• Title/Summary/Keyword: hybrid systems

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An Efficient Hybrid Anti-collision Method in RFID systems (RFID 시스템에서 Hybrid 방식을 이용한 효율적인 충돌 회피 기법)

  • Shin, Song-Yong;Hwang, Gyung-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.8
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    • pp.1619-1624
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    • 2012
  • If multiple Tags in the RFID System transmit their IDs to the Reader at the same time, tag identification time is delayed due to collisions. Therefore, to reduce the reader's identification time, an efficient anti-collision technology is needed. In this paper, we propose a hybrid anti-collision method based on the QT and DFSA. Then, the performances of proposed method are compared with the existing method through extensive simulations.

Verification of Hybrid Real Time HVDC Simulator in Cheju-Haenam HVDC System

  • Yang Byeong-Mo;Kim Chan-Ki;Jung Gil-Jo;Moon Young-Hyun
    • Journal of Electrical Engineering and Technology
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    • v.1 no.1
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    • pp.23-27
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    • 2006
  • In this paper a Hybrid Real Time HVDC Simulator fur both operator Training and Researching in the Cheju-Haenam HVDC System is proposed and its performance is studied by means of RTDS (Real Time Digital Simulator), EMTDC (Electro-Magnetic Transients system for DC), PSS/E (Power System Simulator for Engineering), and experienced scenarios. The objective of this paper is to represent the strategy in development for KEPCO's hybrid HVDC simulator for the Cheju-Haenam HVDC system. This simulator consists of two DC stations, DC cables, external digital/analog controllers, monitoring systems and control desk for education, and AC networks. Its suitability for operator's education is tested during startup/shutdown and normal state operations. Dynamic performances of it are also verified.

Effect of the Hydrophobicity of Hybrid Gate Dielectrics on a ZnO Thin Film Transistor

  • Choi, Woon-Seop;Kim, Se-Hyun
    • Transactions on Electrical and Electronic Materials
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    • v.11 no.6
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    • pp.257-260
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    • 2010
  • Zinc oxide (ZnO) bottom-contact thin-film transistors (TFTs) were prepared by the use of injector type atomic layer deposition. Two hybrid gate oxide systems of different polarity polymers with silicon oxide were examined with the aim of improving the properties of the transistors. The mobility and threshold voltage of a ZnO TFT with a poly(4-dimethylsilyl styrene) (Si-PS)/silicon oxide hybrid gate dielectric had values of 0.41 $cm^2/Vs$ and 24.4 V, and for polyimide/silicon oxide these values were 0.41 $cm^2/Vs$ and 24.4 V, respectively. The good hysteresis property was obtained with the dielectric of hydrophobicity. The solid output saturation behavior of ZnO TFTs was demonstrated with a $10^6$ on-off ratio.

Development of the Pneumatic Service Robot with a Hybrid Type (하이브리드형의 공압 서비스 로봇의 개발)

  • Choi, Cheol-U;Choi, Hyeun-Seok;Han, Chang-Soo
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.686-691
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    • 2001
  • In this paper, the pneumatic service robot with a hybrid type is developed. A pneumatic has the advantage of good compliance, high payload-to-weight and payload-to-volume ratios, high speed and force capabilities. Using pneumatic actuators which have low stiffness, the service robot can guarantee safety. By suggesting a new serial-parallel hybrid type for the service robot which separates into positioning motion and orienting motion, we can achieve large workspace and high strength-to-moving-weight ratio at the same time. A sliding mode controller can be designed for tracking the desired output using the Lyapunov stability theory and structural properties of pneumatic servo systems. Through many experiments of circular trajectory, the pneumatic service robot is evaluated and verified.

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Active Page Replacement Policy for DRAM & PCM Hybrid Memory System (DRAM&PCM 하이브리드 메모리 시스템을 위한 능동적 페이지 교체 정책)

  • Jung, Bo-Sung;Lee, Jung-Hoon
    • IEMEK Journal of Embedded Systems and Applications
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    • v.13 no.5
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    • pp.261-268
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    • 2018
  • Phase Change Memory(PCM) with low power consumption and high integration attracts attention as a next generation nonvolatile memory replacing DRAM. However, there is a problem that PCM has long latency and high energy consumption due to the writing operation. The PCM & DRAM hybrid memory structure is a fruitful structure that can overcome the disadvantages of such PCM. However, the page replacement algorithm is important, because these structures use two memory of different characteristics. The purpose of this document is to effectively manage pages that can be referenced in memory, taking into account the characteristics of DRAM and PCM. In order to manage these pages, this paper proposes an page replacement algorithm based on frequently accessed and recently paged. According to our simulation, the proposed algorithm for the DRAM&PCM hybrid can reduce the energy-delay product by around 10%, compared with Clock-DWF and CLOCK-HM.

Hybrid Fuzzy Control Systems with Look-Up Table for Good Performance (성능개선을 위한 룩업테이블 하이브리드 퍼지제어 시스템)

  • Lee, Pyeong-Gi
    • Journal of the Korean Society of Industry Convergence
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    • v.19 no.3
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    • pp.101-108
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    • 2016
  • I propose a hybrid fuzzy controller with a look-up table to improve the performance of the FARMA(Fuzzy Auto-regressive Moving Average) fuzzy controller. The hybrid structure of the proposed method is composed of a fuzzy controller with a look-up table of the PD type and the FARMA fuzzy controller. The proposed method improves poor performance due to the lack of I/O data to calculate predictive output and shows robust performance over the FARMA fuzzy controller when a incorrect Dmax value is selected by trial and error. I executed some computer simulations on the regulation problem of an inverted pendulum system and compared the results with those of the FARMA fuzzy controller.

High Performance PCM&DRAM Hybrid Memory System (고성능 PCM&DRAM 하이브리드 메모리 시스템)

  • Jung, Bo-Sung;Lee, Jung-Hoon
    • IEMEK Journal of Embedded Systems and Applications
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    • v.11 no.2
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    • pp.117-123
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    • 2016
  • In general, PCM (Phase Change Memory) is unsuitable as a main memory because it has limitations: high read/write latency and low endurance. However, the DRAM&PCM hybrid memory with the same level is one of the effective structures for a next generation main memory because it can utilize an advantage of both DRAM and PCM. Therefore, it needs an effective page management method for exploiting each memory characteristics dynamically and adaptively. So we aim reducing an access time and write count of PCM by using an effective page replacement. According to our simulation, the proposed algorithm for the DRAM&PCM hybrid can reduce the PCM access count by around 60% and the PCM write count by 42% given the same PCM size, compared with Clock-DWF algorithm.

A Fundamental study on the Optimum Performance of the Architectural Hybrid Water-proofing Systems (건축 복합방수공법의 최적성능에 관한 기초연구)

  • Lim, Seok Ho;Lim, Byung Hoon
    • Journal of the Korea Institute of Building Construction
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    • v.5 no.2 s.16
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    • pp.123-130
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    • 2005
  • The purpose of this study is to present the optimum performance of hybrid waterproofing technology, which is including material and construction method. Recently, Hybrid waterproofing technology is developed little by little in KOREA. But there is not any other criterion of performance and evaluation of this technology. So, It is needed that appropriate performance items is are settled urgently. This paper were obtained by the SPSS analysis. In this study the safety factor are more important performance of building waterproofing materials than durability comfortability and productivity. And results of this analysis showed that (1) safety performance consists of Fatigue resistance, Crack Control performance deterioration Processing of tensile performance, Compressive Strength test (2) comfortability performance consists of watertightness, bond performance (3) persistency performance consists of abrasion resistance, tensile performance, flexural strength (4) productivity performance consists of dimension, unit space weight.

A Review on New Non-hybrid Technologies to Improve Energy Efficiency of Construction Machineries (건설기계의 에너지 효율 제고를 위한 비-하이브리드 신기술에 관한 리뷰)

  • Joh, Joong Seon
    • Journal of Drive and Control
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    • v.13 no.3
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    • pp.53-66
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    • 2016
  • New non-hybrid approaches to improve energy efficiency of construction machineries are reviewed in this paper. Hydraulic systems are classified into four classes according to Backe's classification and commercially promising new technologies are carefully chosen in each class. IMV, 3-Line CPR, Closed Circuit Displacement Control of Differential Cylinder, and Throttle-less Secondary Control are chosen as representative non-hybrid new technologies. Key principle of each technology is explained and representative references which run through each technology are selected. Advantages and weaknesses of each technology are discussed and compared from the view point of construction machinery manufacturers.

The Energy Saving and the Reproducibility of Highly-Efficient Injection Molding Machine (고효율 사출성형기의 에너지 절감 및 성형 재현성 연구)

  • Hwang, C.J.;Kim, J.S.;Jeong, C.;An, H.J.;Heo, Y.M.;Kim, J.D.;Yoon, K.H.
    • Transactions of Materials Processing
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    • v.17 no.8
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    • pp.662-667
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    • 2008
  • Because of steep rise of international energy cost in recent years, high efficiency has been emphasized in energy policy. As far as injection molding machine is concerned, hybrid method using hydraulic and electric systems became the key to this energy saving. The energy saving and molding reproducibility of hybrid injection molding process were shown experimentally. The power consumption of hybrid injection molding machine is reduced to 38% as compared with that of hydraulic machine. Furthermore, the molding reproducibility was shown for both methods.