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With the fast development of the social economy and the improving diverse material life, the demand for a much higher quality of living environment is increasing, thus, the importance to design the urban landscaping for a city is superior to that of the city planning and its ecological environment. Considering the circumstances that the extensive pattern of management in urban landscaping and the...
We present an approach for generation, amplification, and compression of 4–12 μm pulses by tailoring the phase matching of ZGP in broadband-pumped dual-chirped optical parametric amplification and by indirect pulse shaping.
Under the three-phase unbalanced grid condition, the commonly used controller design methods of three-phase voltage source rectifiers (VSR) are based on the instantaneous power model and the current and voltage double-closed loop control structure. The inner current loop proportional integral (PI) controllers are designed for the positive- and negative-sequence current components, separately, therefore,...
Traction system is the “heart” unit of railway vehicles, its performance is crucial to the improvement of vehicle performances. With the rapid development of controller chips, the high performance control algorithms of induction motors have been applied into the traction systems. Model predictive control has some advantages, such as simple principle, easy modeling, handling nonlinear constraints,...
Induction motors consume most of the industrial power electricity, so it is very meaningful to improve the operation efficiency of induction motors. A simplified loss model efficiency optimization algorithm for vector control induction motor drives is proposed in this paper, in order to improve the operation efficiency of induction motors via the simplest algorithm and the least computation load....
A lot of research has been proposed to improve network performance in the data center. However, with the development of distributed applications, these applications face a new performance bottleneck since existing solutions almost ignore the application level optimization. The concept of coflow has been proposed which provides a chance for us to optimize network in application level rather than individual...
This Polyimide film has excellent electrical properties and it serves as an important insulating material which is widely used in the variable-frequency motor and wind generator. Since high temperature is a significant reason for degradation in insulation, the space charge distributions of polyimide (PI) films in high temperature condition is worth investigating. Under different temperature, the conductivity...
The ideal Gaussian pulse can be more convenient to simulate the excitation of electromagnetic waves and its propagation characteristics, but the pulse and the actual local discharge current waveform is not exactly the same. At the same time, most of the previous research contents have adopted the simplified GIS simulation model, which does not take into account the influence of the arc of the basin...
Conventional sliding mode control (SMC) is so-called robust to the system uncertainty and the external disturbance, however, it requires the knowledge about the upper bound of uncertainties and external disturbances. In the practical system, uncertainties and external disturbances are often unknown. A adaptive backstepping sliding mode controller (ABSMC) is proposed to deal with the uncertainty in...
A novel voltage equalizer called Multilevel Architecture is proposed for series-connected photovoltaic (PV) system to prevent negative influence of mismatch issues. This undesirable mismatch triggers multiple power maxima in PV string P-V characteristics, encumbering maximum power points tracking (MPPT) algorithms. This paper designed a control scheme for isolated-port flyback converter operating...
Inter-City Hybrid electric multiple unit (EMU) is very good choice for the cross line transportation between electrified and non-electrified railways. This paper proposes an on board energy storage system (ESS) for inter-city hybrid EMU to absorb braking energy and feed the train for the non-electrified lines. The system and its working modes are introduced, as well as the system modeling. Taking...
A new method, based on support vector machines (SVMs) and genetic algorithm (GA), is proposed for automatic Intra-Pulse modulation recognition (AIMR). In particular, the best feature subset from the combined pulse descriptor word (PDW) feature set and time-frequency feature set is optimized using genetic algorithm. Compared to the conventional decision-theoretic method, the method proposed avoids...
In this paper, a method of analyzing the equestrian sport based on body sensor network is introduced. This method uses inertial sensors to analysis the motion characteristics of the key parts in the process of equestrian sport, so as to provide references for the correction of equestrian posture. This paper first arranges wireless sensor nodes on the surface of the key parts by analysing the motion...
A novel space vector PWM (SVPWM) strategy is proposed in this paper to balance the neutral-point voltage (NP) and the floating capacitor voltage for five-level active neutral-point-clamped (ANPC) converter. There are two different switching sequences in each small area. According to the NP offset, different switching sequences are used to control the NP voltage. Since the charge-discharge of the floating...
Software-Defined Networking (SDN) is an innovational network architecture introduced a couple of years ago. It gives network administrators the ability to directly control the whole network by programming on a centralized controller, without manually configure each device. However, new security challenges come out with SDN development. One significant challenge is to design a secure firewall specifically...
While running on the track, mid-low speed maglev has to deal with the disturbance from Guideway steps and gaps, which may bring impulse to the suspension system. In order to suppress the influence of the guideway gaps to the vehicle, enhance the reliability of the system and bring passengers comfort, the article puts forward a compensation algorithm, which judges the guideway steps according to the...
with the development of electronic information technology, the heating problem in microwave components is becoming more and more important. Reducing dielectric loss is an effective way to reduce component heat. Bi1−xYxFeO3 (x=0.02, 0.04, 0.06, 0.08) ceramics were synthesized by traditional state solid method, and the effects of Y3+ ions on magnetic and dielectric properties were studied. The XRD results...
Magnetic and dielectric properties of multiferroic (1−x)BiFeO3−xBaFe12O19 (x=0.03, 0.05, 0.07, 0.09 wt%) solid solution synthesized by state solid were investigated. Morphology of the sample is determined by SEM, indicating that the grain has been shrink, and all samples have been irregular. With increasing of BaFe12O19, saturation magnetization increased from 0.07 to 0.7 emu/g, and coercivity increased...
Over-exposed region detection is commonly used for image editing and other applications such as over-exposure corrections. In broadcasting, over-exposed regions in image/video can be detected and corrected prior to sending them to consumers. However, the current detection of over-exposed regions is sometimes inaccurate. The detected over-exposed regions are susceptible to noise and scattered. In this...
To meet the requirements of improving performances and realizing miniaturization and integration for microwave devices, low temperature co-fired ceramic (LTCC) technology emerged and has been widely investigated. In present work, with 2.5wt% BBSZ additive, low temperature co-fired Sn4+ and Ca2+ ions co-doped Y3Fe5−2xSnxCaxO12 (x=0.0∼0.8 with 0.2 step) ferrite materials were synthesized using solid...
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