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31.
Popular media describe adverse effects of helicopter parents who provide intense support to grown children, but few studies have examined implications of such intense support. Grown children (N = 592, M age = 23.82 years, 53% female, 35% members of racial/ethnic minority groups) and their parents (N = 399, M age = 50.67 years, 52% female; 34% members of racial/ethnic minority groups) reported on the support they exchanged with one another. Intense support involved parents' providing several types of support (e.g., financial, advice, emotional) many times a week. Parents and grown children who engaged in such frequent support viewed it as nonnormative (i.e., too much support), but grown children who received intense support reported better psychological adjustment and life satisfaction than grown children who did not receive intense support. Parents who perceived their grown children as needing too much support reported poorer life satisfaction. The discussion focuses on generational differences in the implications of intense parental involvement during young adulthood.  相似文献   
32.
We studied the inferences of an availability system with reboot delay and standby switching failures in which the system consisted of two operating units and one warm standby. The system was studied under the assumption that the time-to-failure and the time-to-repair were assumed to follow an exponential and a general distribution. The reboot times are assumed to be exponentially distributed with parameter β. We constructed a consistent and asymptotically normal estimator of availability for such a repairable system. Based on this estimator, interval estimation and testing hypothesis were developed by using logit transformation. To implement the simulation inference for the system availability, we adopted two repair-time distributions—namely, lognormal and Weibull; and three types of Weibull distributions—characterized by their shape parameters—were considered. Finally, appropriate tables and figures of all simulation results have been included.  相似文献   
33.
Few studies have focused on the different roles risk factors play in the multistate temporal natural course of breast cancer. We proposed a three‐state Markov regression model to predict the risk from free of breast cancer (FBC) to the preclinical screen‐detectable phase (PCDP) and from the PCDP to the clinical phase (CP). We searched the initiators and promoters affecting onset and subsequent progression of breast tumor to build up a three‐state temporal natural history model with state‐dependent genetic and environmental covariates. This risk assessment model was applied to a 1 million Taiwanese women cohort. The proposed model was verified by external validation with another independent data set. We identified three kinds of initiators, including the BRCA gene, seven single nucleotides polymorphism, and breast density. ER, Ki‐67, and HER‐2 were found as promoters. Body mass index and age at first pregnancy both played a role. Among women carrying the BRCA gene, the 10‐year predicted risk for the transition from FBC to CP was 25.83%, 20.31%, and 13.84% for the high‐, intermediate‐, and low‐risk group, respectively. The corresponding figures were 1.55%, 1.22%, and 0.76% among noncarriers. The mean sojourn time of staying at the PCDP ranged from 0.82 years for the highest risk group to 6.21 years for the lowest group. The lack of statistical significance for external validation () revealed the adequacy of our proposed model. The three‐state model with state‐dependent covariates of initiators and promoters was proposed for achieving individually tailored screening and also for personalized clinical surveillance of early breast cancer.  相似文献   
34.
High quality handwritten numeral recognition is currently seen as an essential capability in the area of office automation. Statistical algorithms applied to this task can have a very significant impact because they offer the possibility of generalizing the information contained in a training set to new examples, without requiring an extensive programming effort tailored to specific hand-written styles. In this thesis, we apply the deformable probabilistic template approach to a problem of recognizing handwritten digits. Unlike previous published works in this area, the template is fed directly with images, rather than feature vectors, thus demonstrating the ability of Bayesian models to deal with large amounts of global and high-level information.  相似文献   
35.
产权安排对风险资本的发展致关重要。日本风险资本的典型特征便是产权缺失。产权的缺失使日本风险资本处于另类均衡状态,其直接的结果就是导致风险资本投资偏离正确的轨道,投资效率低下。  相似文献   
36.
Multivariate Capability Indices: Distributional and Inferential Properties   总被引:1,自引:0,他引:1  
Process capability indices have been widely used in the manufacturing industry for measuring process reproduction capability according to manufacturing specifications. Properties of the univariate processes have been investigated extensively, but are comparatively neglected for multivariate processes where multiple dependent characteristics are involved in quality measurement. In this paper, we consider two commonly used multivariate capability indices MCp and MCpm, to evaluate multivariate process capability. We investigate the statistical properties of the estimated MCp and obtain the lower confidence bound for MCp. We also consider testing MCp, and provide critical values for testing if a multivariate process meets the preset capability requirement. In addition, an approximate confidence interval for MCpm is derived. A simulation study is conducted to ascertain the accuracy of the approximation. Three examples are presented to illustrate the applicability of the obtained results.  相似文献   
37.
In this paper, the phenomenon of the optimal management of requests of service in general networks is formulated as a control problem for a finite number of multiserver loss queues with Markovian routing. This type of problem may arise in a wide range of fields, e.g., manufacturing industries, storage facilities, computer networks, and communication systems. Using inductive approach of dynamic programming, the optimal admission control can be induced to be the functions of the number of requested service in progress. However, for large-scale network, the computational burden to find optimal control policy may be infeasible due to its involvement of the states for all stations in the networks. Hence, the idea of bottleneck modeling is borrowed to compute the near-optimal admission control policy. We reduced the scale of loss network and decreased the difference between the original and reduced models by making compensation for system parameters. A novel method is proposed in this paper to compute the compensation. Numerical results show that the near-optimal control policy demonstrates close performance to the optimal policy.  相似文献   
38.
陶弘景集注古代药学知识的意义,在中国本草学的发展历程上,乃是承先启后;在医疗史的研究范畴里,则是反映相关知识在特定时空背景下的变革。中世以下的批评者们,大多着眼于知识本体的正误,他们虽然推崇陶弘景在文本体例上的贡献,但却对陶注的内容多所抨击,认为其有悖博物宗旨。不过,换个角度来看,陶氏的注文,其实正适足以反映历史变迁,对医学与医疗所产生的影响。在这个视野之下,陶注本身就是一种因应外在环境变动而产生的知识集成。因为半壁江山,影响的不止是政治、经济、社会与文化,还包括了药学的体质,以及药学中有关药物基原与产地的信息重整。  相似文献   
39.
Process capability indices are widely used to evaluate the performance of processes in the manufacturing industry. Over the years, the issues have been investigated extensively. Some articles have studied them with fuzzy estimation. However, it seems that no article has proposed a version of triangular fuzzy numbers for critical value to test the process capability. In this article, we use Buckley's approach (2003 Buckley , J. J. ( 2003 ). Fuzzy Probabilities: New Approach and Application . Heidelberg : Physica-Verlag .[Crossref] [Google Scholar]) to construct the triangular fuzzy numbers for C pl and C pu , especially, the triangular fuzzy numbers for critical values are derived to execute the fuzzy hypothesis testing for C pl and C pu . Some numerical examples are taken to illustrate the proposed methodology.  相似文献   
40.
The group ranking problem involves constructing coherent aggregated results from users’ preference data. The goal of most group ranking problems is to generate an ordered list of all items that represents the user consensus. There are, however, two weaknesses to this approach. First, a complete list of ranked items is always output even when there is no consensus or only a slight consensus. Second, due to similarity of performance, in many practical situations, it is very difficult to differentiate whether one item is really better than another within a set. These weaknesses have motivated us to apply the clustering concept to the group ranking problem, to output an ordered list of segments containing a set of similarly preferred items, called consensus ordered segments. The advantages of our approach are that (i) the list of segments is based on the users’ consensuses, (ii) the items with similar preferences are grouped together in the same segment, and (iii) the relationships between items can be easily seen. An algorithm is developed to construct the consensus of the ordered segments from the users’ total ranking data. Finally, the experimental results indicate that the proposed method is computationally efficient, and can effectively identify consensus ordered segments.  相似文献   
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