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121.
ABSTRACT

This article presents a critical policy historiography of how Early School Leaving has been understood as a social problem and what policy responses have been enacted to tackle it in the Italian context, devoting a specific attention to the analysis of the translation of EU policy ideas, tools and recipes to reduce ESL. It shows how the formulation of a global and integrated national strategy to tackle ESL in Italy in 2018 can be interpreted as the result of a troubled process of re-culturing. Such a reculturing is the effect of the complex interplay between the legacies of the Italian welfare regime in education and the co-option of the ESL issue within a EU political frame that struggles to combine economic rationalism and social justice. Such a struggle is interpreted as contributing to a profound rethinking of education and its mission.  相似文献   
122.
Handwriting is a complex activity that involves continuous interaction between lowerlevel perceptual-motor and higher-level cognitive processes. All handwriting models describe involvement of executive functions (EF) in handwriting development. Particular EF domains associated with handwriting include maintenance of information in working memory, inhibition of prepotent responses, and shifting and sustaining of attention. Generativity, an EF domain that has not been extensively studied, may play a role in the acquisition and automation of handwriting. We hypothesized that neuropsychological performances and handwriting fluency would be mutually associated, and that visuospatial generativity could have a specific role in handwriting speed. We enrolled 96 children who completed a comprehensive neuropsychological battery. The study found that handwriting speed was associated with visuospatial fluency, which involves behavioural execution and initiation. In learning and performing handwriting, there is an inherent non-exclusive role of fine motor skills.  相似文献   
123.

Objective

The reliability of child witness testimony in sexual abuse cases is often controversial, and few tools are available. Criteria-Based Content Analysis (CBCA) is a widely used instrument for evaluating psychological credibility in cases of suspected child sexual abuse. Only few studies have evaluated CBCA scores in children suspected of being sexually abused. We designed this study to investigate the reliability of CBCA in discriminating allegations of child sexual abuse during court hearings, by comparing CBCA results with the court's final, unappealable sentence. We then investigated whether CBCA scores correlated with age, and whether some criteria were better than others in distinguishing cases of confirmed and unconfirmed abuse.

Methods

From a pool of 487 child sexual abuse cases, confirmed and unconfirmed cases were selected using various criteria including child IQ ≥ 70, agreement between the final trial outcome and the opinion of 3 experts, presence of at least 1 independent validating informative component in cases of confirmed abuse, and absence of suggestive questions during the child's testimonies. This screening yielded a study sample of 60 confirmed and 49 unconfirmed cases. The 14 item version of CBCA was applied to child witness testimony by 2 expert raters.

Results

Of the 14 criteria tested, 12 achieved satisfactory inter-rater agreement (Maxwell's Random Error). Analyses of covariance, with case group (confirmed vs. unconfirmed) and gender as independent variables and age as a covariate, showed no main effect of gender. Analyses of the interaction showed that the simple effects of abuse were significant in both sex. Nine CBCA criteria were satisfied more often among confirmed than unconfirmed cases; seven criteria increased with age.

Conclusion

CBCA scores distinguish between confirmed and unconfirmed cases. The criteria that distinguish best between the 2 groups are Quantity of Details, Interactions, and Subjective Experience. CBCA scores correlate positively with age, and independently from abuse; all the criteria test except 2 (Unusual Details and Misunderstood Details) increase with age. The agreement rate could be increased by merging criteria Unusual and Superfluous details that achieve a low inter-rater agreement when investigated separately.

Practice implication

Given its ability to distinguish between confirmed and unconfirmed cases of suspected child abuse, the CBCA could be a useful tool for expert opinion. Because our strict selection criteria make it difficult to generalize our results, further studies should investigate whether the CBCA is equally useful in the cases we excluded from our study (for example mental retardation).  相似文献   
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126.
The growing interest in the conservation of historic buildings encourages the development of water-repellent materials and methodologies to consolidate and/or protect stones. Recently, particular attention was devoted to composites of inorganic oxides nanoparticles and hybrid siloxane or silicone polymers. Here we present a study on the water repellence of a thin protective coating obtained through sol-gel process starting from Glymo and Dynasylan 40®, and loading the silicate matrix with nano-sized silica particles (Aeroxide LE1® -Degussa-Evonik). The coatings were applied to limestone, sandstone and granite samples. The silica nanoparticles have been characterized by XRD, the siloxane matrix through micro-Raman spectroscopy, while the surface morphology was examined by SEM. The efficacy of the treatments has been evaluated through static contact angle measurements and capillary water absorption. The optical appearance of the coatings was evaluated by colorimetric measurements. Nanoparticles at suitable concentration gave high values for the static contact angle (up to ∼ 150°), for all stone species even for four months exposure to atmospheric conditions. The coatings, in the water capillary absorption tests, however, behave as expected only for granite even if the long-term water direct contact reduces the hydrophobicity.  相似文献   
127.
More than 20 years ago, electrical impedance spectroscopy (EIS) was proposed as a potential characterization method for flow cytometry. As the setup is comparably simple and the method is label-free, EIS has attracted considerable interest from the research community as a potential alternative to standard optical methods, such as fluorescence-activated cell sorting (FACS). However, until today, FACS remains by and large the laboratory standard with highly developed capabilities and broad use in research and clinical settings. Nevertheless, can EIS still provide a complement or alternative to FACS in specific applications? In this Perspective, we will give an overview of the current state of the art of EIS in terms of technologies and capabilities. We will then describe recent advances in EIS-based flow cytometry, compare the performance to that of FACS methods, and discuss potential prospects of EIS in flow cytometry.  相似文献   
128.
This work presents the development of an array of bioreactors where finely controlled stirring is provided at the microliter scale (100–300 μl). The microliter-bioreactor array is useful for performing protocol optimization in up to 96 parallel experiments of hematopoietic stem cell (HSC) cultures. Exploring a wide range of experimental conditions at the microliter scale minimizes cost and labor. Once the cell culture protocol is optimized, it can be applied to large-scale bioreactors for stem cell production at the clinical level. The controlled stirring inside the wells of a standard 96-well plate is provided by buoyancy-driven thermoconvection. The temperature and velocity fields within the culture volume are determined with numerical simulations. The numerical results are verified with experimental velocity measurements using microparticle image velocimetry (μPIV) and are used to define feasible experimental conditions for stem cell cultures. To test the bioreactor array’s functionality, human umbilical cord blood-derived CD34+ cells were cultured for 7 days at five different stirring conditions (0.24–0.58 μm∕s) in six repeated experiments. Cells were characterized in terms of proliferation, and flow cytometry measurements of viability and CD34 expression. The microliter-bioreactor array demonstrates its ability to support HSC cultures under stirred conditions without adversely affecting the cell behavior. Because of the highly controlled operative conditions, it can be used to explore culture conditions where the mass transport of endogenous and exogenous growth factors is selectively enhanced, and cell suspension provided. While the bioreactor array was developed for culturing HSCs, its application can be extended to other cell types.  相似文献   
129.
This work deals with state synchronization of heterogeneous linear agents with unknown dynamics. The problem is solved by formulating the synchronization problem as a special model reference adaptive control where each agent tries to converge to the model defined by its neighbors. For those agents that do not know the reference signal that drives the flock, a fictitious reference is estimated in place of the actual one: the estimation of such reference is distributed and requires measurements from neighbors. By using a matching condition assumption, which is imposed so that the agents can converge to the same behavior, the fictitious reference estimation leads to adaptive laws for the feedback and the coupling gains arising from distributed matching conditions. In addition, the coupling connection is not scalar as in most literature, but possibly vector-valued. The proposed approach is applicable to heterogeneous agents with arbitrarily large matched uncertainties. A Lyapunov-based approach is derived to show analytically asymptotic convergence of the synchronization error: robustification in the presence of bounded errors or unknown (constant) leader input is also discussed. Finally, a motivational example is presented in the context of Cooperative Adaptive Cruise Control and numerical examples are provided to demonstrate the effectiveness of the proposed method.  相似文献   
130.
This paper studies the problem of composite synchronization and learning of multiple coordinated robot manipulators subject to heterogeneous nonlinear uncertain dynamics under the leader-follower framework. A new two-layer distributed adaptive learning control scheme is proposed, which consists of the first-layer distributed cooperative estimator and the second-layer decentralized deterministic learning controller. The first layer aims to enable each robotic agent to estimate the leader’s information. The second layer is responsible for not only controlling each individual robotic agent to track over desired reference trajectory, but also accurately identifying/learning each robot’s nonlinear uncertain dynamics. Design and implementation of this two-layer distributed controller can be carried out in a fully-distributed manner, which do not require any global information including global connectivity of the communication network. The Lyapunov method is applied to rigorously analyze stability and parameter convergence of the resulting closed-loop system. Numerical simulations on a team of two-degree-of-freedom robot manipulators have been conducted to demonstrate the effectiveness of the proposed results.  相似文献   
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