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21.
Context
Existing test suite prioritization techniques usually rely on code coverage information or historical execution data that serve as indicators for estimating the fault-detecting ability of test cases. Such indicators are primarily empirical in nature and not theoretically driven; hence, they do not necessarily provide sound estimates. Also, these techniques are not applicable when the source code is not available or when the software is tested for the first time.Objective
We propose and develop the novel notion of fault-based prioritization of test cases which directly utilizes the theoretical knowledge of their fault-detecting ability and the relationships among the test cases and the faults in the prescribed fault model, based on which the test cases are generated.Method
We demonstrate our approach of fault-based prioritization by applying it to the testing of the implementation of logical expressions against their specifications. We then validate our proposal by an empirical study that evaluates the effectiveness of prioritization techniques using two different metrics.Results
A theoretically guided fault-based prioritization technique generally outperforms other techniques under study, as assessed by two different metrics. Our empirical results also show that the technique helps to reveal all target faults by executing only about 72% of the prioritized test suite, thereby reducing the effort required in testing.Conclusions
The fault-based prioritization approach is not only applicable to the instance empirically validated in this paper, but should also be adaptable to other fault-based testing strategies. We also envisage new research directions to be opened up by our work. 相似文献22.
Economic lot-scheduling problem (ELSP) has been studied since the 1950??s. ELSP deals with the scheduling of the production of several items on a single facility in a cyclical pattern. The facility can only produce one single item at a time, and there is a set-up cost and set-up time associated with each item. Because of the rapid development of many emerging markets nowadays, many common items are produced in different places in order to satisfy the demands in different markets. This becomes the multi-facilities ELSP problems. In ELSP problems, it is known that if more items types to be produced by the facility, the production frequency of each item type will increase because of the balancing of the production rate and the demand rate. Consequently, the number of set-up time and set-up cost increases accordingly. Thus, reallocating the common items, which can be produced in any facilities, to be produced only on certain facility can certainly reduce the number of production frequency, and lead to lower related costs. The objective of this paper is to propose an optimization methodology combining Integer Programming and Genetic Algorithm to solve multi-facility ELSP problems. This paper proposes to divide the main problem into a master problem and sub-problems, which are solved by Integer Programming and Genetic Algorithm respectively. To demonstrate the significance of reallocating the common items and aggregating them to produce in certain facility, several models have been designed and tested. The comparison of the models demonstrates the reduction of the costs benefited by result of common items reallocation. 相似文献
23.
Psychoudakis D. Volakis J. L. Wing Z. Halloran J. H. 《Antennas and Propagation, IEEE Transactions on》2006,54(12):3586-3592
Use of high permittivity dielectrics with antennas is known to reduce their operating frequency but also introduces side effects such as reduced gain and bandwidth. This paper presents a miniaturization scheme for a 15 cm (6 inch) square circularly polarized (CP), cavity-backed antenna using textured dielectric loading and a folded metallic strip feed. The proposed design has an operational frequency f, around 500 MHz implying a linear size of 0.25lambda0. The challenge in designing such a small size antenna is to increase bandwidth (10-15%) while retaining a gain of 2-4 dBi. By carefully positioning high permittivity textured dielectrics within the aperture in conjunction with shape design, we show that bandwidth and gain are retained as compared to comparable size antennas in the literature. As part of our design, we present parametric studies through computer simulations and a prototype antenna is fabricated and measured for verification 相似文献
24.
Presented in this paper are the results of a research project on the monitoring and assessment of the first link slab jointless bridge in the state of North Carolina. The structure was instrumented with a remote data acquisition system and monitored for over a year. In addition, a controlled load test was conducted in an effort to determine the demand on the link slab under known loads. A procedure for the limit-states design of a link slab system is also presented. Results indicate that while the crack size in the link slab exceeded the design level, the link slab fulfilled its function. Furthermore, the rotational demand from the large controlled loads as well as the traffic loads was similar in magnitude to the thermal induced rotations due to the difference in temperature between the top and bottom of the bridge. 相似文献
25.
This paper identifies managers who require ethics training in using IT at work. The identification of these managers is mainly based on studying the impact of their individual characteristics on a set of seven ethical issues and attitudes, which translated into IT ethical scenarios. This paper proposes a canonical model by treating individual characteristics of managers as predictor variables and considering information describing their beliefs on those seven ethical issues and attitudes as explained variables. A questionnaire survey was used for data collection and 249 managers participated in this study. The results show that the significant explained variables are based on a combination of six ethical events of accountability, conflict of interest, disclosure, personal conduct, protection of privacy, and social responsibility. The significant predictor variables are based on a combination of four individual characteristics of age, educational level, organizational level, and working experience. Discussion on the implication of the results and recommendations for remedial action are also provided in this paper. 相似文献
26.
A multi-user 3-D virtual environment allows remote participants to have a transparent communication as if they are communicating face-to-face. The sense of presence in such an environment can be established by representing each participant with a vivid human-like character called an avatar. We review several immersive technologies, including directional sound, eye gaze, hand gestures, lip synchronization and facial expressions, that facilitates multimodal interaction among participants in the virtual environment using speech processing and animation techniques. Interactive collaboration can be further encouraged with the ability to share and manipulate 3-D objects in the virtual environment. A shared whiteboard makes it easy for participants in the virtual environment to convey their ideas graphically. We survey various kinds of capture devices used for providing the input for the shared whiteboard. Efficient storage of the whiteboard session and precise archival at a later time bring up interesting research topics in information retrieval. 相似文献
27.
28.
Phil Surman Ian Sexton Richard Bates Wing Kai Lee Kam Chaun Yow 《Journal of the Society for Information Display》2004,12(2):153-158
Abstract— Under the European Union funded Advanced Three‐dimensional Television System Technologies (ATTEST) project, De Montfort University (DMU) is developing a 3D display system targeted specifically at domestic television applications. This system uses a modified transmissive LCD panel together with novel backlighting and optics to project multiple viewing regions, or exit pupils, into the viewing space. These exit pupils are located in space using a head tracker. The display accommodates multiple viewers simultaneously and imposes no physical constraints, such as special eyewear. Viewers may move freely over a “typical” room‐sized area. The design of the backlighting facilitates many other display regimes beyond the “standard” 3DTV mode in which each viewer sees the same image pair. 相似文献
29.
游桂芬 《中北大学学报(自然科学版)》1992,(3)
本文研究了一种用于超声波钢轨探伤的软件抗干扰算法。该算法中采用了抗干扰矩阵,可快速有效地区分有用信号及干扰信号。 相似文献
30.
We introduce a new class of solvable finite dimensional estimation algebras that contains both the linear and the Bene
cases. The condition for finite dimensionality is expressed in terms of two matrices. They play an important role in understanding the structure of estimation algebras. 相似文献