• Journal of Power Electronics
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• v.14 no.2
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• pp.351-361
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• 2014

The discrete torque generation mechanism and inherently nonlinear magnetic characterization of switched reluctance motors lead to unacceptable torque ripples and limit the application of these motors. In this study, a phase current profiling technique and torque sharing function are proposed in consideration of magnetic saturation effects and by minimizing power loss in the commutation area between the adjacent phases. Constant torque trajectories are considered in incoming and outgoing phase current planes based on nonlinear T-i-theta curves obtained from experimental measurements. Optimum points on constant torque trajectories are selected by improving drive efficiency and minimizing copper loss in each rotor position. A novel analytic invertible function is introduced to express phase torque based on rotor position and its corresponding phase current. The optimization problem is solved by the proposed torque function, and optimum torque sharing functions are derived. A modification method is also introduced to enhance the torque ripple-free region based on simple logic rules. Compared with conventional torque sharing functions, the resultant reference current from the proposed method has less peak and effective values and exhibits lower copper loss. Experimental and simulation results from a four-phase 4 KW 8/6 SRM validate the effectiveness of the proposed method.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.206-213
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• 2012

This study analyzed on the effect worker's organizational citizenship behaviors of vision sharing and values congruence in social enterprise. Analysis results are as follows: the higher the degree of match value of worker and organization, organization's vision have on active organizational citizenship behaviors in social enterprise. And, non-profit organization, full-time employee and Non-disadvantaged are actively organizational citizenship behaviors. Social enterprises's purpose are to solve the social problem in communities and creating the jobs for the vulnerable. Therefore, the administrator of social enterprise strive to share the vision of the organization with worker, and should pay more effort in the selection process for selecting the worker that matches with organization's value.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.10
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• pp.1005-1019
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• 2014

In this paper, we proposed the frequency candidates band for the spectrum sharing through researching and analyzing the current status of the policy and the economic values which is actively conducted on the United States and Europe. To this end, we investigated to the status and problems with the frequency reallocation and arrangement in respond to the current frequency demand. To solve these frequency reallocation and arrangement method problems, we introduce to the concept and current status of policy for the frequency method progress by advanced countries mainly. Also the results of the economic value analysis introduced in terms of the operators. In addition, we proposed the assessment terms and criteria for the selection of frequency candidates band through joint research and analysis results.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.28-34
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• 2021

Internet Service Providers (ISPs) constantly endeavor to resolve network congestion, in order to provide fast and cheap services to the customers. This study suggests two models based on Markov chain, using three and four access attempts to complete the call. It involves a comparative study of four models to check the relationship between Internet Access sharing traffic, and the possibility of network jamming. The first model is a Markov chain, based on call-by-call attempt, whereas the second is based on two attempts. Models III&IV suggested by the authors are based on the assumption of three and four attempts. The assessment reveals that sometimes by increasing the number of attempts for the same operator, the chances for the customers to complete the call, is also increased due to blocking probabilities. Three and four attempts express the actual relationship between traffic sharing and blocking probability based on Markov using MATLAB tools with initial probability values. The study reflects shouting results compared to I&II models using one and two attempts. The success ratio of the first model is 84.5%, and that of the second is 90.6% to complete the call, whereas models using three and four attempts have 94.95% and 95.12% respectively to complete the call.

• Journal of Distribution Science
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• v.15 no.2
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• pp.59-68
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• 2017

Purpose - The year 2016 marks 20 years since the opening of Korean distribution market in 1996. After this opening, the domestic market expanded and modernized, and has grown to become an advanced distribution market with a greater range of consumer choices. On the other hand, traditional markets have waned and their management has become worse. However, traditional markets do not have economic value alone. This study examines the effects of social value in traditional market such as the value of Cultural Tourism and the value of Sharing Community with Traditional Market on Satisfaction, Loyalty and Place Attachment of the residents. Research design, data and methodology - A questionnaire was organized for this study after a hypothesis was set based on theoretical background. Verification of the hypothesis was undertaken by statistically analyzing questionnaire responses. Personal interviews were performed for this study, and a total of 300 responses were collected, of which 228 responses (76%) were from women. The survey coverage was divided into 10 regions ranging from metropolitan areas to the provincial level, and the age groups were divided into 30s to 60s to ensure diversity of the area and age. Results - To summarize the study results, through verification of the hypothesis in terms of meaningful influence, it appears the values of Cultural Tourism to Satisfaction and Loyalty are supported. On the other hand, the value of Sharing Community is only supported for Satisfaction. It appears that Satisfaction to Loyalty and Loyalty to Place Attachment are meaningful effects. The mediator effect was also reconciled through satisfaction and loyalty. Loyalty was analyzed in terms of mediating the effect of satisfaction on place attachment. Conclusions - It is noted in this study that government support is required to preserve traditional markets and renewal program. Community requires multilateral communication and the formation of effective relationships. In contrast to the economic value emphasized by large retailers, the empirical analysis of the non-economic effects of traditional markets has presented the significance of socio-cultural values in traditional markets. In the future, socio-cultural values and economic values should be integrated into more empirical studies through mutual comparison. Investigating the increase and decrease of social value in traditional markets will help the future formulation in government policy.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.166-169
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• 2003

Reinforcement learning if a kind of machine learning. It aims to adapt an agent to a given environment with a clue to a reward and a penalty. Q-learning [8] that is a representative reinforcement learning system treats a reward and a penalty at the same time. There is a problem how to decide an appropriate reward and penalty values. We know the Penalty Avoiding Rational Policy Making algorithm (PARP) [4] and the Penalty Avoiding Profit Sharing (PAPS) [2] as reinforcement learning systems to treat a reward and a penalty independently. though PAPS is a descendant algorithm of PARP, both PARP and PAPS tend to learn a local optimal policy. To overcome it, ion this paper, we propose the Multi Best method (MB) that is PAPS with the multi-start method[5]. MB selects the best policy in several policies that are learned by PAPS agents. By applying PS, PAPS and MB to a soccer game environment based on the SoccerBots[9], we show that MB is the best solution for the soccer game environment.

• Communications of the Korean Mathematical Society
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• v.33 no.2
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• pp.495-505
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• 2018

The uniqueness problems on entire functions sharing at least two values with their derivatives or linear differential polynomials have been studied and many results on this topic have been obtained. In this paper, we study an entire function f(z) that shares a nonzero polynomial a(z) with $f^{(1)}(z)$, together with its linear differential polynomials of the form: $L=L(f)=a_1(z)f^{(1)}(z)+a_2(z)f^{(2)}(z)+{\cdots}+a_n(z)f^{(n)}(z)$, where the coefficients $a_k(z)(k=1,2,{\ldots},n)$ are rational functions and $a_n(z){\not{\equiv}}0$.

• Bulletin of the Korean Mathematical Society
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• v.50 no.3
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• pp.731-745
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• 2013

In this paper, we investigate uniqueness problems of certain types of $q$-difference polynomials, which improve some results in [20]. However, our proof is different from that in [20]. Moreover, we obtain a uniqueness result in the case where $q$-differences of two entire functions share values as well. This research also shows that there exist two sets, such that for a zero-order non-constant meromorphic function $f$ and a non-zero complex constant $q$, $E(S_j,f)=E(S_j,{\Delta}_qf)$ for $j=1,2$ imply $f(z)=t{\Delta}_qf$, where $t^n=1$. This gives a partial answer to a question of Gross concerning a zero order meromorphic function $f(z)$ and $t{\Delta}_qf$.

• Kyungpook Mathematical Journal
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• v.55 no.2
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• pp.411-427
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• 2015

In this article, we main study the uniqueness problem of meromorphic function which difference polynomials sharing common values. We consider the entire function $(f^n(f^m-1)\prod_{j=1}^{s}f(z+c_j)^{{\mu}j})^{(k)}$ and the meromorphic function $f^n(f^m-1)\prod_{j=1}^{s}f(z+c_j)^{{\mu}j}$ to get the main results which extend Theorem 1.1 in paper[5] and theorem 1.4 in paper[6].

• Kyungpook Mathematical Journal
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• v.49 no.2
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• pp.235-243
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• 2009

In this paper, we deal with the problem of uniqueness of meromorphic functions that share two small functions with their derivatives, and obtain the following result which improves a result of Yao and Li: Let f(z) be a nonconstant meromorphic function, k > 5 be an integer. If f(z) and g(z) = $a_1(z)f(z)+a_2(z)f^{(k)}(z)$ share the value 0 CM, and share b(z) IM, $\overline{N}_E(r,f=0=F^{(k)})=S(r)$, f${\equiv}$g, where $a_1(z)$, $a_2(z)$ and b(z) are small functions of f(z).