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91.
针对车间作业的加工受到机床、操作工人等双资源制约条件下出现多种扰动的JSP调度问题,提出了基于受控Petri网和GASA对不同扰动进行分类处理的新方法。首先通过构建带有控制器的Petri网模型使系统的运行满足期望的目标,然后基于该模型把遗传算法和模拟退火算法相结合,以最小化最大完工时间为目标,基于机床故障修复时间、工人离岗时间及取消订单包含任务的多少进行分类调度,然后根据扰动恢复后剩余任务的多少决定是否进行再次调度,避免大范围调整造成的生产不稳定状态,最大限度的维持车间的生产能力。最后通过实例验证了算法的有效性和可行性。 相似文献
92.
93.
制造过程资源消耗和环境影响分析模型及应用 总被引:5,自引:0,他引:5
制造过程的资源消耗和环境影响可以看成是一系列加工工艺单元资源消耗和环境排放的组合.利用IPO(input-process-output)图建立了一种包括制造过程工艺链及其输入输出关系的框架模型,提出了一种进行加工工艺资源消耗和环境影响之间关联性分析的方法,在此基础上,建立了一种集成各加工工艺输入和输出的制造过程资源消耗和环境影响分析模型.该模型能够对制造过程输入资源和输出环境影响之间的关系进行描述,为通过资源消耗减量化来降低环境排放提供技术支持.结合某阀体的制造过程进行了应用,验证了上述方法和模型的有效性和可行性. 相似文献
94.
95.
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer’s optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties. This research is partially supported by the National Natural Science Foundation of China under Grant Nos. 60674082, 70221001, and 70731003. 相似文献
96.
In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is of order O(h^2), one order higher than its interpolation error when the exact solution belongs to H^3(Ω). However, the interpolation error and consistency error of Carey element are of order O(h). It seems that the above special property has never been seen for other triangular elements for the second order problems. 相似文献
97.
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer's optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties. 相似文献
98.
针对一类不确定奇异系统,研究其Terminal滑模控制问题。通过非奇异线性变换把不确定奇异系统变换成受限等价形式,利用Lyapunov函数方法,首次提出了一种新的Terminal滑模控制策略,给出了特殊的Terminal滑模超曲面,设计了相应的滑模控制器,实现了滑模运动,保证了系统状态变量在有限时间内收敛到平衡点。给出数值算例,说明了方法的有效性。 相似文献
99.
针对部队航电组件测试任务繁重、故障定位率低的问题,提出一种利用历史数据来简化测试任务、提高故障定位率的方法。利用粗糙集信息系统理论,建立了航电组件故障信息系统模型;基于测试任务辨识函数和诊断允许误差对测试任务进行约简;基于最短测试时间选出最优测试任务集;利用贝叶斯最大后验概率进行故障诊断推理,将诊断问题归结为不等式约束极值问题;用0-1规划隐数算法求得最优解。最后以某型飞机惯导部件为例验证了方法的快速有效性。 相似文献
100.
瞬态极化新体制雷达,通过单脉冲获得瞬时极化散射矩阵来提取目标特征信息,提高了雷达系统在复杂电磁环境中的探测、抗干扰和反隐身等方面能力。基于该雷达工作原理,提出“同时正交双极化”的射频前端设计方案,完成了国内首部瞬态极化雷达试验系统射频前端的研发。采用正交双通道和幅相一致性技术保证了雷达实现瞬态极化的功能,采用滤波技术保证了射频系统的频谱纯度;采用低噪声放大技术有效降低了接收机噪声系数;采用直接频率综合技术提高了射频系统频率稳定度和相参性能;结构集成一体化设计保证了射频收发前端的电磁兼容性能和便携性。射频前端测试结果均优于指标要求,并支持试验系统初步解决了目标极化散射特征提取与识别领域的基础性和共性难题。 相似文献