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Aiming at the influence of driving speed, air temperature, wind speed and other nonlinear factors on driving, the traditional PID has poor ability to adjust adaptively temperature, which it is difficult to meet the needs of self-adaptive temperature adjustment about the electric vehicle gloves. So a temperature control and thermal insulation system based on adaptive fuzzy PID for electric vehicle gloves is designed in this article. According to the fuzzy rule, the error and the rate of error change between the actual temperature and the set value of gloves are deduced, the increment DKp, DKi, DKd of Kp, Ki, Kd are obtained, then the PID control parameter Kp, Ki, Kd can be further adjusted to meet the needs of adaptive adjusting gloves temperature in different environments. The system adopts STM32F103C8T6 micro controller, voice recognition and player module, human body induction module and other sensors for hardware design, software design and experimental verification. Experimental result shows that contrasting the traditional PID control system the design in this paper significantly improves the temperature control accuracy of electric vehicle gloves, with less overshoot and stronger robustness. It is great significance to improve the reliability of the real-time temperature control system in different environments and the comfortable sensation of wearing for electric vehicle glove.

There are two common phases of silicon nitride, low temperature phase α and high temperature phase β. It is irreversibly transformed into β phase in a single direction when α phase is in high temperature, α phase and β phase can be transformed into other phases of silicon nitride under certain conditions. In this paper, a crystal model of silicon nitride is established based on the CASTEP module of Materials Studio. The interaction between ion core and valence electron is described by using norm-conserving pseudoptential, structural optimization and calculation of β-Si3N4 are performed. The cut-off energy, k-points and other parameters were set by convergence test. Charge-enrichment, electron transfer and gain-loss electrons of β-Si3N4 were analyzed through simulation, the band structure of β-Si3N4 which has been established was calculated. Research results show that the structure of β-Si3N4 is an indirect bandgap semiconductor, and s orbital and p orbital electrons of Si and N in β-Si3N4 directly affect the peak value of the total density of states.

The generating heat from bearings and a motor of a built-in high rotating speed spindle of a machine tool has to be dissipated to attain high machining accuracy. In this study, a machine tool with a coolant cooling system for a high rotating speed spindle was investigated. The cooling channel designs in terms of channel pattern and dimensions by the design of experiment method (DOE) on the cooling effect of the spindle were studied. By the optimized cooling channel design, the cooling efficiency can be improved by 57.6% and the generating temperature in the spindle can be reduced by 25.9°C.

Background Preoperative conditions may play a significant role in postoperative cognitive dysfunction (POCD) development in elderly patients. We aimed to investigate whether preoperative cognitive training could lower the incidence of POCD one week after surgery. Material/Methods A total of 141 ASA I–III elderly patients who underwent gastrointestinal surgery were enrolled into the study. Patients were randomized into either the Intervention group (69 analyzed) or the Control group (72 analyzed). Patients in the intervention group were instructed and trained in a cognition mnemonic skill for a total of three 1-hour sessions with the method of loci (MoL). Controls did not receive any cognitive training during hospitalization. All patients were tested using neuropsychological battery tests (NPTs) on admission and one week after surgery. Result The incidence of POCD in the intervention group (15.9%) was significantly lower than in the controls (36.1%) (P

In the Radio Frequency Identification (RFID) system, the information of tags will collision when there are several tags in the identification process of readers. This paper first introduces the basic principle of collision, and then it mainly analyzes the respective characteristics of time division multiple access (TDMA) and code division multiple access (CDMA). At the same time it introduces the ALOHA algorithm basic on TDMA. On the basis of them this paper puts forward the improved spread slotted ALOHA anti-collision algorithm. This algorithm not only combine with the principle of TDMA and CDMA, but also it use packet retransmission mechanism when tag collision occurs. It means that it groups the tags when the tags collision still occurs, they will be retransmit in the following time slot. It can be seen from the simulation results, the improved algorithm can effectively enhance the throughput and it reduce delay performance of the system.

Dense heterogeneous cellular networks (HCNs) with energy harvesting nodes are promising solutions to meet both the capacity and energy efficiency needs in the next generation cellular networks. This paper studies the system performance of both energy harvesting and information receiving in a K-tier cellular networks with time-switching simultaneous wireless information and power transfer (SWIPT). Based on stochastic geometry theory, we derive the closed-form formulas for the average harvested energy, the average transmission rate and the total power and information gains. Moreover, we propose a scheme that can optimally adjust the bias factors of tier selection while leveraging the system between energy harvesting and information receiving.

CMOS-compatible 100 V / 650 V enhancement-mode high electron mobility transistors (E-HEMTs) and 650 V depletion-mode MISFET (D-MISFET) are fabricated on 6-inch GaN-on-Si wafers. These devices show excellent power converter switching performances. Both 100 V and 650 V E-HEMTs had passed industrial reliability qualifications. The importance of bulk leakage, interface quality and gate trapping in dynamic on-resistance is figured out. The device with optimized processes shows a significant reduction of the dynamic on-resistance degradation.

A new method for fabricating double fiber Bragg gratings at the same location on a fiber is described. Two series of refractive index change in a fiber, not similar to the normal fiber grating, have been realized by a Fresnel prism interferometer. As a result, the transmission spectrum of the fiber grating is widened, which is attributed to the chirp of the grating. If the exposure condition is controlled properly, then there are two obvious loss peaks in the transmission spectrum observed, which shows that the double fiber Bragg gratings exist in the fiber core. At the same time, a potential application—simultaneous measurement of strain and temperature using this kind of gratings—is analyzed.

A successful direct, etching system excited by a vacuum ultraviolet hollow-cathode lamp is reported. The result shows that the facility can transfer a mesh pattern exactly and directly to n-type GaAs wafer, which is the same as that direct, etched by synchrotron radiation.

The article established a Matlab simulation model of Ni-MH battery based on Zimmerman equivalent circuit model according to the actual charging and discharging characteristics of Ni-MH battery. The simulation analysis shows that the model can not only represent the charging and discharging dynamics characteristics of the Ni-MH battery exactly, but also reflect some factors' influence such as temperature, charging and discharging rates. The simulation analysis shows that the model can not only accounts for charging and discharging dynamics characteristics of the Ni-MH battery, but also effects of some factors such as temperature, charging and discharging rates. Besides, the article obtained the relationship between simulation parameters and the initial battery terminal voltage through mathematical derivation. It provided the conditions for the realistic simulation of charging and discharging characteristics of Ni-MH battery. The Matlab simulation model proposed in this paper can achieve fast simulation and has high value and broad application prospects for simulation of energy systems with battery.

A new method for handwritten digits recognition based on hidden markov model (HMM) and particle swarm optimization (PSO) is proposed. This method defined 24 strokes with the sense of directional, to make up for the shortage that is sensitive in choice of stating point in traditional methods, but also reduce the ambiguity caused by shakes. Make use of excellent global convergence of PSO; improving the probability of finding the optimum and avoiding local infinitesimal obviously. Experimental results demonstrate that compared with the traditional methods, the proposed method can make most of the recognition rate of handwritten digits improved.

The noise in the radar data results in the flutter of the flight target in display screen, which may disturb observer. A rounding method for radar target track using Butterworth filter is proposed in this paper. With the spectrum characteristics of radar target track being analyzed, the filter’s parameters can be designed and figured out. Therefore, after the noise in radar signal is magnified by a transformation algorithm, it can be smoothed online. The results of MATLAB illustration show that the method has a reliable denoising performance.

In aggregate relation, there are semantic propagations between whole object and part object because the whole object manages and controls the part object. So, based on the lifetime of object, semantic propagations of creating and destroying operation between whole object and part object are clarified in the paper. On the other hand, semantic propagations of the other operations in aggregate relation are also discussed. However, UML only represents aggregate and composition without representing the semantic propagations in aggregate relation. In order to describe real world clearly and correctly, UML is extended for theirs visual expression and theirs formalization in algebraic theory is presented.

The use of the electro-optic effect in crystalline quartz to form a passive optical fiber voltage sensor is described. The underlying principle and the temperature characteristics of the probe and modal noise of the fibers are discussed. Some modifications are mentioned. The selection of a broad spectral bandwidth source and a multimode fiber with large core can reduce the modal noise. A prism with a suitable kind of glass material is designed which can improve the temperature characteristic. The experimental results show that the measurement stability of the optical fiber voltage sensor is better than 1%. >

The experiment results of FFPI with the fineness more than 100 at center wavelenth 0.63um and throughput of 40-50 percent have been achieved.The relations of fineness N and peak transmissonT to coupling loss g and mirror reflecticity R are descussed here.

The degradation in fiber strength and the change of fiber refractive index during fusion splicing are observed through mechanical optical experiments and microanalysis. A hydrofluoric acid solution effectively enhances some performances after fusion occurs. A novel transmitted-light differential interference contrast (DIC) system is used to nondestructively measure the refractive index profile (RIP) of an optical fiber.