• Journal of the Korean Mathematical Society
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• v.50 no.3
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• pp.627-639
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• 2013

The goal of this paper is to obtain the regularity and the existence of solutions of a retarded semilinear differential equation with nonlocal condition by applying Schauder's fixed point theorem. We construct the fundamental solution, establish the H$\ddot{o}$lder continuity results concerning the fundamental solution of its corresponding retarded linear equation, and prove the uniqueness of solutions of the given equation.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.307-314
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• 2005

In this paper we consider positive solutions of the following difference equation $$x_{n+l}\;=\;min[{\frac{A}{x_{n}},{\frac{B}{x_{n-2}}}],\;A,B\;>\;0$$. We prove that every positive solution is eventually periodic. Also, we present here some results concerning positive solutions of the difference equation $$x_{n+l}\;=\;min[{\frac{A}{x_{n}x_{n-1}{\cdots}x_{n-k}},{\frac{B}{x_{n-(k+2)}{\cdots}x_{n-(2k+2)}}],\;A,B\;>\;0$$.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.1-10
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• 1989

This paper deals with a single-facility multiproduction model concerning the basic cyclic scheduling. The aim is to obtain the production order of each product in a cycle and the cycle frequency for minimizing the setup costs and inventory carrying costs of all products. The problem is formulated by LP and it shows that the optimal solution derived dominates the solution of non-cyclic scheduling model on some conditions.

• Journal of applied mathematics & informatics
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• v.7 no.1
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• pp.41-60
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• 2000

In this paper we consider a series of algorithms for calculating radicals of matrix polynomial equations. A particular aspect of this problem arise in author's work. concerning parameter identification of linear dynamic stochastic system. Special attention is given of searching the solution of an equation in a neighbourhood of some initial approximation. The offered approaches and algorithms allow us to receive fast and quite exact solution. We give some recommendations for application of given algorithms.

• Journal of the Korean institute of surface engineering
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• v.10 no.1
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• pp.1-18
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• 1977

To support the domestic plating industry concerning localized products, survey was conducted in with chemicals and properties of plating solution. Collected samples from 55 factories throughout the country were investigated by spectigated by spectrograph, Hull cell test chemical analysis method to find major chemical components of the plating solution.

• Journal of Family Relations
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• v.23 no.1
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• pp.139-156
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• 2018

Objectives: The purpose of this study is to examine the impact of solution- focused thinking on middle-aged married women's role adjustment and life satisfaction through positive emotions. Method: The subjects of this study is middle-aged married women who reside in an urban community in South Gyeongsang Province. As for data analysis, SPSS 22.0 and AMOS 21.0 are employed. Results: The findings of the study were as follows: First, concerning the relationships of the variables, there were significant positive correlations among all the solution-focused thinking, positive emotions, role adjustment and life satisfaction. Second, solution-focused thinking had significant direct effect on positive emotions, and role adjustment. Solution-focused thinking had significant indirect effect on role adjustment through the medium of positive emotions at the same time. Solution-focused thinking had a significant indirect effect on life satisfaction through the medium of positive emotions and role adjustment. Positive emotions had no direct effect on life satisfaction but had a significant indirect effect on it through the medium of role adjustment. Conclusions: The findings of the study conclude that solution-focused thinking exercised an indirect influence on life satisfaction through the medium of positive emotions and role adjustment made it possible to find a way to provide solution-focused counseling for clients to lead a more satisfactory life.

• Journal of Plant Biology
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• v.8 no.1_2
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• pp.1-4
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• 1965

Beta-ray irradiation effects on structural changes of the chromosomes in root tip of rye, Secale cereale L., seedlings, particularly the frequency of chromosome bridge induction at anaphase stage treated with radioactive sulfur (S35) solutions were studied in this experiment. Among the four different concentrations of isotope solution, the lowest one, 0.4$\mu$c solution, has shown weak effect on the induction of chromosome aberration. On the other hand, higher concentration, 25.6$\mu$c solution, induced higher frequency of chromosome bridge induction as much as 4.3%. Concerning the relationship between the ages of after treatment and the ranges of concentration, the higher concentrations showed more pronounced effects than the lower ones.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.11 no.1
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• pp.52-57
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• 2005

Objectives : Recurrent pregnancy loss occurs in approximately 0.5-3% of women. There are many studies concerning immunological factor recently. Therefore, aim of this study is to examine the latest trend of researches concerning recurrent pregnancy loss, and controlled experiment on animals about antiphospholipid antibody. Method : We referred Pubmed site by using searching word of 'recurrent pregnancy loss' (Limits : 2000.1-2004.3, animal) Results and conclusions : 1. We searched 29 papers. Immunological factor : 18 ( about antiphospholipid antibody : 10 ), Chromosomal abnormality : 6, The others : 5 2. In five papers about controlled experiment on animals, (1) Materials : 8-12 weeks old mice / 11.5-day old-rat embryos / New Zealand rabbit (2) Inductions : inject intraperitoneally with human IgG containing antiphospholipid antibodies / culture in a solution of 1 ml medium which contained IgG purified from sera of women / inject intradermally with cardiolipin (3) Treatments : inject intraperitoneally with complement component before / culture in a solution of 1 ml medium which contained IgG purified from sera of women with SLE and RPL or from healthy women / inject intradermally with TFX, 0.9% NaCl (4) Measurements : weight fetuses and placentas, calculate frequency of fetal resorption / after culture, examine the embryos / examine platelet counts, APTT and numbers of live and dead newborns, resorbed fetuses, body mass, newborn viability and survival rates.

• Journal of Information Processing Systems
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• v.15 no.5
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• pp.1243-1257
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• 2019

As current algorithms unable to perform effective fusion processing of unknown complex radar signals lacking database, and the result is unstable, this paper presents a multi-level fusion processing algorithm for complex radar signals based on evidence theory as a solution to this problem. Specifically, the real-time database is initially established, accompanied by similarity model based on parameter type, and then similarity matrix is calculated. D-S evidence theory is subsequently applied to exercise fusion processing on the similarity of parameters concerning each signal and the trust value concerning target framework of each signal in order. The signals are ultimately combined and perfected. The results of simulation experiment reveal that the proposed algorithm can exert favorable effect on the fusion of unknown complex radar signals, with higher efficiency and less time, maintaining stable processing even of considerable samples.

• Corrosion Science and Technology
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• v.2 no.1
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• pp.41-46
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• 2003

Flow-Accelerated Corrosion behavior concerning both activation and mass transfer process of SA106 Gr.C steel was studied using rotating cylinder electrode in room temperature alkaline solution by DC and AC electrochemical techniques. Passive film was tanned from pH 9.8 by step oxidation of ferrous product into hydroxyl compound. Corrosion potential shifted slightly upward with rotating velocity through the diffusion of cathodic species. Corrosion current density increased with rotating velocity in pH 6.98, while it soon saturated from 1000 rpm at above pH 9.8. On the other hand the limiting current increased with rotating speed regardless of pH values. It seems that activation process, which represents formation of passive film on the bare metal surface, controls the entire corrosion kinetics