• Journal of the Semiconductor & Display Technology
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• v.8 no.1
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• pp.43-48
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• 2009

We have examined the problem of the number of quad-tree blocks that an n-dimensional rectangle will be decomposed into on the average. the contribution of this paper are both practical and theoretical. In this paper, we develops the overlapping multi-scale models and the region quad-tree models which is useful in computer graphics animation, image processing, pattern recognition and also for modeling three dimensional objects. These models, which represent something of a conceptual departure from other models developed for multi-scale framework were developed with the specific interest of producing smooth estimates.

• IE interfaces
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• v.19 no.1
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• pp.9-18
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• 2006

In this paper, we explore the ubiquitous system that provides new business opportunities in the context of digital convergence. Exploiting the value network of the proposed ubiquitous system, we analyze strategic market drivers that define the speed and direction of the evolution path for ubiquitous industries. Motivated by the dynamic growth of ubiquitous industry, we design a set of ubiquitous business models that pave the way for firms to identify profitable business cases. In addition, we analyze the evolution path of the proposed business model such that the model can be implemented in the life-cycle of ubiquitous industry. Futhermore, we develop a modeling framework for selecting a suitable business model and for evaluating the performance of the selected business model.

• Journal of Preventive Medicine and Public Health
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• v.56 no.4
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• pp.303-311
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• 2023

Traditional mediation analysis, which relies on linear regression models, has faced criticism due to its limited suitability for cases involving different types of variables and complex covariates, such as interactions. This can result in unclear definitions of direct and indirect effects. As an alternative, causal mediation analysis using the counterfactual framework has been introduced to provide clearer definitions of direct and indirect effects while allowing for more flexible modeling methods. However, the conceptual understanding of this approach based on the counterfactual framework remains challenging for applied researchers. To address this issue, the present article was written to highlight and illustrate the definitions of causal estimands, including controlled direct effect, natural direct effect, and natural indirect effect, based on the key concept of nested counterfactuals. Furthermore, we recommend using 2 R packages, 'medflex' and 'mediation', to perform causal mediation analysis and provide public health examples. The article also offers caveats and guidelines for accurate interpretation of the results.

• Journal of Korean Library and Information Science Society
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• v.48 no.4
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• pp.129-151
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• 2017

Information modeling that is broadly applied in digital archiving process privides conceptual process that can be used to guide the creation of descriptions for the objects of preservation. However, it has faced with the limitations on substantially applying to the creation of preservation metadata records. This research proposes the concept of Resource Cluster in order to address these problems and efficiently describe the objects of preservation during digital archiving process. It also constructed Preservation Description Framework (PDF) based on RDF in order to substantially manifest preservation descriptions. This framework combines the structure of OAIS Reference Model and Functional Requirements for Bibliographic Records (FRBR) and can be an alternative approach to the creation of preservation metadata in more efficient and effective ways.

• Journal of Information Technology Services
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• v.7 no.4
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• pp.45-60
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• 2008

Networked enterprise (NE) is an organization of independent companies that collaborate with each other temporary or permanently for accomplishing common goals. The USA and EU have been developing principal concepts, techniques, and solutions to enhance the competitiveness of traditional industries including small-and-medium enterprises (SMEs). In Korea, however, implementation as well as R&D of NE is very few, which we believe comes from lack of understanding on Its meaning and lack of effective information systems for it. This paper is to suggest an Enterprise Architecture (EA) framework or reference model of NE and an Information Technology Architecture (ITA) of NE. The EA framework will help stakeholder of NE (e,g., policy makers, members of NE, IT solution providers, and researchers) understand structural and behavioral characteristics of NE. The ITA will be used as a guideline of developing information systems for NE that is essential for spreading networked business models, The focus of this paper is not on logical-level design but on conceptual-level modeling of NE. As verification of the suggested framework and architecture is still required, so we'll apply them to various manifestations of NE, e.g., dynamic supply chain, vertical integration of extended enterprises, and P2P-style virtual enterprises.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.662-674
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• 2017

This paper describes the multidisciplinary design optimization (MDO) process of a tailless unmanned combat aerial vehicle (UCAV) using global variable fidelity aerodynamic analysis. The developed tailless UAV design framework combines multiple disciplines that are based on low-fidelity and empirical analysis methods. An automated high-fidelity aerodynamic analysis is efficiently integrated into the MDO framework. Global variable fidelity modeling algorithm manages the use of the high-fidelity analysis to enhance the overall accuracy of the MDO by providing the initial sampling of the design space with iterative refinement of the approximation model in the neighborhood of the optimum solution. A design formulation was established considering a specific aerodynamic, stability and control design features of a tailless aircraft configuration with a UCAV specific mission profile. Design optimization problems with low-fidelity and variable fidelity analyses were successfully solved. The objective function improvement is 14.5% and 15.9% with low and variable fidelity optimization respectively. Results also indicate that low-fidelity analysis overestimates the value of lift-to-drag ratio by 3-5%, while the variable fidelity results are equal to the high-fidelity analysis results by algorithm definition.

• Knowledge Management Research
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• v.7 no.2
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• pp.53-68
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• 2006

Knowledge has become an important resource for organization. The manufacturing industry is usually operated on the basis of business processes, and most workers are familiar with their own processes. The process-based approach, therefore, can provide an efficient way to capture and navigate knowledge. In this study, we focus on knowledge which may be missed during knowledge transfer among workers. For this, we propose a method for analyzing knowledge flow, which is passed among business processes. We propose a process-based knowledge management framework for analyzing knowledge flow, which employs a two-phase analysis: process analysis and knowledge flow analysis. A knowledge flow model, represented by Knowledge Flow Diagram, is proposed as a tool for representing knowledge. We formulate several semantics for knowledge flow modeling. We build the three-level schema: conceptual, logical, and physical in order to automate the knowledge model adaptive to knowledge management systems. The proposed approach is verified and illustrated through a case study on the manufacturing process of A Company.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1564-1569
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• 1991

In this paper we describe Flexible Manufacturing Systems (FMS) using Petri nets, since Petri nets provide a powerful tool for modeling dynamical behavior of discrete concurrent processes. We deal with off-Line and on-Line rule-based scheduling of FMS. The role of the rule-base is to generate appropriate priority rule for resolving conflicts, that is, for selecting one of enabled transitions to be fired in a conflict set of the Petri nets. This corresponds to select a part type to be processed in the FMS. Towards developing more Intelligent Manufacturing Systems (IMS) we propose a conceptual framework of a futuristic intelligent scheduling system.

• Journal of Information Technology Applications and Management
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• v.12 no.1
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• pp.35-48
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• 2005

An architectural framework is developed for integrating geospatial and temporal data with relational information from which a spatio-temporal data warehouse (STDW) system is built. In order to implement the STDW, a generic conceptual model was designed that accommodated six dimensions: spatial (map object), temporal (time), agent (contractor), management (e.g. planting) and tree species (specific species) that addressed the 'where', 'when', 'who', 'what', 'why' and 'how' (5W1H) of the STDW information, respectively. A formal algebraic notation was developed based on a triplet schema that corresponded with spatial, temporal, and relational data type objects. Spatial object structures and spatial operators (spatial selection, spatial projection, and spatial join) were defined and incorporated along with other database operators having interfaces via the generic model.

• Educational Technology International
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• v.9 no.2
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• pp.79-95
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• 2008

This paper aims to investigate modeling scripts based on the mode of group interaction in a computer-supported collaborative learning environment. Based on a literature review, this paper assumes that group interaction and its mode would have strong influence on the online collaborative learning process, and furthermore lead learners to create and share significant knowledge within a group. This paper deals with two different modes of group interaction- distributed and shared interaction. Distributed interaction depends on the external representation of individual knowledge, while shared interaction is concerned with sharing knowledge in group action. In order to facilitate these group interactions, this paper emphasizes the utilization of appropriate CSCL scripts, and then proposes the conceptual framework of CSCL scripts which integrate the existing scripts such as implicit, explicit, internal and external scripts. By means of the model regarding CSCL scripts based on the mode of group interaction, the implications for research on the design of CSCL scripts are explored.