• Journal of the Korean Statistical Society
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• v.32 no.1
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• pp.1-10
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• 2003

We consider obtaining graphical summaries of uncertainty in estimates of parameters in nonlinear models. A nonlinear constrained optimization algorithm is developed for likelihood based confidence intervals for the functions of parameters in the model The results are applied to the problem of finding significance levels in nonlinear models.

• Journal of Korea Multimedia Society
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• v.3 no.3
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• pp.290-297
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• 2000

For verifying consistency and completeness of some UML diagrams as a representative of the graphic notations for object-oriented designs, we first give an analysis of some UML diagrams and apply simple ER model to the UML diagrams. Next, we formally define this graphical representation as a set of sets and a set of functions. According to the semantics of these functions, we derive a set of rules to assure the consistency and completeness of this graphical representation. These rules will be included with a CASE tool, which possesses both the diagramming facility and the consistency and completeness checking capability.

• Journal of Korean Society for Quality Management
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• v.24 no.4
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• pp.156-167
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• 1996

D-optimality is used often in design augmentation of mixture experiments. Although such alphabetic criteria provide a valuable foundation for generating designs, they often fail to convey the true nature of the design's support of the fitted model in terms of prediction variance over a region of interest. Thus, a graphical method is proposed to evaluate augmented designs in mixture experiments. This method can be used to evaluate the effect of missing observation and outlier in mixture experiments.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.519-526
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• 1994

In the large and multifunctional engineering system, the heterogeneous computer system situation is inevitable. Accordingly a lot of integration efforts are being made to comply with the industrial requirement of productivity. In this paper, a practical concept of integration is introduced through the development of a prototype system for ship outfitting design which is a typical example of large/multi-functional application system. On the development of the prototype system, three points are considered as a practical concept-which are integration of database, integration of application programs, and system-user interface. The relation model based commercial database management system(RDBMS) is used to build the project integrated database, and the graphical user interface tool(OSF/Motif) on X-window system is used for the integration of application programs and the user interface.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1407-1409
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• 1999

Distance relay is being used for transmission line protection. Recently, current differential relay is used with high reliability in power system. This kind of relay is reported that it has a reliable detection ability, even so high impedance faults take place in transmission line. Therefore it is expected to use and expand widely in many utilities. Tripping of the relay is decided according to the difference between differential and restraint current. However the tripping criterion can be changed by the manufacturers. This paper presents an operational scheme of current differential relay for transmission line protection with graphical model. It is developed for educational purpose for students interesting in power system and protection engineer in utility. MATLAB is used to establish the models.

• International Journal of Reliability and Applications
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• v.11 no.2
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• pp.123-138
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• 2010

This paper investigates a mathematical model of a system composed of two non-identical unit parallel system with common-cause failure, critical human error, non-critical human error, preventive maintenance and two type of repair, i.e. cheaper and costlier. This system goes for preventive maintenance at random epochs. We assume that the failure, repair and maintenance times are independent random variables. The failure rates, repair rates and preventive maintenance rate are constant for each unit. The system is analyzed by using the graphical evaluation and review technique (GERT) to obtain various related measures and we study the effect of the preventive maintenance preventive maintenance on the system performance. Certain important results have been derived as special cases. The plots for the mean time to system failure and the steady-state availability A(${\infty}$) of the system are drawn for different parametric values.

• Communications for Statistical Applications and Methods
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• v.15 no.1
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• pp.27-41
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• 2008

A graphical method of checking the adequacy of a generalized linear model is proposed. The graph helps to assess the assumption that the link function of mean can be expressed as a linear combination of explanatory variables in the generalized linear model. For the graph the boosting technique is applied to estimate nonparametrically the relationship between the link function of the mean and the explanatory variables, though any other nonparametric regression methods can be applied. Through simulation studies with normal and binary data, the effectiveness of the graph is demonstrated. And we list some limitations and technical details of the graph.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.1
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• pp.169-175
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• 2009

Real-time multibody vehicle dynamics software has been developed for virtual handling tests. The software can be utilized for HILS(Hardware In the Loop Simulations) and consists of three modules such as a graphical vehicle modeling preprocessor, a real time dynamics solver, and a virtual reality graphic postprocessor for virtual handling tests. In the graphical vehicle modeling preprocessor, vehicle hard point data for a suspension model are automatically converted into multibody vehicle model. In the real time dynamics solver, the efficient subsystem synthesis method is used to create multibody equations of motion for a subsystem by a subsystem. In the virtual reality graphic postprocessor, an animator has been also developed by using Matlab Virtual Reality Toolbox for virtual handling tests.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.163-168
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• 2009

Given the specific mean shift outlier model, the standard approaches to obtaining test statistics for outliers are discussed. Accuracy of outlier tests is investigated using subset curvatures. These subset curvatures appear to be reliable indicators of the adequacy of the linearization based test. Also, we consider obtaining graphical summaries of uncertainty in estimating parameters through confidence curves. The results are applied to the problem of assessing the accuracy of outlier tests.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.6
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• pp.1973-1993
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• 2022

Model-driven engineering (MDE) and aspect-oriented software development (AOSD) contribute to the common goal of development of high-quality code in reduced time. To complement each approach with the benefits of the other, various methods of integration of the two approaches were proposed in the past. Aspect-oriented code generation, which targets obtaining aspect-oriented code directly from aspect models, offers some unique advantages over the other integration approaches. However, the existing aspect-oriented code generation approaches do not comprehensively address all aspects of a model-driven code generation system, such as a textual representation of graphical models, conceptual mapping, and incorporation of behavioral diagrams. These problems limit the worth of generated code, especially in practical use. Here, we propose AJFCode, an approach for aspect-oriented model-driven code generation, which comprehensively addresses the various aspects including the graphical models and their text-based representation, mapping between visual model elements and code, and the behavioral code generation. Experiments are conducted to compare the maintainability and reusability characteristics of the aspect-oriented code generated using the AJFCode with the most comprehensive object-oriented code generation approach. AJFCode performs well in terms of all metrics related to maintainability and reusability of code. However, the most significant improvement is noticed in the separation of concerns, coupling, and cohesion. For instance, AJFCode yields significant improvement in concern diffusion over operations (19 vs 51), coupling between components (0 vs 6), and lack of cohesion in operations (5 vs 9) for one of the experimented concerns.