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12.
500kV顺德站VQC软件实用化将大大减轻运行人员的工作量,为500kV顺德站以后实现无人值班提供的技术保障。本文对顺德站VQC软件使用进行需求调研以及实用化的过程详细介绍。对500kV变电站VQC软件使用的可行性、技术要求、现场测试、改进措施等进行了介绍,为500kV变电站VQC软件推广应用提供了借鉴及应用经验。  相似文献   
13.
Dual-material gate (DMG) field effect transistor   总被引:5,自引:0,他引:5  
A generic new type of field effect transistor (FET), the dual material gate (DMG) FET, is proposed and demonstrated. The gate of the DMGFET consists of two laterally contacting materials with different work functions. This novel gate structure takes advantage of material work function difference in such a way that the threshold voltage near the source is more positive than that near the drain (for n-channel FET, the opposite for p-channel FET), resulting in a more rapid acceleration of charge carriers in the channel and a screening effect to suppress short-channel effects. Using the heterostructure FET as a vehicle, the principle, computer simulation results, design guidelines, processing, and characterization of the DMGFET are discussed in detail  相似文献   
14.
为了了解ENIG化学变化对浸金耐蚀性的形响,探讨了浸金电镀溶液的pH值和化学性质与结果所得到的浸金层的耐蚀性之间的关系。  相似文献   
15.
We report on the role of cesium fluoride (CsF) doping on the enhanced electron transport properties of tris-(8-hydroxyquinolin) aluminum (Alq3) for organic light-emitting diodes. The electronic structures of CsF-doped Alq3 layers with various doping concentration are characterized by in situ ultraviolet and X-ray photoelectron spectroscopies, showing an n-type electrical doping effect with Fermi level shift towards unoccupied molecular orbital and the formation of chemistry-induced gap-states. The increase in conductivity and reduction in electron injection barrier in CsF-doped Alq3 layer with optimal doping concentration lead to the enhanced electron injection and transport, which are consistent with the improved electrical characteristics of OLEDs.  相似文献   
16.
The Space-Air-Ground Integrated Network(SAGIN) realizes the integration of space, air,and ground networks, obtaining the global communication coverage.Software-Defined Networking(SDN) architecture in SAGIN has become a promising solution to guarantee the Quality of Service(QoS).However, the current routing algorithms mainly focus on the QoS of the service, rarely considering the security requirement of flow. To realize the secure transmission of flows in SAGIN, we propose an intelligent flow forwarding scheme with endogenous security based on Mimic Defense(ESMD-Flow). In this scheme, SDN controller will evaluate the reliability of nodes and links, isolate malicious nodes based on the reliability evaluation value, and adapt multipath routing strategy to ensure that flows are always forwarded along the most reliable multiple paths. In addition, in order to meet the security requirement of flows, we introduce the programming data plane to design a multiprotocol forwarding strategy for realizing the multiprotocol dynamic forwarding of flows. ESMD-Flow can reduce the network attack surface and improve the secure transmission capability of flows by implementing multipath routing and multi-protocol hybrid forwarding mechanism. The extensive simulations demonstrate that ESMD-Flow can significantly improve the average path reliability for routing and increase the difficulty of network eavesdropping while improving the network throughput and reducing the average packet delay.  相似文献   
17.
Ge-nanoclusters were formed by electron-beam irradiation in Ge-doped silica-on-silicon thin films. The size and density of the clusters can be controlled by the irradiation intensity and time.  相似文献   
18.
Modality-independent elastography (MIE) is a method of elastography that reconstructs the elastic properties of tissue using images acquired under different loading conditions and a biomechanical model. Boundary conditions are a critical input to the algorithm and are often determined by time-consuming point correspondence methods requiring manual user input. This study presents a novel method of automatically generating boundary conditions by nonrigidly registering two image sets with a demons diffusion-based registration algorithm. The use of this method was successfully performed in silico using magnetic resonance and X-ray-computed tomography image data with known boundary conditions. These preliminary results produced boundary conditions with an accuracy of up to 80% compared to the known conditions. Demons-based boundary conditions were utilized within a 3-D MIE reconstruction to determine an elasticity contrast ratio between tumor and normal tissue. Two phantom experiments were then conducted to further test the accuracy of the demons boundary conditions and the MIE reconstruction arising from the use of these conditions. Preliminary results show a reasonable characterization of the material properties on this first attempt and a significant improvement in the automation level and viability of the method.  相似文献   
19.
A new Frequency-Hopping (FH) signal detection method is proposed. Different from previous methods which need to monitor the total band, it can monitor part of the band and decrease the range of the bandwidth. According to this method, a new detection model is set and the computation formulas of the detection probability and false-alarm probability are given. The parameters of a VHF radio are used to prove the validity of the method. Simulation results show that this method can decrease the range of the bandwidth and detect the FH signal with some penalty on the SNR and signal loss.  相似文献   
20.
基于移动支付的自动售货机   总被引:3,自引:1,他引:3  
主要介绍一种采用SIEMENS MC35模块实现移动支付功能的自动售货机设计方案。文中简要说明了MC35模块、移动支付流程及MDB总线;设计了一种基于MC35模块的自动售货机结构,并给出总线转换接口的软硬件实现思路。  相似文献   
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