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21.
随着信息化步伐的加快,网电空间正在不断加深对人类社会的影响。网电空间的重要作用已经得到世界各国的广泛认同。网电空间战将成为未来战争的重要部分。本文分析了网电空间的定义和重要性,介绍了网电空间战的威力,研究了美国网电空间战能力建设中的重要举措,指出我国加强网电空间战能力建设的必要性。  相似文献   
22.
任务驱动教学法是建立在建构主义学习理论基础上的教学模式,将知识的学习放置于具体问题解决上来,通过学生自身或小组协作,来完成任务.在学习计算机编程的课程时,使用任务驱动法教学,可以大大提高教学效果,同时又能培养一种良好的团队精神,体现以学生的全面发展为中心的教育思想.  相似文献   
23.
On Controllability of Switched Linear Systems   总被引:1,自引:0,他引:1  
This paper investigates the number of switchings and design of switching sequences for controllability of switched linear systems. Two related results are established. One is a new constructive approach to designing switching sequences. The controllable state set of each switching sequence designed via the approach coincides with the controllable subspace of switched linear systems. The other is a well-estimated value for the minimum number of switchings required for controllability. Each state in the controllable subspace can be steered to origin within this value of switching times.  相似文献   
24.
Segmenting human faces automatically is very important for face recognition and verification, security system, and computer vision. In this paper, we present an accurate segmentation system for cutting human faces out from video sequences in real-time. First, a learning based face detector is developed to rapidly find human faces. To speed up the detection process, a face rejection cascade is constructed to remove most of negative samples while retaining all the face samples. Then, we develop a coarse-to-fine segmentation approach to extract the faces based on a min-cut optimization. Finally, a new matting algorithm is proposed to estimate the alpha-matte based on an adaptive trimap generation method. Experimental results demonstrate the effectiveness and robustness of our proposed method that can compete with the well-known interactive methods in real-time.  相似文献   
25.
We built and tested one of the key components of a free-space holographically interconnected stored-program optoelectronic computer: a counter. The counter is constructed with 1-ns-latency optoelectronic NOR gates and is interconnected with holographic optical elements. Two synchronization methods were also demonstrated: the gate-and-strobe method and the time-of-flight method. These counters represent prototypical optoelectronic finite-state controllers. They were developed to demonstrate the feasibility of providing optoelectronic controllers for optoelectronic processors.  相似文献   
26.
Radiotherapy is identified as a crucial treatment for patients with glioblastoma, but recurrence is inevitable. The efficacy of radiotherapy is severely hampered partially due to the tumor evolution. Growing evidence suggests that proneural glioma stem cells can acquire mesenchymal features coupled with increased radioresistance. Thus, a better understanding of mechanisms underlying tumor subclonal evolution may develop new strategies. Herein, data highlighting a positive correlation between the accumulation of macrophage in the glioblastoma microenvironment after irradiation and mesenchymal transdifferentiation in glioblastoma are presented. Mechanistically, elevated production of inflammatory cytokines released by macrophages promotes mesenchymal transition in an NF-κB-dependent manner. Hence, rationally designed macrophage membrane-coated porous mesoporous silica nanoparticles (MMNs) in which therapeutic anti-NF-κB peptides are loaded for enhancing radiotherapy of glioblastoma are constructed. The combination of MMNs and fractionated irradiation results in the blockage of tumor evolution and therapy resistance in glioblastoma-bearing mice. Intriguingly, the macrophage invasion across the blood-brain barrier is inhibited competitively by MMNs, suggesting that these nanoparticles can fundamentally halt the evolution of radioresistant clones. Taken together, the biomimetic MMNs represent a promising strategy that prevents mesenchymal transition and improves therapeutic response to irradiation as well as overall survival in patients with glioblastoma.  相似文献   
27.
Ji  Naye  Zhang  Fan  Zhang  Haoxiang  Zhao  Youbing  Yu  Dingguo 《Virtual Reality》2023,27(2):887-901
Virtual Reality - Mixed reality applications often require virtual objects that are partly occluded by real objects. However, previous research and commercial products have limitations in terms of...  相似文献   
28.
Qian  Li Ping  Han  Shuai  Ji  Bo  Zhang  Yan 《Mobile Networks and Applications》2022,27(3):1081-1083
Mobile Networks and Applications -  相似文献   
29.
Chen  Lizhe  Wu  Ji  Yang  Haiyan  Zhang  Kui 《Software Quality Journal》2022,30(3):757-779
Software Quality Journal - Regression testing is required in each development iteration of microservice systems. Test case prioritization, which improves the fault detection rate by optimizing the...  相似文献   
30.
Liu  Zixian  Du  Guansan  Zhou  Shuai  Lu  Haifeng  Ji  Han 《Computational Economics》2022,59(4):1481-1499
Computational Economics - The study aims to analyze and forecast Internet financial risks based on the model based on deep learning and the Back Propagation Neural Network (BPNN). First, the theory...  相似文献   
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