30,352 research outputs found

    Chemisorption on a model bcc metal

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    The system considered here is that of a single atom with one energy level chemisorbed on the (001) surface of a model bcc metal. We present the change in the density of electronic states Δn (E) due to chemisorption for two cases: one when the adatom is bound to a single substrate atom in the "on‐site" configuration and the other when it is bound to four substrate atoms in the "centered fourfold site." In principle, this change in the density of states Δn can be related to the results of photoemission measurements

    "Heterotic" Discrete Flavor Model

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    We present an extended 331 model with TT' discrete flavor symmetry that simultaneously explains the need to have exactly three generations and provides acceptable quark and lepton masses and mixings. New fermionic states and gauge bosons are predicted within the reach of the LHC. We discuss the relevance to the 126 GeV scalar discovered at the LHC.Comment: 13 pages, v3: version to appear in PR

    Composite load spectra for select space propulsion structural components

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    The work performed to develop composite load spectra (CLS) for the Space Shuttle Main Engine (SSME) using probabilistic methods. The three methods were implemented to be the engine system influence model. RASCAL was chosen to be the principal method as most component load models were implemented with the method. Validation of RASCAL was performed. High accuracy comparable to the Monte Carlo method can be obtained if a large enough bin size is used. Generic probabilistic models were developed and implemented for load calculations using the probabilistic methods discussed above. Each engine mission, either a real fighter or a test, has three mission phases: the engine start transient phase, the steady state phase, and the engine cut off transient phase. Power level and engine operating inlet conditions change during a mission. The load calculation module provides the steady-state and quasi-steady state calculation procedures with duty-cycle-data option. The quasi-steady state procedure is for engine transient phase calculations. In addition, a few generic probabilistic load models were also developed for specific conditions. These include the fixed transient spike model, the poison arrival transient spike model, and the rare event model. These generic probabilistic load models provide sufficient latitude for simulating loads with specific conditions. For SSME components, turbine blades, transfer ducts, LOX post, and the high pressure oxidizer turbopump (HPOTP) discharge duct were selected for application of the CLS program. They include static pressure loads and dynamic pressure loads for all four components, centrifugal force for the turbine blade, temperatures of thermal loads for all four components, and structural vibration loads for the ducts and LOX posts

    LHC Higgs Production and Decay in the T' Model

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    At s=7\sqrt{s} = 7 TeV, the standard model needs at least 10(fb)110\, (fb)^{-1} integrated luminosity at LHC to make a definitive discovery of the Higgs boson. Using binary tetrahedral (TT^{'}) discrete flavor symmetry, we discuss how the decay of the lightest TT' Higgs into γγ\gamma\,\gamma can be effectively enhanced and dominate over its decay into bbˉb \, \bar{b}. Since the two-photon final state allows for a clean reconstruction, a decisive Higgs discovery may be possible at 7 TeV with the integrated luminosity only of 1(fb)1\sim 1\, (fb)^{-1}.Comment: 17 pages, 9 figure

    Off-diagonal hyperfine interaction between the 6p1/2 and 6p3/2 levels in 133Cs

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    The off-diagonal hyperfine interaction between the 6p1/2 and 6p3/2 states in 133Cs is evaluated in third-order MBPT giving 37.3 Hz and 48.3 Hz, respectively, for second-order energies of the 6p3/2 F=3 and F=4 levels. This result is a factor of 10 smaller than one obtained from an uncorrelated first-order Dirac-Hartree-Fock calculation and used in the analysis of a recent high-precision (< 2 kHz) measurement of the 6p3/2 hyperfine structure [Gerginov et al. Phys. Rev. Lett. 91, 72301 (2003)]. The factor of 10 difference has negligible effect on the conclusions of the recent experiment but will become important for experiments carried out at a precision of better than 1 kHz

    Preparedness for ASEAN Economic Community: perspective of Malaysian SME manufacturers

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    The ASEAN Economic Community (AEC) initiative poses both significant opportunities and difficult challenges to the Malaysian small and medium-sized enterprises (SME) communities. This research sets out to study the preparedness of local SMEs for the impact of the AEC implementation and their capabilities to capitalize on the opportunities. The manufacturing sector has been selected for study and the research efforts focus on the procurement function in the organizations. Procurement competences are gauged from four key perspectives: supplier relationship building, supply optimization, supplier capability auditing and purchasing integration. SMEs’ preparedness in this critical business function to compete and exploit opportunities in a post-AEC era, is investigated. Using a mixed research strategy approach, the study explores SME procurement practices in the two biggest manufacturing sub-sectors in Malaysia: Resource-based (RB) and Electrical and Electronics (E&E). The study also compares and contrasts locally-owned and foreign-owned SME manufacturing operations in these two sub-sectors. It investigates possible differences in the extent of SME preparedness in different industrial and organizational context. The results of the study provide an understanding of the key factors which have contributed to variations in SME’s attitude towards policy awareness. The findings also highlight the procurement competencies that Malaysian SMEs in the manufacturing sector could improve in order to compete effectively post-AEC

    Sustainability of cultural influences on decision-making: a case study of institutional elderly care in China

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    The world is facing a situation without precedent: We will have more elderly people than children and more people at extreme old age than ever before. It is not the scope of this paper to address the breadth of the issues brought about by the transforming demographic force of population ageing in the world. This paper focuses on the exploration of attitudinal support for institutional elderly care services in China. China is chosen for the study as it is a developing country with one of the fastest aging society in the world whilst its elderly care infrastructure is still at its infancy in comparison with the developed countries. The perceptions of individuals with different demographic characteristics are studied to understand the influence and stability of Chinese cultural beliefs on decision-making for elderly care services. An online survey was used to collect both quantitative and qualitative data. Data was interpreted in the context of the Chinese traditional practices. Findings revealed majority respondents were not supportive of institutional elderly care due to traditional values, social stigma, superstitions, the tradition of collective decision-making, perception of current institutional care’s quality and financial ability. However, the study also revealed certain demographic profile responded positively to institutional care, providing informative inputs to more targeted marketing efforts for investors. Findings also contribute to the knowledge base of cultural understanding for elderly care business models
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