• 제목/요약/키워드: Converged

검색결과 1,045건 처리시간 0.028초

A Research on the Proposal of U-Pavilion Adopted in Korean Residential Development

  • Yun, YongGib
    • Architectural research
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    • 제15권1호
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    • pp.1-8
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    • 2013
  • Over the past two decades following the 1990s, South Korea's IT industry has developed rapidly. In keeping with this trend, the architectural and urban planning sectors have also converged with IT and achieved advancement in new directions. This evolution includes a variety of conceptual terminologies such as 'home automation', ''home network', 'smart home, and 'ubiquitous-city'. However, smart homes and U-cities simply represent a conceptual extension of home networks, and there is little real difference in the technologies involved. In particular, U-cities remain focused on infrastructure rather than on the development of specific content; consequently, they have failed to demonstrate distinctive features to clearly differentiate themselves from conventional cities. In such a context, this research aims at the proposal of a 'ubiquitous pavilion' as a component of the efforts to develop a range of architectural contents that utilize ubiquitous technologies. By grafting the pavilion, one of the most basic forms in architecture, with cutting-edge ubiquitous technologies, this paper intends to suggest a multi-purpose architectural space readily and simply available not only in newly emerging U-cities, but to conventional cities as well.

다채널 위성인터넷방송서비스의 비즈니스모델에 관한 연구 -네트워크외부성 유.무에 따른 비교분석을 중심으로- (A New Business Model of the Multi-channel Satellite Webcasting Service)

  • 연규동
    • 기술혁신학회지
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    • 제4권3호
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    • pp.342-354
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    • 2001
  • The appearance of on-demand business model of multimedia contents is one of the biggest changes in the broadband Internet which aims at the high-speed Internet users. Currently the interest in the webcasting service, a new converged service of the broadcasting and the telecommunications, has been increased. However the quality of service is not guaranteed due to the bottleneck problem in a middle-mile as the fundamental limit of the Internet, and has not been improved greatly due to the small-scaled operators of the webcasting services. This study suggests a new business model of the multi-channel satellite webcasting service based on the satellite multicasting and content delivery network, which guarantees the quality of service and channelizes the contents by the type or by the special purpose.

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$MAP1, MAP2/G/1 FINITE QUEUES WITH SERVICE SCHEDULING FUNCTION DEPENDENT UPON QUEUE LENGTHS

  • Choi, Doo-Il;Lee, Sang-Min
    • 대한수학회보
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    • 제46권4호
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    • pp.673-689
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    • 2009
  • We analyze $MAP_1,\;MAP_2$/G/1 finite queues with service scheduling function dependent upon queue lengths. The customers are classified into two types. The arrivals of customers are assumed to be the Markovian Arrival Processes (MAPs). The service order of customers in each buffer is determined by a service scheduling function dependent upon queue lengths. Methods of embedded Markov chain and supplementary variable give us information for queue length of two buffers. Finally, the performance measures such as loss probability and mean waiting time are derived. Some numerical examples also are given with applications in telecommunication networks.

Simulation Testing in Mobile Networks Protocols and Applications Perspective

  • Jain Anurag;Tyagi Saurabh
    • 정보통신설비학회논문지
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    • 제3권1호
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    • pp.75-87
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    • 2004
  • The mobile industry is waking up to the reality that customers buy 'services', not technology. Thekey is to deliver a variety of differentiated services today and improve them as the advanced technology becomes available. In the increasingly data centric world of the future, the emphasis will be on the provision of a range of services audio, video, data and multimedia and of course speech. As we move closer to the realization of these mobile services in the conglomeration of converged networks, new challenges are being faced by the technology and application developers as well as the service providers to design, test and integrate new products and services. Functionalities like availability, scalability, performance and compatibility have become more important. This paper discusses the new test paradigms in the mobile networks, both from the applications and the protocols perspective.

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프로펠러 특성의 이론적 산정법에 관한 연구 (A Study on the Theoretical Calculation of Screw Propeller Open-Water Characteristics)

  • 송강섭
    • 한국항해학회지
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    • 제14권3호
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    • pp.15-33
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    • 1990
  • In recent years, propellers with various blade configurations such as highly skewed propellers are often fitted to ships from the viewpoint of reduction of vibration and noise. In the design of such propellers, design charts based on methodical series tests are to be complemented by theoretical calculations for accurate estimation of propeller open-water characteristics. The author intended to develop a method to estimate propeller open-water characteristics based on Quasi -Vortex - Lattice Method originally developed by Lan for solving planar thin wings, The Quasi - Vortex - Lattice Method has the simplicity and flexibility of Vortex - Lattice Method. Its accuracy is comparable to that of the Vortex - Lattice Method. Converged solution can be obtained with a small number of control points and further, leading edge suction force can be calculated directly. In the present paper, a numerical method to estimate propeller open-water characteristics based on the Quasi - Vortex - Lattice Method is reviewed and its application to marine propellers is described in detail. Comparison of propeller open-water characteristics obtained by the present method with experimental data showed good agreement for a wide variety of propellers including highly skewed propellers.

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Back-Propagation방법의 수렴속도 및 학습정확도의 개선 (Acceleration the Convergence and Improving the Learning Accuracy of the Back-Propagation Method)

  • 이윤섭;우광방
    • 대한전기학회논문지
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    • 제39권8호
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    • pp.856-867
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    • 1990
  • In this paper, the convergence and the learning accuracy of the back-propagation (BP) method in neural network are investigated by 1) analyzing the reason for decelerating the convergence of BP method and examining the rapid deceleration of the convergence when the learning is executed on the part of sigmoid activation function with the very small first derivative and 2) proposing the modified logistic activation function by defining, the convergence factor based on the analysis. Learning on the output patterns of binary as well as analog forms are tested by the proposed method. In binary output patter, the test results show that the convergence is accelerated and the learning accuracy is improved, and the weights and thresholds are converged so that the stability of neural network can be enhanced. In analog output patter, the results show that with extensive initial transient phenomena the learning error is decreased according to the convergence factor, subsequently the learning accuracy is enhanced.

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안정한 적응 IIR 필터를 사용한 능동머플러 구현 (Implementation of active mufflers using stabilized adaptive IIR filters)

  • 방경욱;서성대;남현도
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.3066-3068
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    • 2005
  • Noise can make surrounding environments inferior and deteriorates operation efficiency, and it can bring aural damage as well as give a person psychological stress. Therefore, necessity of study about noise control is increased for better labor conditions and agreeable habitat. In this paper, implementation of active mufflers using a stable IIR adaptive filters is presented. The IIR filter structure is more effective when acoustic feedback exists, but the adaptive IIR filters could be unstable when the filter algorithm is not yet converged. A stabilizing process for adaptive IIR filter is introduced in this paper. Experiments using a TMS320C32 digital signal processor have performed to show the effectiveness of a proposed algorithm.

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자동차용 에어컨 시스템의 성능해석에 관한 연구 (A Study on the Performance Analysis of Automotive Air Conditioning System)

  • 이대웅;유성연
    • 설비공학논문집
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    • 제14권4호
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    • pp.304-314
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    • 2002
  • Performance analysis of the automotive air-conditioning system is conducted by using computer simulation, and performance tests are carried out by using the climate wind tunnel in order to verify simulation. Evaporator and condenser were modeled by using empirical correlation which was obtained from calorimeter data, and compressor was modeled by using map based method. The steady state thermodynamic conditions of refrigerant satisfying mass and energy balance were assumed in the simulation program for automotive airconditioning system. The system performance was analyzed by finite difference method until differential air enthalpy between evaporator inlet and outlet becomes converged. Simulation results are in good agreement with experimental results at most operating conditions. Variation of discharge temperature and pressure of compressor, outlet temperature of evaporator, cooling capacity, and COP were investigated in term of air volume flow rate for evaporator, compressor capacity, compressor speed, superheat of thermostatic expansion valve, and diameter of suction line.

Parameter Recovery for LIDAR Data Calibration Using Natural Surfaces

  • Lee Impyeong;Moon Jiyoung;Kim Kyoung-ok
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.642-645
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    • 2004
  • This paper focuses on recovering systematic biases during LIDAR calibration, particularly using natural surfaces as control features. Many previous approaches have utilized all the points overlapping with the control features and often experienced with an inaccurate value converged with a poor rate due to wrong correspondence in pairing a point and the corresponding control features. To overcome these shortcomings, we establish a preventive scheme to select the pairs of high confidence, where the confidence value is based on the error budget associated with the point measurement and the linearity and roughness of the control feature. This approach was then applied to calibraring the LIDAR data simulated with the given systematic biases. The parameters were successfully recovered using the proposed approach with the accuracy and convergence rate superior to those using the previous approaches.

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변동하중 조건에서 점접촉 탄성유체윤활의 유막거동 연구 (Study of the Film Thickness Behaviors in the Elastohydrodynamic Lubrication of Circular Contact under the Dynamic Loading Condition with Multigrid Multilevel Method)

  • 조재철;장시열
    • Tribology and Lubricants
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    • 제25권6호
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    • pp.367-373
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    • 2009
  • Many research of elastohydrodynamic lubrication (EHL) has been performed under the condition of steady state loading. However, mechanical elements undergo severe high loads that are in the fluctuating modes of frequency and amplitude. Conventional numerical method for the circular contact of EHL study has the difficulty in making the film thickness and pressure of EHL converged in high loads of steady state as well as fluctuating loading conditions. In this work, multigrid multilevel method are used for the stable convergence of film pressure and thickness under the conditions of high as well as varying loads, and very stable solutions of film behaviors with elastic deformation are obtained. Several results of dynamic loading condition are shown and compared with those of steady state condition in the aspects of circular EHL film thickness and pressure.