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201.
This article analyzes a class of stochastic contests among multiple players under risk‐averse exponential utility. In these contests, players compete over the completion of a task by simultaneously deciding on their investment, which determines how fast they complete the task. The completion time of the task for each player is assumed to be an exponentially distributed random variable with rate linear in the player's investment and the completion times of different players are assumed to be stochastically independent. The player that completes the task first earns a prize whereas the remaining players earn nothing. The article establishes a one‐to‐one correspondence between the Nash equilibrium of this contest with respect to risk‐averse exponential utilities and the nonnegative solution of a nonlinear equation. Using the properties of the latter, it proves the existence and the uniqueness of the Nash equilibrium, and provides an efficient method to compute it. It exploits the resulting representation of the equilibrium investments to determine the effects of risk aversion and the differences between the outcome of the Nash equilibrium and that of a centralized version.© 2016 Wiley Periodicals, Inc. Naval Research Logistics 66:4–14, 2019  相似文献   
202.
针对资源受限情形下的两阶段攻防资源分配问题,提出一种基于多属性决策的资源分配对策模型。防守者首先将有限的防护资源分配到不同的目标上,继而进攻者选择一种威胁组合方式对目标实施打击。基于博弈论相关知识,模型的求解结果可以使防守者最小化自身损失,使进攻者最大化进攻收益。同时,针对模型的特点,给出了一些推论和证明。通过一个示例验证了模型的合理性以及相关推论的准确性,能够为攻、防双方规划决策提供辅助支持。  相似文献   
203.
States employ extended deterrence to shield third parties from aggression. The concept is traditionally applied to interstate relations, collective security arrangements, and strategic considerations. The protective relationship that exists between a state sponsor of terrorism and its non-state militant proxy is rarely considered. This article will introduce and explore the sponsor–proxy relationship in the context of extended deterrence, and relate it to Iran’s support and sponsorship of political violence, militancy, and terrorism in Europe. The article reviews the rationale states have for sponsoring terrorism, and illustrates the promises and pitfalls associated with extending deterrence to non-state militants.  相似文献   
204.
This article argues that the nuclear nonproliferation norm (NNPN) is a social fact with a relatively independent life of its own and that it has a powerful impact on the behavior of both nuclear-weapon states (NWS) and non-nuclear-weapon states (NNWS). It challenges the application of critical constructivist research on norms to the NNPN and the idea that its legitimacy and structural power depend on contestation “all the way down.” State and non-state actors play an important role in explaining the dynamics of the NNPN, but agential constructivism runs the danger of “throwing the baby out with the bath water,” neglecting the structural impact of the NNPN on state behavior. The article examines the limitations of norm-contestation theory, arguing that some norms are more resistant to contestation than others. The NNPN is more difficult to contest than new norms (such as the Responsibility to Protect) because it is rooted in fifty years of nonproliferation nuclear diplomacy. The US-India nuclear deal is not a case of “norm change” but a violation of the NNPN. The “core” of the NNPN has not changed since the US-India nuclear deal. The conflict confronting NWS and NNWS is about the implementation of “type 2” norms (organizing principles) and “type 3” norms (standardized procedures), and not about the “hard core” of the NNPN.  相似文献   
205.
本文证明了二部图存在(g,f)匹配和f 因子的充要条件以及有关的几个结果,并且给出了求二部图的最大(g,f)匹配、最小(g,f)匹配和最小权最大f 匹配、最小权(g,f)匹配、最大权(g,f)匹配的算法。  相似文献   
206.
将马尔可夫判决过程和智能强化学习算法相结合,给出了异构无线网络环境下用户业务偏好评估模型的技术框架。为动态环境下用户需求的感知、量化和适配特征的研究提供了基本的数学描述,对解决用户体验的评价问题和业务与业务环境的适配问题提供了新的研究思路。仿真结果表明所构建的MDP模型能够在多状态条件下学习用户偏好,根据用户需求智能选择业务。  相似文献   
207.
针对不确定环境下无人机区域搜索问题,建立了实时探测更新的搜索方法,提出了机载光电载荷参数优化配置策略。建立了基于二维离散网格的无人机区域搜索模型,采用概率地图描述目标信息的实时获取与更新;引入不确定度指标、目标网格的重访和网格探测次数控制,建立搜索目标函数;建立了基于粒子群算法的搜索路径滚动优化方法;通过对任务区域平均探测时间步数和误判概率的估计分析,建立了机载光电载荷参数优化配置策略。使用蒙特卡洛方法验证了区域搜索方法的有效性和光电载荷参数配置对搜索效率、误判概率的影响。  相似文献   
208.
《防务技术》2020,16(4):825-833
The combination of 5,5′-bistetrazole-1,1′-diolate (TKX-50) and ammonium perchlorate (AP) can make greater use of the chemical energy of TKX-50 based energetic materials. The research on the interaction mechanism between TKX-50 and AP is very important for designing TKX-50-AP compounds and judging the formation feasibility of composite particles, which can lay a theoretical foundation for the preparation of TKX-50-AP mixed crystals and the application of TKX-50 in propellant, propellant and explosive. Herein, in order to research the interaction mechanism between TKX-50 and AP, density-functional theory calculation was applied to optimize three configurations of TKX-50-AP compounds. The geometry structure, electrostatic potential and binding energy of the compounds were predicted, and the electronic density topological analysis was also carried out. Then TKX-50-AP mixed crystals structures were constructed, and the radial distribution function of H–O and H–N in mixed crystals was calculated. Finally, solvent/non-solvent method was applied to prepare TKX-50-AP composites, and the infrared spectroscopy and the non-isothermal decomposition performance of the composites were characterized. Results show that the superposition of positive charges in TKX-50 molecule and negative charges in AP makes the electrostatic potential distributions of TKX-50-AP compounds different from that of TKX-50 and AP. The interaction energies of TKX-50-AP 1, TKX-50-AP 2 and TKX-50-AP 3 are 39.743 kJ/mol, 61.206 kJ/mol and 27.702 kJ/mol, respectively. The interaction between TKX-50 molecules and AP molecules in TKX-50-AP mixed crystals both depends on hydrogen bonds and van der Waals force, and the number and strength of hydrogen bonds are significantly greater than that of van der Waals force. The composition of AP and TKX-50 makes the absorption peak of the five-membered rings and NH3OH+ of TKX-50 shift to low wavenumber in the infrared spectroscopy. In general, TKX-50 interacts with AP via hydrogen bonds and van der Waals force, and the calculated results are in good agreement with the experimental results. The composition of TKX-50 and AP can also prolong the decomposition process.  相似文献   
209.
科学社会主义理论是一个开放的体系,具有与时俱进的理论品质。中国改革开放的伟大实践有力推动了科学社会主义理论的发展,社会主义事业将不断发展,科学社会主义理论也将得到不断发展。  相似文献   
210.
从分子动理论出发,建立理想气体绝热过程的微观模型,用麦克斯韦速度分布函数导出其过程方程.  相似文献   
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