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31.
Metallurgical and Materials Transactions A -  相似文献   
32.
FDAS: architecture and implementation   总被引:1,自引:0,他引:1  
Abstract: FDAS (Fabric Defects Analysis System) is a knowledge-based system (KBS) for diagnosing defects in woven textile structures. The following major issues were considered in the design of FDAS: (1) range of applications; (2) user profiles; (3) response time requirements; (4) modularity and (5) ease of system modification and enhancements. Knowledge about defects is represented in FDAS using a hierarchy of classes, with the slots representing defect attributes, and forward chaining rules. The inferencing process is controlled by slots of another distinct class hierarchy. Inference is made more efficient by hierarchical classification of the defects with pruning. The agenda (i.e. ordered set of hypotheses) is dynamically reset using actions attached to rules. The diagnosis information—information about the causes of the defects and remedial actions to be taken—is kept separate from the rules in the knowledge base. The user interface part of the system is also independent of the knowledge base, which facilitates easier tailoring of the system to meet the needs of different users. The user interaction with FDAS is menu-based and has been designed to minimize cognitive load on the user. FDAS has been extensively evaluated by in-house individuals who are experts in the task of fabric defects analysis. It has also been demonstrated to experts from the industry and is ready for field tests.  相似文献   
33.
A. Sarkar  G. Jayaraman 《Acta Mechanica》2002,158(1-2):105-119
Summary The effect of the irreversible boundary reaction on the dispersion of tracers in annular flows is studied. The solution of the mathematical model, based on the generalized dispersion model, brings out the dispersive transport following the injection of a tracer in terms of the three effective transport coefficients, viz. the exchange, the convection and the dispersion coefficients. It is found that the exchange and the convection coefficients are enhanced while the dispersion coefficient is reduced with the increase in the value of the absorption parameter.The mathematical model is applied to a specific problem in clinical medicine: dispersion of solutes in blood flow in a catheterized artery. The model predicts that the insertion of a catheter in general and any further increase in its size will enhance the process of the dyes or other solutes getting out of the blood vessels, and this is found to be independent of the absorption parameter representing the absorption properties of the blood vessel wall.  相似文献   
34.
EqL, a general-purpose language that combines the capabilities of functional and logic programming languages, is described. A program in EqL consists of a collection of conditional, pattern-directed rules, where the conditions are expressed as a conjunction of equations, and the patterns are terms built up of data-constructors and basic values. The computational paradigm in EqL is equation solving. Examples illustrating the major features of the language, nondeterminism, deferred evaluation of primitives, and logical variables are presented. The aspects of a sequential implementation for EqL, such as compile-time flattening of equations, run-time equation-delaying, and last-equation optimization, are also described  相似文献   
35.
The effects of fiber volume fraction (15, 37, and 41%) on fatigue crack growth in unidirectional SiC/Ti-15-3 composite were investigated at room temperature. The effect of fiber volume fraction on the fiber bridging mechanism was studied to support development of physically-based crack growth models. While each fiber volume fraction exhibits similar decreasing crack growth rates prior to fiber bridging induced crack arrest, post-arrest behavior (observed after incrementally increasing the applied stress level) is quite different. After crack arrest, the 15% (37 and 41%) material exhibited higher (lower) crack growth rates and lower (higher) toughness values than the unreinforced matrix. These different behaviors occur because of differences in the amount of fiber bridging during the post-arrest regime. Metallography of interrupted tests revealed the extent of fiber bridging in the crack wake and matrix plasticity ahead of the crack tip. Models for predicting the effective matrix stress intensities were evaluated and compared to experimental data. A fiber pressure model and finite element studies were used to estimate the condition of the bridged fiber zone and associated fiber stresses. Since the vast majority of useful life for these materials experiences fatigue crack growth, these results assist in discerning an optimum fiber volume fraction for structural applications.  相似文献   
36.
To determine whether counterregulation by interleukin (IL)-10 plays a role in the generation or maintenance of the antigen-specific hyporesponsiveness seen in asymptomatic microfilaremic (MF) patients, parasite antigen (PAg)- and nonparasite antigen (NPAg)-driven IL-10 production by peripheral blood mononuclear cells (PBMC) was studied in 10 MF patients and in ll patients with chronic lymphatic pathology (CP). PBMC from MF patients spontaneously secreted 10-fold more IL-10 than did PBMC from patients with CP. PAg also induced significantly more IL-10 production by PBMC from CP patients. There was a negative correlation between PAg driven IL-10 production by PBMC and PAg-specific T cell proliferation in the MF group. IL-10 secretion by plastic adherent cells from MF persons was higher in response to PAg than NPAg, whereas IL-6 and tumor necrosis factor-alpha secretion were equivalent for PAg and NPAg, suggesting that PAg preferentially induces IL-10 secretion in these cells. Thus, PAg-induced IL-10 likely plays an important role in down-regulating antigen-specific proliferative responses in MF patients.  相似文献   
37.
Enhancing the quality of life through wearable technology   总被引:14,自引:0,他引:14  
An overview of the key challenges facing the practice of medicine today is presented along with the need for technological solutions that can "prevent" problems. Then, the development of the Wearable Motherboard/spl trade/ (Smart Shirt) as a platform for sensors and monitoring devices that can unobtrusively monitor the health and well being of individuals (directly and/or remotely) is described. This is followed by a discussion of the applications and impact of this technology in the continuum of life-from preventing SIDS to facilitating independent living for senior citizens. Finally, the future advancements in the area of wearable, yet comfortable, systems that can continue the transformation of healthcare - all aimed at enhancing the quality of life for humans - are presented.  相似文献   
38.
Electronic textiles: A platform for pervasive computing   总被引:6,自引:0,他引:6  
The invention of the Jacquard weaving machine led to the concept of a stored "program" and "mechanized" binary information processing. This development served as the inspiration for C. Babbage's analytical engine-the precursor to the modern-day computer. Today, more than 200 years later, the link between textiles and computing is more realistic than ever. In this paper, we look at the synergistic relationship between textiles and computing and identify the need for their "integration" using tools provided by an emerging new field of research that combines the strengths and capabilities of electronics and textiles into one: electronic textiles, or e-textiles. E-textiles, also called smart fabrics, have not only "wearable" capabilities like any other garment, but also have local monitoring and computation, as well as wireless communication capabilities. Sensors and simple computational elements are embedded in e-textiles, as well as built into yarns, with the goal of gathering sensitive information, monitoring vital statistics, and sending them remotely (possibly over a wireless channel) for further processing. The paper provides an overview of existing efforts and associated challenges in this area, while describing possible venues and opportunities for future research.  相似文献   
39.
A 5-year-old girl with an asymptomatic posterior mediastinal cyst from birth was followed with repeated echocardiograms. The cyst developed communication with the bronchus spontaneously around 8 months of age without clinical symptoms. This was detected from the sudden disappearance of the mass on echocardiogram, and an unusual air-pocket on chest roentgenogram. Computed tomography (CT) of the chest confirmed the diagnosis of communicating bronchogenic cyst (BC). She was treated successfully with complete surgical excision of the cyst and closure of the defect in the bronchus. We emphasize that surgery is indicated in all mediastinal BCs because of potential complications.  相似文献   
40.
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