• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.4
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• pp.15-26
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• 2009

Bass diffusion model have played a central role in studying the diffusion of the new products since 1969, the year of publication of Bass model. Almost 750 publications based on the Bass diffusion model have explored extensions and applications. Extension models can be divided into two types. One is the model containing marketing-mix variables and the other is the model containing additional parameters. This paper presents another extension model of the latter type. Our model allows the time varying coefficients of innovation and imitation. Two pieces approximation of time varying coefficients is introduced and it's parameters are estimated based on NLS(Non-Linear Mean Square) method. Empirical studies are performed and the results show that our model is superior to the basic Bass model and the NUI(Non-Uniform Influence) model which is the well-known extension of the Bass model. The model developed in this paper is, also, transformed into the Bass model with the ready potential adopters in order to enhance the descriptive power.

• Korean Journal of Computational Design and Engineering
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• v.11 no.6
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• pp.393-402
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• 2006

The purpose of this study is to develop mechanisms of nD model-based design by the combination of 2D drawing standards and 3D building models from the current 2D and text-based design. The aim of this study can be archived by defining the 2D model extension definitions for the IFC model development and harmonizing existing 2D standards. The paper examines 1) 3D Representation of Building Element and Building Services element, and 2D Model extension of IFC2X.2, 2) Basic development of additional 2D element that should be added to IFC model, and 3) mapping method between current 2D standard and IFC2.X2. Following this approach, the interoperability problem between 3D model and 2D drawing can be solved and finally an extended data model could be developed.

• Journal of Agricultural Extension & Community Development
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• v.7 no.2
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• pp.295-306
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• 2000

The objectives of this paper were to review the difference between the analog and digital age, and to suggest new communication strategies for Agricultural Extension Service Centers in the digital age. Literature review and discussion on the information age and its supporting technologies, such as the Internet and other digital tools, has enabled communication to occur during time periods and in locations based upon individual needs. With increasing number of internet subscribers using email and the world wide web, the internet is now considered a new mass media for communication, and may soon consider such electronic connectivity as essential in agricultural extension services. Communication strategies in the future should recognize and adapt to the changing needs farmers and extension educators in the information age. Utilization of internet technology and digital tools in communication may attract and retain farmers and extension educators in the future, thus. some of new strategies for communication in agricultural extension services should include the following; 1) traditional linear model should be change into interactive model in communication. 2) Agricultural extension service should include creative role with diffusion process. 3) Agricultural extension service should establish new receiver paradigm and form new partnership with farmer.

• Journal of Korean Neurosurgical Society
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• v.47 no.6
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• pp.446-453
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• 2010

Objective : The purpose of this study was to analyze the biomechanical effects of three different constrained types of an artificial disc on the implanted and adjacent segments in the lumbar spine using a finite element model (FEM). Methods : The created intact model was validated by comparing the flexion-extension response without pre-load with the corresponding results obtained from the published experimental studies. The validated intact lumbar model was tested after implantation of three artificial discs at L4-5. Each implanted model was subjected to a combination of 400 N follower load and 5 Nm of flexion/extension moments. ABAQUS$^{TM}$ version 6.5 (ABAQUS Inc., Providence, RI, USA) and FEMAP version 8.20 (Electronic Data Systems Corp., Plano, TX, USA) were used for meshing and analysis of geometry of the intact and implanted models. Results : Under the flexion load, the intersegmental rotation angles of all the implanted models were similar to that of the intact model, but under the extension load, the values were greater than that of the intact model. The facet contact loads of three implanted models were greater than the loads observed with the intact model. Conclusion : Under the flexion load, three types of the implanted model at the L4-5 level showed the intersegmental rotation angle similar to the one measured with the intact model. Under the extension load, all of the artificial disc implanted models demonstrated an increased extension rotational angle at the operated level (L4-5), resulting in an increase under the facet contact load when compared with the adjacent segments. The increased facet load may lead to facet degeneration.

• Korean Journal of Computational Design and Engineering
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• v.11 no.6
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• pp.429-439
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• 2006

The purpose of this study is to support the integration from current 2D drawing-based design to future 3D model-based design. In this paper, an important theme is the combination between the STEP-based 2D drawing standards (i.e., AP202) and the IFC-based 3D building model standards. To achieve the purpose, two methodologies are proposed as follows: the development of IFC extension model for the 2D shape data representation by harmonizing ISO/STEP AP202; and the development of mapping solution between IFC 2D extension model and KOSDIC by constructing the exchange scenario for 2D shape data representation. It is expected that the proposed IFC2X2 2D extension model and mapping solution will offer the basis of development of the integrated standards model in AEC industry.

• Journal of Agricultural Extension & Community Development
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• v.4 no.1
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• pp.371-384
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• 1997

The objectives of this study were to investigate the present of agricultural extension education implemented in agricultural colleges since 1993 and to explore the development directions for strengthening the agricultural extension education in Korea. The Advanced Agricultural Management Program (AAMP), College of Agriculture & Life Sciences, Seoul National University is a rural adult education program for selected young farmers as a part of university extension education. The AAMP offers classes to farmers to improve their managerial skills in farming including high-technology agriculture, farm management, communication and information, and also offers various classes in the area of social, economic, and cultural affairs to improve leadership. Since the innovative AAMP started in March 1993 at the Seoul National University, 18 local national and private universities have adopted this model within six months to a year period. The AAMPs are integration of formal education with extension education, and expected develop understanding of the problems of rural areas and a strategic model for rural development. The programs are expected to contribute to develop human resources in agriculture and rural society, activate university extension, and lead the balanced development between urban and rural sectors in Korea.

• Korean journal of communication and information
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• v.61
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• pp.28-51
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• 2013

The present study analyzed the effects of brand extension on the existing parent brand by applying the media brand extension model which previous studies had suggested based on consumer based brand equity model. Based on previous studies, the present study constructed a research model in which pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived number of brand extensions, perceived fit between parent brand and brand extended channel, and brand extended channel evaluation are supposed to affect post-brand extension brand extension evaluation, and tested the media brand extension feedback effects model through structural equation modeling. The analysis results show that pre-brand extension parent brand evaluation, brand portfolio quality variance, perceived fit, and brand extended channel evaluation affect post-brand extension parent brand evaluation while the effect of perceived number of brand extensions is not significant.

• MALSORI
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• no.52
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• pp.133-144
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• 2004

The quality of narrowband speech can be enhanced by the bandwidth extension technology. This paper proposes a mixed excitation and an energy compensation method based on Gaussian Mixture Model (GMM). First, we employ the mixed excitation model having both periodic and aperiodic characteristics in frequency domain. We use a filter bank to extract the periodicity features from the filtered signals and model them based on GMM to estimate the mixed excitation. Second, we separate the acoustic space into the voiced and unvoiced parts of speech to compensate for the energy difference between narrowband speech and reconstructed highband, or lowband speech, more accurately. Objective and subjective evaluations show that the quality of wideband speech reconstructed by the proposed method is superior to that by the conventional bandwidth extension method.

• International Journal of Concrete Structures and Materials
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• v.19 no.1E
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• pp.25-32
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• 2007

The fracture energy evaluated from the previous experimental results can be simulated by using the modified singular fracture process zone (S-FPZ) model. The fracture model has two fracture properties of strain energy release rate for crack extension and crack close stress versus crack width relationship $f_{ccs}(w)$ for fracture process zone (FPZ) development. The $f_{ccs}(w)$ relationship is not sensitive to specimen geometry and crack velocity. The fracture energy rate in the FPZ increases linearly with crack extension until the FPZ is fully developed. The fracture criterion of the strain energy release rate depends on specimen geometry and crack velocity as a function of crack extension. The behaviors of micro-cracking, micro-crack localization and full development of the FPZ in concrete can be explained theoretically with the variation of strain energy release rate with crack extension.

• Journal of the Korean Institute of Educational Facilities
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• v.10 no.3
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• pp.5-13
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• 2003

This paper is a series of study for the development of rural elementary school facilities model applying to the regional characteristics. Therefore, main theme of this paper is to pile up and analysis of elementary school facilities data in Po Cheon through a series of actual survey and interview with teachers. The results are summarized as follows ; First of all, in case of Po Cheon, it needs to study for urban model type as well as rural elementary school facilities model type. Second, extension type of buildings has separated as three types-zigzag extension type, vertical & horizontal extension type, separate building type. But another characteristics, such as type of site plan, type of corridor and module of classroom unit, outdoor space and elevation design, are monotonous. Third. the results of this analysis show that it is desirable to locate houses for teachers within boundaries. Finally, the future paper needs to be studying more various module of classroom unit, extension type, space program, type of floor plan and site plan.