• Title/Summary/Keyword: Cellular system

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Erlang Capacity and Call Blocking Probability of CDMA Hierarchical Cellular Systems with Soft Handoff (소프트 핸드오프를 갖는 CDMA 계층구조 셀룰러 시스템의 Erlang 용량과 호 차단확률)

  • Seong, Bong-Hun;O, Hyeon-Seok;Han, Jae-Chung
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.8
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    • pp.481-490
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    • 2000
  • This paper analyzes interference power, Erlang capacity, the number of handoff occurrences, and call blocking probability with respect to the cell radius, the soft handoff region, and the mobile's velocity in a CDMA hierarchical cellular system. The microcell cellular system has the higher Erlang capacity than the macrocell cellular system. However, the microcell cellular system, which has a high system capacity through frequency reuse has the call blocking probability higher than macrocell cellular system. Also the interference power and the call blocking probability are decreased with the operation of soft handoff. Therefore, this paper presents the optimization of soft handoff region so as to maximize system's Erlang capacity with the low the call blocking probability according to mobile's velocity in the CDMA hierarchial cellular system.

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An integrated framwork for a cellular manufacturing system (셀 생산 시스템의 통합 구조)

  • 이노성;임춘우
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.89-92
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    • 1997
  • The objective of this paper is to provide an alternative framework for the integration of process planning and scheduling in cellular manufacturing. The concept of an integrated cellular manufacturing system is defined and the system architecture is presented. In an integrated cellular manufacturing system, there are three modules : the process planning module, the manufacturing-cell design module, and the cell-scheduling module. For each module, the tasks and their activities are explained.

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An Intergrated Framework for a Cellular Manufacturing System (셀 생산 시스템의 통합 구조)

  • 임춘우;이노성
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.43
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    • pp.219-228
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    • 1997
  • The objective of this paper is to provide an alternative framework for the integration of process planning and scheduling in cellular manufacturing. The concept of an integrated cellular manufacturing system is defined and the system architecture is presented. In an integrated cellular manufacturing system, there are three modules : the process planning module, the manufacturing-cell design module, and the cell-scheduling module. For each module, the tasks and their activities are explained.

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Energy D2D Tx-Rx assignment in the Cellular System

  • Oh, Changyoon
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.8
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    • pp.41-46
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    • 2017
  • In this paper, we investigate the D2D Transmitter(Tx) and Receiver(Rx) pair assignment problem in the cellular system where D2D users share the uplink resource of the cellular system. Sharing the uplink resource of the cellular system may cause interference to the cellular system, though it is beneficial to improve the D2D user Capacity. Therefore, to protect the cellular users, D2D transmit power should be carefully controlled. In this work, we focus on optimal Tx-Rx assignment in such a way that the total transmit power of users is minimized. First, we consider the optimum Tx-Rx assignment in general and the corresponding complexity. Then, we propose an iterative D2D Tx-Rx assignment algorithm with low complexity that can minimize total transmit power of users. Finally, we present the numerical examples that show the complexity and the convergence to the unique transmit power level.

A Study on Implementation of Evolving Cellular Automata Neural System (진화하는 셀룰라 오토마타 신경망의 하드웨어 구현에 관한 연구)

  • 반창봉;곽상영;이동욱;심귀보
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.255-258
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    • 2001
  • This paper is implementation of cellular automata neural network system which is a living creatures' brain using evolving hardware concept. Cellular automata neural network system is based on the development and the evolution, in other words, it is modeled on the ontogeny and phylogeny of natural living things. The proposed system developes each cell's state in neural network by CA. And it regards code of CA rule as individual of genetic algorithm, and evolved by genetic algorithm. In this paper we implement this system using evolving hardware concept Evolving hardware is reconfigurable hardware whose configuration is under the control of an evolutionary algorithm. We design genetic algorithm process for evolutionary algorithm and cells in cellular automata neural network for the construction of reconfigurable system. The effectiveness of the proposed system is verified by applying it to time-series prediction.

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A Study on Effective Cell Model for CDMA Cellular System Simulation (CDMA 셀룰라 시스템 시뮬레이션을 위한 효과적인 셀 모델에 관한 연구)

  • 윤상흠;권용석
    • Journal of Information Technology Applications and Management
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    • v.10 no.4
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    • pp.149-157
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    • 2003
  • In this paper, we propose a ceil model based on the wraparound method to simulate the hierarchical CDMA cellular system in an effective and efficient manner. The model uses the minimal number of cells by considering only one tier but compensates the interference by other cells in the higher tiers sufficiently. Various numerical tests demonstrate that the proposed model can be used to simulate the complex and large-sized hierarchical cellular system effectively. Especially, the interference compensation can reduce the required simulation time to 1/100 for 10 tiers cellular system.

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A Study on Cellular Communication with Frequency Hopping Technique (주파수 도약 기술을 이용한 셀루라 통신에 관한 연구)

  • 진봉철;박상규;한영열
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.6
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    • pp.517-532
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    • 1991
  • This paper shows performance analysis for FH/MF나 systems over the cellular mobile communication channel. The Channel capacity over FH/MF나 system is represented as a function of deletion probalblity (Po) and insertion probalbility(Pt). The spectral efficiency of the system serves as a per formance of cellular system is inferior to that of non cellular system. In the case of frequency reuse, we get the best performance when the reuse pattern(N) is 3.

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Interference Mitigation Scheme for Device-to-Device MIMO Communications Underlaying a Cellular Network

  • Nam, Yujin;So, Jaewoo;Kim, Jinsung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.4
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    • pp.1841-1865
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    • 2017
  • This paper proposes a new interference mitigation scheme for device-to-device (D2D) communications underlaying a cellular network. The object of the proposed scheme is to determine the number of data streams, a precoding matrix, and a decoding matrix of D2D networks so as to maximize the system capacity given the number of data streams of a cellular network while satisfying the constraint of the inter-system interference from D2D networks to the cellular network. Unlike existing interference mitigation schemes based on the interference alignment technique, the proposed scheme operates properly regardless of the number of data streams of a cellular network and moreover it does not require changing the precoding and decoding matrices of a cellular network. The simulation results demonstrate that the proposed scheme significantly increases the system capacity by mitigating the intra- and inter-system interference.

Development of a Screening System for Drugs Against Human Papillomavirus-Associated Cervical Cancer: Based On E7-Rb Binding

  • Cho, Young-Sik;Cho, Cheong-Weon;Kang, Jeong-Woo;Cho, Min-Chul;Lee, Kyung-Ae;Shim, Jung-Hyun;Kwon, Our-Han;Choe, Yong-Kyung;Park, Sue-Nie;Yoon, Do-Young
    • BMB Reports
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    • v.34 no.1
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    • pp.80-84
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    • 2001
  • The human papillomavirus E7 protein can form a specific complex with a retinoblastoma tumor suppressor gene product (p105-Rb) that results in the release of the E2F transcription factor, which is critical for the growth-deregulation and transforming properties of the viral E7 oncoprotein. In an attempt to apply interaction between the E7 oncoprotein and a target cellular protein Rb for an in vitro screening system for drugs against human papillomavirus infection, we primarily investigated the E7Rb binding through a pull down assay and enzyme-linked immunosorbent assay. The pull down assay showed that both glutathione S-transferase-tagged E7 and His-tagged E7 immobilized on resins specifically produced complexes with bacterially expressed Rb in a dose-dependent manner, as determined by immunoblot analyses. This result coincided with that of an enzyme-linked immunosorbent assay, which is a useful system for the mass screening of potential drugs. Taken together, this screening system (based on the interaction between E7 and Rb) can be a promising system in the development of drugs against cervical cancers caused by human papillomavirus infection.

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The Design of an Intelligent Assembly Robot System for Lens Modules of Phone Camera.

  • Song, Jun-Yeob;Lee, Chang-Woo;Kim, Yeong-Gyoo
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.649-652
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    • 2005
  • The camera cellular phone has a large portion of cellular phone market in recent year. The variety of a customer demand makes a fast model change and the spatial resolution is changed from VGA to multi-mega pixel. The 1.3 mega pixel (MP) camera cellular phone was first released into the Korean market in October 2003. The major cellular phone companies released a 2MP camera cellular phone that supports zoom function and a 2MP camera cellular phone is settled down with the Korea cellular phone market. It makes a keen competition in price and demands automation for phone camera module. There is an increasing requirement for the automatic assembly to correspond to a fast model change. The hard automation techniques that rely on dedicated manufacturing system are too inflexible to meet this requirement. Therefore in this study, this system is designed with the flexibility concept in order to cope with phone camera module change. The system has a same platform that has X-Y-Z motion or X-Z motion with ${\mu}m$order accuracy. It has a special gripper according to the type of a component to be put together. If the camera model changes, the gripper may be updated to fit for the camera module. The controller of this system acquires the data sets that have the information about the assembly part by the tray. This information is obtained ahead of an inspection step. The controller excludes an inferior part to be assembled by using this information to diminish the inferior goods. The assembly jig used in this system has a function of self adjustment that reduces the tact time and also diminish the inferior goods. Finally, the intelligent assembly system for phone camera module will be designed to get a flexibility to meet model change and a high productivity with a high reliability.

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