• Title/Summary/Keyword: Network theory

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Intellignce Modeling of Nonlinear Process System Using Fuzzy Neyral Networks-based Structure (퍼지-뉴럴네트워크 구조에 의한 비선형 공정시스템의 지능형 모델링)

  • 오성권;노석범;남궁문
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.4
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    • pp.41-55
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    • 1995
  • In this paper, an optimal idenfication method using fuzzy-neural networks is proposed for modeling of nonlinear complex systems. The proposed fuzzy-neural modeling implements system structure and parameter identification using the intelligent schemes together wlth optimization theory, linguistic fuzzy implication rules, and neural networks(NNs) from input and output data of processes. Inference type for this fuzzy-neural modeling is presented as simplified inference. To obtain optimal model, the learning rates and momentum coefficients of fuzzy-neural networks(FNNs) are tuned automatically using improved modified complex method and modified learning algorithm. For the purpose of its application to nonlinear processes, data for route choice of traffic problems and those for activateti sluge process of sewage treatment system are used for the purpose of evaluating the performance of the proposed fuzzy-neural network modeling. The results show that the proposed method can produce the intelligence model with higher accuracy than other works achieved previously.

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The Effect of Teaching Experience in After-School Learning Programs: Implication for the Development of Mathematics Teacher Education Program (대학생 교사제의 효과 분석: 사범대학 수학교사교육 프로그램 개발을 위한 제언)

  • Ju Mi-Kyung
    • The Mathematical Education
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    • v.45 no.3 s.114
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    • pp.295-313
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    • 2006
  • University teacher education programs have sought for ways of how to improve student teaching in order to supply mathematics teachers with practical theory to achieve the goals of the current educational reform in school mathematics. In this context, the purpose of this research is to investigate the effect of student teachers' teaching experience in the after-school mathematics programs and the ways of how to develop the after-school learning programs as an effective site for learning to teach based on the inquiry into student teachers' own teaching experience. For the purpose, data were collected through the interviews with the student teachers who had taught after-school mathematics class. In addition, data were collected through survey, class observation, and seminal meetings with the student teachers in order to supplement the findings from the interview analysis. Data analysis focused on the student teachers' experience with teaching in after-school mathematics classes, that is, what and how they had learned as teachers, what kinds of difficulties they encountered in their teaching and supports that they expect to improve their learning through teaching. The analysis shows that the teaching experience in the after-school programs had positively contributed to their development as future mathematics teachers. Specifically, the after-school programs provide the site for learning through teaching at the early stage of teacher education program. The after-school programs provided the students teachers for the opportunity to participate peripherally in educational practice of school. Through the participation, the student teachers developed positive attitudes toward teaching career and became to have more solid ideas about how to teach mathematics. Based on the analysis, this research provides following suggestions concerning how to improve student teaching. First, it is necessary to provide student teachers to participate into the practice of teaching at the early stage of teacher education programs. Second, it is important to give students teacher opportunity to participate in teaching at peripheral and legitimate positions. Finally, it is necessary to construct mentoring networks to support student teachers to move from a peripheral position toward a center of teaching practice.

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Analysis of GMR Phenomenon by Asymmetric Multi-layered Dielectric Gratings (비대칭 다층 유전체 격자구조에 의한 GMR 현상의 분석)

  • Ho, Kwang-Chun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.3
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    • pp.209-214
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    • 2017
  • A plane-wave incident upon asymmetric multi-layered dielectric grating as well as symmetric grating structure generates space harmonics. Selected space harmonics among those harmonics can undergo strong resonance scattering variations known as GMR(guided-mode resonance). In this paper, to clarify these effects, the field propagation and dispersion curve inside the grating region are analyzed by using a rigorous equivalent transmission-line theory(RETT) based on eigenvalue problem. The results show that, at the peak of a scattering resonance, the reflected mode is almost identical to a leaky wave that can be supported by the grating structure. Thus, it confirms to be occurred GMR effect associated with the free-resonant character of leaky waves at asymmetric multi-layered dielectric gratings. Quantitative simulation results illustrating the behavior of typical gratings are given, and the special case of normal incidence is discussed for TE and TM modes.

Impedance Characteristics of Overhead Medium-Voltage Power lines for Power Line Communication (전력선통신을 위한 고압 배전선로의 임피던스 특성)

  • Chun Dong-wan;Park Young-jin;Kim Kwan-ho;Shin Chull-chai
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.11
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    • pp.67-78
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    • 2005
  • In this paper, impedance characteristics of overhead medium-voltage (MV) power line for power line communication (PLC) is analyzed. For analysis, a two-port equivalent network model of MV power lines is derived. By applying the equivalent model and basic transmission line theory, input impedance at the signal induction part is calculated. And also calculated input impedance of power line itself that the medium voltage coupler and coaxial cable effect are removed. For verification, impedance of power lines is measured at a test field for an MV PLC. The results show that impedance of MV power line itself is between $200\;{\Omega}\;and\;300\;{\Omega}$ and converges to a half of their characteristic impedance with increasing frequency. And also measured data is very similar to calculated data.

A study on the natural history projection mapping contents using Gestalt Visual Perception Theory (게슈탈트 시지각 이론을 활용한 자연사 프로젝션 맵핑연구)

  • Park, Ki-Deok;Chung, Jean-Hun
    • Journal of Digital Convergence
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    • v.18 no.5
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    • pp.465-471
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    • 2020
  • This paper aims to maximize the exhibition effect and to emphasize the efficiency of sample information transfer by using the surrealism dephase network technique and beam projection mapping by aesthetically approaching the arrangement of the existing exhibition specimens in the science museum using natural history contents. It presents the limitations of the existing analog natural history sample information transmission in digital form to give viewers interesting and fun and suggests the direction of using digital diorama for sample exhibition.

Effects of Gleditsiae Spina(GS) on the Polycystic Ovary Induced by Estradiol Valerate in Rats (조각자(皂角刺)가 estradiol valerate로 유발된 백서(白鼠)의 다낭성 난소에 미치는 영향)

  • Gu, Hee-Jun;Cho, Sung-Hee
    • The Journal of Korean Obstetrics and Gynecology
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    • v.23 no.2
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    • pp.71-84
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    • 2010
  • Purpose: In the theory of traditional medicine, Glenditsia spina(GS) can resolve carbuncle, relive swelling, dispel wind and destroy parasites. This study was designed to investigate the effects of GS on gene expression of ovarian tissue in polycystic ovary syndrome(PCOS) rats. Methods: In this experiment, female rats injected with a single dose of 2 mg estradiol valerate(EV) and GS was given for 5 weeks. The genetic profile for the effects on ovarian tissue in PCOS rats was measured using microarray technique, and the functional analysis on these genes was conducted. Results: 985 genes were increased in control and restored to normal level in GS group. (B), 733 genes were decreased in control group and restored to normal level in GS group. (F). Metabolic pathways related in B group genes were Graft-versus-host disease, Allograft rejection, Autoimmune thyroid disease, Cytokine-cytokine receptor interaction, Small cell lung cancer, Type I diabetes mellitus. Metabolic pathways related in F group genes were Antigen processing and present, Adipocytokine signalling pathway, Focal adhesion, ECM-receptor interaction, Pancreatic cancer, Notch signalling pathway, Tight junction. The network of total protein interactions was measured using cytoscape program, and some key molecules, such as c-Fos, c-Myc, ABL1 related in B group, MAPK8, RASA1, CALR related in F group that can be used for elucidation of therapeutical mechanism of medicine in future were identified. Conclusion: These results suggest possibility of GS as anti-cancer and anti-hyperplasia drug in PCOS. In addition, the present author also suggests that related mechanisms are involved in suppression of proto-oncogene such as c-Fos, c-Myc and ABL1, and in regulation of cell cycle such as RASA1.

Relay Selection Scheme Based on Quantum Differential Evolution Algorithm in Relay Networks

  • Gao, Hongyuan;Zhang, Shibo;Du, Yanan;Wang, Yu;Diao, Ming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.7
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    • pp.3501-3523
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    • 2017
  • It is a classical integer optimization difficulty to design an optimal selection scheme in cooperative relay networks considering co-channel interference (CCI). In this paper, we solve single-objective and multi-objective relay selection problem. For the single-objective relay selection problem, in order to attain optimal system performance of cooperative relay network, a novel quantum differential evolutionary algorithm (QDEA) is proposed to resolve the optimization difficulty of optimal relay selection, and the proposed optimal relay selection scheme is called as optimal relay selection based on quantum differential evolutionary algorithm (QDEA). The proposed QDEA combines the advantages of quantum computing theory and differential evolutionary algorithm (DEA) to improve exploring and exploiting potency of DEA. So QDEA has the capability to find the optimal relay selection scheme in cooperative relay networks. For the multi-objective relay selection problem, we propose a novel non-dominated sorting quantum differential evolutionary algorithm (NSQDEA) to solve the relay selection problem which considers two objectives. Simulation results indicate that the proposed relay selection scheme based on QDEA is superior to other intelligent relay selection schemes based on differential evolutionary algorithm, artificial bee colony optimization and quantum bee colony optimization in terms of convergence speed and accuracy for the single-objective relay selection problem. Meanwhile, the simulation results also show that the proposed relay selection scheme based on NSQDEA has a good performance on multi-objective relay selection.

Load-Balancing Rendezvous Approach for Mobility-Enabled Adaptive Energy-Efficient Data Collection in WSNs

  • Zhang, Jian;Tang, Jian;Wang, Zhonghui;Wang, Feng;Yu, Gang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.3
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    • pp.1204-1227
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    • 2020
  • The tradeoff between energy conservation and traffic balancing is a dilemma problem in Wireless Sensor Networks (WSNs). By analyzing the intrinsic relationship between cluster properties and long distance transmission energy consumption, we characterize three node sets of the cluster as a theoretical foundation to enhance high performance of WSNs, and propose optimal solutions by introducing rendezvous and Mobile Elements (MEs) to optimize energy consumption for prolonging the lifetime of WSNs. First, we exploit an approximate method based on the transmission distance from the different node to an ME to select suboptimal Rendezvous Point (RP) on the trajectory for ME to collect data. Then, we define data transmission routing sequence and model rendezvous planning for the cluster. In order to achieve optimization of energy consumption, we specifically apply the economic theory called Diminishing Marginal Utility Rule (DMUR) and create the utility function with regard to energy to develop an adaptive energy consumption optimization framework to achieve energy efficiency for data collection. At last, Rendezvous Transmission Algorithm (RTA) is proposed to better tradeoff between energy conservation and traffic balancing. Furthermore, via collaborations among multiple MEs, we design Two-Orbit Back-Propagation Algorithm (TOBPA) which concurrently handles load imbalance phenomenon to improve the efficiency of data collection. The simulation results show that our solutions can improve energy efficiency of the whole network and reduce the energy consumption of sensor nodes, which in turn prolong the lifetime of WSNs.

Comparative Study of Computer Education between UK and Korean Schools (한국과 영국에서의 학교 컴퓨터 교육 비교 연구)

  • Ha, Tai-Hyun
    • The Journal of Korean Association of Computer Education
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    • v.4 no.1
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    • pp.161-174
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    • 2001
  • This study is aimed at putting forward effective methods of computer education for use in schools by comparing the schools of UK and Korea. It shows : 1) a big difference in infrastructure such as H/W and Network, 2) for S/W budget UK teachers have control over their own budget, but not in Korea, 3) government, school, teacher, student, and parent all have the same mind set to promote the use of information communication technology in the UK, but in Korea the government alone drives it with its own policy. At University level, potential computer teachers in the UK are emphasized to practice fields works in schools, but in Korea, the course mainly consists of education theory and pre-teachers get only four weeks field experience. In addition, computer teachers are often those with majors in different fields, but due to the lack of interest in computer education, they are forced into these empty positions. This often leads to conflict between students and teachers because of those teachers who do not have the necessary depth in knowledge of computers.

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The Father's Role and Father-Child Interaction: A Review of Literature (아버지-아동관계에 관한 이론적 고찰 - 아버지의 역할 및 아버지-아동의 상호작용을 중심으로 -)

  • Wui, Yeong Hee
    • Korean Journal of Child Studies
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    • v.4
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    • pp.23-35
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    • 1983
  • The purpose of this study is to systematize the theory of the father-child relationship by analyzing the father's role and father-child interaction. The results of this study are as followings: (1) The oedipal period 3 to 5 years is a critical in development of the father-child relationship. Father absence is assumed in infancy but it is denying because the father participates in Child- rearing activity. (2) The Father's role is symbolized instrumental role traditionally and culturally but it is appropriate that we think the father's role to be androgynous concepts. Instrumental role as well as expressive role is expected to father's role. (3) The role of the father is supplementary mother's role. The father provides economic, emotional support and helps the balanced child- rearing. This indirect role of the father is very important. (4) The father influences child development, and his role is to be sex-role model to contrieve personality internalize moral development. But it is needed more empirical study to clarify father's effects on child development. (5) The amount of time that fathers spend with their children is less than mothers, but it is not assumed that difference of this amount of time do not differently influence to the children. (6) There are much similarity that difference between father-child interaction and mother- child interaction. Qualitative difference in interaction is response style. A responsive style of the father is physical intellectual instructive but mother's is verbal. (7) The effects of the father to a child must be analyzed on dyadic dimension and triadic dimension of family network. In triadic dimension, father influences mother- child relationship, mother to response sensitively, husband-wife relation.

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