• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.187-193
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• 2008

Cross docking is a warehouse management concept in which items delivered to a distribution facility by inbound trucks are immediately sorted out and reorganized based on customer demands and are routed and loaded into outbound trucks for delivery to customers without actually being held in inventory in the distribution facility. In this research, the design of distribution facility for cross docking systems was studied. The objective of this research is to find the minimum number of receiving docks and shipping docks, respectively, in order to meet the daily demand of the distribution center. Two solution approaches are employed in modeling and solving the problem The first approach is mathematical modeling and the second approach is a simulation. The logic developed in the simulation model is expected to apply to the real world situation.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.73-87
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• 1998

Recently experimental class model is growingly recommended for mathematics instruction. Freudenthal(1973) points out the difficulties of learning probability and Fischebien suggested to teach probability more intuitively through games. However detailed explanations for such classes are not easy to find. This paper is to give more detailed materials for those lessons and to check its effectiveness. We give 6 topics of probability and statistics being taught in our middle school, such as histogram, concept of probability, probability calculations, expectations, standard deviations, and correlations and each of which is given along with the experimental materials to be used. We perform a trial of the methods and found some encouragement in the students' mathematical attitudes and interests but not in the achievements. We belive that the drawback of the achievement result is due to the short length of time of our experiments.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.299-312
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• 1998

In this study, we have investigated the meaning and mechanism of the 'construction' in the operational constructivism and the social constructivism. According to Piaget, a mathematical concept is the operational sch me, which is constructed through the reflective abstraction from a general coordination of activities and operations. The process of the reflective abstraction consists of 'reflechissement'and 'reflexion'. The reflechissement starting from 'intriorisation' concludes with 'thematisation', and the reflexion consists in the 'equilibration' of the result of reflechissement. The 'construction' in the social constructivism includes two process. One is the process from the individual, subjective knowledge of mathematics to the social, objective knowledge of mathematics, and the other is vice versa. The emphases is placed on the 'social interaction' and the 'representation' in this two processes. In this context, if we want to apply the social constructivism, we should clarify the meaning of 'society', and consider the difference between the society of mathematicians and the society of students.

• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.205-211
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• 2010

In this study, a Magnetic stimulation Pulse Train control technique is introduced and applied to Flyback converter operating in discontinuous conduction mode. In contrast to the conventional pulse width modulation control scheme, the principal idea of a Magnetic stimulation Pulse Train is to achieve output voltage regulation using high and low power pulses. The proposed technique is applicable to any converter operating in discontinuous conduction. However, this work mainly focuses on Flyback topology. In this paper, the main mathematical concept of the new control algorithm is introduced and simulations as well as experimental results are presented.

• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.64-74
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• 2015

Because of the burgeoning demand of the energy, the countries are finding sustainable solutions for these emerging challenges. Demand Side Management is playing a significant role in managing the demand with an aim to support the electrical grid during the peak hours. However, advancement in controls and communication technologies, the aggregators are appearing as a third party entity in implementing demand response program. In this paper, a detailed mathematical framework is discussed in which the aggregator acts as an energy service provider between the utility and the consumers, and facilitate the consumers to actively participate in demand side management by introducing the new concept of demand reduction bidding (DRB) under constrained direct load control. Paper also presented an algorithm for the proposed framework and demonstrated the efficacy of the algorithm by considering few case studies and concluded with simulation results and discussions.

• The Pure and Applied Mathematics
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• v.21 no.1
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• pp.23-38
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• 2014

In this paper, we introduce the concept of w¡compatibility and weakly commutativity for hybrid pair of mappings $F:X{\times}X{\times}X{\rightarrow}2^X$ and $g:X{\rightarrow}X$ and establish a common tripled fixed point theorem under generalized nonlinear contraction. An example is also given to validate our result. We improve, extend and generalize various known results.

• The Pure and Applied Mathematics
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• v.27 no.4
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• pp.187-205
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• 2020

In this article, we prove coincidence point theorems for comparable 𝜓-contractive mappings in ordered non-Archimedean fuzzy metric spaces utilizing the recently established concept of 𝓣-comparability and relatively weaker order theoretic variants. With a view to show the usefulness and applicability of this work, we solve the system of ordered Fredholm integral equations as an application. In the process, this presentation generalize and improve some prominent recent results obtained in Mihet [Fuzzy Sets Syst., 159 (6), 739-744, (2008)], Altun and Mihet [ Fixed Point Theory Appl. 2010, 782680, (2010)], Alam and Imdad [Fixed Point Theory, 18(2), 415-432, (2017)] and several others in the settings of partially ordered non-Archimedean fuzzy metric spaces.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.121-128
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• 2005

This study presents an effective stiffness-based optimal technique to control quantitatively lateral drift for shear wall structures subject to lateral loads. To this end the displacement sensitivity depending on behavior characteristics of shear wall structures is established. Also, the approximation concept that can preserve the generality of the mathematical programming and can efficiently solve large scale problems is introduced. Resizing sections in the stiffness-based optimal design are assumed to be uniformly varying in size and the technique of member grouping is considered for the improvement of construction efficiency Two types of 11-story shear wall structures are presented to illustrate the features of the quantitative lateral drift control technique proposed in this study.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.343-350
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• 2005

A constitutive model was implemented in ABAQUS code. The constitutive equation can model the behavior for overall range of strain level from small to large deformation, which is based on anisotropic hardening rule and total stress concept. The formulation includes (1) finite strain formulation on the basis of Jaumann rate, (2) implicit stress integration and (3) consistent tangent moduli. Therefore the mathematical background was established in order that large deformation analysis can be performed accurately and efficiently with the anisotropic constitutive model. In the large deformation analyses, geometric nonlinearity was considered and the result of analyses with the proposed model was compared with that of Mises model for the overall strain range behavior.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.125-132
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• 2001

Heat dissipation technology using flow resonant phenomenon is a kind of new concept in heat transfer area. A vibration exciter is needed to generate air turbulence which has the natural shedding frequency of heat system. A mechanical vibrating device for the air flow oscillation is introduced, which is driven by a moving coil actuator. An analytical dynamic model for this mechanical vibration exciter is presented and its' validity is verified by the comparison with experimental data. Values of some unknown system parameters in the analytic model are estimated through the system identification approach. Based on this mathematical model, the vibration exciter using strain displacement estimator is developed. And in the experiment, the feedback control is used. During the experimental verification phase, it turns out the high modal resonant characteristics of vibrating plate are the major barrier against obtaining a high bandwidth vibration exciter.