1,686 research outputs found

    Application of Analytic Hierarchy Process (AHP) in shipyard project investment Risk Recognition

    Get PDF
    Risk Recognition is an important part in shipyard project risk management. The purpose of this paper is to explain how to identify risks by means of AHP. Firstly, we analyzed briefly the superiority of AHP in shipyard project risk Recognition; secondly, expounded the basic steps of risk Recognition based on AHP in shipyard project investment; then we proposed the principle and tips of applying AHP in identifying project risks by demonstrating a case of shipbuilding base. To prove the validity of AHP, we have identified the risk factors of the Shipyard project that mentioned in the case above, and have also calculated the influence weights taxis of dominating risk factors to the general risk. Key words: Shipyard Project Investment; AHP; Risk Recognition; Risk Factor

    Mathematical Model to Predict Preheating Time and Temperature Profile in Boxed-Heart Square Timber during Preheating

    Get PDF
    The objective of this study was to develop a two-dimensional mathematical model that can beused to calculate the heat transfer in larch boxed-heart square timber during the preheating process. The preheating time obtained with the calculations agreed with the experimental results. Both experiments and calculations indicated that it took about 6.5 h for the center of the timbers (120 mm thick 120 mm wide) to reach ambient temperature, suggesting that the model can be used to accurately estimate preheating times. During the preheating process, the simulated core temperature of the wood agreed with the experimental result. However, for the remaining locations, the relative error was rather large, with the value first increasing and then decreasing with time. Therefore, the model can only be used to accurately estimate temperature at the core region of the wood. Furthermore, the results suggested that MC had no significant effect on preheating time

    Quantum theory of electronic double-slit diffraction

    Full text link
    The phenomena of electron, neutron, atomic and molecular diffraction have been studied by many experiments, and these experiments are explained by some theoretical works. In this paper, we study electronic double-slit diffraction with quantum mechanical approach. We can obtain the results: (1) When the slit width aa is in the range of 3λ∼50λ3\lambda\sim 50\lambda we can obtain the obvious diffraction patterns. (2) when the ratio of d+aa=n(n=1,2,3,⋅⋅⋅)\frac{d+a}{a}=n (n=1, 2, 3,\cdot\cdot\cdot), order 2n,3n,4n,⋅⋅⋅2n, 3n, 4n,\cdot\cdot\cdot are missing in diffraction pattern. (3)When the ratio of d+aa≠n(n=1,2,3,⋅⋅⋅)\frac{d+a}{a}\neq n (n=1, 2, 3,\cdot\cdot\cdot), there isn't missing order in diffraction pattern. (4) We also find a new quantum mechanics effect that the slit thickness cc has a large affect to the electronic diffraction patterns. We think all the predictions in our work can be tested by the electronic double-slit diffraction experiment.Comment: 9pages, 14figure

    Critical chain construction with multi-resource constraints based on portfolio technology in South-to-North Water Diversion Project

    Get PDF
    AbstractRecently, the critical chain study has become a hot issue in the project management research field. The construction of the critical chain with multi-resource constraints is a new research subject. According to the system analysis theory and project portfolio theory, this paper discusses the creation of project portfolios based on the similarity principle and gives the definition of priority in multi-resource allocation based on quantitative analysis. A model with multi-resource constraints, which can be applied to the critical chain construction of the A-bid section in the South-to-North Water Diversion Project, was proposed. Contrast analysis with the comprehensive treatment construction method and aggressive treatment construction method was carried out. This paper also makes suggestions for further research directions and subjects, which will be useful in improving the theories in relevant research fields

    Dirac Equation at Finite Temperature

    Full text link
    In this paper, we propose finite temperature Dirac equation, which can describe the quantum systems in an arbitrary temperature for a relativistic particle of spin-1/2. When the temperature T=0, it become Dirac equation. With the equation, we can study the relativistic quantum systems in an arbitrary temperature.Comment: arXiv admin note: text overlap with arXiv:1005.2751, arXiv:hep-ph/0004125, arXiv:hep-ph/0005272 by other author
    • …
    corecore