• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.103-113
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• 2015

Korean pines(Pinus koraiensis) are one of the major plantation species in the Republic of Korea and their natural habitats range from Japan and China to Siberia. The seed of Korean pines, pine nuts, are well know for good food reserves. Due to the global changes which drive the Korean peninsula into the semi-tropical climate, current plantations and natural habitats of Korean pines are faced with the change in the environmental conditions to some extent. To anticipate suitable sites for Korean pines in the future, the location of Korean pines were extracted from the 'Map of suitable trees on a site' that provides the map of suitable trees on a site considering tree species for timber and special uses, and then MaxEnt modelling was used for generating a prediction map on the basis of statistical analysis. As a result, the order of predicted suitable sites were Kangwon-do, Kyungsangbuk-do and Chungcheongbuk-do provinces and sites with high elevation within those provinces were considered most suitable in common. The prediction map of suitable sites for Korean pines presented that suitable sites in the future decreased by 72.2% by 2050's and almost disappeared with a decrease of 92.1% by 2070's on a nationwide scale. In relation to the major production regions of pine nuts in South Korea - Gapyung gun and Yangpyung gun, Kyunggi province and Hongcheon gun, Kangwon province, suitable sites within their areas were predicted to increase by 2050's but become extinct in South Korea by 2070's. To establish a long-term countermeasures against the improvement on forest productivity quality in terms of managing national food security, the result from this study can be considered as a firm basis of predicting plantation suitability. Also, it can be used to predict the changes in supply of forest products and thereby market values in accordance with climate change scenarios.

• Korean Business Review
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• v.11
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• pp.15-38
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• 1998

This study explores the evolution of technical innovation over time. It focuses on sectors of the information technology because this industry can be referred to as one of the most dynamic industries of all times. Following evolutionary theorists, we argue that technological change is gradual and that superior firms and technologies are reward by the' selection' environment. In the initial phase of the industry life cycle, technological change is expected to be radical and uncertainty is high. Over time a product or technology is likely to arise which stands out above all other products or technologies. These so-called 'basic designs' serve as sorts of 'technological guideposts' for further developments in the technology. Once a basic design established, technological progress tends to follow consistent paths or trajectories. The cumulative character of technological progress facilitates a rapid expansion of the boundaries of the technology until the natural limits of the technology are approached and technological progress slows down. Following ecological theories, supply-side developments in the industry are described on the basis of five different organizational types. On the basis of this pattern of market and technological evolution we came up with seven basic propositions.

• Korean Journal of Culture and Social Issue
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• v.9 no.1
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• pp.81-114
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• 2003

This study examines the basis and change of delinquent behavior among Korean adolescents. Theoretical framework was developed and qualitative analysis of delinquency behavior was examined. In order to understand the basis and change of juvenile delinquency, the influence of family environment, school environment and individual factors were investigated through cross-sectional and longitudinal studies. The results of the findings can be summarized into the following six main points: 1) two subcultures of adolescent functioning could be ascertained, 2) the decrease in social support and increase in moral disengagement were directly related to a rise in juvenile delinquency, 3) family disintegration contributed to juvenile delinquency, 4) peer influence help to raise juvenile delinquency, 5) schools were unable to give hope to those students who were not doing well in school and were ineffective in dealing with juvenile delinquents, and 6) the phenomenon of juvenile delinquency points to the importance of opening up the closed school system and closed society, allowing individual diversity and skills to be recognized.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.405-406
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• 2005

A theoretical investigation of the solid-phase mechanochemical synthesis of nano-sized target product on the basis of dilution of the initial powdered reagent mixture by another product of an exchange reaction is presented. On the basis of the proposed 3-mode particle size distribution in mechanically activated mixture, optimal molar ratios of the components in mixture are calculated, providing the occurrence of impact-friction contacts of reagent particles and excluding aggregation of the nanosized particles of the target reaction product. Derivation of kinetic equations for mechanochemical synthesis of nanoscale particles by the final product dilution method in the systems of exchange reactions is submitted. On the basis of obtained equations the necessary times of mechanical activation for complete course of mechanochemical reactions are designed. Kinetics of solid phase mechanosynthesis of nano-TlCl by dilution of initial (2NaCl + $Tl_2SO_4$) mixture with the exchange reaction product (diluent, $zNa_2SO_4$, $z=z^*=11.25$) was studied experimentally. Some peculiar features of the reaction mechanism were found. Parameters of the kinetic curve of nano-TlCl obtained experimentally were compared with those for the model reaction KBr + TlCl + zKCl = (z + 1) KCl + TlBr ($z=z_l^*=13.5$), and for the first time the value of mass transfer coefficient in a mechanochemical reactor with mobile milling balls was evaluated. Dynamics of the size change was followed for nanoparticle reaction product as a function of mechanical activation time.

• Journal of the Speleological Society of Korea
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• no.71
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• pp.5-11
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• 2006

A theoretical investigation of the solid phase mechanochemical synthesis of nano sized target product on the basis of dilution of the initial powdered reagent mixture by another product of an exchange reaction is presented. On the basis of the proposed 3 mode particle size distribution in mechanically activated mixture, optimal molar ratios of the components in mixture are calculated, providing the occurrence of impact friction contacts of reagent particles and excluding aggregation of the nanosized particles of the target reaction product. Derivation of kinetic equations for mechanochemical synthesis of nanoscale particles by the final product dilution method in the systems of exchange reactions is submitted. On the basis of obtained equations the necessary times of mechanical activation for complete course of mechanochemical reactions are designed. Kinetics of solid phase mechanosynthesis of nano TlCl by dilution of initial (2NaCl+$Tl_2SO_4$) mixture with the exchange reaction product (diluent,$zNa_2SO_4$, z=z*=11.25) was studied experimentally. Some peculiar features of the reaction mechanism were found. Parameters of the kinetic curve of nano TlCl obtained experimentally were compared with those for the model reaction KBr+TlCl+zKCl=(z+1) KCl+TlBr (z=z1*=13.5), and for the first time the value of mass transfer coefficient in a mechanochemical reactor with mobile milling balls was evaluated. Dynamics of the size change was followed for nanoparticle reaction product as a function of mechanical activation time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.8
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• pp.2851-2865
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• 2014

To improve the rate-distortion performance of distributed video compressive sensing (DVCS), the adaptive sparse basis and nonlocal similarity of video are proposed to jointly reconstruct the video signal in this paper. Due to the lack of motion information between frames and the appearance of some noises in the reference frames, the sparse dictionary, which is constructed using the examples directly extracted from the reference frames, has already not better obtained the sparse representation of the interpolated block. This paper proposes a method to construct the sparse dictionary. Firstly, the example-based data matrix is constructed by using the motion information between frames, and then the principle components analysis (PCA) is used to compute some significant principle components of data matrix. Finally, the sparse dictionary is constructed by these significant principle components. The merit of the proposed sparse dictionary is that it can not only adaptively change in terms of the spatial-temporal characteristics, but also has ability to suppress noises. Besides, considering that the sparse priors cannot preserve the edges and textures of video frames well, the nonlocal similarity regularization term has also been introduced into reconstruction model. Experimental results show that the proposed algorithm can improve the objective and subjective quality of video frame, and achieve the better rate-distortion performance of DVCS system at the cost of a certain computational complexity.

• Journal of the Korea Society of Computer and Information
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• v.4 no.2
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• pp.155-163
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• 1999

This study is intended to analyze what trend the EVA technique recently actively studied shows according to the financial structure of the firm. As a result of analysis, it was found that the firm with the entire sum of its capitals depleted showed the negative value in both the EVA on the basis of operating profit and the EVA on the basis of cash flow from 5 years before its capitals were depleted. Especially, its EVA showed the negative value more strongly than the cash flow accruing by business activity. In analyzing the EVA of the firm with more than 1,500% of the debt to equity ratio, its EVA also showed the negative value from 5 years ago. But the firm with the good financial structure of the debt to equity of less than 35% showed the positive value in the EVA on the basis of its cash flow from 5 years ago. As can be seen from this result, the fact is that the firm can survive only when it raises its EVA through its structural change(re-engineering) and business innovation. Therefore, firms need to seek to turn their business philosophy or policy into the promotion of business innovation and business management emphasizing technology in order to improve their EVA indicators.

• Journal of Sensor Science and Technology
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• v.25 no.6
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• pp.431-434
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• 2016

Currently, the radial basis function network (RBFN) and various other neural networks are employed to classify gases using chemical sensors arrays, and their performance is steadily improving. In particular, the identification performance of the RBFN algorithm is being improved by optimizing parameters such as the center, width, and weight, and improved algorithms such as the radial basis function network-stochastic gradient (RBFN-SG) and radial basis function network-normalized stochastic gradient (RBFN-NSG) have been announced. In this study, we optimized the number of centers, which is one of the parameters of the RBFN-NSG algorithm, and observed the change in the identification performance. For the experiment, repeated measurement data of 8 samples were used, and the elbow method was applied to determine the optimal number of centers for each sample of input data. The experiment was carried out in two cases(the only one center per sample and the optimal number of centers obtained by elbow method), and the experimental results were compared using the mean square error (MSE). From the results of the experiments, we observed that the case having an optimal number of centers, obtained using the elbow method, showed a better identification performance than that without any optimization.

• Journal of Korean Library and Information Science Society
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• v.25
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• pp.569-593
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• 1996

The purpose of this study is to synthesize the theoretical systems concerning the necessity, methods, contents, and institutions of the continuing education for academic reference librarians in Korea, and to present a direction after performing a survey research to the librarians and grasping the phenomena on the basis of the system. The necessity, participation, contents, and performing institutions of continuing education were examined in detail, and the correlations among the sub-groups divided by gender, age, academic level of study, career as a librarian were analyzed. Also the direction of continuing education for reference librarians was presented on the basis of the analysis. On the basis of the analyzed contents, the following three methods for an ideal form to the continuing education of the reference librarians were presented in this thesis. 1) It is desirable that the continuing educations are performed at a professionalized institutions such as a library and information science department in a college and an education center for librarians which offers the Certificates of Advanced Study(CAS) as a librarian. 2) It is necessary to develop the various types of educational program in which a working reference librarian may take more chances to study during vacation, weekends, or in the evening time. 3) It is necessary to develop the proper educational contents that reference librarians want, and to educate the librarians in order for them to keep pace with the change of times.

• Korean Journal of Remote Sensing
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• v.33 no.6_2
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• pp.1075-1087
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• 2017

In this study, we tried to utilize results of the change detection analysis for satellite images as the basis for updating the land cover map. The Sequential Spectral Change Vector Analysis ($S^2CVA$) was applied to multi-temporal multispectral satellite imagery in order to extract changed areas, efficiently. Especially, we minimized the false alarm rate of unsupervised change detection due to the seasonal variation using the direction information in $S^2CVA$. The binary image, which is the result of unsupervised change detection, was integrated with the existing land cover map using the zonal statistics. And then, object-based analysis was performed to determine the changed area. In the experiment using PlanetScope data and the land cover map of the Ministry of Environment, the change areas within the existing land cover map could be detected efficiently.