• Journal of applied mathematics & informatics
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• v.6 no.3
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• pp.697-726
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• 1999

In this paper we develop a now procedure to control stepsize for linear multistep methods applied to semi-explicit index 1 differential-algebraic equations. in contrast to the standard approach the error control mechanism presented here is based on monitoring and contolling both the local and global errors of multistep formulas. As a result such methods with the local-global stepsize control solve differential-algebraic equation with any prescribed accuracy (up to round-off errors). For implicit multistep methods we give the minimum number of both full and modified Newton iterations allowing the iterative approxima-tions to be correctly used in the procedure of the local-global stepsize control. We also discuss validity of simple iterations for high accuracy solving differential-algebraic equations. Numerical tests support the the-oretical results of the paper.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.1
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• pp.48-54
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• 2017

A minimum turning circle test of vehicles is operated by using Real-Time Kinematic(RTK) surveying method which enhances the precision of the Global Positioning System(GPS). A procedure of the conventional method to obtain results is to take post processing after the test. Therefore, it is difficult to ensure results in an instant. This paper introduces developed process and equipment that can immediately obtain results after the minimum turning test without post processing.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.17-24
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• 1995

This work proposes an optimality criteria applicable to the optimum design of plane frames. Stress constraints as well as displacement constraints are treated as behavioural constraints and thus the first order approximation of stress constraints is adopted. The design space of practical reinforced concrete frames with discrete design variables has been found to have many local minima, and thus it is desirable to find in advance the mathematical minimum, hopefully global, prior to starting to search a practical optimum design. By using the mathematical minimum as a trial design of any search algorithm, we may not full into a local minimum but apparently costly design. Therefore this work aims at establishing a mathematically rigorous method ⑴ by adopting first-order approximation of constraints, ⑵ by reducing the design space whenever minimum size restrictions become "active" and ⑶ by the of Newton-Raphson Method.

• Journal of Korea Multimedia Society
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• v.3 no.4
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• pp.356-364
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• 2000

Block based fast motion estimation algorithm use the fixed search pattern to reduce the search point, and are based on the assumption that the error in the mean absolute error space monotonically decreases to the global minimum. Therefore, in case of many local minima in a search region we are likely to find local minima instead of the global minimum and highly rely on the initial search points. This situation is evident in the motion boundary. In this paper we define the candidate regions within the search region using the motion information of the neighbor blocks and we propose the multiple local search method (MLSM) which search for the solution throughout the candidate regions to reduce the possibilities of isolation to the local minima. In the MLSM we mark the candidate region in the search point map and we avoid to search the candidate regions already visited to reduce the calculation. In the simulation results the proposed method shows more excellent results than that of other gradient based method especially in the search of motion boundary. Especially, in PSNR the proposed method obtains similar estimate accuracy with the significant reduction of search points to that of full search.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.129-134
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• 2008

In this paper, we carry out the simulation for an optimal solution of one-dimensional nonlinear photonic crystal structure using Genetic algorithm, and show the proposed method to apply for photonic transistors. Unlike a conventional steepest descent method for an optimization, the proposed method based on Genetic Algorithm has advantages for finding out excellent solutions without any analytic forms, which can easily apply to other applications. Also, as several solutions around global minimum solution can be obtained, it is very good optimization tool to give us the patterns about the optimal structure of a photonic crystal transistor. To design an all-optical filter transistor, Neural network algorithm is firstly performed for an initial design and then Genetic Algorithm is finally used to get the optimal solution. From the simulation of one-dimensional photonic crystal transistor, 27dB of the switching On/Off ratio is obtained.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.351-360
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• 2005

This paper finds a new class of generalized convex function which satisfies the following properties: It's level set is $\eta$-convex set; Every feasible Kuhn-Tucker point is a global minimum; If Slater's constraint qualification holds, then every minimum point is Kuhn-Tucker point; Weak duality and strong duality hold between primal problem and it's Mond-Weir dual problem.

• Journal of the Korean Professional Engineers Association
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• v.42 no.1
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• pp.34-38
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• 2009

There are three major international agreements governing mutual recognition of engineering qualifications and professional competence of the International PEs; namely, Washington Accords, APEC engineer agreement and EMF agreement. International Organizations of APEC Engineer Coordinating Committer and Engineers Mobility Forum established international registries with the goal of improving international mobility. APEC and EMF membership requires minimum qualifications for licensure with the minimum standards including engineering education, Professional experience, compliance with home jurisdiction requirements, having verified record of responsible charge, and demonstrating a commitment to continuing education.

• Journal of the Korea Society of Computer and Information
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• v.18 no.1
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• pp.137-147
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• 2013

The RFID(Radio Frequency Identification) and the WSN(Wireless Sensor Network) have technical similarities and mutual effects, they have been recognized to be studied separately, and sufficient studies have not been conducted on the technical integration of the RFID and the WSN. Therefore, EPC global which realized the issue proposed the EPC(Electronic Produce Code) Sensor Network to efficiently integrate and interoperate the RFID and WSN technologies based on the international standard EPC global network. The proposed EPC Sensor Network technology uses the Complex Event Processing method in the middleware to integrate data occurring through the RFID and the WSN in a single environment and to interoperate the events based on the EPC global network. However, as the EPC Sensor Network technology continuously performs its operation even in the case that the minimum conditions are not to be met to find complex events in the middleware, its operation cost rises. Therefore, to address the problems of the existing system, we defined the minimum conditions of the complex events to detect unnecessary complex events in the middleware, and proposed an algorithm that can extract complex events only when the minimum conditions are to be met. To examine the minimum conditions, a index and a query index are used to extract complex events. To evaluate the performance of the proposed methods, In the case of the method of extracting complex events based on a bitmap index, we used the existing extraction method and NS2 simulation to evaluate its performance and thus to show its good performance in terms of the number of operation and the processing time for the complex events.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.204-213
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• 1999

This paper suggests a numerical method of finding optimal geometric path and minimum-time motion for a manipulator arm. To find the minimum-time motion, the optimal geometric path is searched first, and the minimum-time motion is searched on this optimal path. In the algorithm finding optimal geometric path, the objective function is minimizing the combination of joint velocities, joint-jerks, and actuator forces as well as avoiding several static obstacles, where global search is performed by adjusting the seed points of the obstacle models. In the minimum-time algorithm, the traveling time is expressed by the linear combinations of finite-term quintic B-splines and the coefficients of the splines are obtained by nonlinear programming to minimize the total traveling time subject to the constraints of the velocity-dependent actuator forces. These two search algorithms are basically similar and their convergences are quite stable.

• Journal of Korea Port Economic Association
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• v.35 no.2
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• pp.37-60
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• 2019

An analysis of the correlation in port-related industries between minimum wage and employment effects, showed that it was very insignificant. However, there are some differences between commercial and temporary workers, those that are self-employed, and other workers in the private sector. Thus, while commercial workers are somewhat stable, they have a somewhat negative effect on temporary workers and self-employed people. At the Minimum Wage Council, the minimum wage hike is seen as stable because of the interaction between income and substitution effects in the labor market. According to the analysis, the port-related industries were affected more by the global economic recession and domestic economic volatility than the variables related to the minimum wage hike.