• Title/Summary/Keyword: Technological performance

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Lightweight Cryptography and RFID: Tackling the Hidden Overhead

  • Poschmann, Axel;Robshaw, Matthew J.B.;Vater, Frank;Paar, Christof
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.2
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    • pp.98-116
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    • 2010
  • The field of lightweight cryptography has developed significantly over recent years and many impressive implementation results have been published. However these results are often concerned with a core computation and when it comes to a real implementation there can be significant hidden overheads. In this paper we consider the case of cryptoGPS and we outline a full implementation that has been fabricated in ASIC. Interestingly, the implementation requirements still remain within the typically-cited limits for on-the-tag cryptography.

PRESENT AND FUTURE OF SUPER HIGH-EFFICIENCY TANDEM SOLAR CELLS

  • Yamaguchi, Masafumi
    • Electrical & Electronic Materials
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    • v.11 no.11
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    • pp.37-45
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    • 1998
  • In this paper, present status of super high-efficiency tandem solar cells has been reviewed and key issues for realizing super high-efficiency have also been discussed. In addition, the terretrial R&D activities of tandem cells, in the New Sunshine Program of MITI(Ministry of International Trade and Industry) and NEDO(New Energy and Industrial Technology Development Organization) in Japan are reviewed briefly. The mechanical stacked 3-junction cells of monolithically grown InGaP/GaAs 2-junction cells and InGaAs cells have reached the highest efficiency achieved in Japan of 33.3% at 1-sun AM1.5. This paper also reports high-efficiency InGaP/GaAs 2-junction solar cells with a world-record efficiency of 26.9% at AM0, 28$^{\circ}C$ and radiation damage recovery phenomena of the tandem cell performance due to minority-carrier injection under light illumination or forward bias, which causes defect annealing in InGaP top cells. Future prospects for realizing super-high efficiency and low-cost tandem solar cells are also described.

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Improved phenomenological modelling of transient thermal strains for concrete at high temperatures

  • Nielsen, Claus V.;Pearce, Chris J.;Bicanic, Nenad
    • Computers and Concrete
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    • v.1 no.2
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    • pp.189-209
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    • 2004
  • Several extensions to the Thelandersson phenomenological model for concrete under transient high temperatures are explored. These include novel expressions for the temperature degradation of the elastic modulus and the temperature dependency of the coefficient of the free thermal strain. Furthermore, a coefficient of thermo mechanical strain is proposed as a bi-linear function of temperature. Good qualitative agreement with various test results taken from the literature is demonstrated. Further extensions include the effects of plastic straining and temperature dependent Poisson's ratio. The models performance is illustrated on several simple benchmark problems under uniaxial and biaxial stress states.

Applicability of HRA to Support Advanced MMI Design Review

  • Kim, Inn-Seock
    • Nuclear Engineering and Technology
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    • v.32 no.1
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    • pp.88-98
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    • 2000
  • More than half of all incidents in large complex technological systems, particularly in nuclear power or aviation industries, were attributable in some way to human erroneous actions. These incidents were largely due to the human engineering deficiencies of man-machine interface (MMI). In nuclear industry, advanced computer-based MMI designs are emerging as part of new reactor designs. The impact of advanced MMI technology on the operator performance, and as a result, on plant safety should be thoroughly evaluated before such technology is actually adopted in nuclear power plants. This paper discusses the applicability of human reliability analysis (HRA) to support the design review process. Both the first-generation and the second-generation HRA methods are considered focusing on a couple of promising HRA methods, i.e., ATHEANA and CREAM, with the potential to assist the design review process.

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Study on Design of the Cooling System Used for the Propulsion System of the High-Speed EMU (동력분산형 고속전철의 추진시스템용 냉각장치의 설계 연구)

  • Ryoo, Seong-Ryoul;Kim, Sung-Dae;Ki, Jae-Hyung;Yim, Kwang-Bin;Kim, Chul-Ju
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1221-1226
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    • 2008
  • Present, the cooling method of using a phase-change heat transfer such as immersed type, heat pipe etc is applied in cooling of high-capacity power semiconductors of the main power system for the high speed train with the concentrated traction. In order to apply these phase-change cooling system to the high speed EMU to be developed, needed are technological researches of consideration of installing space, air passage, light weight material and miniaturization. Although this research establishes design specifications through theoretical analysis and computational analysis from the basic design process of the cooling system of the propulsion system for the high-speed EMU, when details design is completed, present improvement subject and optimum design before manufacturing the prototype of the cooling system on the basis of analysis results. And then, carried out will be the performance tests through prototype manufacture and reliability estimation by components of cooling system.

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Firms' Strategic Standardization : A Case Study by their Management Objectives (전략적 표준화의 유형별 기업사례분석)

  • Sung, Tae-Kyung
    • Management & Information Systems Review
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    • v.26
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    • pp.133-152
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    • 2008
  • In the knowledge and network economy, standards and standardization become an important factor in determining the competitiveness of nations and firms. This paper analyses some cases of firms' strategic standardization. We defined the concept of standards, standardization, strategic standardization, and standardization management, which have been unfamiliar in the academic society. The standardization strategy can be categorized into four types according to firm's management objectives or benefits, including technological innovation, market creation/extension. cost-down, and accreditation. This classification of standardization strategy is very useful in analysing the various kinds of the cases of strategic standardization implementation. We found that standards and standardization have a positive influence on firm's overall performance. In some cases, for example, Dell Computer, Sun Microsystems, Deere & Company, etc., strategic standardization plays a role as a key success factor(KSF).

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Giant Magnetoresistive Sensors for High Density Information Storage Applications (거대자기저항 센서를 중심으로 본 고밀도 정보저장기기용 기록헤드기술의 현황과 전망)

  • 김영근;정인섭;박태섭
    • Journal of the Korean Magnetics Society
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    • v.8 no.2
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    • pp.99-110
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    • 1998
  • MR head technology from the perspective of read sensor evolution was reviewed. AMR sensors have been developed for last two decades and successfully employed into information storage devices such as disk drives. Development of manufacturable GMR sensors is of emerging technological interest because GMR sensors can further meet the need of ultrahigh recording density. In this review, the mechanisms, materials systems, operating principles of both AMR an GMR sensors, and the head structures were discuseed. Constructing GMR heads with ultrathin sensor materials and complex topographical structures demands unique fabrication and design challenges. The commercialization of GMR heads can only be realized by the succesful implementations of high performance materials, advanced thin film processes, and stable head design.

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An Analysis of Major Failure Factors to Reduce the Dysfunctions of Electronic Commerce (전자상거래의 역기능 개선을 위한 주요실패요인 분석)

  • Han, Kyeong-Seok;Noh, Mee-Hyun
    • Asia pacific journal of information systems
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    • v.8 no.1
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    • pp.103-124
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    • 1998
  • The recent information society is affected by new technologies including EC(Electronic Commerce), CALS(Commerce At Light Speed), EDI(Electronic Data Interchange), telecommuting and teleconferencing. The research goal of this paper is to identify major failure factors to reduce the dysfunction of EC and to suggest possible strategies that overcome those obstacles. The research methodologies of major failure factors are very similar to those of critical success factors which were widely used in MIS research areas. Ideally EC provides the possibility of a win/win situation for vendors and consumers. A survey study was performed using questionnaires. The factor analysis was performed to identify failure factors. Several hypotheses were set up to identify the major failure factors to reduce the dysfunction of EC. The regession analysis was performed to test those hypotheses and to understand the relationships between the major failure factors identified and the performance variables such as satisfaction, usage, and usefulness. Finally, the paper suggests alternatives to activate EC in terms of regulations, social rules, a technological model, etc.

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Preliminary Structural Design of Wall-Frame Systems for Optimum Torsional Response

  • Georgoussis, George K.
    • International Journal of Concrete Structures and Materials
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    • v.11 no.1
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    • pp.45-58
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    • 2017
  • Recent investigations have pointed out that current code provisions specifying that the stiffness of reinforced concrete elements is strength independent, and therefore can be estimated prior to any strength assignment, is incorrect. A strength allocation strategy, suitable for preliminary structural design of medium height wall-frame dual systems, is presented for allocating strength in such buildings and estimating the dependable rigidities. The design process may be implemented by either the approximate continuous approach or the stiffness matrix method. It is based on the concept of the inelastic equivalent single-degree-of-freedom system which, the last few years, has been used to implement the performance based seismic design. The aforesaid strategy may also be used to determine structural configurations of minimum rotation distortion. It is shown that when the location of the modal centre of rigidity, as described in author's recent papers, is within a close distance from the mass axis the torsional response is mitigated. The methodology is illustrated in ten story building configurations, whose torsional response is examined under the ground motion of Kobe 1995, component KJM000.

The Performance of An Inspection System Providing 3D Spatial Proximity Data and Its' Design Considerations (3차원 근접정보를 이용한 검사시스템의 성능평가와 디자인 고려사항)

  • Jeong, Gyeong-Ho
    • Journal of the Ergonomics Society of Korea
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    • v.23 no.1
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    • pp.13-22
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    • 2004
  • Due to economical or technological reasons. humans are responsible for inspection functions in many cases. Humans. however. are rarely perfect. thus allowing non-confirming parts to be processed. As the attributes of interest or the variety of products increases. the inspection system becomes less effective because of the sensory and cognitive limitations of human inspectors. Any means that can support or aid the human inspectors is necessary to compensate for inspection difficulty. Augmented reality (AR) offers a new approach in designing an inspection system as a means to augment the cognitive capability of inspectors by providing the 3D spatial proximity between two information channels. The experimental results suggest that AR might be an effective tool that reduces inspection time without sacrificing the measuring accuracy.