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The extraction method of induction motor’s fault character based on coordinate transformation could restrain the influence of fundamental component leakage by translating fundamental component into DC component. The amplitude of the fault character frequency component was inaccurate by spectrum analysis taking no account of the leakage of itself. So rotor fault diagnosis method of induction motor based on discrete spectrum correction technology is proposed. This method which did not depend on spectral function of the window function improved the traditional phase difference correction method, and the stator current signal analysis by means of an appropriate window function is performed to reduce the interference between each frequency. The proposed method could detect the existence of fault character frequency component and its frequency and amplitude. The simulation and experimental results indicated that using this method could get better precision of frequency and amplitude of the fault character frequency component.

According to the characteristic of the shipboard power system, heuristic search for fast tracking shipboard power system network topology is introduced. Using for reference of the methods of fault diagnosis of the power systems, the Petri net technology is used to fault location and removal of uncertain and fault signals, which can modify the topology analysis results. Setting the topology analysis and remodel based on Petri net of the typical shipboard power system for example, the results is validated.

We frist establish the evaluation index system according to the characteristics of the simulation training system through analysis, and second , we calculate the index weight use improved gray analytic hierarchy process which simplify the steps of the original analytic hierarchy process. Third we use the Delphi method to establish the membership degree of every evaluation index, and finally we use fuzzy comprehensive evaluation method to get the evaluation results of the simulation training system, the results show that the evaluation model is consistency to the expert assessment , meet the actual needs, is an effective method of power system simulation training assessment.

Rich phenomenology is generally expected if the heavy neutrinos responsible via the seesaw mechanism for the small neutrino mass observed in neutrino oscillations are not much heavier than the electroweak scale. A model with this feature built in has been suggested recently by Hung. We analyze the lepton flavor structure in gauge interactions and calculate the branching ratios for the rare decays due to the gauge interactions in this model.

It is known to all that the right-handed neutrinos can not be produced and detected at present and future colliders in the most popular see-saw scenarios for the simple reason that they are too heavy in these models. However, a simple extension of the Standard Model (SM) particle content [1], including mirror fermions,two triplet and one singlet Higgs fields, leads to a scenario in which the see-saw mechanism [2] is realized with the Majorana mass of the right-handed neutrino being of the order of the electroweak scale or smaller. Motivated by this viewpoint, we have studied the model suggested by Hung recently and given the constraints on the physical parameters in gauge interactions of leptons in this model.

The smallness of neutrino masses is naturally explained by the seesaw mechanism, which is usually implemented by assuming a small Dirac mass of order charged leptons’ and a large mass of sterile neutrinos of order GUT scale [1]. This makes heavy neutrinos experimentally inaccessible. If heavy neutrinos have a mass of order electroweak scale, they could be detected at high energy colliders. A model with this feature built in has been suggested recently by Hung. We analyze the constraints on the unknown parameters in the decay and .

The lepton flavor violating process has been previously studied in a model of electroweak-scale right-handed neutrinos. We have calculated the decay amplitude in unitarity gauge [1]. In this paper, we recalculate the amplitude in gauge but in small neutrino mass limit. The final result which the cancellation of the dependence in is different from the obtained amplitude and the technical points in the previous work.

Rich phenomenology is generally expected if the heavy neutrinos responsible via the seesaw mechanism for the small neutrino mass observed in neutrino oscillations are not much heavier than the electroweak scale. A model with this feature built in has been suggested recently by Hung. We analyze the lepton flavor structure in gauge interactions and calculate the branching ratios for the decays due to the gauge interactions in this model.

The best is to read these instructions and follow the outline of this text. Mg-RE-B alloy with minuteness particle structure (MPS) were prepared by ingot metallurgy including as-cast and hot-extruded processing, and the microstructure and mechanical property of Mg-6RE-3B2O3 (wt%) alloys were investigated before and after hot-extruded. The Mg-RE-B alloy has satisfied grain size and particle structure, went with excellent mechanical property of tensile yield strength of 520 MPa and elongation of 5% at room temperature. The MPS Mg-RE-B alloy is a promising candidate among lightweight structural materials

Loading management is one of the most important technologies for ship power system. Reasonable distribution of electric energy to the loading can achieve the goal of optimal energy schedule and its primary issue is to make a reasonable loading priority evaluation. This paper analyzed the shortcomings of the loading priority evaluation using the AHP and proposed a kind of algorithm of property weight evaluation based on PRISM classification, effectively combing expertise and characteristics of the objective data itself together. The results show that: the loading priority of ship power system is mainly affected by two properties of demand urgency and vulnerability. The results of various algorithms are basically consistent with the above conclusion, which proved the correctness of the algorithm. Comparison among various evaluation results tables shows that for the same weight measurement standard using different classification algorithm or property reduction algorithms, the results of its loading priority evaluation slightly differ.

For development of high strength magnesium alloys, a melt stirring method was employed to Mg-Al and Mg-RE (rare earth metal) alloys. As reinforcement particle, B2O3 powder was added into melts and stirred at 953K in 10 or 20 minutes with argon atmosphere. The grain sizes of both alloys were decreased by 3wt% B2O3 addition. These results show that B2O3 have grain refinement effects to magnesium alloys. Micro Vickers hardness of Mg-Al alloy was increased by 3wt% B2O3 addition. On the other hand, the hardness of Mg-RE alloy was decreased by B2O3. Though addition of B2O3 into Mg-Al and Mg-RE systems make grain size to fine, the hardness of Mg-RE alloys decreased. The tensile properties of Mg-RE alloys with B2O3 were extremely improved by extrusion process.

In the present study, the conventional process of Compo-casting was carried and the microstructural and mechanical propertied were then investigated. The matrix alloy used was Mg- 6Al, and B2O3 was added into Mg-Al alloys was investigated at two levels of 3 and 6wt%. The other experimental materials were NaCl and CaCl2. The microstructures were of the samples analyzed with Optical Microscopy, SEM and XRD, and the mechanical properties were determined by micro-hardness and tensile test. The results showed that the mechanical properties of Mg- 6Al- 3B2O3- 1NaCl- 1CaCl2 increased and the microstructure was satisfactory, for a cast alloy, i.e.the tensile strength was 175MPa.