• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.75-85
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• 2011

In this paper, using the energy estimates and the bootstrap arguments, the global existence of classical solutions for a prey-predator model with non-monotonic functional response and cross-diffusion where the prey and predator both have linear density restriction is proved when the space dimension n < 10.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.390-395
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• 2010

This study was conducted to predict reduction of soybean yield as affected by different densities of Cuscuta pentagona. All data were fitted to Cousens' rectangular hyperbola model to estimate parameters for predicting soybean yield loss. The yield of soybean in the various densities (1 to 48 plants $m^{-2}$) of C. pentagona reduced by 80.3 to 99.7%, respectively. Among yield components, number of pods was the most significantly influenced by weed interferences. The prediction model for soybean yield as affected by weed competition was as follows: Y= 274.6783/(1+4.3522X), $r^2$=0.999 in C. pentagona. Economic threshold levels calculated using cousens' equation was 0.004 plants $m^{-2}$ in C. pentagona.

• Journal of KIISE:Software and Applications
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• v.33 no.7
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• pp.615-623
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• 2006

A non-functional requirement is a property or quality that the proposed systems have to support the functional requirements. A non-functional requirement is reflected by quality attribute These non-functional requirements playa crucial role during system development, serving as selection criteria for choosing among decisions. It should be continuously considered through the software development process. In spite of the importance of the non-functional requirements, it received little attention because of ambiguousness and invisibility of non-functional requirements. Therefore non-functional model which is a process to analyze the non-functional requirement is proposed for improving the management efficiency of non-functional requirements. Also, this paper presents the trace among the UML diagrams to the conceptual model. According to the non-functional requirement development process, this paper achieved performance-based case study. After then, non-functional requirement should be traced using the UML diagrams.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.4
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• pp.749-756
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• 2013

In this paper, we consider a diffusive delayed predator-prey model with Beddington-DeAngelis type functional response under homogeneous Neumann boundary conditions, where the discrete time delay covers the period from the birth of immature preys to their maturity. We investigate the global existence of nonnegative solutions and the long-term behavior of the time-dependent solution of the model.

• 전기의세계
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• v.24 no.6
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• pp.97-101
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• 1975

The electrical neuronal model described in this paper simulates the most important functional properties of nerve cells. An model circuit incorporating many of the digital and analog properties of neurons is described. Having such properties as variable threshold level, action potential, summation, all-or-none output, absolute and relative refract oriness, and ingibition, it exhibits a considerable amount of functional equivalence to biological structures. This electrical neuronal model has utility not only for studying single unit properties but also for investigating group interactions. Such studies may be relevent to elucidation of neuronal network behavior.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.334-339
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• 1992

This study is concerned how to construct a model of life as physical/ mathematical representation. This model is called here a bionic model and vibrating potential field is introduced as fundamental world background of the model. Namely, required information creating/ processing/ controlling are done on this field. Especially this paper reports how to realize the simulation of a bionic self organization and its functional expression based on the mutual actions among a set of life units.

• Language and Information
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• v.8 no.1
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• pp.101-116
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• 2004

This paper proposes a statistical model for the translation of prepositions in English-Korean machine translation. In the proposed model, statistical information acquired from unlabeled Korean corpora is used to choose the best translation from several possible translations. Such information includes functional word-verb co-occurrence information, functional word-verb distance information, and noun-postposition co-occurrence information. The model was evaluated with 443 sentences, each of which has a prepositional phrase, and we attained 71.3% accuracy.

• Nuclear Engineering and Technology
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• v.46 no.6
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• pp.753-772
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• 2014

The paper presents functional modelling and its application for diagnosis in nuclear power plants. Functional modelling is defined and its relevance for coping with the complexity of diagnosis in large scale systems like nuclear plants is explained. The diagnosis task is analyzed and it is demonstrated that the levels of abstraction in models for diagnosis must reflect plant knowledge about goals and functions which is represented in functional modelling. Multilevel flow modelling (MFM), which is a method for functional modelling, is introduced briefly and illustrated with a cooling system example. The use of MFM for reasoning about causes and consequences is explained in detail and demonstrated using the reasoning tool, the MFMSuite. MFM applications in nuclear power systems are described by two examples: a PWR; and an FBR reactor. The PWR example show how MFM can be used to model and reason about operating modes. The FBR example illustrates how the modelling development effort can be managed by proper strategies including decomposition and reuse.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1051-1054
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• 2008

The entropy production in a non-equilibrium state based on the reversible Oregonator model of the Belousov-Zhabotinskii (BZ) reaction system has been studied. The reaction affinity and the reaction rate for the individual steps have been calculated by varying the concentrations of key variables in the system. The result shows a linear relationship between the reaction affinity and the reaction rate in the given concentration range. However, the overall entropy calculated on the basic assumption that the entropy in a reaction system corresponds to the summation of a product of reaction affinity and reaction rate of individual steps shows a nonlinearity of the reaction system. The results well agrees with the fact that the entropy production is not linear or complicated function in a non-linear reaction system.

• Proceedings of the Korean Society for Information Management Conference
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• 2002.08a
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• pp.103-108
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• 2002

IFLA는 개체-관계모형을 기반으로 하여 서지레코드가 수행해야 할 기능에 관한 '서지레코드의 기능상 요건에 관한 모형'(Functional Requirements for Bibliographic Records: FRBR Model)을 발표하였다. 본 연구에서는 FRBR 모형의 비평적 분석을 통하여 새로운 목록규칙에 대한 방안을 모색하고자 한다.