Based on the observation that the moduli of a link variable on a cyclic group modify Connes' distance on this group, we construct several action functionals for this link variable within the framework of noncommut...Based on the observation that the moduli of a link variable on a cyclic group modify Connes' distance on this group, we construct several action functionals for this link variable within the framework of noncommutative geometry. After solving the equations of motion, we find that one type of action gives nontrivial vacuum solution for gravity on this cyclic group in a broad range of coupling constants and that such a solution can be expressed with Chebyshev's polynomials.展开更多
The semi-classical black hole tunneling radiation (Parikh-Wilczek tunneling proposal) is calculated undera minimal length uncertainty analysis.It is shown that,the generalized second law of thermodynamics may bound th...The semi-classical black hole tunneling radiation (Parikh-Wilczek tunneling proposal) is calculated undera minimal length uncertainty analysis.It is shown that,the generalized second law of thermodynamics may bound thetunneling probability radiation of a Reissner-Nordstrom black hole radiation.展开更多
We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar fi...We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar field associated to dark energy and meanwhile the scalar field evolves in a power law potential. Since the dynamics of this system is dominated by an attractor solution, the mass of dark matter particles is forced to change with time as to ensure that the ratio between the energy densities of dark matter and dark energy becomes a constant at late times,and one thus solves the cosmic coincidence problem naturally. We then apply a statefinder diagnostic to this coupled quintessence scenario. It is shown that the evolving trajectory of this scenario in the s-r diagram is quite different from those of other dark energy models.展开更多
The purpose of this study was to analyze the relationship between psychosocial working conditions and perceived safety climate onboard the Swedish merchant fleet. Data was collected by a cross-sectional survey. The sa...The purpose of this study was to analyze the relationship between psychosocial working conditions and perceived safety climate onboard the Swedish merchant fleet. Data was collected by a cross-sectional survey. The sample consisted of 640 Swedish employed engine room officers. A strong relationship was found between the psychosocial working conditions and perceived safety climate onboard (RZ = .204; P 〈 .001). While role conflict and role ambiguity showed a negative association, social support associated positively with safety climate onboard, lob demands and control showed no relation to safety climate. The conclusion is that the safety climate onboard is strongly associated with social and relational factors.展开更多
基金国家攀登计划,国家自然科学基金,Doctoral Programme Foundation of Institution of Higher Education of China
文摘Based on the observation that the moduli of a link variable on a cyclic group modify Connes' distance on this group, we construct several action functionals for this link variable within the framework of noncommutative geometry. After solving the equations of motion, we find that one type of action gives nontrivial vacuum solution for gravity on this cyclic group in a broad range of coupling constants and that such a solution can be expressed with Chebyshev's polynomials.
文摘The semi-classical black hole tunneling radiation (Parikh-Wilczek tunneling proposal) is calculated undera minimal length uncertainty analysis.It is shown that,the generalized second law of thermodynamics may bound thetunneling probability radiation of a Reissner-Nordstrom black hole radiation.
文摘We investigate a coupled quintessence scenario, which can provide a natural solution to the cosmic coincidence problem. We assume that the mass of dark matter particles depends on a power law function of the scalar field associated to dark energy and meanwhile the scalar field evolves in a power law potential. Since the dynamics of this system is dominated by an attractor solution, the mass of dark matter particles is forced to change with time as to ensure that the ratio between the energy densities of dark matter and dark energy becomes a constant at late times,and one thus solves the cosmic coincidence problem naturally. We then apply a statefinder diagnostic to this coupled quintessence scenario. It is shown that the evolving trajectory of this scenario in the s-r diagram is quite different from those of other dark energy models.
文摘The purpose of this study was to analyze the relationship between psychosocial working conditions and perceived safety climate onboard the Swedish merchant fleet. Data was collected by a cross-sectional survey. The sample consisted of 640 Swedish employed engine room officers. A strong relationship was found between the psychosocial working conditions and perceived safety climate onboard (RZ = .204; P 〈 .001). While role conflict and role ambiguity showed a negative association, social support associated positively with safety climate onboard, lob demands and control showed no relation to safety climate. The conclusion is that the safety climate onboard is strongly associated with social and relational factors.