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91.
Meng Yu Tsai Ko Chun Lee Che Yi Lin Yuan Ming Chang Kenji Watanabe Takashi Taniguchi Ching Hwa Ho Chen Hsin Lien Po Wen Chiu Yen Fu Lin 《Advanced functional materials》2021,31(40):2105345
In bionic technology, it has become an innovative process imitating the functionality and structuralism of human biological systems to exploit advanced artificial intelligent machines. Bionics plays a significant role in environmental protection, especially for its low energy loss. By fusing the concept of receptor-like sensing component and synapse-like memory, the photoactive electro-controlled optical sensory memory (PE-SM) is proposed and realized in a single device, which endows a simple methodology of reducing power consumption by photoactive electro-control. The PE-SM is the system built with the stacked atomically thick materials, in which rhenium diselenide serves as a robust photosensor, hexagonal boron nitride serves as a tunneling dielectric, and graphene serves as a charge-storage layer. With the features of the PE-SM, it performs synaptic metaplasticities under optical spikes. In addition, a simulated spiking neural network composed of 24 × 24 PE-SMs is further presented in an unsupervised machine learning environment, performing image recognition via the Hebbian rule. The PE-SM not only improves the neuromorphic computing efficiency but also simplifies the circuit-size structure. Eventually, the concept of photoactive electro-control can extend to other photosensitive 2D materials and provide a new approach of constructing either visual perception memory or photonic synaptic devices. 相似文献
92.
针对高等学校多业务信息系统资源整合的情况,该文基于Novell Nsure Identity Manager 3技术,建立了统一身份库,设计了数据同步机制,整合了与学生密切相关的教务系统、研究生管理系统、学费管理系统、助学货款系统、奖学金管理系统和图书馆管理系统的相关数据,建立了学生信息综合服务平台,实现了学生缴费、缓... 相似文献
93.
On the performance of random vector quantization limited feedback beamforming in a MISO system 总被引:8,自引:0,他引:8
In multiple antenna wireless systems, beamforming is a simple technique for guarding against the negative effects of fading. Unfortunately, beamforming requires the transmitter to have knowledge of the forward-link channel which is often not available a priori. One way of overcoming this problem is to design the beamforming vector using a limited number of feedback bits sent from the receiver to the transmitter. In limited feedback beamforming, the beamforming vector is restricted to lie in a codebook that is known to both the transmitter and receiver. Random vector quantization (RVQ) is a simple approach to codebook design that generates the vectors independently from a uniform distribution on the complex unit sphere. This correspondence presents performance analysis results for RVQ limited feedback beamforming 相似文献
94.
Andy Hon Wai Chun Rebecca Y. M. Wong 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2007,37(2):268-277
The ability to maximize service quality while minimizing cost is very important to service-oriented businesses, such as lorry leasing. Very often, the ability to consistently offer higher quality service is the main differentiating factor between a business and its competitors. For lorry leasing businesses, service quality and cost are directly related to how resources-vehicles, cranes, and drivers-are allocated to jobs. The ability to assign the right combination of resources is crucial to daily operations. This paper presents how we modeled this assignment problem as a constraint-satisfaction problem (CSP) and implemented using constraint programming (CP) with an algorithm that we call the crane-lorry optimizing engine (CLOE). CLOE was implemented for the largest crane-lorry company in Hong Kong. Furthermore, plans are generated within seconds compared to close to an hour if done manually. All necessary constraints and criteria are considered systematically. We have experimented with many different types of search heuristics and have analyzed their effects on plan quality. We have found that by considering both the experience of the crane-lorry-driver combination and maximizing on the order assignment, we were able to generate plans that were significantly better than those produced by human planners, and within a substantially shorter time. Although the use of constraint-based assignment techniques is still limited in the vehicle leasing industry, we hope our combination of automated assignment with Internet portal technology that streamlines business-to-business, business-to-consumer, and business-to-employee communications can excite interest in this area 相似文献
95.
寻呼信道不仅能够传送系统的寻呼消息,而且还能够传输系统消息并进行鉴权登记等,因此寻呼信道的性能对整个网络性能指标的提高起了极其重要的作用。文中针对寻呼信道中通用寻呼消息,开销消息,短消息等随着话务量的变化对寻呼信道容量产生的影响做出了分析,并进一步提出了优化意见。 相似文献
96.
疏编织漏泄同轴电缆空间场分布的研究 总被引:1,自引:0,他引:1
通过对SLYWV-75-10型疏编织漏泄同轴电缆的空间场分布进行实际测量,并对测试结果和数据进行分析,证明SLYWV-75-10型疏编织漏泄同轴电缆完全能够作为户外周界入侵探测报警系统的探测传感器,同时对电缆间距、最大单元警戒范围以及系统的响应时间等给出了具体的参考指标,对户外周界入侵探测报警系统的研制和开发具有重要指导意义. 相似文献
97.
发射天线罩抗微波烧毁理论分析 总被引:1,自引:0,他引:1
杜建春 《电子信息对抗技术》2002,17(2):17-22
本文给出了机载宽带大功率发射天线抗烧毁理论分析方法和实验结果 ,从天线近场理论出发 ,计算了天线罩、极化器、密封膜片等处的功率密度。结合材料特性 ,给出了天线罩等的安全距离的计算公式 ,并提出了具体的抗微波烧毁措施。 相似文献
98.
连续40 W 808 nm量子阱线阵二极管激光封装技术 总被引:4,自引:4,他引:4
研究了高功率二极管激光 (LD)封装中的铟焊料蒸镀工艺和回流焊工艺对芯片焊接状态的影响。在数值模拟和实验研究的基础上 ,优化了冷却器结构设计 ,研制出具有热阻低、压降小的铜微通道液体冷却器 ,可以满足热耗散功率大于 6 0W的二极管激光器散热冷却需要。通过封装实验得到输出功率 40W ,波长 80 8nm ,谱线半高宽<2nm ,电光效率近 40 %的连续线阵二极管激光器。用该激光器进行了抽运Nd∶YAG固体激光实验 ,在抽运功率为 40W时 ,获得 11 8W单横模固体激光输出 ,光 光效率约为 30 %。 相似文献
99.
100.
针对近红外场景仿真中需要将不同材质分类的问题,提出一种谱聚类的灰度纹理图像分割方法.首先利用mean-shift算法,将原始图像预分割为多个具有准确边界的同质区域,并将这些区域描述为超像素;进而,将超像素构造的无向加权图作为谱聚类的输入,通过谱聚类的方法解决超像素的过分割问题.本文的方法在谱聚类过程中考虑了超像素的纹理特征,弥补了灰度图像在谱聚类过程中只顾及灰度和空间信息的不足.实验结果表明,利用本文分割方法不但减少了运算量,并且为精细的近红外场景仿真奠定了基础. 相似文献