• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.5
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• pp.182-189
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• 2002

This paper presents a framework of hybrid dynamic control systems for the motion control of wheeled mobile robot systems with nonholonomic constraints. The hybrid control system has the 3-layered hierarchical structure: digital automata for the higher process, mobile robot system for the lower process, and the interface as the interaction process between the continuous dynamics and the discrete dynamics. In the hybrid control architecture of mobile robot, the continuous dynamics of mobile robots are modeled by the switched systems. The abstract model and digital automata for the motion control are developed. In high level, the discrete states are defined by using the sensor-based search windows and the reference motions of a mobile robot in low level are specified in the abstracted motions. The mobile robots can perform both the motion planning and autonomous maneuvering with obstacle avoidance in indoor navigation problem. Simulation and experimental results show that hybrid system approach is an effective method for the autonomous maneuvering in indoor environments

• Journal of Environmental Science International
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• v.22 no.8
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• pp.965-977
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• 2013

Reliable long-term streamflow forecasting is invaluable for water resource planning and management which allocates water supply according to the demand of water users. It is necessary to get probabilistic forecasts to establish risk-based reservoir operation policies. Probabilistic forecasts may be useful for the users who assess and manage risks according to decision-making responding forecasting results. Probabilistic forecasting of seasonal inflow to Andong dam is performed and assessed using selected predictors from sea surface temperature and 500 hPa geopotential height data. Categorical probability forecast by Piechota's method and logistic regression analysis, and probability forecast by conditional probability density function are used to forecast seasonal inflow. Kernel density function is used in categorical probability forecast by Piechota's method and probability forecast by conditional probability density function. The results of categorical probability forecasts are assessed by Brier skill score. The assessment reveals that the categorical probability forecasts are better than the reference forecasts. The results of forecasts using conditional probability density function are assessed by qualitative approach and transformed categorical probability forecasts. The assessment of the forecasts which are transformed to categorical probability forecasts shows that the results of the forecasts by conditional probability density function are much better than those of the forecasts by Piechota's method and logistic regression analysis except for winter season data.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.953-963
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• 2013

Reliable long-term streamflow forecasting is invaluable for water resource planning and management which allocates water supply according to the demand of water users. Forecasting of seasonal inflow to Andong dam is performed and assessed using statistical methods based on hydrometeorological data. Predictors which is used to forecast seasonal inflow to Andong dam are selected from southern oscillation index, sea surface temperature, and 500 hPa geopotential height data in northern hemisphere. Predictors are selected by the following procedure. Primary predictors sets are obtained, and then final predictors are determined from the sets. The primary predictor sets for each season are identified using cross correlation and mutual information. The final predictors are identified using partial cross correlation and partial mutual information. In each season, there are three selected predictors. The values are determined using bootstrapping technique considering a specific significance level for predictor selection. Seasonal inflow forecasting is performed by multiple linear regression analysis using the selected predictors for each season, and the results of forecast using cross validation are assessed. Multiple linear regression analysis is performed using SAS. The results of multiple linear regression analysis are assessed by mean squared error and mean absolute error. And contingency table is established and assessed by Heidke skill score. The assessment reveals that the forecasts by multiple linear regression analysis are better than the reference forecasts.

• Korean Institute of Interior Design Journal
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• v.22 no.1
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• pp.299-306
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• 2013

While artists and architects both recognize the importance of well-designed exhibition spaces, they have rarely shared, through direct and open communication, their thoughts on what constitutes an ideal architectural context for art. Remy Zaugg's text offers a rare and valuable insight on artists' conception of an ideal space for art, and his words and diagrams have directly influenced some of the successful architectural projects for art in the recent past. By analyzing the original content of Zaugg's writings, and highlighting Zaugg's key design elements from three sample projects, all of which mention Zaugg's text as a direct reference, we can compile a list of core design elements for constructing an ideal space for art. Three museums closely incorporated all but two of Zaugg's seven core planning elements, and the remaining two recommendations on the luminous ceiling and gallery distribuition were more subjectively interpreted. These deviant components in turn become unique features to each project, suggesting proper areas of intervention for architects as authors.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1951-1956
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• 2019

As a part of the preliminary decommissioning plan of KEPCO-NF fuel fabrication facility, DCGLs of three target radionuclides, ²³⁴U, ²³⁵U, and ²³⁸U, were derived using RESRAD-BUILD code and contaminated areas of the facility were classified based on contamination levels from the derived DCGLs. From code simulations, one-room modeling results showed that the grinding room in building #2 was the most restrictive (DCGL_gross = 10493.01 Bq/㎡). The DCGL_gross results in contaminated areas from one-room modeling were slightly more conservative than three-room modeling. Prior to the code simulation, field survey and measurements conducted by each survey unit. For a conservative approach, the most restrictive DCGL_gross in each survey unit was taken as a reference to classify the contaminated areas of the facility. Accordingly, seven rooms and 37 rooms in the nuclear-fuel buildings were classified as Class 1 and Class 2, respectively. As expected, fuel material handling and processing rooms such as the grinding room, sintering room, compressing room, and powder collecting room were included in the Class 1 area.

• Industrial Engineering and Management Systems
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• v.13 no.2
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• pp.203-209
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• 2014

This research designed and implemented a supply chain risk management platform and applied it to a case study of reduced-fat Lanna pork sausage as a new product development project. The proposed framework has three stages: risk identification, risk assessment, and risk mitigation. Seventeen risk agents with 17 risk events were identified based on SWOT analysis and the Porter Five Forces concept through the process of planning, sourcing, making and delivering, partially captured from the supply chain operations reference model in the first stage. In the second stage, an house of risk (HOR) framework was applied to present the impacts of each risk agent. In the third stage, eight risk agents with high impact were selected to design 21 preventive actions. Finally, three preventive actions with the highest effectiveness to difficulty ratio scores-'sales evaluation of familiar products', 'increasing distribution channels and promotions to improve sales', and 'work flow improvement for work safety'-were then recommended for this new product development.

• Journal of Information Management
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• v.40 no.1
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• pp.1-27
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• 2009

The study investigated the indicators for information service system performance measurement through the review on the related literatures, and developed 16 indicators for the performance measurement in 4 areas of library visit, lending, reference service and user instruction, and electronic service. And then with the indicators, the study surveyed 6 academic libraries including each 2 of large, middle, and small sized academic libraries. Based on the survey results, the study made a proposal for the application of performance indicator and the improvement of information service system performance.

• Korea journal of population studies
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• v.11 no.1
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• pp.185-196
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• 1988

This study considers inter-jurisdictional fiscal externalities between a central city and suburbs, rigorously examines. and empirically tests the suburban-exploitation-of-central-cities hypothesis. Using micro-migra4ion data, house-holds 'intra-metropolitan migration between 1985 and 1990 Is examined based on a random utility model. It is found that efficient population distribution between a central city and suburbs can be achieved when local government stake into account inter-jurisdictional externalities. External aids from the federal and state governments should be given to public services such as education, welfare, health, and employee retirement services, if they intend to arrest central city decline. Regional tax sharifs can be another way of dealing with these externalities.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.6
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• pp.31-37
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• 2018

With the progress of national policy researches on the modular construction, many studies have been conducted regarding the standardization of interior building materials. However, studies on the standardization of exterior building materials are still insufficient, and there are no dedicated exterior materials for modular construction. In this regard, this study investigated the necessary of standardization through the analysis on 7 kinds of exterior materials used in general buildings and exterior building materials applied to modular apartment houses in order to establish design criteria for the standardization of dedicated modular exterior materials. Based on the analysis results, assembly reference plane in conjunction with inside dimensions was set, and panelizing standardized in five parts was proposed to solve the problem of low exterior material standardization rate. It also proposed elastic gasket and steel bracket details that can compensate for the fabrication errors of unit boxes and construction errors in stacking.

• Journal of Digital Contents Society
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• v.12 no.1
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• pp.95-105
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• 2011

It has become commonplace to use web-based business process systems in a variety of fields, and electronic litigation is not an exception. In electronic procedures where court records are at the core of the system, the electronic document architecture should be designed in a way that electronic documents are safely circulated and utilized on the web with a consideration of the authentication of records, particularity of cases and document security such as prevention of forgery or falsification. Based on a study of electronic formats suitable for court records, the Extensible Markup Language (XMP) for management of special case information and security requirements for circulation of electronic documents, this paper suggests an adequate architecture for electronic documents designed for electronic litigation involving constitutional matters and looks into cases where such architectures are applied. The studies in this paper will serve as a useful reference for those planning to realize web-based business process that enables exchanges of electronic documents.