• Title/Summary/Keyword: Evolve

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Cognitive UWB-OFDM: Pushing Ultra-Wideband Beyond Its Limit via Opportunistic Spectrum Usage

  • Arslan Huseyin;Sahin Mustafa E.
    • Journal of Communications and Networks
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    • v.8 no.2
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    • pp.151-157
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    • 2006
  • In a continuously expanding wireless world, the number of radio systems increases every day and efficient spectrum usage becomes a more significant requirement. Ultra-wideband (UWB) and cognitive radio are two exciting technologies that offer new approaches to the spectrum usage. The main objective of this paper is to shed the first light on the marriage of these two important approaches. The strength of orthogonal frequency division multiplexing (OFDM) based UWB in co-existing with licensed systems is investigated. The opportunity concept is defined, and the requirements of the opportunistic spectrum usage are explained. It is proposed to take the UWB-OFDM from the current underlay implementation, and evolve it to a combined underlay and opportunistic spectrum usage technology, leading to cognitive UWB-OFDM. This way, we aim at making UWB more competitive in the wireless market with extended range, higher capacity, better performance, and a wide variety of applications.

Evolutionary Design of Fuzzy Rule Base for Modeling and Control (비선형 시스템 모델링 및 제어를 위한 퍼지 규칙기반의 진화 설계)

  • Lee, Chang-Hoon
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.12
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    • pp.566-574
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    • 2001
  • In designing fuzzy models and controllers, we encounter a major difficulty in the identification f an optimized fuzzy rule base, which is traditionally achieved by a tedious trial-and-error process. This paper presents an approach to the evolutionary design of an optimal fuzzy rule base for modeling and control. Evolutionary programming is used to simultaneously evolve the structure and the parameter of fuzzy rule base for a given task. To check the effectiveness of the suggested approach, four numerical examples are examined. The performance of the identified fuzzy rule bases is demonstrated.

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Simple Recursive Approach for Detecting Spatial Clusters

  • Kim Jeongjin;Chung Younshik;Ma Sungjoon;Yang Tae Young
    • Communications for Statistical Applications and Methods
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    • v.12 no.1
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    • pp.207-216
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    • 2005
  • A binary segmentation procedure is a simple recursive approach to detect clusters and provide inferences for the study space when the shape of the clusters and the number of clusters are unknown. The procedure involves a sequence of nested hypothesis tests of a single cluster versus a pair of distinct clusters. The size and the shape of the clusters evolve as the procedure proceeds. The procedure allows for various growth clusters and for arbitrary baseline densities which govern the form of the hypothesis tests. A real tree data is used to highlight the procedure.

Trends in and Forecasting of AI-Based Radio Wave Technology (전파기술의 AI 적용 동향 및 전망)

  • Jeon, S.I.;Kim, Y.;Kim, B.C.;You, S.J.;Lee, J.;Byun, W.J.
    • Electronics and Telecommunications Trends
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    • v.35 no.5
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    • pp.69-82
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    • 2020
  • In many technologies, artificial intelligence (AI) is becoming an important topic for areas based on the field of big data. However, applied AI cases and the research status of radio wave technology are not widely known to the public. The spread of AI to other areas is being followed by radio wave technologies, and much effort is being taken to evolve it into intelligent radio wave technologies in the future. This paper presents the recent areas of interest in radio wave technology, such as spectral sharing, illegal spectrum monitoring, radar detection, radio wave medical imaging, and channel modeling; examines the requirements for applying AI; and describes the applied cases, research trends, and standardization efforts that apply AI technology to them. On this basis, we will discuss the prospects of AI application to the expected radio wave technology of the future.

A motion capture and mimic system for intelligent interactions (지능 접속을 위한 인체 운동 포착 및 재현 시스템)

  • Yoon, Joong-Sun
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.5
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    • pp.585-592
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    • 1999
  • A new paradigm of technology, based on the overall interactions of technology, human and environment, is explored. History of technology and machines is reviewed in terms of the interactions of human and machines. Two main concepts of intelligent interactions proposed, holism and embodiment, are based on the interactions of machines and human through human body : Korperlichkeit ( corporeality). Human body movements are the result of long periods of evolution and, thus, are very optimized motions. Complicated and flexible motions could be easily achieved by mimicking human body movements. Motion capture and mimic systems based on the electromagnetic, visual, and gyroscopic type trackers, are being implemented to demonstrate these concepts. Also, various motion mappings are investigated on these interactive systems. By exploring a new paradigm of technology through Korperlichkeit, an oriental view of technology as relativities may evolve to embrace the limitations of western view of machines as an absolute independent form.

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Pareto RBF network ensemble using multi-objective evolutionary computation

  • Kondo, Nobuhiko;Hatanaka, Toshiharu;Uosaki, Katsuji
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.925-930
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    • 2005
  • In this paper, evolutionary multi-objective selection method of RBF networks structure is considered. The candidates of RBF network structure are encoded into the chromosomes in GAs. Then, they evolve toward Pareto-optimal front defined by several objective functions concerning with model accuracy and model complexity. An ensemble network constructed by such Pareto-optimal models is also considered in this paper. Some numerical simulation results indicate that the ensemble network is much robust for the case of existence of outliers or lack of data, than one selected in the sense of information criteria.

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The Evolving Role of Mileage in e-Business: Private e-Money Perspective (e-비즈니스에서 마일리지의 새로운 역할 : 사적 전자화폐 관점)

  • Park, Seung-Bong;Han, Jae-Min
    • The Journal of Information Systems
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    • v.13 no.2
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    • pp.119-134
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    • 2004
  • This research investigates the rising new role of mileage system as private e-money in a exploratory study. The key research questions are "How does mileage system evolve with expansion of e-business and what are the cases for real experiences in 'money-like' mileage and their implications?" This research focuses on the proposition that mileage points created in commercial transactions as a royalty program are observed to serve a new role as payment tool. In an attempt to identify factors that determine mileage system as private money, we employ three factors: confidence, transaction cost, and monetary freedom. Also, this research proposes a direction for further research and follow-up studies to establish legal and institutional issues and the relevant architecture, all of which are essential elements to make the mileage points global money with a certain trade ratio in the near future.

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Improving Flexibility of External Data Exchange in Count-fire Operation System by Adapting Dynamic Parser Software (동적 구문처리기 소프트웨어 적용을 통한 대화력전 수행체계 연동의 유연성 향상 방안)

  • Hong, Won-Eui
    • Journal of the Korea Institute of Military Science and Technology
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    • v.11 no.1
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    • pp.51-56
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    • 2008
  • The counter-fire operation system performs its mission exchanging information with other related systems such as command & control systems and military information systems. In the process of exchanging information, the counter-fire operation system uses a type of data message which contains exchange data information in the format of KMTF. The requirement of data exchange of count-fire operation will continue to evolve. But the EDX(External Data eXchange) configuration item of the current counter-fire operation system can not effectively cope with the variation of data exchange requirements due to its fixed software structure. In the paper, a solution for improving flexibility of external data exchange in counter-fire operation system is proposed.

Unlicensed Spectrum as a Source of Innovation Applicability in the Republic of Kazakhstan

  • Abishev, Olzhas;Lee, Joon-Won
    • Journal of information and communication convergence engineering
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    • v.7 no.2
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    • pp.87-91
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    • 2009
  • Over the past several years both licensed and unlicensed services and devices have enjoyed extensive growth in the wireless marketplace. In some urban areas in the Kazakhstan, the penetration rate of licensed cellular and PCS services is more than 60%. Similarly, the use of unlicensed wireless local area network technologies has grown significantly as these systems have been deployed in homes, offices, and 'hot spots' in restaurants, hotels, public meeting areas, etc. As more services are wirelessly enabled and as technologies continue to evolve, the demand for new spectrum for commercial services will also continue to increase. Thus, the appropriate regulatory models for future spectrum allocations will continue to be debated throughout the wireless industry.

HTS Nested magnet wound with 12 mm GdBCO tape and 4.4 mm YBCO tape

  • Kang, Myunghun;Ku, Myunghwan;Cha, Gueesoo;Lim, Hyoungwoo
    • Progress in Superconductivity and Cryogenics
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    • v.17 no.2
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    • pp.50-53
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    • 2015
  • The properties of High Temperature Superconducting (HTS) tapes are progressing, as HTS tapes evolve from 1st generation to 2nd generation. This paper presents design and construction of a 2nd generation HTS magnet consisting of two nested GdBCO and YBCO pancake coils. Two HTS tapes of different widths were used to wind the HTS nested magnet. Considering that a higher magnetic field is applied to the inner magnet than to the outer magnet, 12 mm GdBCO tape was used for winding the inner magnet, which consisted of four single pancake windings. Eight double pancake windings wound with 4.4 mm YBCO tapes were used for the outer magnet. The test results show that the central magnetic field of the HTS nested magnet was 920 mT. The measured critical currents of the inner and outer magnet at 77K were 80.8 A and 32.6 A, respectively.