• Journal of the Korean earth science society
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• v.21 no.4
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• pp.369-379
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• 2000

The purposes of this study is to identify the misconceptions on atmospheric pressure and to investigate the effect of conceptual change of the cognitive conflict teaching models. The subjects are 184 students in girls' high school and divided into the controlled and test group. Before instruction on atmospheric pressure concept, their concept types were identified and their conceptual changes were compared after instruction by the traditional and the cognitive conflict teaching models. The results of this study are as follows; 1 ) The students' understanding level on the atmospheric pressure was low before instruction and they had some misconceptions. But the concept levels related to their everyday life experieces and memorized concept were high. 2) The cognitive conflict teaching model were more effective than the traditional teaching model in the formation of atmospheric pressure concept. 3) Though there were some differences among the test items, the cognitive conflict teaching model was identified to be more effective than the traditional teaching model in terms of the durability of atmospheric pressure concept.

• Journal of the military operations research society of Korea
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• v.8 no.2
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• pp.17-30
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• 1982

This paper offers an optimal artillery deployment scheme for the defending unit when two forces are confronted at a military front line. When proposed gun sites, types and number of guns as well as targets are given, the solutions of the two models in this paper direct each (unit of) guns to a certain location. The aim of the models is to maximize the number of guns which can hit important targets. Unlike widely used target assignment models, these models are formulated using the set covering problem concept. These models do not contain probabilities and time. Thus they are simple as models, easy in implementation, and yield tractable solutions. The dynamic and probabilistic feature of battle situations is implicitly reflected on the models. The first model is for the case that enemies' approaching route is clearly predictable, while the second model is for the unpredictable approaching route case.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.37-40
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• 2003

The thrust vector control using a fluidic counterflow concept is achieved by applying a vacuum to a slot adjacent to a primary jet which is shrouded by a suction collar. The vacuum produces a secondary reverse flowing stream near the primary. The shear layers between the two counterflowing streams mix and entrain mass from the surrounding fluid. The presence of the collar inhibits mass entrainment and the flow m the collar accelerates causing a drop in pressure on the collar. For the vacuum asymmetrically applied to one side of the nozzle, the jet will vector toward the low-pressure region. The present study is performed to investigate the effectiveness of thrust vector control using the fluidic counterflow concept. A computational work is carried out using the two-dimensional, compressible Navier-Stokes equations, with several kinds of turbulence models. The computational results are compared with the previous experimental ones. It is found that the present fluidic counterflow concept is a viable method to vector the thrust of a propulsion system.

• Korean System Dynamics Review
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• v.14 no.2
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• pp.5-30
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• 2013

The concept of resilience in complex and adaptive socio-economic systems, has been a buzz word in international societies and academies related to policy makers for sustainable development since some years ago. This paper deals with an application of the resilient concept, which has been told since the last some decades in the field of ecology and applied system sciences, to social science especially in system dynamics. First the author introduces the concept of equilibrium stability and resilience in simple dynamic models, and moreover provides the behavioral characteristics and examples of system resilience in terms of system dynamics. The concept of resilience in structural perspectives are also discussed with the topics of panarchy and adaptive renewal cycles, etc.

• International Journal of Human Ecology
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• v.13 no.2
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• pp.1-13
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• 2012

This study examined the effects of academic self-concept (internal factor) and maternal parenting behaviors (external factor) on academic delay of gratification (ADOG). Additionally, models predicting ADOG were compared between Korean and Malaysian children. The participants of this study were 100 Korean third graders and their mothers, and 100 Malaysian third graders and their mothers. The children completed the modified versions of the Academic Delay of Gratification Scale for Children, and Academic Self-Concept Questionnaire. The mothers completed the Parenting Attitude Test. Pearson's correlation tests, independent t-tests, and multiple regression analyses were conducted to test the research hypotheses. The results showed that Korean children reported higher ADOG and academic self-concept scores than that of Malaysian children. Moreover, academic self-concept was found to have a significant positive effect on ADOG among both Korean and Malaysian children. There was no significant gender difference in ADOG for both Korean and Malaysian children. However, the effects of maternal parenting behaviors on ADOG were only detected among the Malaysian children, particularly on Achievement Press. That is, only for the Malaysian children, maternal pressure about academic achievement was found to have a significant positive effect on ADOG. In conclusion, only academic self-concept was found to be a significant predictor explaining the variance in ADOG among Korean children. On the other hand, academic self-concept and maternal parenting behaviors were shown as significant predictors explaining the variance in ADOG among Malaysian children.

• Journal of Service Research and Studies
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• v.4 no.1
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• pp.123-132
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• 2014

In this study, the service concept was explained, which could be applied to the development process of new service in service design specially. The service concept has the important role in decision making in the service planning stage as to the new strategic service development or service remodelling. This service concept is very useful for customized operational planning or service recovery through the combination of various service element, and for reviewing the possibility of service's success as of customer's acceptance related to business model throughout the service concept test. Finally, in this study, some models are suggested that the service development model including the service concept, also the test model about service concept in the process of service development.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.15 no.2
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• pp.87-95
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• 2015

In this study, we pursue a new direction for system modeling by introducing the concept of granular models, which produce results in the form of information granules (such as intervals, fuzzy sets, and rough sets). We present a rationale and several key motivating arguments behind the use of granular models and discuss their underlying design processes. The development of the granular model includes optimal allocation of information granularity through optimizing the criteria of coverage and specificity. The emergence and construction of granular models of type-2 and type-n (in general) is discussed. It is shown that achieving a suitable coverage-specificity tradeoff (compromise) is essential for developing granular models.

• The Journal of Advanced Prosthodontics
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• v.9 no.1
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• pp.31-37
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• 2017

PURPOSE. The purpose of this study was to analyze the influence of the platform switching concept on an implant system and peri-implant bone using three-dimensional finite element analysis. MATERIALS AND METHODS. Two three-dimensional finite element models for wide platform and platform switching were created. In the wide platform model, a wide platform abutment was connected to a wide platform implant. In the platform switching model, the wide platform abutment of the wide platform model was replaced by a regular platform abutment. A contact condition was set between the implant components. A vertical load of 300 N was applied to the crown. The maximum von Mises stress values and displacements of the two models were compared to analyze the biomechanical behavior of the models. RESULTS. In the two models, the stress was mainly concentrated at the bottom of the abutment and the top surface of the implant in both models. However, the von Mises stress values were much higher in the platform switching model in most of the components, except for the bone. The highest von Mises values and stress distribution pattern of the bone were similar in the two models. The components of the platform switching model showed greater displacement than those of the wide platform model. CONCLUSION. Due to the stress concentration generated in the implant and the prosthodontic components of the platform switched implant, the mechanical complications might occur when platform switching concept is used.

• Journal of Families and Better Life
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• v.13 no.4
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• pp.1-14
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• 1995

Various theoretical models have developed io both a family research area and family therapy field on he basis of several family theories and social theories in order to understand the family life and its function. These theoretical models have give rise to provide not only a framework for family therapy bt also opportunities for the development of family studies. Regardless of the devotion of these theoretical models to a family therapy however some family therapy professions have suggested the disvergence between these models and practice because the models tend to confuse therapists in their actual practices Other family therapists on the other hand have claimed the convergence between these models and practice. One of the reasons for the issues of convergence and disvergence in the family therapy study would be that various theoretical models have different sometimes contradicatable definitions and explanations for same concept. Therefore the purpose of this paper is to investigate the extent of similarities and differences among these theoretical models of practice in a way of examining family models to compare Olson's circumplex model to the Beavers systems model. Both models were based on the general systems theory. This paper consists of the explanation of Olson's circumplex model and Beavers systems model in general respectively. Then it will investigate similarities and differences between these two models in terms of the relationship between family functioning and family adaptability.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.175-184
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• 1993

Modeling the production process is a necessary and essential aspect of the production planning. This paper introduces a theoretical model of the multi-stage production process. A multi-stage production process is regarded as a network of interrelated production activities which use system exogenous inputs of goods in production and the intermediate products transfers between activities to produce final products. Our model is characterized by (1) a few of the production-related assumptions and (2) two types of elements "goods and activities" that are represented in terms of the network terminology. This model is different from the another multi-stage production models, so-called production network models in relation to the production-theoretical concept. It is not based on the concept of the production correspondence and the activity production functions, but the technology model of Koopmans. Koopmans.