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901.
本文旨在建立一种现代突厥语的语言内部分类模式.该模式基于共时资料,但像以前的模式,它试图整合历时资料.除语音资料外,这一模式还利用了形态学、词汇学和句法学方面的资料.根据历时和地理因素,对这些特征的分布模式进行了相互比较.由此,我们可以划分出突厥语不同层级的内部语组.而且,这些子语组可以有不同的来源.其中的一些语组是由共同的语言特征维系在一起的,在这个群的语言内部它们似乎具有可从一个时间层面传递到另一个时间层面,并构成他们共同的发生学遗传的语言特征.笔者将这类群称为发生学的(子)分支,如乌古斯语支、克普恰克语语支、布尔加尔突厥语支等.显然,其他突厥语的子语群是由不同分支的语言组成,它们已经形成了新的区域单位,进入区域互动.诸如此类的区域群有西伯利亚突厥语.在文中第二部分,笔者从历史事实和发展的时序关系方面,对发生学分支进入子分支的内部分类过程和区域群的形成及分解过程进行了阐述.  相似文献   
902.
In this study we examine the moderating effect of competitive strategy (including differentiation and cost‐leadership strategies) on the relationship between exploration and firm performance. We find that the moderating effect of differentiation strategy is positive while that of cost‐leadership strategy is negative. And, these moderating effects are stronger in a highly competitive context. This study offers an explanation for previous mixed findings on the linkage of exploration to firm performance and enriches the discipline's knowledge regarding the performance implications of exploration. Moreover, we respond directly to the appeal in research on competitive strategy to clarify the role played by competitive strategy in profiting from exploration.  相似文献   
903.
MapReduce system is a popular big data processing framework, and the performance of it is closely related to the efficiency of the centralized scheduler. In practice, the centralized scheduler often has little information in advance, which means each job may be known only after being released. In this paper, hence, we consider the online MapReduce scheduling problem of minimizing the makespan, where jobs are released over time. Both preemptive and non-preemptive version of the problem are considered. In addition, we assume that reduce tasks cannot be parallelized because they are often complex and hard to be decomposed. For the non-preemptive version, we prove the lower bound is \(\frac{m+m(\Psi (m)-\Psi (k))}{k+m(\Psi (m)-\Psi (k))}\), higher than the basic online machine scheduling problem, where k is the root of the equation \(k=\big \lfloor {\frac{m-k}{1+\Psi (m)-\Psi (k)}+1 }\big \rfloor \) and m is the quantity of machines. Then we devise an \((2-\frac{1}{m})\)-competitive online algorithm called MF-LPT (Map First-Longest Processing Time) based on the LPT. For the preemptive version, we present a 1-competitive algorithm for two machines.  相似文献   
904.
Neighbor sum distinguishing index of 2-degenerate graphs   总被引:1,自引:1,他引:0  
We consider proper edge colorings of a graph G using colors in \(\{1,\ldots ,k\}\). Such a coloring is called neighbor sum distinguishing if for each pair of adjacent vertices u and v, the sum of the colors of the edges incident with u is different from the sum of the colors of the edges incident with v. The smallest value of k in such a coloring of G is denoted by \({\mathrm ndi}_{\Sigma }(G)\). In this paper we show that if G is a 2-degenerate graph without isolated edges, then \({\mathrm ndi}_{\Sigma }(G)\le \max \{\Delta (G)+2,7\}\).  相似文献   
905.
For a given graph and an integer t, the MinMax 2-Clustering problem asks if there exists a modification of a given graph into two maximal disjoint cliques by inserting or deleting edges such that the number of the editing edges incident to each vertex is at most t. It has been shown that the problem can be solved in polynomial time for \(t<n/4\), where n is the number of vertices. In this paper, we design parameterized algorithms for different ranges of t. Let \(k=t-n/4\). We show that the problem is polynomial-time solvable when roughly \(k<\sqrt{n/32}\). When \(k\in o(n)\), we design a randomized and a deterministic algorithm with sub-exponential time parameterized complexity, i.e., the problem is in SUBEPT. We also show that the problem can be solved in \(O({2}^{n/r}\cdot n^2)\) time for \(k<n/12\) and in \(O(n^2\cdot 2^{3n/4+k})\) time for \(n/12\le k< n/4\), where \(r=2+\lfloor (n/4-3k-2)/(2k+1) \rfloor \ge 2\).  相似文献   
906.
The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is known for relatively few classes of graphs, compared to other topological invariants, e.g., genus and crossing number. For the complete bipartite graphs, Beineke et al. (Proc Camb Philos Soc 60:1–5, 1964) gave the answer for most graphs in this family in 1964. In this paper, we derive formulas and bounds for the thickness of some complete k-partite graphs. And some properties for the thickness for the join of two graphs are also obtained.  相似文献   
907.
随着以微博、微信为代表的社交网络信息平台在中国的崛起,形成了新媒体时代下信息资讯生成与扩散的完整传播链条,深刻地影响着金融市场参与主体的学习认知习惯、投资决策理念、交易行为模式,最终影响不同金融资产的价格波动规律. 本文在新媒体时代情景下,以社交网络信息披露与传播平台为切入点,基于信息关注度、信赖度、更新频率等三层维度,构建社交网络微博信息质量指标体系,研究社交网络信息质量与股价同步性的内在关联关系. 研究表明: 微博信息质量与股价同步性有着显著的高度负向线性关联性,并且呈现出非线性 U 型关系. 即随着社交网络信息质量水平的提升,股价同步性逐渐降低到达最小值,而后又逐渐提高. 研究结论为证明上市公司社交网络微博平台对股价同步性有较强影响力,提供了中国金融市场的证据.  相似文献   
908.
本文建立了一个异质性产业体系低碳化发展路径选择的分析框架,通过超越对数形式的随机前沿生产函数,测算了我国29个省区产业体系生产技术及其效率和生产规模效率,以及能源使用技术及其效率和碳减排技术及其效率,并针对不同类型产业体系的低碳化发展提出政策建议.结果表明,我国异质性产业体系可以通过不同的结构升级和技术进步的选择形成适合于自身产业体系特征的低碳化发展路径.  相似文献   
909.
Residual marked empirical process-based tests are commonly used in regression models. However, they suffer from data sparseness in high-dimensional space when there are many covariates. This paper has three purposes. First, we suggest a partial dimension reduction adaptive-to-model testing procedure that can be omnibus against general global alternative models although it fully use the dimension reduction structure under the null hypothesis. This feature is because that the procedure can automatically adapt to the null and alternative models, and thus greatly overcomes the dimensionality problem. Second, to achieve the above goal, we propose a ridge-type eigenvalue ratio estimate to automatically determine the number of linear combinations of the covariates under the null and alternative hypotheses. Third, a Monte-Carlo approximation to the sampling null distribution is suggested. Unlike existing bootstrap approximation methods, this gives an approximation as close to the sampling null distribution as possible by fully utilising the dimension reduction model structure under the null model. Simulation studies and real data analysis are then conducted to illustrate the performance of the new test and compare it with existing tests.  相似文献   
910.
本文选取了1995-2014年全国30个省市数据,综合使用了向量自回归模型、参数面板模型、非参数面板模型和面板门限模型对GDP增速与电力消费增速、第二产业增速、第三产业增速、财政收入增速、货物流转增速、能源消费增速和固定资产投资增速等物理性指标间的关系进行了建模.实证研究发现,GDP增速、电力消费增速、第三产业增速、能源消费增速之间存在作用机制,但是这种影响模式并非一成不变,在不同时间段内,其模式发生改变,同时,这一影响模式也随着人均GDP的变化而发生阶段性改变.在经济新常态下,不能因为经济转型中的GDP数据与物理指数之间发生偏离,而简单否定GDP的准确性.  相似文献   
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