We report a bubbling chemical vapor deposition method for mass production of high-quality graphite nanosheets using molten copper as the catalyst continuous growth. Bubbles containing precursor gas (CH4 or natural gas) are produced by inserting an aerator into copper. High-quality with thickness ranging from few to 40 graphitic layers grown on bubble surfaces and carried surface. The rate can be high 9.4 g/h crucible volume 3 L. quality is demonstrated composites very conductivity. highly...

The synthesis of enantiomerically pure 3-aryl substituted indanones is developed using an enantioselective sulfoxide-based Knoevenagel condensation/Nazarov cyclization procedure. After the reductive desulfonation methyl para-tolyl sulfoxide-containing chiral auxiliary under mild conditions, selected indanone used for divergent total syntheses three resveratrol natural products (+)-isopaucifloral F, (+)-quadrangularin A, and (+)-pallidol.

The low temperature coefficient and high linearity of the input-output characteristics are both required for high-performance microelectromechanical systems (MEMS) capacitive accelerometers. In this work, a structural designing bulk MEMS accelerometer is developed linearity. Firstly, contrary effect wide-narrow gaps ratio (WNGR) on scale factor (TCSF) error discussed. Secondly, ability an improved structure that can avoid illustrated. proposed in our previous work reducing bias (TCB) TCSF....

This paper investigates how the orientation of applied demagnetizing magnetomotive force (MMF) affects demagnetization behavior Nd-Fe-B magnets that are widely used for permanent-magnet synchronous machines (PMSMs). designs and builds a customized test fixture can produce magnetic field with varying intensity to demagnetize magnet samples. A computer-controlled 2-D mapping device is record flux density above The measurement results compared 3-D finite-element analysis simulations....

This article discusses a high-speed brushless doubly-fed machine (BDFM) for aviation turboelectric distributed propulsion application. After brief overview of the fundamentals and architecture, electromagnetic properties newly designed BDFM are analyzed. An innovative rotor mechanical design is introduced, which allows significant increase speed compared to legacy designs. Experiments were conducted verify 12 000-r/min operation. The findings in this will give prominence feasibility applying...

Lithium-ion batteries (LIBs) have the lead as most used power source for electric vehicles and grid storage systems, a battery thermal management system (BTMS) can ensure efficient safe operation of lithium-ion batteries. Epoxy resin board (ERB) offers wide range applications in LIBs due to its significant advantages such high dielectric strength, electrical insulation, good mechanical stiffness. This study proposes an air-cooled module comprised sixteen prismatic incorporating ERB layer...

We introduce a generalized, efficient, and accurate power abstraction model generation techniques for complex IP blocks. This is based on the contributor modeling concept, which exploits nature of consuming components in design being inherently separable. The generated Process, Voltage Temperature (PVT) independent, thus enabling very efficient hierarchical analysis. Our approach constitutes industry's first methodology to automatically generate PVT independent abstracts. also describe...

A compact broadband monopole tapered slot antenna (MTSA) for vehicle electromagnetic compatibility tests in the semianechoic chambers (SAC) is proposed and investigated. The MTSA takes metal ground of SAC as part an antenna. With mirroring effect plate SAC, acts a conventional (TSA) but with only half size TSA, also avoids adverse reflections on field uniformity effectively. Moreover, has its flaring that reduces weight by 30%. Both simulated measured results show achieves standing wave...

摘要: 在实际工况下,旋转矢量(Rotate vector,RV)减速器的振动信号往往掺杂噪声。被噪声污染后的振动信号给RV减速器的故障诊断带来挑战。为此,提出一种噪声干扰下的卷积神经网络模型(Anti-noise network,ANNet)以实现RV减速器的故障模式识别。该模型首先将一维振动信号通过信号堆叠的方式转化成二维灰度图像,然后采用Dropout操作直接对原始输入信号进行随机干扰,并同时利用多个不同尺度的卷积核对输入信号的不同特征进行自动提取和融合。进一步将ANNet算法与其他算法进行了对比分析,结果表明在不同强度的噪声干扰下,ANNet算法相比于其他算法具有更强的抗噪干扰能力;尤其是在强噪干扰环境下,ANNet模型的诊断准确率比现有算法高出10%~20%。最后探讨和解释了模型的特殊结构设计以及模型具备抗噪能力的原因。

This article investigates the time-dependent demagnetization behavior of NdFeB permanent magnets used for electrified vehicles. A mathematical model magnetic viscosity was derived using maximum-likelihood estimation based on test data. then to predict magnet over time. fixture and a programmable dc power supply were apply constant demagnetizing field N48H samples. hall-effect sensor online measurement under wide time range. buck converter generate pulsed in timescale milliseconds. The...

In this paper, a compact, band-notched ultra-wideband (UWB) fully-recessed antenna with pattern diversity is proposed and demonstrated for vehicle-to-X communications. The composed of multi-port central radiator fully embedded inside bowl-shaped ground structure flush top. consists top circular plate, four split-quarter conical monopoles, vertically-and horizontally-orientated strips, metallic cylinder, bottom cylinder. Moreover, F-shaped monopoles are loaded to the producing two narrow...

This paper experimentally investigates temperature-dependent demagnetization of Nd-Fe-B magnets used in high power density permanent magnet synchronous machines (PMSMs) for electric vehicles. BH curves simulated using first-order, second-order and optimal temperature coefficients were compared with measured curves. A control system was built to the temperature. Two N48H samples demagnetized by a test fixture under various combinations field intensity. Simulation results coefficient...

This paper investigates how the orientation of applied demagnetizing magnetomotive force (MMF) affects demagnetization behavior Nd-Fe-B magnets that are widely used for permanent magnet synchronous machines (PMSMs). work designs and builds a customized test fixture can produce magnetic field with varying intensity to demagnetize samples. A computer-controlled 2D mapping device is record flux density above The measurement results compared 3D finite element analysis (FEA) simulations....

The hybrid modular multilevel converter (MMC) consisting of half-bridge submodules (HBSMs) and full-bridge (FBSMs) is a promising solution for overhead lines high-voltage direct current systems (HVDC) due to the advantages short circuit fault ride-through (DC-FRT) capability. This paper proposes an improved phase-disposition pulse width modulation (PDPWM) method converter. number carriers can be reduced from 3N (N in each arm) 6. theoretical harmonic analysis PDPWM MMC performed by using...

The existing concept of aviation turboelectric distributed propulsion for passenger aircraft relies on direct current (DC) power transmission and distribution. mass efficiency performance DC-based systems becomes challenging as the system rating increases. This work proposes a based brushless doubly-fed machines, which will minimize conversion, enhance mechanical reliability, strengthen fault-tolerance capability. paper presents background proposed along with modeling, control algorithm...

With the development of communication technology, increasing scale power network is bigger and bigger. Based on important significance electric to establish an alarm information acquisition system necessary. CORBA, as a distributed processing environment interconnect solutions in hardware software, widely used field management for its high versatility. In this paper we use real-time CORBA platform TAO develop kind system.

Doubly-fed induction machines (DFIMs) have been widely used in wind power generation and high drives. The brushless versions further improve the reliability reduce maintenance cost by eliminating brushes slip rings, showing great potential replacing traditional DFIMs. successful model-based control development of doubly-fed relies heavily on fidelity plant model, which most existing DFIM models lack. This paper proposes a generalized high-fidelity modeling approach extracting lookup tables...

Grid-forming control technology can make power system have active support ability, so it has broad application prospect in new system. In this paper, the main grid-forming techniques are systematically introduced and their characteristics compared. Then, advantages disadvantages of different converters for The strategy high voltage cascaded energy storage is introduced, pointed out that topology natural use control. This paper also points although equipment suitable development systems, will...