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41.
Eduardo Sáenz-de-Cabezón L. Javier HernándezM. Teresa Rivas Esteban García-RuizVicente Marco Ignacio Pérez-MorenoF. Javier Sáenz-de-Cabezón 《Mathematics and computers in simulation》2011,82(1):2-14
This paper presents a new procedure to construct families of spatial approximation-prediction functions which depend on several parameters. The method is based on partitions of the unity. In order to find optimal functions in these families we introduce a Vietoris simplicial set associated to an influence radius. We consider error estimators induced by these Vietoris simplicial sets. A computational implementation of these mathematical models has been developed to be applied to any kind of finite discrete data. Our methods provide a useful tool for the analysis of the spatial distribution of species, which is imperative for developing accurate and efficient management of endangered and invasive species, biological conservation programs, etc. We demonstrate the application of our method to the analysis of the spatial distribution of the grape moth Lobesia botrana (Lepidoptera: Tortricidae) in the vineyards of La Rioja obtaining useful results for the management of this pest. 相似文献
42.
Luis García Esteban Francisco García Fernández Paloma de Palacios 《Computers & Structures》2009,87(21-22):1360-1365
Determining the modulus of elasticity of wood by applying an artificial neural network using the physical properties and non-destructive testing can be a useful method in assessments of the timber structure in old constructions. The modulus of elasticity of Abies pinsapo Boiss. timber was predicted in this study through the parameters of density, width, thickness, moisture content, ultrasonic wave propagation velocity and visual grading of the test pieces. A feedforward multilayer perceptron network was designed for this purpose, achieving 75.0% success in the testing or unknown group. 相似文献
43.
Finite‐time sliding mode observer for uncertain nonlinear systems based on a tunable algebraic solver
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In this paper, a finite‐time sliding mode observer for nonlinear systems with unknown inputs is proposed. The observer is based on a method for the solution of time‐varying algebraic equations. This algebraic solver is shown to converge in finite time by means of Lyapunov analysis; furthermore, a way to tune it so that it converges after a user‐defined amount of time is presented. Through the use of this technique and sliding mode differentiators, the state variables and unknown inputs of a class of nonlinear systems, which do not need to be affine in the inputs, can be estimated without the explicit use of state transformations. Both the algebraic solver and the proposed observer are illustrated through simulation examples. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
44.
Multimodal support to group dynamics 总被引:1,自引:1,他引:0
Fabio Pianesi Massimo Zancanaro Elena Not Chiara Leonardi Vera Falcon Bruno Lepri 《Personal and Ubiquitous Computing》2008,12(3):181-195
The complexity of group dynamics occurring in small group interactions often hinders the performance of teams. The availability
of rich multimodal information about what is going on during the meeting makes it possible to explore the possibility of providing
support to dysfunctional teams from facilitation to training sessions addressing both the individuals and the group as a whole.
A necessary step in this direction is that of capturing and understanding group dynamics. In this paper, we discuss a particular
scenario, in which meeting participants receive multimedia feedback on their relational behaviour, as a first step towards
increasing self-awareness. We describe the background and the motivation for a coding scheme for annotating meeting recordings
partially inspired by the Bales’ Interaction Process Analysis. This coding scheme was aimed at identifying suitable observable
behavioural sequences. The study is complemented with an experimental investigation on the acceptability of such a service.
相似文献
Fabio Pianesi (Corresponding author)Email: |
Massimo ZancanaroEmail: |
Elena NotEmail: |
Chiara LeonardiEmail: |
Vera FalconEmail: |
Bruno LepriEmail: |
45.
Stephen R. Schach Tokunbo O. S. Adeshiyan Daniel Balasubramanian Gabor Madl Esteban P. Osses Sameer Singh Karlkim Suwanmongkol Minhui Xie Dror G. Feitelson 《Software Quality Journal》2007,15(1):99-113
Both common coupling and pointer variables can exert a deleterious effect on the quality of software. The situation is exacerbated
when global variables are assigned to pointer variables, that is, when an alias to a global variable is created. When this
occurs, the number of global variables increases, and it becomes considerably harder to compute quality metrics correctly.
However, unless aliasing is taken into account, variables may incorrectly appear to be unreferenced (neither defined nor used),
or to be used without being defined. These ideas are illustrated by means of a case study of common coupling in the Linux
kernel.
相似文献
Stephen R. SchachEmail: |
46.
The MultiDimER model is a conceptual model used for representing a multidimensional view of data for Data Warehouse (DW) and
On-Line Analytical Processing (OLAP) applications. This model includes a spatial extension allowing spatiality in levels,
hierarchies, fact relationships, and measures. In this way decision-making users can represent in an abstract manner their
analysis needs without considering complex implementation issues and spatial OLAP tools developers can have a common vision
for representing spatial data in a multidimensional model. In this paper we propose the transformation of a conceptual schema
based on the MultiDimER constructs to an object-relational schema. We based our mapping on the SQL:2003 and SQL/MM standards
giving examples of commercial implementation using Oracle 10g with its spatial extension. Further we use spatial integrity
constraints to ensure the semantic equivalence of the conceptual and logical schemas. We also show some examples of Oracle
spatial functions, including aggregation functions required for the manipulation of spatial data. The described mappings to
the object-relational model along with the examples using a commercial system show the feasibility of implementing spatial
DWs in current commercial DBMSs. Further, using integrated architectures, where spatial and thematic data is defined within
the same DBMS, facilitates the system management simplifying data definition and manipulation.
相似文献
Esteban ZimányiEmail: |
47.
In this paper, we introduce two algorithms to address the two-echelon capacitated location-routing problem (2E-CLRP). We introduce a branch-and-cut algorithm based on the solution of a new two-index vehicle-flow formulation, which is strengthened with several families of valid inequalities. We also propose an adaptive large-neighbourhood search (ALNS) meta-heuristic with the objective of finding good-quality solutions quickly. The computational results on a large set of instances from the literature show that the ALNS outperforms existing heuristics. Furthermore, the branch-and-cut method provides tight lower bounds and is able to solve small- and medium-size instances to optimality within reasonable computing times. 相似文献
48.
Qiuling Zou Qinghong Zhang Jingzhou Yang Aimee Cloutier Esteban Pena-Pitarch 《Computers & Industrial Engineering》2012
This paper presents a nonlinear inverse optimization approach to determine the weights for the joint displacement function in standing reach tasks. This inverse optimization problem can be formulated as a bi-level highly nonlinear optimization problem. The design variables are the weights of a cost function. The cost function is the weighted summation of the differences between two sets of joint angles (predicted posture and the actual standing reach posture). Constraints include the normalized weights within limits and an inner optimization problem to solve for joint angles (predicted standing reach posture). The weight linear equality constraints, obtained through observations, are also implemented in the formulation to test the method. A 52 degree-of-freedom (DOF) human whole body model is used to study the formulation and visualize the prediction. An in-house motion capture system is used to obtain the actual standing reach posture. A total of 12 subjects (three subjects for each percentile in stature of 5th percentile female, 50th percentile female, 50th percentile male and 95th percentile male) are selected to run the experiment for 30 tasks. Among these subjects one is Turkish, two are Chinese, and the rest subjects are Americans. Three sets of weights for the general standing reach tasks are obtained for the three zones by averaging all weights in each zone for all subjects and all tasks. Based on the obtained sets of weights, the predicted standing reach postures found using the direct optimization-based approach have good correlation with the experimental results. Sensitivity of the formulation has also been investigated in this study. The presented formulation can be used to determine the weights of cost function within any multi-objective optimization (MOO) problems such as any types of posture prediction and motion prediction. 相似文献
49.
Theoretical method for the study of plasmon generation in hybrid multilayer-optical fiber structures
A theoretical method is presented for the determination of the behavior of devices based on the deposition of multilayer structures on polished optical fibers. Plasmon generation in metallic layers is modeled. The method is based on the Rayleigh expansion of the electric fields and permits us to determine their distribution over the whole structure by an application of boundary conditions. Once the distribution is known, the power transmitted by the fiber can be computed as a function of the geometrical and refractive parameters of the device. The method is versatile and can be used as a theoretical tool for the design of devices of that type used for many different purposes. We present real experimental results obtained with an operative sensor that agree with the theoretical predictions of our technique and prove its suitability. 相似文献
50.