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1.
基于作战环思想, 以作战网络抽象模型为基础, 围绕作战环的分类、定义、形式化描述、数学模型等基本问题开展了理论研究, 进一步丰富了作战环理论体系。同时, 以能否快速有效打击对方目标实体为根本依据, 建立了基于目标节点打击率和基于目标节点打击效率的作战网络效能评估指标。通过仿真实验, 将作战环相关理论运用于不同节点攻击策略下的作战网络效能评估, 为实际作战体系对抗中双方的攻击与防护提供应用指导, 也为进一步开展基于作战环的作战网络应用研究提供参考借鉴。 相似文献
2.
为提高交叉口的机动车通行效率及环境效益,采用改进罚参数来构造一种新的Lagrange乘子法对交叉路口的交通信号进行优化配时。通过权重系数建立车辆延误与尾气排放的数学模型,利用改进Lagrange乘子法进行优化,将其结果与两种典型智能算法的优化结果进行对比,并利用VISSIM(Verkehr in Stadten Simulation)微观交通可视化仿真软件进行验证。实验结果表明,该方法优化的信号配时使车辆延误降低19.89%,尾气排放量降低2.379%,可见大比例优化了交叉口的车辆延误,同时可以降低尾气排放量。 相似文献
3.
C&I(chopping and interleaving)干扰是一种针对线性调频(linear frequency modulation, LFM)雷达的典型干扰样式, 干扰子信号调频斜率与雷达发射信号相同, 利用信号处理工具分离真实回波与干扰信号难度较大。针对该问题, 以LFM相参雷达抗自卫式C&I干扰为背景, 提出基于回波预处理和相参积累的干扰抑制算法。根据估计的回波时延, 设置距离窗截取受干扰回波段, 在此基础上, 通过对回波预处理, 改变不同重复周期内假目标的快时间位置分布, 通过相参积累实现干扰抑制。仿真试验表明, 所提算法能够有效抑制强干扰背景下的C&I干扰, 干扰抑制后真实目标检测概率大幅提高, 虚假目标数量明显减少。 相似文献
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5.
Lei Chen Cong-Fa Huang Yi-Cun Li Wei-Wei Deng Liang Mao Lei Wu Wen-Feng Zhang Lu Zhang Zhi-Jun Sun 《Cellular and molecular life sciences : CMLS》2018,75(11):2045-2058
The NLRP3 inflammasome is a critical innate immune pathway responsible for producing active interleukin (IL)-1β, which is associated with tumor development and immunity. However, the mechanisms regulating the inflammatory microenvironment, tumorigenesis and tumor immunity are unclear. Herein, we show that the NLRP3 inflammasome was over-expressed in human HNSCC tissues and that the IL-1β concentration was increased in the peripheral blood of HNSCC patients. Additionally, elevated NLRP3 inflammasome levels were detected in tumor tissues of Tgfbr1/Pten 2cKO HNSCC mice, and elevated IL-1β levels were detected in the peripheral blood serum, spleen, draining lymph nodes and tumor tissues. Blocking NLRP3 inflammasome activation using MCC950 remarkably reduced IL-1β production in an HNSCC mouse model and reduced the numbers of myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs) and tumor-associated macrophages (TAMs). Moreover, inhibiting NLRP3 inflammasome activation increased the numbers of CD4+ and CD8+ T cells in HNSCC mice. Notably, the numbers of exhausted PD-1+ and Tim3+ T cells were significantly reduced. A human HNSCC tissue microarray showed that NLRP3 inflammasome expression was correlated with the expression of CD8 and CD4, the Treg marker Foxp3, the MDSC markers CD11b and CD33, and the TAM markers CD68 and CD163, PD-1 and Tim3. Overall, our results demonstrate that the NLRP3 inflammasome/IL-1β pathway promotes tumorigenesis in HNSCC and inactivation of this pathway delays tumor growth, accompanied by decreased immunosuppressive cell accumulation and an increased number of effector T cells. Thus, inhibition of the tumor microenvironment through the NLRP3 inflammasome/IL-1β pathway may provide a novel approach for HNSCC therapy. 相似文献
6.
热运动对纳米级磁流变液系统的颗粒团聚行为和宏观流变特性扰动影响不可忽视.为研究施加外磁场后系统微结构与热运动间的关系,探讨在不同颗粒粒径情况下热运动能量在系统总能量中的占比.采用CCD设计方法,分析Monte Carlo仿真获取的颗粒位形信息,生成关于外磁场磁感应强度、颗粒粒径和体积分数的系统热耦合系数<λ>回归模型;成链团聚的临界颗粒粒径计算值比文献经验值高出约23%,证实在考虑系统内多因素的综合影响下,纳米级磁流变液具有更严格的流变现象临界发生条件. 相似文献
7.
几乎Koszul代数作为Koszul代数的推广,在代数周期性和分次自入射代数的研究中起到了重要的作用.几乎Koszul代数的刻画是一个复杂的计算问题,而Loewy矩阵为Koszul代数的刻画带来了较为直观的计算方法.通过经典的Loewy矩阵和构造增广Loewy矩阵,利用分次代数分次模的两种不同Loewy维数向量得到了一个分次模成为d-线性模的充分必要条件,并得到了一个有限维分次代数成为几乎Koszul代数的充分必要条件,从而推广郭晋云利用Loewy矩阵刻画Koszul代数的相关结果. 相似文献
8.
Y.Pazhuhanfar B.Eghbali 《矿物冶金与材料学报》2021,28(6):1080-1089
In the present research, aluminum metal matrix composites were processed by the stir casting technique. The effects of TiB2 rein-forcement particles, severe plastic deformation through accumulative roll bonding (ARB), and aging treatment on the microstructural charac-teristics and mechanical properties were also evaluated. Uniaxial tensile tests and microhardness measurements were conducted, and the micro-structural characteristics were investigated. Notably, the important problems associated with cast samples, including nonuniformity of the rein-forcement particles and high porosity content, were solved through the ARB process. At the initial stage, particle-free zones, as well as particle clusters, were observed on the microstructure of the composite. However, after the ARB process, fracturing phenomena occurred in brittle ceramic particles, followed by breaking down of the fragments into fine particles as the number of rolling cycles increased. Subsequently, com-posites with a uniform distribution of particles were produced. Moreover, the tensile strength and microhardness of the ARB-processed com-posites increased with the increase in the reinforcement mass fraction. However, their ductility exhibited a different trend. With post-deforma-tion aging treatment (T6), the mechanical properties of composites were improved because of the formation of fine Mg2Si precipitates. 相似文献
9.
Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers (TiBw) and titanium diboride particles (TiB2p) were fabricated by powder metallurgy. Microstructural observations showed competitive precipitation behavior between TiBw and TiB2p, where the relative contents of the two reinforcements varied with sintering temperature. Based on thermodynamic and kinetic assessments, the precipitation mechanisms of the hybrid reinforcements were discussed, and the formation of both TiBw and TiB2p from the local melting zone was thermodynamically favored. The precipitation kinetics were mainly controlled by a solid-state diffusion of B atoms. By forming a compact compound layer, in situ reactions were divided into two stages, where Zener growth and Dybkov growth prevailed, respectively. Accordingly, the competitive precipitation behavior was attributed to the transition of the growth model during the reaction process. 相似文献
10.
多智能体深度确定性策略梯度(multi-agent deep deterministic policy gradient, MADDPG)算法是深度强化学习方法在多智能体系统(multi-agent system, MAS)领域的重要运用,为提升算法性能,提出基于并行优先经验回放机制的MADDPG算法。分析算法框架及训练方法,针对算法集中式训练、分布式执行的特点,采用并行方法完成经验回放池数据采样,并在采样过程中引入优先回放机制,实现经验数据并行流动、数据处理模型并行工作、经验数据优先回放。分别在OpenAI多智能体对抗、合作两类典型环境中,从训练轮数、训练时间两个维度对改进算法进行了对比验证,结果表明,并行优先经验回放机制的引入使得算法性能提升明显。 相似文献