• Title/Summary/Keyword: codes and standards

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Design and Implementation of OCQPSK/HPSK Modem using Digital Signal Processors for Software Defined Radio Applications

  • Cho, Pyung-Dong;Kang, Byeong-Gwon
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1428-1431
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    • 2002
  • It is general opinion that the future mobile multimedia networks will use different standards and a prospective solution to this problem will be software defined radio (SDR) techniques. SDR provides the flexibility to support multiple air interfaces and signal processing functions at the same time. Especially, digital signal processors and FPGAs are widely used for implementation of these adaptive and flexible functions of a baseband modem for SDR applications. Also, it is known that the modulation schemes of OCQPSK (Orthogonal Complex QPSK) and HPSK (Hybrid PSK) are used for IMT-2000 services of cdma2000 and WCDMA, respectively. Thus, in this paper, we design and implement an OCQPSK / HPSK modem using a DSP chip of Texas Instrument's TMS320C6701. One modulation scheme is operated by adaptive selection between the two schemes and 5 physical traffic channels differentiated by orthogonal codes are implemented in one DSP chip and each channel has 1Mbps data rates and 8Mcps chip rates.

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Free-range Poultry Production - A Review

  • Miao, Z.H.;Glatz, P.C.;Ru, Y.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.1
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    • pp.113-132
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    • 2005
  • With the demand for free-range products increasing and the pressure on the intensive poultry industry to improve poultry welfare especially in western countries, the number of free-range poultry farms has increased significantly. The USA, Australia and European countries have developed Codes of Practice for free-range poultry farming which detail the minimum standards of husbandry and welfare for birds. However, the performance and liveability of free-range birds needs to be improved and more knowledge is required on bird husbandry, feed supply, disease control and heat wave management. This review examines the husbandry, welfare, nutrition and disease issues associated with free-range poultry systems and discusses the potential of incorporating free-range poultry into a crop-pasture rotation system.

DIFFERENT APPROACHES TO WELDING TRAINING AND CERTIFICATION

  • Osama, Al-Erhayem
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.430-432
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    • 2002
  • Some confusion in the terminology concerning the weld quality and its assurance seems caused by the different practises currently in use around the world. Qualified welding personnel are not automatically certified personnel. Education and training are the tools to obtain qualification. Flexibility in training and education seems logical and the most cost-effective way to obtain qualified personnel. A third party seems essential for issuing recognised Certificates. Manufacturers of welded products continue to face increased demands and concerns regarding weld quality. The following are the main conditions influencing weld quality: $\bigcirc$ Establishing reliable productions procedures and tests that meet the requirements of established codes and standards. $\bigcirc$ Finding qualified welding personnel capable of reliably carrying out established welding procedures. The issue of hiring and keeping skilled welding personnel has been a crucial consideration for manufacturers worldwide for the past few decades. It will continue to be a concern for decades to come.

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A study on the development of British museum library and its cataloguing rules (대영박물관도서관의 발전과정과 그 목록규칙에 관한 고찰)

  • 배영활
    • Journal of Korean Library and Information Science Society
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    • v.16
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    • pp.69-98
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    • 1989
  • The purpose of this study is to review the historical development of British Museum Library and its cataloging rules which really marked the beginning of the modern era of cataloguing. The results of the study can be summarized as follows (1) Sir Anthony Panizzi was the most creative force in the history of the British Museum Library. He devoted himself to the formation of the British Museum Library cataloging policy and the compilation of printed catalogues. Moreover, he laid down the sound acquisitions policy and the vigorous a n.0, pplication of the copyright deposit privilege. He designed a great circular reading room and raised standards of library service and administration. (2) British Museum Library Cataloging Rules : 1. are notable for their pioneering efforts-this was the first major catalogue code-and for their influence on all subsequent codes. 2. introduced the concept of corporate authorship but has never dealt with problem very satisfactory. 3. went to great lengths to avoid title entry. 4. used a number of form heading, example for, ACADEMIES, PERIODICAL PUBLICATION, EPHEMERIDES, CATALOGUES etc.

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An Experimental Study on Allowable Size of Incomplete Penetration in Butt Joint Bridge Weld Considering Fatigue Strength (교량의 피로강도를 고려한 맞대기용접부 불안전용입 한계결함 결정에 관한 연구)

  • 백영남;장영권
    • Journal of Welding and Joining
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    • v.18 no.3
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    • pp.68-75
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    • 2000
  • The incomplete penetration(IP) discontinuity in butt joint weld, which is detected during safety analysis of the steel bridge by nondestructive evaluation(NDE) method, is classified as unacceptable defect according to the NDE codes and standards. In fact, there are a little allowance in butt joint weld in the view point of design criterion, and also detected IP discontinuity should be classified and evaluated for the fatigue strength and residual life estimation. In this study, we performed fatigue test to evaluate the fatigue strength of high strength steel(SWS490A) containing IP discontinuities in various size, the results compared and classified according to the bridge construction standard specification which published by korea administration of construction and traffic. Experimental results could be used to evaluate and estimate the IP discontinuities considering different stress range in butt joint bridge weld during periodic safety inspection.

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Optimum Life Cycle Cost Design of High-Speed Railway Steel Bridges (고속철도 강교량의 총기대비용 최적설계)

  • 조효남;민대홍;조준석
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.10a
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    • pp.109-114
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    • 2000
  • In this paper, an optimum design model for minimizing the life-cycle cost (LCC) of high-speed railway steel bridges is proposed The point is that it takes into account service life process as a whole, and thus the life-cycle costs include initial (design, testing, and construction) costs, maintenance costs, expected strength failure costs and expected serviceability failure costs. The problem is formulated as that of minimization of expected total life-cycle cost with respect to the design variables. By processing the optimum LCC design the effective and rational basis is proposed for calculating the total LCC and the sensitivity analysis of LCC is peformed. Based on a numerical example, it may be positively stated that the optimum LCC design of high-speed railway steel bridges proposed in this study provides a lot more rational and economical design, and thus the proposed approach will expedite the development of new concepts and design methodologies that may have important implications in the next generation performance-based design codes and standards.

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U.S. GENERATION IV REACTOR INTEGRATED MATERIALS TECHNOLOGY PROGRAM

  • Corwin William R.
    • Nuclear Engineering and Technology
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    • v.38 no.7
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    • pp.591-618
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    • 2006
  • An integrated R&D program is being conducted to study, qualify, and in some cases, develop materials with required properties for the reactor systems being developed as part the U.S. Department of Energy's Generation IV Reactor Program. The goal of the program is to ensure that the materials research and development (R&D) needed to support Gen IV applications will comprise a comprehensive and integrated effort to identify and provide the materials data and its interpretation needed for the design and construction of the selected advanced reactor concepts. The major materials issues for the five primary systems that have been considered within the U.S. Gen IV Reactor Program-very high temperature gas-cooled, supercritical water-cooled, gas-cooled fast spectrum, lead-cooled fast spectrum, and sodium-cooled fast spectrum reactors-are described along with the R&D that has been identified to address them.

Effect of temperature gradient on track-bridge interaction

  • Kumar, Rakesh;Upadhyay, Akhil
    • Interaction and multiscale mechanics
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    • v.5 no.1
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    • pp.1-12
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    • 2012
  • Considerable longitudinal rail forces and displacements may develop in continuous welded rail (CWR) track on long-span bridges due to temperature variations. The track stability may be disturbed due to excessive relative displacements between the sleepers and ballast bed and the accompanied reduction in frictional resistance. For high-speed tracks, however, solving these problems by installing rail expansion devices in the track is not an attractive solution as these devices may cause a local disturbance of the vertical track stiffness and track geometry which will require intensive maintenance. With reference to temperature, two actions are considered by the bridge loading standards, the uniform variation in the rail and deck temperature and the temperature gradient in deck. Generally, the effect of temperature gradient has been disregarded in the interaction analysis. This paper mainly deals with the effect of temperature gradient on the track-bridge interaction with respect to the support reaction, rail stresses and stability. The study presented in this paper was not mentioned in the related codes so far.

Optimum Life Cycle Cost Design of Steel Box Girder Bridges (강상형교의 최적 Life Cycle Cost 설계)

  • 조효남;민대홍;김구선
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.151-158
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    • 1998
  • This paper presents an optimal decision model for minimizing the life-cycle cost of steel box girder bridges. The point is that it takes into account service life process as a whole, and the life-cycle costs include initial (design, testing, and construction) costs, maintenance costs and expected failure costs. The problem is formulated as that of minimization of expected total life-cycle cost with respect to the design variables. The optimal solution identifies those values of the decision variables that result in minimum expected total cost. The performance constraints in the form of flexural failure and shear failure are those specified in the design code. Based on extensive numerical investigations, it may be positively stated that the optimum design of steel box girder bridges based on life-cycle cost approach proposed in this study provides a lot more rational and economical design, and thus the proposed approach will propose the development of new concepts and design methodologies that may have important implications in the next generation performance-based design codes and standards.

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The Combined Testing System for Simulating Condition of Acceleratedly Deteriorated Environment (전력기기 내환경특성평가를 위한 복합가속열화시스템 제작)

  • Lee, J.G.;Kim, M.K.;Kim, I.S.;Jeong, J.Y.
    • Proceedings of the KIEE Conference
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    • 2006.10a
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    • pp.182-183
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    • 2006
  • It has been studied about the important consideration in designing and construction of the reliability assessment facilities including the combined testing system for simulating condition of acceleratedly deteriorated environment, which enable to test and evaluate the large-sized HV power apparatus without any disassembly up to transmission class in this paper. Also it is described simply about its ratings and main technical specifications and trial running of the system. To evaluate the performance characteristics against combined test condition for various power installation, especially for the polymer type insulators and kinds of bushings, brief investigation and an analysis of test objects and related international codes and standards have been conducted.

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