This article has carried on the simulation research of tool wear in electrical discharge machining (EDM) small holes titanium alloy with finite element method. Aiming at electrode material removal process EDM, a 3D thermodynamics model single pulse is established Ansys software. By simulating Gaussian distribution heat flux and thermal convection loads channel, same type surface source exerted both positive negative electrodes different coefficients characteristics, to analyze temperature...

The wind resource has the intermittence characteristic, and electricity quantity of a farm is determined by local resource. In practice, it difficult to compare economic operation situations farms in different conditions. Evaluation indicators for are discussed according actual monitoring farms. high/low frequency ride through farms, low voltage turbines, SVC/SVG dynamic response characteristics ability active power control used evaluation on Then consistency processing, dimensionless...

Objective To evaluate the feasibility of using an intrarectal Foley catheter during ultrasound-guided high-intensity focused ultrasound (US-HIFU) in patients with benign uterine diseases posterior wall beyond HIFU therapeutic range.Methods Patients were treated US-HIFU and lesion changes monitored contrast-enhanced MRI from June 2020 to September 2021. A was inserted into rectum facilitate a successful ablation. Complications responses recorded treatment follow-up.Results Thirteen 14 lesions...

Bridgewire of a thin resistive wire widely used in electric explosive devices (EED) as transducer electronic energy to thermal provide the ignition energetic compounds. In this paper temperature variation laws bridgewire core component and most sensitive part for EED under constant current were investigated though infrared measuring system. The result indicates that thermodynamic equilibrium from was realized two senconds maximum caused by rises quadratic parabola with increasing acting on...

Achromatic phase matching (APM), a favorable method in increasing bandwidth, is explored for second harmonic generation of ultrashort pulses based on typical grating telescope system. A set coupled equations incorporating angular dispersion constructed the space–time domain. An analytic solution with pump tilting pulsed Gaussian beam to given under undepleted approximation. With aid matrix formalism, some properties conversion are demonstrated. Though maximal bandwidth obtained, makes active...

When the system reaches static voltage stability limit point, Jacobian matrix is singular. By checking if minimum singular value zero, its very easy to determine whether or not So of can reflects degree effectively. Firstly this paper introduces decomposition, analyses load characteristic and excitation limits involved in method examples on PSD-FDS are demonstrated. At last, suggestion monitoring by proposed.

This paper took the intensive receiving-end power grid as research object and analysed problems of three-phase short-circuit current over-limited 500kV in early stage UHV construction. Firstly, this influence factors based on self-impedance analysis model two-port network theory equivalent grid. Then, applicable current-limiting measures were put forward. Finally, proposed one scheme to solve buses practical verified feasibility from three different aspects. Aiming at influential factors,...

We present the design and characterization of a three-dimension metamaterial consisted Jerusalem cross unit cell on each side cube lattice substrate for terahertz frequencies. The retrieved effective medium parameters from scattering data prove that has negative permeability permittivity in wide frequencies range 1.47-1.73 THz. demonstrate can be regarded as polarization insensitive absorber with an absorptivity 46% at 1.49 Such designed materials may find numerous applications ranging...

Lanzhou-Xinjiang passenger dedicated line is the first high speed railway on chinas northwestern Gobi where temperature range large and wind huge. Most road section of Lan-Xin subgrade. This paper researches ballastless track subgrade settlement observation scheme assessment method area climatic conditions harsh geologic complex. The result shows that: accuracy tests satisfies requirement by using Layered instrument, intelligent static force level high-accuracy Hydraulic instrument; Subgrade...

The temperature of electric initiating device under constant current has the vital significance to security and firing performance electrical explosive initiator. In this paper, bridgewire semiconductor bridge which were representative in devices (EED) was studied using infrared microscopic thermographer. curve with change is obtained. resluts indicate that increases form quadratic parabola rises slower than bridgewire. According experimental analysis, it found reason attributed better heat...

In this paper, the problem of excessive generator tripping value security and stability control after occurrence N-2 fault in Shentou-Yantong transmission line Shanxi DaTong Regional grid is studied. And principle measures based on equal area criterion analyzed. The reason leading to generator-tripping region figured out, it that steady-state limit section decreases accelerator power cannot be released. Finally, results theoretical analysis are verified by simulations. simulation indicate...

A phenomenon that the damping ratio will decrease when power flows from both sides to primary grid is summarized and analyzed in paper. Based on analysis of change West Inner Mongolia-Shandong oscillation under sequential operation mode hedge mode, a three-machine equivalent system established study edge (ETE) operating system. The influence magnitudes trends flow analyzed, reason why ratios decreases send mid-side explained.

Both the voltage critical clearing time (VCCT) and transient transmission capacity (VTTC) are always used to evaluate stability of system voltage, their relationships studied clarified in paper. The is mainly depended on dynamic reactive characteristics load power. Based analysis a power network, VCCT VTTC this Finally, conclusion, i.e. margin has nonlinear characteristic, obtained by simulations actual grid. According cannot be exactly reflected margin.

if the power system is disturbed by a large disturbance, its damping characteristics would change due to nonlinear factor during dynamic process and redistribution of flow after accident operation mode. In this paper, impact mode an for disturbance stability grid are studied respectively. And then, simulation comparison, it concludes that parts automatic regulating devices have little on suffers mainly determined under accident. Finally, conclusions verified through practical North China...

To implement the multi-directional test of WAMS application system, and to satisfy requirement for flexibility reusability platform system is designed built. Firstly, basic functions, components software structure are described. Then, realization data model multi-source interface other aspects expounded in detail. Finally, by using developed completely, case aiming at disturbance source location based on produced, work finished. The results verify accuracy practicability system. Moreover, it...

Engine is carried the test on thermal balance and drag in vehicle working condition to analysis distribution of energy from combustion. The heat coolant that combustion flow into cooling system different temperature not same. results show engine comes ranging minimum at 3000-4000r/min, effective power output accounts for total up 25% full load reaching maximum. Based data, it established control module can be controlled by speed, torque power, when ECU reads signal forecast target conditions...

In order to determine the most unfavorable condition of steel box girder, ensure its stress and deformation in safe state, girder bridge should apply finite element analysis software modeling analysis. At same time, data calculation can provide theoretical evidence for factory manufacturing lines. The tender DB01 continuous Hong Kong-Zhuhai-Macao Bridge provides backdrop this essay, using MIDAS/Civil 2012 do numeral simulation on hoisting, then analyzing main beam at different construction...

For increasingly complex often appear in the low frequency oscillation of interconnected power grid, rapid positioning disturbance source to ensure processing accident, reduce accident influence has become especially important, therefore national grid project related study proposes a decomposition method and moment based on cut set energy partition layer position theory, success ground demonstration construction location system WAMS data sources; Disturbance localization algorithm, this...

We present a design and systematic numerical study of an amorphous Si/metal plasmonic solar cell structure for the total ratio light trapping at visible frequencies. The proposed consists periodic metallic grating arrays on side semiconductor active layer cell. 3.48 can be achieved, which attributes to localized surface plasmon generated from enhancing absorption in region. influence geometry parameters conductor material has been also investigated. results used practical device design.

Regional energy base with large installed capacity, small local power load capacity and great amount of transmission have been more common in China. For this kind sending end grid, the 3rd line defense for frequency stability is crucial. The high generator tripping an effective emergency control measure. But its setting configuration mainly relies on operational experience off-line simulation calculation. An equivalent model suitable analysis calculation introduced firstly. Based model,...

Wireless Sensor Networks is a novel technology of information acquisition and processing. It integrates the technologies sensor, wireless communication, microelectronics. can sense collect environmental parameters in range network, then process cooperatively real time. We discuss design principle performance evaluation method data fusion algorithm for sensor networks detail. introduce concept cost, emphasize that must be combined with specific application background. Finally, we proposed...

High-energy proton beams have extensive and important applications. Traditional accelerators are bulky costly. The high-power laser pulse technology provides a new acceleration scheme based on the interaction between plasma, has advantage of miniaturization. Furthermore, comparing with traditional accelerators, gradient by pulses can be increased three orders magnitude. high brightness, narrow width, good directionality generated in theory within very small effective size, they suitable for...