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In order to measure the open-ended fund's liquidity risk accurately, the method of non-liquidity and VaR are used in this paper. We measure the liquidity risk of open-ended fund with non-liquidity indicators, fitting these non-liquidity indicators of sample funds with GARCH model under normal distribution, t-distribution and generalized error distribution (GED), then put the fitting parameters into...
A three-phase copper bus bars arrangement in low voltage system is investigated. Each phase main conductor consists in one up to four sub-conductors with rectangular cross sections. The short circuit may introduce great hazardous forces. In order to ensure bus bars and power system operate in security, verifying of short-circuit dynamic stability should be made. Three methods of calculating short-circuit...
To measure the height and wear of the diamond abrasive, a new technique based on computer vision is presented in this paper. Firstly, the computer vision system is designed. The height evaluation of abrasives and the calibration of the imaging set-up are introduced in detail. Secondly, we adopt the sequential similarity detection algorithm to get corresponding pixels in the left and right image. Finally,...
The paper selects the panel data of 14 leading banks in Chinese banking market in 1996-2007 periods and makes analyzes of the impact of foreign financial institution entry on the efficiency of Chinese banking industry. And the result shows that the X-efficiency of Chinese commercial bank is continuously upgrading and the efficiency of banks with foreign strategic investors is higher than that without...
Both finite volume method and finite difference method are adopted to disperse 1-D unsteady flow and sediment equations, for establishing 1-D dam-break flow and sediment numerical model. Based on the sediment data of Xinji reservoir of different operating years, the flood after dam-break is simulated by using this model. Compared with dam break results of initial impoundment period, it shows the influence...
A new load flow method for large shipboard power system with multiple generators which combined Gauss-Seidel method and forward-backward method is presented. In the proposed method, an shipboard power system is divided into a main power supply network and several radial distribution networks, which are deal with respectively. The forward-backward sweep method is used to solve the power flow for each...
The history of ACM Turing Award presentation, from one perspective, presents the development of computer science and technology. Moreover, the winners of ACM Turing Award enlighten us greatly. This paper performs statistics and analysis for the nationality, education background, universities, specialty and ages when they made contributions of the Turing Award winners between 1966 and 2006. From their...
The thermal pollution due to the cooling water project of the phase IV expansion project of Yangluo power plant is studied using a 2-D horizontal mathematical model, to predict the flow and temperature fields of the warm water outflow from the power plant. Based on the calculated area of thermal pollution of this cooling water project, proposals to reduce the influences of the thermal pollution of...
According to the Gauss curvature of each node on 3-D basic body surface, the indexes such as pheromone and volatilization coefficient are determined. The ant colony algorithm is designed and used. In the algorithm the selected nodes collection are changed every time. The circle times are determined based on the percent of desired nodes account for different areas. At last the basic body surface is...
For the purpose of improving the localization accuracy of bistatic sonar in some districts such as baseline district, side districts of transmitting and receiving stations, the most effective method is to increase the amount of the transmitting and receiving stations so that the multistatic sonar system is formed. Multistatic TOL algorithm and BOL algorithm, which are comparatively mature by far contains...
Batteries are widely used in quite a few areas, including in the electric auto industry. As the voltage of the batteries are ever-changing, which drops from a high value to a low value, kinds of regulators are utilized to keep the output voltage changing in an acceptable scope. However, the stress on switches produced by the currents in the circuits is much stronger than the capabilities of the switches,...
In this paper, a modeling method for the data analysis solution is presented and the enterprise level of the data warehousing problem is introduced. The method includes the processes of the requirement elicitation, analysis stage and the initial design of the data warehouse. The extended operation model which can satisfy the need of the data warehouse is also presented in this paper because that it...
This paper focus on the most important aspects of the bi-directional DC-DC converter in the hybrid electric vehicle(HEV) for the project applications.The different operating modes of converter are introduced under all HEV's work condition.Based on summarization, the demerits including low efficiency at light load and the uncontrolled discontinuous current when charging for the battery are derivated...
The mathematical models of five-phase permanent magnet synchronous motor (PMSM) in abc frame and alphabeta frame are established, and the relationships between the torque and fundamental components, loss and harmonic components are revealed. To suppress the high third harmonic current appeared in five-phase machine especially, a novel space vector pulse width modulation (SVPWM) method which has a...
To overcome the duty ratio limitation issue existing in dual switch forward converter (DSFC) and improve efficiency, a novel resonant reset asymmetrical DSFC was proposed, which, compared with the former resonant reset DSFCs, maintains the advantage of lowering voltage stress on each switch, at the same time, possesses the merits as duty ratio can exceed 50% and conventional PWM operation capability...
This paper presents a comprehensive research on torque ripples of brushless dc motor drive in conduction region based on the mathematical models.The phenomenon of torque ripples of conduction exists because of diode freewheeling happened under the conventional PWM schemes. Through theoretical and mathematical analysis, a new method for reducing the torque ripple in brushless dc motors with a single...
High dc gain step-up dc-dc converter continues drawing lots of interests in on-line UPS systems to interface the battery power to unity. Conventional methods, in which using non-isolated converters including cascade converters, can achieve high dc gain but compromise efficiency, while the situation of employing isolated converters is just opposite. To combine the merits of these two type converters...
In this paper, a new direct torque control (DTC) method of multi-phase induction motor for electrical propulsion is proposed. The classical DTC method for three phase induction motor uses the hysteresis-loop controller based on the switching table, in which the stator flux and torque ripple exists obviously. The new DTC method mentioned above applies the space vector PWM (SVPWM), which can achieve...
In this paper, a novel five-phase five-level inverter based on H-bridge is proposed. Then, the PWM control strategies of this inverter are researched. As the five-phase five-level inverter has 3125 space voltage vectors, it makes SVPWM algorithm extraordinarily complex and too difficult to implement. So, it is a feasible control scheme to adopt carrier-based PWM method. According to phase-shift SPWM...
This paper presents a comprehensive research on torque ripples of brushless dc motor drive in conduction region based on the mathematical models.The phenomenon of torque ripples of conduction exists because of diode freewheeling happened under the conventional PWM schemes.Through theoretical and mathematical analysis, A new method for reducing the torque ripple in brushless dc motors with a single...
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