimate the pressure acting on the low-reflection structure due to the short-period waves. The three-dimensional numerical wave flume which is the model for the immiscible two-phase flow was applied in interpretation for this. The numerical simulation showed well about the changes in velocity of compressed air and the characteristics of pressure according to the change in the wave height and depth of the curtain wall. Additionally, the results found that there was the point of the maximum velocity of the compressed air when the reflection coefficient is at its lowest point.

• Cartoon and Animation Studies
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• s.17
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• pp.163-173
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• 2009

The reactivation for Art & Culture Content Space in Gangwon province need new turning point according to new approach with internal and external change. That should be established in sustainable possibility model with preexisted natural advantage instead of economical depression and global warming of in these days. That is not a choice to get a successful construction of art & culture content space in Gangwon province. Throughout of reactivation of art & culture content space in Gangwon province, this proposal should go on with diversity of culture and concrete art & culture educational program absolutely to get a goal in regional economical success and social good influence. Already Yeongwol region had lots of art & cultural spaces and developmental strategy compared with other regions in decade. In these points, I choose this region and would like to research Yeongwol region in limit. Thus I would examine and study about art & culture content space in Yeongwol region. And I will concretely suggest that this proposal is composed with economical creating employment and incoming. The reactivation for Art &Culture Content Space in Yeongwol will build up social and cultural influences to this region to get a new modern cultural images and improvement of common life of regional people by and large. In the way of the process to globalization, this reactivation project for Art &Culture Content Space in Yeongwol should go on the base of regional culture background as a mean of glocalization paradigm strategically. Ahead of developing model for globalization in macroscopic view point, we have to research the demend of reginal situation of cultural content and build up its own strength points. Because Art & Culture Content Space in Yeongwol is the place of people in Yeongwol directly as itself. And managing plans of reactivation of art & culture content space in Yeongwol should build up with diversity of culture and environmental circumstances.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.35-40
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• 2011

While high-definition precipitation maps with a 270 m spatial resolution are available for South Korea, there is little information on geospatial availability of precipitation water for the famine - plagued North Korea. The restricted data access and sparse observations prohibit application of the widely used PRISM (Parameter-elevation Regressions on Independent Slopes Model) to North Korea for fine-resolution mapping of precipitation. A hybrid method which complements the PRISM grid with a sub-grid scale elevation function is suggested to estimate precipitation for remote areas with little data such as North Korea. The fine scale elevation - precipitation regressions for four sloping aspects were derived from 546 observation points in South Korea. A 'virtual' elevation surface at a 270 m grid spacing was generated by inverse distance weighed averaging of the station elevations of 78 KMA (Korea Meteorological Administration) synoptic stations. A 'real' elevation surface made up from both 78 synoptic and 468 automated weather stations (AWS) was also generated and subtracted from the virtual surface to get elevation difference at each point. The same procedure was done for monthly precipitation to get the precipitation difference at each point. A regression analysis was applied to derive the aspect - specific coefficient of precipitation change with a unit increase in elevation. The elevation difference between 'virtual' and 'real' surface was calculated for each 270m grid points across North Korea and the regression coefficients were applied to obtain the precipitation corrections for the PRISM grid. The correction terms are now added to the PRISM generated low resolution (~2.4 km) precipitation map to produce the 270 m high resolution map compatible with those available for South Korea. According to the final product, the spatial average precipitation for entire territory of North Korea is 1,196 mm for a climatological normal year (1971-2000) with standard deviation of 298 mm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2876-2882
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• 2015

The object of this study is to identify changes in air pollution in the maximum ground level concentration and the surrounding area when air pollution control facilities are improved in the thermal power plants. The effects of improved facilities are analyzed by comparing air quality after applying improved air pollution control facilities. For prediction of air quality, the change of wind field can be represented with movement of Puff and CALPUFF Model, air pollution diffusion models which can implement abnormal conditions. Major air pollutants of thermal power plants such as $SO_2$, $NO_2$, and $PM_{10}$ are selected as prediction items. That results show that improvement of air pollution control facilities is significantly effective in reduction of air pollution of $SO_2$ and $NO_2$ in the maximum ground level concentration and areas around of thermal power plants. In the case of $PM_{10}$, it is found that the effect of reduction in pollution is high in the maximum ground level concentration, but the effect of reduction in air pollution is somewhat low in the area around of the thermal power plant.