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41.
In this article, we focus on the question of why some bachelor's students have more proficiency in ICT skills and use computers and the Internet more frequently than other students do. To answer this question, we rely on the core variables of the TAM (Technology Acceptance Model), on the orientation of students toward scientific research, and on contextual factors. TAM has been applied successfully in research before, but in this article, the model is expanded with variables regarding the orientation of students toward scientific research, and is geared towards the relationship to basic ICT skills and the sustained use of these skills. In order to attain a more reliable instrument to measure proficiency in ICT skills and the frequency of ICT use, several new instruments are constructed. The results show that this model, a combination of four basic TAM variables, together with the identity commitment of students focused on the appreciation of scientific research and some context variables, can explain a substantial proportion of the variance in different ICT skills, but considerably less of the frequency of ICT use. 相似文献
42.
The relationship between exposure to sexually objectifying music television, primetime television programs, fashion magazines, and social networking sites and the internalization of beauty ideals, self‐objectification, and body surveillance was examined among adolescent girls (N = 558). A structural equation model showed direct relationships between sexually objectifying media and the internalization of beauty ideals, and indirect relationships between sexually objectifying media and self‐objectification, and body surveillance through the internalization of beauty ideals. The direct relationships between sexually objectifying media and the internalization of beauty ideals, self‐objectification, and body surveillance differed across the types of sexually objectifying media. The discussion focuses on the implications of these findings to explain self‐objectification among girls. 相似文献
43.
One of the major drawbacks of the classical Lotka function is that arguments only start from the value 1. However, in many
applications one may want to start from the value 0, e.g. when including zero received citations. In this article we consider
the shifted Lotka function, which includes the case of zero items. Basic results for the total number of sources, the total
number of items and the average number of items per source are given in this framework. Next we give the rank-frequency function
(Zipf-type function) corresponding to the shifted Lotka function and prove their exact relation. The article ends with a practical
example which can be fitted by a shifted Lotka function. 相似文献
44.
Integer Programming (IP) has been used to model educational timetabling problems since the very early days of Operations Research. It is well recognized that these IP models in general are hard to solve, and this area of research is dominated by heuristic solution approaches. In this paper a Two-Stage Decomposition of an IP model for a practical case of high school timetabling is shown. This particular timetabling problem consists of assigning lectures to both a timeslot and a classroom, which is modeled using a very large amount of binary variables. The decomposition splits this model into two separate problems (Stage I and Stage II) with far less variables. These two separate problems are solved in sequence, such that the solution for the Stage I model is given as input to the Stage II model, implying that irreversible decisions are made in Stage I. However, the objective of the Stage II model is partly incorporated in the Stage I model by exploiting that Stage II can be seen as a minimum weight maximum matching problem in a bipartite graph. This theoretically strengthens the decomposition in terms of global optimality. The approach relies on Hall's theorem for the existence of matchings in bipartite graphs, which in its basic form yields an exponential amount of constraints in the Stage I model. However, it is shown that only a small subset of these constraints is needed, making the decomposition tractable in practice for IP solvers. To evaluate the decomposition, 100 real-life problem instances from the database of the high school ERP system Lectio are used. Computational results show that the decomposition performs significantly better than solving the original IP, in terms of both found solutions and bounds. 相似文献
45.
46.
《Microelectronics Journal》2014,45(8):1118-1124
A novel nanoelectronic single-electron content addressable memory is designed and simulated. The proposed memory has three important building blocks: a storage block, a comparison block and an addressing block. These building blocks were built based on single-electron circuits such as Reset-Set latches, exclusive-or gates and a WTA neural network. Each one of the building blocks was separately adjusted to provide room temperature operation before being connected together. Some analyses concerning stability of each block and of the whole memory circuit were made. The nanoelectronic memory was successfully validated by simulation. 相似文献
47.
《Journal of the European Ceramic Society》2014,34(10):2453-2463
Different factors such as the way of incorporating the Y2O3 stabilizer, alumina addition and sintering temperature were assessed with the goal to improve the low temperature degradation (LTD) resistance of 3Y-TZP without compromising on the mechanical properties. The degradation of hydrothermally treated specimens was studied by X-ray diffraction, micro-Raman spectroscopy and scanning electron microscopy.Decreasing the sintering temperature decreased the LTD susceptibility of 3Y-TZPs but did not allow to obtain a LTD resistant 3Y-TZP with optimized mechanical properties. Alumina addition along with the use of Y2O3 stabilizer coated starting powder allowed to combine both an excellent toughness and LTD resistance, as compared to alumina-free and stabilizer co-precipitated powder based equivalents. Transmission electron microscopy revealed that the improved LTD resistance could be attributed to the segregation of Al3+ at the grain boundary and the heterogeneously distributed Y3+ stabilizer. 相似文献
48.
Considering that demand for healthcare services is constantly increasing, outpatient services must improve their performance. Being able to satisfy the demand with a limited outpatient service capacity is an important operational challenge. The objective of our research consists in studying the relationships and interactions between patient flows, resource capacity (number of consulting rooms and number of nurses) and appointment scheduling rules in order to improve an outpatient orthopaedic clinic performance. Discrete event simulation is used to model outpatient flows. An experimental design was developed to test how to assign consulting rooms and nurses to each orthopedist considering four appointment scheduling rules and three patient flow types of varied complexity. Analysis of variance and the Tukey test are used to evaluate the simulation results. Our conclusion is that in order to improve the outpatient orthopaedic clinic performance, resources (consulting rooms, nurses) and appointment scheduling rules must be adapted to the different patient flows. 相似文献
49.
This article examines the popular claim of Content Management Systems (CMSs) that providing a rich toolset and leaving the use under learner control is beneficial to learning. By means of a literature review, the current contribution examines whether all students are capable of using CMS tools so that their learning is enhanced. In contrast to what is assumed, the study conceptualizes tool use as a complex self-regulation strategy that cannot be taken for granted. Specifically, the article reviews empirical studies in relation to three topics: (a) personal agency in tool use, (b) performance effects of tool use and (c) influencing tool use variables. Findings reveal that not every student profited from the CMS learning opportunities; in multiple studies students differed in their tool use, and these differences had significant performance effects. Hence, these findings suggest that the pedagogical claim CMSs make is problematic. Besides this accumulated corpus of knowledge, the review revealed serious limitations in the retrieved studies which could hamper our findings. As a consequence, the review establishes a need for further research into students’ CMS tool use from an instructional design perspective. In addition to the theoretical framework, several directions for future research are given. 相似文献
50.
The Aristotelian square of oppositions is a well-known diagram in logic and linguistics. In recent years, several extensions of the square have been discovered. However, these extensions have failed to become as widely known as the square. In this paper we argue that there is indeed a fundamental difference between the square and its extensions, viz., a difference in informativity. To do this, we distinguish between concrete Aristotelian diagrams (such as the square) and, on a more abstract level, the Aristotelian geometry (a set of logical relations). We then introduce two new logical geometries (and their corresponding diagrams), and develop a formal, well-motivated account of their informativity. This enables us to show that the square is strictly more informative than many of the more complex diagrams. 相似文献