• Journal of the Korea Society for Simulation
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• v.21 no.4
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• pp.35-46
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• 2012

As complexity of real-time systems is being increased ad hoc approaches to analysis of such systems would have limitations in completeness and coverability for states space search. Formal means using a model-based approach would solve such limitations. This paper proposes a model-based formal method for logical analysis, such as safety and liveness, of real-time systems at a discrete event system level. A discrete event model for real-time systems to be analyzed is specified by DEVS(Discrete Event Systems Specification) formalism, which specifies a discrete event system in hierarchical, modular manner. Analysis of such DEVS models is performed by Communicating DEVS (C-DEVS) formalism of a timed global state transition specification and an associated analysis algorithm. The C-DEVS formalism and an associated analysis algorithm guarantees that all possible states for a given system are visited in an analysis phase. A case study of a safety analysis for a rail road crossing system illustrates the effectiveness of the proposed method of the model-based approach.

• Journal of Korean Institute of Industrial Engineers
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• v.9 no.1
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• pp.7-15
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• 1983

This paper analyses and represents the various static and dynamical aspects of the production management problems by graphical methods. For this, eight graphical formal models are investigated and compared in terms of their ability to express twelve typical features for the structure of production planning.

• The Journal of the Acoustical Society of Korea
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• v.15 no.2E
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• pp.8-13
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• 1996

The pseudomedian filter was designed to be a computationally effecient alternative to the median filter. However, a thorough analysis ofter pseudomedian filter reveals some important differences between its response and that of the median filter. This paper develops some formal properties of the pseudomedian filter. The root signal analysis demonstrates the close relatonship between the median and pseudomedian filters while pointing out important and useful differences.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.640-655
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• 2013

The purpose of this study is to analyze the cognitive demands level of the description about 'changes of state' and 'kinetic theory' on the 'science 1' textbooks by the 2007 revised curriculum. The three types of curriculum analysis taxonomy have been used to analyze the cognitive demands level of those contents on the 6 kinds of 'science 1' textbooks. The most higher level of cognitive demands about the concepts have been discussed here due to the focus of the concepts. The first, the cognitive demand level about 'three states of substances' depending on the motion of their particles in 6 textbooks is a early formal operational stage because of using by the application of kinetic theory. The second, the cognitive demand level about 'diffusion' and 'evaporation' is a early formal operational stage, because the particles move around faster so they can change their position. The third, the cognitive level of the pressure and volume in a gas is a early formal operational stage because of explaining only phenomena in simple correspondence with formal model of kinetic theory. And simple functional relationships beyond linear on the graph of the volume and pressure of gas, the volume and temperature of gas is also a early formal operational stage. The fourth, the cognitive level of the energy of heat by a change of the state is also a early formal operational stage because kinetic theory picture accepted as providing explanation by the change of the state. And functional relationships beyond linear on the graph of the explanation of boiling point of water in water is also a early formal operational stage.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.229-235
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• 2018

The purpose of this study is to propose a method to utilize Big Data Analysis to find policy issues of local governments in the reality that utilization of big data becomes increasingly important in efficient and effective policy making process. For this purpose, this study analyzed the 180,000 articles of Suwon city for the past three years and identified policy issues and evaluated policy priorities through IPA analysis. The results of this study showed that the analysis of semi-formal big data through newspaper articles is effective in deriving the differentiated policy issues of different local autonomous bodies from the main issues in the nation, In this way, the methodology of finding policy issues through the analysis of big data suggested in this study means that local governments can effectively identify policy issues and effectively identify the people. In addition, the methodology proposed in this study is expected to be applicable to the policy issues through the analysis of various semi - formal and informal big data such as online civil complaint data of the local government, resident SNS.

• Journal of The Korean Association For Science Education
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• v.19 no.2
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• pp.275-292
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• 1999

This study aimed to explore the saliences of formal school science and their influences on the attitude toward science communication through mass media. Saliences of school science are salient memories of school science which a perciever attends to selectively among various aspects of formal school science. Among saliences. external saliences refer to the sensory aspects of formal school science. and internal saliences refer to the observers' cognition. Attitude toward science communication through mass media constitute six scales; exposure. cognition. focus. belief. self perception of understanding. application. The questionnaire were developed and sample was selected by multi-stage stratified clustering. The sample size was 1,825. The data was analysed by correlation and multiple stepwise regression. Positive saliences were lab work and science teacher and negative saliences were lecture and exam/grade. According to the correlation and multiple stepwise regression analysis. saliences of the formal school science could account only a small part of the attitude toward science communication through mass media. Internal salieces could account the attitude toward science communication than external salience. Further studies on new models including attitude towards science are needed.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.11
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• pp.952-957
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• 2003

We propose how to translate relay circuits to the EMFGs(Extended Mark Flow Graphs) formally and analyze the original one by using the mark flow of it. Firstly, the concepts of the output condition, the output-on condition and the output-off condition are introduced in the relay circuits. These can be used to find the structure and the operation of respective relay outputs but the sequential operations of them cannot be obtained from these. Secondly, a relay circuit is translated to the corresponding EMFG as the all output-on conditions and all output-off conditions of it are translated to EMFGs. For the adequate translation, the condition arc and the concepts of the generation transition and the degeneration transition are introduced, and the duality for the simplification of the result. Thirdly, we analyze the operation of the original circuit by analyzing the mark flow of the resulting EMFG. We can achieve easy and fast analysis based on the EMFG's operation algorithm. Finally, we apply these to the relay circuit for an electric furnace and analyze its operation with the mark flow of the resulting EMFG. The formal translation from relay circuits to EMFGs makes the analysis easy so that these results can be used to design, modelling, the fault detection and the maintenance.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.817-827
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• 2001

This study tried to investigate whether characteristics of the perceiver and image of ideal woman made differences in the important factors for the selection clothing and the preference of clothing. A poll of 650 men & women between the ages of 20-39 living in Daegu was taken for this study. Factor analysis, cluster analysis, frequency, ANOVA-test, t-test, and $\chi$$^2$-test were implemented with the SPSS-package. The characteristics of clothing types used in this study included: sexy, masculine, feminine, dramatic, elegant-classic, and casual. The results were as follows. 1. In the situation of first impression formation, the characteristics of the perceiver made differences in the selection of clothing types. Women took self-satisfaction and fashion factors to be more important than men, so did persons in their 20s than 30s. And the unmarried took self-satisfaction factor to be more important than the married. 2. Men and women had different images of the ideal woman. Under special situations of first impression formation, such as, formal blind dates on the condition of marriage and casual blind dates, there were differences in clothing preference.

• Nuclear Engineering and Technology
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• v.31 no.2
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• pp.157-171
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• 1999

In this work, an automatic software verification method for Nuclear Power Plant (NPP) protection system is developed. This method utilizes Colored Petri Net (CPN) for system modeling and Prototype Verification System (PVS) for mathematical verification. In order to help flow-through from modeling by CPN to mathematical proof by PVS, an information extractor from CPN models has been developed in this work. In order to convert the extracted information to the PVS specification language, a translator also has been developed. ML that is a higher-order functional language programs the information extractor and translator. This combined method has been applied to a protection system function of Wolsong NPP SDS2(Steam Generator Low Level Trip). As a result of this application, we could prove completeness and consistency of the requirement logically. Through this work, in short, an axiom or lemma based-analysis method for CPN models is newly suggested in order to complement CPN analysis methods and a guideline for the use of formal methods is proposed in order to apply them to NPP Software Verification and Validation.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.2
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• pp.442-454
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• 1997

The purpose of this study was 1) to identify the effects of lifestyle activities and decision -making related variables (shopping orientations, use of information sources and importance of store attributes) on the outshopping behavior of female consumers in Seoul and satellite cities, and 2) to investigate the differences in the effects of those variables on the outshopping behavior among 4 clothing categories (formal wear, separates, casual wear, underwear). The data were collected via a questionnaires from 508 adult females of ages over 20's living in Seoul and satellite cities around Seoul and were analyzed by factor analysis and discriminant analysis. The results of this study were as follows: 1) Some of the factors of 4 decision-making related variables significantly discriminated the outshoppers and inshoppers. The most influential factors were attitude toward imported products, time-oriented and price-oriented attitude of shopping orientations. 2) There were significant differences in the effects of 4 variables on outshopping behaviors among 4 clothing categories. More factors were effective in discriminating the outshopping behavior for formal wear or separates purchase.