• Title/Summary/Keyword: hybrid techniques

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Hybrid State Space Self-Tuning Fuzzy Controller with Dual-Rate Sampling

  • Kwon, Oh-Kook;Joo, Young-Hoon;Park, Jin-Bae;L. S. Shieh
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.244-249
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    • 1998
  • In this paper, the hybrid state space self-tuning control technique Is studied within the framework of fuzzy systems and dual-rate sampling control theory. We show that fuzzy modeling techniques can be used to formulate chaotic dynamical systems. Then, we develop the hybrid state space self-tuning fuzzy control techniques with dual-rate sampling for digital control of chaotic systems. An equivalent fast-rate discrete-time state-space model of the continuous-time system is constructed by using fuzzy inference systems. To obtain the continuous-time optimal state feedback gains, the constructed discrete-time fuzzy system is converted into a continuous-time system. The developed optimal continuous-time control law is then convened into an equivalent slow-rate digital control law using the proposed digital redesign method. The proposed technique enables us to systematically and effective]y carry out framework for modeling and control of chaotic systems. The proposed method has been successfully applied for controlling the chaotic trajectories of Chua's circuit.

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Solar power and desalination plant for copper industry: improvised techniques

  • Sankar, D.;Deepa, N.;Rajagopal, S.;Karthik, K.M.
    • Advances in Energy Research
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    • v.3 no.1
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    • pp.59-70
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    • 2015
  • In India, continuous production of electricity and sweet/potable water from Solar power and desalination plant plays a major role in the industries. Particularly in Copper industry, Solar power adopts Solar field collector combined with thermal storage system and steam Boiler, Turbine & Generator (BTG) for electricity production and desalination plant adopts Reverse osmosis (RO) for sweet/potable water production which cannot be used for long hours of power generation and consistency of energy supply for industrial processes and power generation cannot be ensured. This paper presents an overview of enhanced technology for Solar power and Desalination plant for Copper industry making it continuous production of electricity and sweet/potable water. The conventional technology can be replaced with this proposed technique in the existing and upcoming industries.

Brief Overview on Design Techniques and Architectures of SAR ADCs

  • Park, Kunwoo;Chang, Dong-Jin;Ryu, Seung-Tak
    • Journal of Semiconductor Engineering
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    • v.2 no.1
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    • pp.99-108
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    • 2021
  • Successive Approximation Register (SAR) Analog-to-Digital Converters (ADC) seem to become the hottest ADC architecture during the past decade in implementing energy-efficient high performance ADCs. In this overview, we will review what kind of circuit techniques and architectural advances have contributed to place the SAR ADC architecture at its current position, beginning from a single SAR ADC and moving to various hybrid architectures. At the end of this overview, a recently reported compact and high-speed SAR-Flash ADC is introduced as one design example of SAR-based hybrid ADC architecture.

Analysis of Hybrid Emulsion Surfaces by the Phase Lag Mapping Atomic Force Microscopy (위상지연 원자간력 현미경법에 의한 혼성 에멀젼 표면의 분석)

  • Han, Sang-Hoon;Kim, Jong-Min;Park, Dong-Won
    • Applied Chemistry for Engineering
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    • v.17 no.4
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    • pp.381-385
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    • 2006
  • We applied a new analyzing technique for the polyurethane acrylate hybrid emulsion sample composed of polyurethane resin and acrylate resin using the phase-lag mapping techniques of atomic force microscopy. For the analysis, we synthesized similarly sized pure polyurethane dispersion and acrylate emulsion particles, which were used for measuring the standard phase-lag intensities for each material. Based on these signal intensity, we could discriminate acryl particle in the polyurethane dispersion matrix with the resolution of a few tens of nanometers. Thus, the techniques show a new possibility in the analysis of the organic two-phase particles, and we believe the techniques are helpful to design organic particles.

Comparative Study on the Radiation Techniques for the Problem of Floating Body Motion with Forward Speed (전진 속도를 가지는 부유체 운동 문제에 대한 방사기법 비교 연구)

  • Oh, Seunghoon
    • Journal of the Society of Naval Architects of Korea
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    • v.56 no.5
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    • pp.396-409
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    • 2019
  • In this paper, a comparative study on the radiation techniques for the motion analysis of the three dimensional floating structure with the forward speed was carried out. The Sommerfeld radiation condition, the damping technique, and the point shift technique were used for the comparative study. Radiated wave patterns and hydrodynamic coefficients of the heave motion of floating structure with the forward speed were compared and analyzed. The characteristics and limitations of each radiation technique were analyzed through the calculation results. To overcome the limitations of conventional radiation techniques, the hybrid radiation technique combining the Sommerfeld radiation condition with the damping technique was proposed. It is confirmed that the proposed method, the Hybrid radiation technique, improves the limitation of the speed range and the dissipation of the wave of the conventional radiation technique. The motion analysis code of the three dimensional floating structure with the forward speed based on the Rankine source method with hybrid radiation technique was developed. In order to validate the developed code, hydrodynamic analyses were carried and compared with published experiments.

Fabrication of Hybrid Composite Plates with an Active Frequency Selective Surface

  • Seo, Yun-Seok;Chun, Heoung-Jae;Hong, Ic-Pyo;Park, Young-Bae;Kim, Yoon-Jae
    • Composites Research
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    • v.30 no.5
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    • pp.273-279
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    • 2017
  • This paper describes the fabrication techniques and analysis of hybrid composite plates with an active frequency selective surface (FSS). For fabricating hybrid composite plate with active FSS, an active FSS with a resonance frequency located in the C band can obtained using varactor diodes. The hybrid composite plate was first designed and simulated to determine its electromagnetic properties using the commercial software HFSS. After simulation, active FSSs and hybrid composite plates were fabricated by mounting with varactor diodes. After fabrication, free space measurement was used to determine the electromagnetic properties of active FSS and the hybrid composite plates. The simulation and experimental results were in good agreement.

Hybrid Model Based Intruder Detection System to Prevent Users from Cyber Attacks

  • Singh, Devendra Kumar;Shrivastava, Manish
    • International Journal of Computer Science & Network Security
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    • v.21 no.4
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    • pp.272-276
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    • 2021
  • Presently, Online / Offline Users are facing cyber attacks every day. These cyber attacks affect user's performance, resources and various daily activities. Due to this critical situation, attention must be given to prevent such users through cyber attacks. The objective of this research paper is to improve the IDS systems by using machine learning approach to develop a hybrid model which controls the cyber attacks. This Hybrid model uses the available KDD 1999 intrusion detection dataset. In first step, Hybrid Model performs feature optimization by reducing the unimportant features of the dataset through decision tree, support vector machine, genetic algorithm, particle swarm optimization and principal component analysis techniques. In second step, Hybrid Model will find out the minimum number of features to point out accurate detection of cyber attacks. This hybrid model was developed by using machine learning algorithms like PSO, GA and ELM, which trained the system with available data to perform the predictions. The Hybrid Model had an accuracy of 99.94%, which states that it may be highly useful to prevent the users from cyber attacks.

Development of Web-based Intelligent Recommender Systems using Advanced Data Mining Techniques (개선된 데이터 마이닝 기술에 의한 웹 기반 지능형 추천시스템 구축)

  • Kim Kyoung-Jae;Ahn Hyunchul
    • Journal of Information Technology Applications and Management
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    • v.12 no.3
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    • pp.41-56
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    • 2005
  • Product recommender system is one of the most popular techniques for customer relationship management. In addition, collaborative filtering (CF) has been known to be one of the most successful recommendation techniques in product recommender systems. However, CF has some limitations such as sparsity and scalability problems. This study proposes hybrid cluster analysis and case-based reasoning (CBR) to address these problems. CBR may relieve the sparsity problem because it recommends products using customer profile and transaction data, but it may still give rise to scalability problem. Thus, this study uses cluster analysis to reduce search space prior to CBR for scalability Problem. For cluster analysis, this study employs hybrid genetic and K-Means algorithms to avoid possibility of convergence in local minima of typical cluster analyses. This study also develops a Web-based prototype system to test the superiority of the proposed model.

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System Level ESD Analysis - A Comprehensive Review II on ESD Coupling Analysis Techniques

  • Yousaf, Jawad;Lee, Hosang;Nah, Wansoo
    • Journal of Electrical Engineering and Technology
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    • v.13 no.5
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    • pp.2033-2044
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    • 2018
  • This study presents states-of-the art overview of the system level electrostatic discharge (ESD) analysis and testing. After brief description of ESD compliance standards and ESD coupling mechanisms, the study provides an in-depth review and comparison of the various techniques for the system level ESD coupling analysis using time and frequency domain techniques, full wave electromagnetic modeling and hybrid modeling. The methods used for improving system level ESD testing using troubleshooting and determining the root causes of soft failures, the optimization of ESD testing and the countermeasures to mitigate ESD problems are also discussed.

Evaluation of Subtractive Clustering based Adaptive Neuro-Fuzzy Inference System with Fuzzy C-Means based ANFIS System in Diagnosis of Alzheimer

  • Kour, Haneet;Manhas, Jatinder;Sharma, Vinod
    • Journal of Multimedia Information System
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    • v.6 no.2
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    • pp.87-90
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    • 2019
  • Machine learning techniques have been applied in almost all the domains of human life to aid and enhance the problem solving capabilities of the system. The field of medical science has improved to a greater extent with the advent and application of these techniques. Efficient expert systems using various soft computing techniques like artificial neural network, Fuzzy Logic, Genetic algorithm, Hybrid system, etc. are being developed to equip medical practitioner with better and effective diagnosing capabilities. In this paper, a comparative study to evaluate the predictive performance of subtractive clustering based ANFIS hybrid system (SCANFIS) with Fuzzy C-Means (FCM) based ANFIS system (FCMANFIS) for Alzheimer disease (AD) has been taken. To evaluate the performance of these two systems, three parameters i.e. root mean square error (RMSE), prediction accuracy and precision are implemented. Experimental results demonstrated that the FCMANFIS model produce better results when compared to SCANFIS model in predictive analysis of Alzheimer disease (AD).