• Title/Summary/Keyword: multiple use

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Orthogonal Multi-beam Techniques for Multi-user Diversity and Multiplexing Gain in Packet-based Wireless Systems (패킷 기반 무선 시스템에서 다중 사용자 이득과 다중화 이득 획득을 위한 다중 직교빔 전송 기법)

  • Oh, Dong-Chan;Lee, Yong-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.3A
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    • pp.286-295
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    • 2008
  • In this paper, we consider the use of orthogonal multiple beams (OMBs) to simultaneously achieve multi-user diversity and multiplexing gain in a packet-based wireless system. Previous OMB scheme considers the use of a fixed number of multiple beams equal to the number of transmit antennas. However, unless the number of active users is sufficiently large, the use of a fixed number of multiple beams may not provide desired performance due to the interference signal transmitted through other beams, being even worse than the use of a single beam. To alleviate this problem, we consider the adjustment of the number of beams in use to maximize the spectral efficiency according to the operating condition. Simulation results show the validity of the proposed scheme.

Correlation Analysis of Reservoir Water Quality with respect to Land Use Types of Watersheds (유역 토지이용과 저수지 수질의 상관관계 분석)

  • Youn, Dong-Koun;Chung, Sang-Ok
    • Current Research on Agriculture and Life Sciences
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    • v.24
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    • pp.49-53
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    • 2006
  • The objective of this study was to present regression equations between reservoir water quality and land use types of the watersheds. In order to derive regression equations, a multiple linear regression analysis was used using observed data from 88 reservoirs in the Kyungpook Provcince. The measured values of BOD, COD, T-N, and T-P were correlated with the areas of land use types. 23 regression equations were obtained for all the water quality items and watershed sizes. The results showed that 2 regression equations have the multiple correlation coefficient(MCC) above 0.90, 10 regression equations have the MCC values from 0.70 to 0.90, 9 equations have the MCC from 0.40 to 0.70, and 2 equations have the MCC from 0.20 to 0.40. The results of this study can be used to estimate reservoir water quality simply and quickly in the planning phase.

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Effect of Mating Duration and Multiple Use of Male Moth on Reproductive Performance of Some Cross Breeds of Silkworm, Bombyx mori L.

  • Sarkar, Kunal;Mandal, Manmatha;Moorthy, Shanmugam Manthira
    • International Journal of Industrial Entomology and Biomaterials
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    • v.19 no.2
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    • pp.215-219
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    • 2009
  • The effect of mating duration and multiple use of male on fecundity and fertility was investigated in the hybrids of Silkworm, Bombyx mori L. One hour to five hours of mating duration did not affect egg laying (fecundity) significantly, while fertilization affected significantly. Below 50% fertility was noticed when mating duration was reduced to below two hours. Similarly multiple use of male caused significant reduction in fertility but not fecundity. Till fourth mating no significant reduction in fertility was observed, thereafter fertility reduced considerably.

A Study on Efficient Use of Dual Data Memory Banks in Flight Control Computers

  • Cho, Doosan
    • International Journal of Internet, Broadcasting and Communication
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    • v.9 no.1
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    • pp.29-34
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    • 2017
  • Over the past several decades, embedded system and flight control computer technologies have been evolved to meet the diverse needs of the mobile device market. Current embedded systems are at the heart of technologies that can take advantage of small-sized specialized hardware while still providing high-efficiency performance at low cost. One of these key technologies is multiple memory banks. For example, a dual memory bank can provide two times more memory bandwidth in the same memory space. This benefit take lower cost to provide the same bandwidth. However, there is still few software technologies to support the efficient use of multiple memory banks. In this study, we present a technique to efficiently exploit multiple memory banks by software support. Specifically, our technique use an interference graph to optimally allocate data to different memory banks by an optimizing compiler. As a result, the execution time can be improved upto 7% with the proposed technique.

Efficient Use of On-chip Memory through Profile-Driven Array Reorganization

  • Cho, Doosan;Youn, Jonghee
    • IEMEK Journal of Embedded Systems and Applications
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    • v.6 no.6
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    • pp.345-359
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    • 2011
  • In high performance embedded systems, the use of multiple on-chip memories is an essential architectural feature for exploiting inherent parallelism in multimedia applications. This feature allows multiple data accesses to be executed in parallel. However, it remains difficult to effectively exploit of multiple on-chip memories. The successful use of this architecture strongly depends on how to efficiently detect and exploit memory parallelism in target applications. In this paper, we propose a technique based on a linear array access descriptor [1], which is generated from profiled data, to detect and exploit memory parallelism. The proposed technique tackles an array reorganization problem to maximize memory parallelism in multimedia applications. We present preliminary experiments applying the proposed technique onto a representative coarse grained reconfigurable array processor (CGRA) with multimedia kernel codes. Our experimental results demonstrate that our technique optimizes data placement by putting independent data on separate storage. The results exhibit 9.8% higher performance on average compared to the existing method.

Analysis of Multiple Network Accessibilities and Commercial Space Use in Metro Station Areas: An Empirical Case Study of Shanghai, China

  • Zhang, Lingzhu;Zhuang, Yu
    • International Journal of High-Rise Buildings
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    • v.8 no.1
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    • pp.49-56
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    • 2019
  • Against the background of the rapid development of the Shanghai Metro network, this paper attempts to establish an analytical approach to evaluate the impact of multiple transport network accessibilities on commercial space use in metro station areas. Ten well-developed metro station areas in central Shanghai are selected as samples. Commercial space floor area and visitors in these areas are collected. Using ArcGIS and Spatial Design Network Analysis, the Shanghai Metro network and road network are modeled to compute diversified transport accessibilities. Evidence from land use and commercial space floor area within a 0-to-500-meter buffer zone of stations is consistent with location and land-use theory: commercial land use is concentrated closer to stations. Correlation analysis suggests that hourly visitors to the shopping mall are mainly influenced by metro network accessibility, while retail stores and restaurants are affected by both metro and pedestrian accessibility.

Procedures for Detecting Multiple Outliers in Linear Regression Using R

  • Kwon, Soon-Sun;Lee, Gwi-Hyun;Park, Sung-Hyun
    • Proceedings of the Korean Statistical Society Conference
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    • 2005.11a
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    • pp.13-17
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    • 2005
  • In recent years, many people use R as a statistics system. R is frequently updated by many R project teams. We are interested in the method of multiple outlier detection and know that R is not supplied the method of multiple outlier detection. In this talk, we review these procedures for detecting multiple outliers and provide more efficient procedures combined with direct methods and indirect methods using R.

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A theoretical model of multiple team membership's effects on productivity and learning of Enterprises (다중팀 멤버십이 기업 생산성과 학습에 미치는 영향)

  • Lee, Won-Haeng
    • Journal of Industrial Convergence
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    • v.13 no.1
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    • pp.11-23
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    • 2015
  • Organizations use multiple team membership to enhance individual and team productivity and learning, but this structure creates competing pressures on attention and information, which make in difficult to increase both productivity and learning. My model describes how the number and variety of multiple team memberships drive different mechanisms, yielding distinct effects.

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Computational Methods for Detection of Multiple Outliers in Nonlinear Regression

  • Myung-Wook Kahng
    • Communications for Statistical Applications and Methods
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    • v.3 no.2
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    • pp.1-11
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    • 1996
  • The detection of multiple outliers in nonlinear regression models can be computationally not feasible. As a compromise approach, we consider the use of simulated annealing algorithm, an approximate approach to combinatorial optimization. We show that this method ensures convergence and works well in locating multiple outliers while reducing computational time.

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Logic synthesis algorithm of multiple-output functions using the functional decomposition method for the TLU-type FPGA (기능적 분해방법을 이용한 TLU형 FPGA의 다출력 함수 로직 합성 알고리즘 설계)

  • 손승원;장종수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.11
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    • pp.2365-2374
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    • 1997
  • This paper describes two algorithms for technology mapping of multiple output functions into interesting and pupular FPGAs(Field Programmable Gate Array) that use look-yp table memories. For improvement of technology mapping for FPGA, we use the functional decompoition method for multiple output functions. Two algorithms are proposed. The one is the Roth-Karpalgorithm extended for multiple output functions. The other is the efficient algorithm which looks for common decomposition functions through the decomposition procedure. The cost function is used to minimize the number of CLBs and nets and to improve performance of the network. Finally we compare our new algorithm with previous logic design technique. Experimental resutls show sigificant reduction in the number of CLBs and nets.

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