• Title/Summary/Keyword: Next Generation PCs

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Design and Simulation of DC/DC Converter for PCS Handset (PCS 단말기용 DC/DC 컨버터의 회로설계 및 시뮬레이션)

  • 김동욱;조신희;김남영;장동석;구기덕
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.739-742
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    • 1999
  • This study is to increase capability of the DC/DC converter (for PCS) in miniaturizing, stabilizing by locating an inductor with the structure of multi layer on to the glass/ceramic circuit board. When the DC/DC converter is stimulated. the characteristic operation of PWM switching circuit, losses. output power to input power, stability, efficiency and interfaces inside of control circuit and convener circuit are to be distinguished. The process would make it able to develop the techniques of designing and manufacturing of the converter of next generation.

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Design and Implementation of eRTOS Real-time Operating Systems for Wearable Computers (웨어러블 컴퓨터를 위한 저전력 실시간 운영체제 eRTOS 설계 및 구현)

  • Cho, Moon-Haeng;Choi, Chan-Woo;Lee, Cheol-Hoon
    • The Journal of the Korea Contents Association
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    • v.8 no.9
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    • pp.42-54
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    • 2008
  • In recent years, embedded systems have been expanding their application domains from traditional embedded systems such as military weapons, robots, satellites and digital convergence systems such as celluar phones, PMP(Portable Multimedia Player), PDAs(Personal Digital Assistants) to Next Generation Personal Computers(NGPCs) such as eating PCs, wearable computers. The NGPCs are network-based, human-centric digital information devices diverged from the traditional PCs used mainly for document writing, internet searching and database management. Wearable computers with battery capacity and memory size limitations have to use real-time operating systems with small footprints and low power management techniques to provide user's QoS in spite of hardware constraints. In this paper, we have designed and implemented a low-power RTOS (called eRTOS) for wearable computers. The implemented eRTOS has 18KB footprints and the dynamic power management and the device power management schemes are adapted in it. Experimental results with wearable computer applications show that the low power techniques could save energy up to 47 %.

Implementation and Performance Analysis of PC Clusters using Fast PCs& High Speed Network (초고속 네트워크를 이용한 PC 클러스터의 구현과 성능 평가)

  • Kim, Young-Tae;Lee, Yonh-Hee;Choi, Jun-Tae;Oh, Jai-Ho
    • Journal of KIISE:Computer Systems and Theory
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    • v.29 no.2
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    • pp.57-64
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    • 2002
  • We implemented two fast PC clusters using fast PCs and high speed network. First. we built the first generation of 16 PC cluster and have used it for real-time operation at Cheju Regional Meteorological Office. Next, we built the second generation of 16PC with dual CUs cluster which was efficiently improved based on performance analysis of the first generation of cluster. In this research we also analyzed performance of two different clusters, which have different CPUs and communication devices using the parallel model MM5 which has been used for the real-time weather forecasting.

Transmission Time Analysis of WAP Packet Considering RLP Layer in CDMA Wireless Channel (CDMA 무선채널에서 RLP 계층을 고려한 WAP 패킷의 전송시간 분석)

  • 문일영;노재성;조성준
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.57-60
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    • 2001
  • This paper has studied the WAP packet transmission time, using WTP SAR algorithm. One method that is improved transfer ability, SAR fragmented WTP total message down from upper layer and then packet is transmitted to RLP frame time slot. In this paper, we analysis the transmission time of WAP packet with variable HLP layer size on the CDMA wireless channel for next generation systems as well as PCS, DCS. From the results, we can obtain the WAP packet transmission time and optimal WTP packet size.

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A Study on a Performance Analysis of Direct-Conversion Receiver In Additive White Gaussian Noise Channel (AWGN 채널환경에서 Direct-Conversion 수신기의 성능분석에 관한 연구)

  • 조형래;김철성;박성진
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.4
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    • pp.668-675
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    • 2001
  • Recently, the performance of the commercial PCS(Personal Communication Service) system has been improved to the uppermost limit and ultimately the next generation mobile communication is to be realized by IMT-2000 (International Mobile Communication-2000) to provide multimedia services. Therefore, the new type receiving system is researched actively and one of the most important part in a receiver is direct conversion method. The direct conversion method is suitable for low power consumption, small size, MMIC, and low price, which is to be adopted to the next generation mobile communication systems. In this case, however, several problems occur due to DC-offset. The DC-offset suppresses amplification of the required signal because of the leakage signal of frequency synthesizer in the system. In this thesis, the removing method of DC-offset was considered. There are four removing techniques of DC-offset, which are AC-coupling, large capacitor, DC-feedback loop, and DC-free coding. Among these, the AC-coupling method is the most simplest method and the DC-feedback loop method has the best performance. Then, the performance of the AC-coupling method and DC-feedback loop method are evaluated by HP's ADS simulation tool. As a result, the AC-coupling method cannot be used to the digital communication systems due to data loss. On the other hand, it was confirmed that the DC-feedback loop method is suitable for the direct conversion receiver.

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A Bi-objective Game-based Task Scheduling Method in Cloud Computing Environment

  • Guo, Wanwan;Zhao, Mengkai;Cui, Zhihua;Xie, Liping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.11
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    • pp.3565-3583
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    • 2022
  • The task scheduling problem has received a lot of attention in recent years as a crucial area for research in the cloud environment. However, due to the difference in objectives considered by service providers and users, it has become a major challenge to resolve the conflicting interests of service providers and users while both can still take into account their respective objectives. Therefore, the task scheduling problem as a bi-objective game problem is formulated first, and then a task scheduling model based on the bi-objective game (TSBOG) is constructed. In this model, energy consumption and resource utilization, which are of concern to the service provider, and cost and task completion rate, which are of concern to the user, are calculated simultaneously. Furthermore, a many-objective evolutionary algorithm based on a partitioned collaborative selection strategy (MaOEA-PCS) has been developed to solve the TSBOG. The MaOEA-PCS can find a balance between population convergence and diversity by partitioning the objective space and selecting the best converging individuals from each region into the next generation. To balance the players' multiple objectives, a crossover and mutation operator based on dynamic games is proposed and applied to MaPEA-PCS as a player's strategy update mechanism. Finally, through a series of experiments, not only the effectiveness of the model compared to a normal many-objective model is demonstrated, but also the performance of MaOEA-PCS and the validity of DGame.

Behavior Engine for WebGL-based Interactive Contents (WebGL 기반의 상호작용 콘텐츠를 위한 행위 엔진)

  • Seo, Jin-Seok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.862-865
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    • 2011
  • WebGL is a cross-platform web standard for a low-level 3D graphics API based on OpenGL ES 2.0 and presents 3D graphics in web browsers without installing extra plug-ins. The reason that WebGL is notable is because it is included in the HTML5 standard which is getting the spotlight as a next-generation RIA(Rich Internet Application) platform for variable devices such as PCs, smart phones, table PCs, and smart TVs. In this research, we would like to introduce and develop a behavior engine for easy and rapid authoring of complicated interactions and 3D object's behavior models in WebGL-based contents.

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Design of Power Divider for IMT-Advances System using GaAs Process (GaAs 공정을 이용한 IMT-Advances System용 전력분배기 설계)

  • Kim, Chang-Gi;Kim, Nam-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.184-184
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    • 2008
  • In this paper, a power divider with a multi-band and broadband are designed and fabricated using an InGaP/GaAs process. The design of this divider is based on multi-band because it is important in the next generation IMT-Advances system. In this design, power divider is fabricated with the frequency of 824 MHz to 894 MHz, 1.8 GHz to 2.2 GHz and 2.3 GHz to 2.4 GH for cellular, personal communication system (PCS) and Wireless Broadband Internet (WiBro). The topology of the designed power divider is based on the multi-section and fabricated using integrated passive device (IPD) library of nanoENS Inc. It is measured using network analyzer.

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Study on the Elimination of Residual Voltage in Quarter Wave Short Stub Surge Arrestor (4분의 1 파장 단락 스터브 방식 서지 어레스터의 잔여 전압 제거에 관한 연구)

  • Kim, Yeon-Tae;Won, Tae-Yeong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.8
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    • pp.33-44
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    • 2000
  • The lightning with high voltage and current can enter the basestations for mobile communication through their antenna. The device which can protect the basestation against the lightning, is surge arrestor. In this paper, the concept, kind, operating mechanism, design and fabrication of surge arrestor were studied. Based on the studied data, variable surge arrestors were designed for the current mobile communication service like a cellular, GSM and PCS and the next generation mobile communication like a IMT-2000. Computer simulation for the prediction of their characteristics and inner structure optimization for the improvement of their electrical characteristics were carried with high frequency 3D structure simulator. Quarter wave short stub surge arrestors for IMT-2000 were fabricated with their final design and then the measurement of electrical characteristics and the lightning test were executed. As a results of measurement, we obtained below 1.05 of VSWR, -0.035 dB of insertion loss, -150 dBc of intermodulation and 7∼ll V of residual voltage.

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Improvement of Smart Library Information Service System for SaaS-based Cloud Computing Service

  • Min, Byung-Won
    • International Journal of Contents
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    • v.12 no.4
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    • pp.23-30
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    • 2016
  • For a library to be able provide information services and fulfill its function as a knowledge convergence center capable of responding to various information demands, the development of next-generation information systems based on the latest information and communication technology is needed. The development of mobile information services using portable devices such smart phones and tablet PCs and information systems which incorporate the concepts of cloud computing, SaaS (Software as a Service), annotation and Library2.0 is also required. This paper describes a library information system that utilizes collective intelligence and cloud computing. The information system developed for this study adopts the SaaS-based cloud computing service concept to cope with the shift in the mobile service paradigm in libraries and the explosion of electronic data. The strengths of such a conceptual model include the sharing of resources, support of multi-tenants, and the configuration and support of metadata. The user services are provided in the form of software on-demand. To test the performance of the developed system, the efficiency analysis and TTA certification test were conducted. The results of performance tests, It is encouraging that, at least up to 100MB, the job time is approximately linear and with only a moderate overhead of less than one second. The system also passed the level-3 or higher criteria in the certification test, which includes the SaaS maturity, performance and application program functions.