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A high performance npn bipolar transistor has been demonstrated in a 0.13µm SOI SmartMOS™ technology. This novel bipolar transistor consists of a shallow emitter confined by shallow trench isolation (STI), a base with multiple regions each serving a different purpose without compromising one another, and a lightly doped collector region surrounded by continuous p-type regions biased with the base...
A low-jitter and wide output frequency range ADPLL was proposed in this paper. The adopted PFD based on sense-amplifier flip-flop (SAFF) can effectively improve the jitter performance. The novel DCO with cascading structure consists of a coarse-tuning delay chain and a fine-tuning interpolator, obtaining both wide frequency tuning range and high resolution. A time-amplifier based sub-exponent TDC...
A low-jitter and wide output frequency range ADPLL was proposed in this paper. The adopted PDF based on sense-amplifier flip-flop (SAFF) can effectively improve the jitter performance. The novel DCO with cascading structure consists of a coarse-tuning delay chain and a fine-tuning interpolator, obtaining both wide frequency tuning range and high resolution. A high-resolution TDC was employed in this...
In order to improve the intelligent operation level of the motor operation mechanism of 40.5kV vacuum circuit breaker, and finish the opening operation of the circuit breaker under the preset stroke curve, the relationship between winding voltage and speed of motor is studied in the running process. The speed control method of motor by controlling the voltage at the specified point is proposed. Aiming...
In this paper, researches were carried on the breakdown characteristics of short gap SF6/ CF4, under the flat plate and needle board electrodes, the breakdown voltage of SF6/CF4 gas mixetures was measured when partial pressure ratio of SF6 is from 0% to 100% and the pressure is from 0.1MPa to 0.4MPa, the effects of the gas pressure and other factors on insulation performance of SF6 and its mixed gas...
The Redlich-Kwong state equation of the real gas and the governing equations of the flow field were combined to solve the problem. The distribution of physical parameters of the interrupter was attained under the condition of the circuit breaker in small capacitive current interruption by analysis of the 126kV capacitor group SF6 gas circuit breaker arc extinguishing chamber in air flow field, which...
For monitoring deformation state of transformer winding, the online monitoring method based on short circuit reactance is researched in this paper. The mathematic model of short circuit reactance is established, and online calculation method is researched. Simulation model of short circuit reactance is built based on MATLAB. The online test system of short circuit reactance is designed. Aiming at...
Based on dynamic characteristic of microscopic particles in discharge process, streamer discharge model is set up. Combining finite element method and flux corrected transport method, the paper simulate the streamer discharge process at SF6/ N2 with mixing ratio of 50%:50%. On this basis, experimental platform for gas discharge is set up, and breakdown voltages of SF6/N2 gas mixtures are measured...
Grounding grids play a very important role for the safe operation of the substation. When grounding grids fault occurred, resulted in abnormal surface potential or uneven distribution, and that will be a serious threat to personnel and equipment. Considering the influences of leakage current and displacement current in the soil, establish mathematical model of transient electric field. Combining with...
Polarity reversal is a special condition of converter transformer bushing that needs to bear both DC voltage and AC voltage in an instant polarity reversal, and the time of polarity reversal effects the bushing of the electric field distribution simultaneously. The finite element method is used to analyze the ±600kV converter transformer bushing in different polarity reversal time under the condition...
For the study of the discharge parameters characteristics of different proportions of SF6/N2 gas mixture, thus the reason of synergistic effect was analyzed from the perspective of inter-particle interaction. With the ‘two-term’ approximation to solve the Boltzmann equation, the discharge parameters of different mixing ratio of the SF6/N2 mixtures can be acquired including the electron energies distribution...
Vehicle scheduling of urban distribution is an important element of the logistics center's operation. The total scheduling cost is not only influenced by the satisfaction of customer service time window and the effective utilization of vehicle capacity, but also is closely related to the traffic flow, road capacity, vehicle saturation degree of intersection, traffic lights and road rules in actual...
In the product life cycle, design reuse can save cost and improve existing products conveniently in most new product development. To retrieve similar models from big database, most search algorithms convert CAD model into a shape descriptor and compute the similarity two models according to a descriptor metric. This paper proposes a new 3D shape matching approach by matching the coordinates directly...
The aim of simulation technique for production line is to find out the most feasible scheme which designers made for the project. Simulation technique can verify the actual effect of the project from the schemes. Combined with the actual production mode, the article analyzed the bottleneck of production efficiency under different shifts. It mainly discussed the value of simulation technology for production...
Accurate modeling of Electroencephalography (EEG) signals is an important problem in clinical diagnosis of brain diseases. The method using support vectors machine (SVM) based on the structure risk minimization provides us an effective way of learning machine. But solving the quadratic programming problem for training SVM becomes a bottle-neck of using SVM because of the long time of SVM training...
Stock investment is one of the available conventional financial commodities in the investment market. The individual price of stocks including stocks in the field of industrial, medical, financial, overall, etc. Is subject to many different aspects. The relationship between aspects, the international economy, and the stock price is complex and is not easy to be categorized. Moreover, the trend of...
Web objects, often associated with descriptive text documents, are increasingly being geo-tagged. A spatial keyword top-k query retrieves the best k such objects according to a scoring function that considers both spatial distance and textual similarity. However, it is in some cases difficult for users to identify the exact keywords that describe their query intent. After a user issues an initial...
This paper proposes a novel query paradigm, namely reverse keyword search for spatio-textual top-k queries (RST Q). It returns the keywords under which a target object will be a spatio-textual top-k result. To efficiently process the new query, we devise a novel hybrid index KcR-tree to store and summarize the spatial and textual information of objects. To further improve the performance, we propose...
A novel quadrature multi-loop CMOS ring oscillator, employing a current compensation technique and offering a wide frequency tuning range, low power consumption and small silicon area, is proposed. A current mirror on the output terminal is used to reduce the mismatch between the source-follower and the latch inverter, and it also helps to shrink the dimensions of the source-follower in the phase-shift...
The optimization of energy efficiency (EE) in spectrum-sharing networks has received increasing attention. While much effort has been devoted to the network-side overall EE, the fairness of EE among users has not been adequately concerned. Due to the complicated interference between different users, the global optimality of power allocation problems for achieving proportional, harmonic, and max–min...
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