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121.
The authors examined predictors of psychological distress among women who were at increased risk for ovarian cancer. Participants were 103 women who had at least 1 first degree relative with ovarian cancer. Specifically, the authors tested the relationship between the dispositional attentional style of monitoring (the tendency to scan for threat-relevant information), perceptions of risk for ovarian cancer, intrusive thoughts regarding ovarian cancer, and psychological distress. Overall, this sample exhibited moderately high levels of psychological distress. High scores on monitoring were associated with high perceived risk for ovarian cancer and elevated levels of intrusive thoughts and psychological distress. Finally, the authors proposed and tested a path model describing the interrelationships between these variables. Results of this study are discussed in terms of their implications for treating the psychological distress associated with being at increased risk for ovarian cancer. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
123.
More than 100 bacterial isolates from various marine habitats were screened for AHL production by using gfp reporter constructs based on the lasR system of Pseudomonas aeruginosa and the luxR system of Vibrio fischeri. Of the 67 Alphaproteobacteria tested, most of which belonged into the so-called Roseobacter clade, 39 induced fluorescence in either one or both sensor strains up to 103-fold compared to controls. Acylated homoserine lactones were identified by GC-MS analysis and shown to have chain lengths of C8, C10, C13-C16, and C18. One or two double bonds were often present, while a keto or hydroxyl group occurred only rarely in the side chain. Most strains produced several different AHLs. C18-en-HSL and C18-dien-HSL were produced by Dinoroseobacter shibae, an aerobic anoxygenic phototrophic bacterium isolated from dinoflagellates, and are among the longest AHLs found to date. Z7-C14-en-HSL, which has previously been detected in Rhodobacter sphaeroides, was produced by Roseovarius tolerans and Jannaschia helgolandensis. This signal molecule was synthesised and shown to induce a similar response to the culture supernatant in the respective sensor strain. The widespread occurrence of quorum-sensing compounds in marine Alphaproteobacteria, both free-living strains and those associated to eukaryotic algae, points to a great importance of this signalling mechanism for the adaptation of the organisms to their widely different ecological niches.  相似文献   
124.
A method for unification as the basis for intelligent backtracking in deduction systems is described. This method is based on the unification graphs introduced by Cox. In this paper, unification graphs are used in an extended form such that they represent all the information which can be gained from the unification constraints, i.e., the expression to be unified, their subterms which, as a consequence, are to be unified, the number of deduction steps which cause the unification of two terms, and the term-subterm relation as far as necessary. If a unification conflict occurs from this information, the deduction steps which have led to these conflicts can be determined and reset. This is done by searching for loop-free paths or loops with certain properties in the extended unification graph, according to the type of unification conflict. Algorithms for the handling of the unification graph and for the extraction information from it are described and proved as correct.  相似文献   
125.
We developed a chemical method to quantitate lead in small skeletal specimens and used it to establish lead distribution and quantitation in modern skeletons for all age groups to standardize sampling sites. Application of the method to excavated ancient skeletal collections enabled prediction of socioeconomic status among Colonial Americans, as well as identification of lead poisoning in ancient Rome as related to lead production and in an 18th century Caribbean epidemic as related to distillation of rum. Depending upon the conditions of burial, bones may be contaminated by surrounding material. This can be a limiting factor for interpretation of lead levels, but multielement analysis and procedural modifications can permit continuing application of bone lead analysis to appropriately selected archaeological skeletal collections.  相似文献   
126.
Speech emotion recognition has been one of the interesting issues in speech processing over the last few decades. Modelling of the emotion recognition process serves to understand as well as assess the performance of the system. This paper compares two different models for speech emotion recognition using vocal tract features namely, the first four formants and their respective bandwidths. The first model is based on a decision tree and the second one employs logistic regression. Whereas the decision tree models are based on machine learning, regression models have a strong statistical basis. The logistic regression models and the decision tree models developed in this work for several cases of binary classifications were validated by speech emotion recognition experiments conducted on a Malayalam emotional speech database of 2800 speech files, collected from ten speakers. The models are not only simple, but also meaningful since they indicate the contribution of each predictor. The experimental results indicate that speech emotion recognition using formants and bandwidths was better modelled using decision trees, which gave higher emotion recognition accuracies compared to logistic regression. The highest accuracy obtained using decision tree was 93.63%, for the classification of positive valence emotional speech as surprised or happy, using seven features. When using logistic regression for the same binary classification, the highest accuracy obtained was 73%, with eight features.  相似文献   
127.
World Wide Web - Due to the popularity of Spatial Databases, many search engine providers have started to expand their text searching capability to include geographical information. Because of this...  相似文献   
128.
In order to improve the intraoperative applications, this paper presents the advantages of using Guyton's model in hypotensive control system development. In this system, the mean arterial pressure is decreased and maintained at a low level during anaesthesia by controlling sodium nitroprusside infusion rate. The key of the study is to develop a physiological model of cardiovascular dynamics to present the mean arterial pressure response to sodium nitroprusside, which was considered as a linear model in most of known blood pressure control systems. Being linear, the previous models cannot accurately mimic a physiological system of human circulation, especially at deep hypotensive control with strong reaction of the body. The enhanced model in this study was modified based on Guyton's model of human circulation. It is useful to design a PID controller, which allows studying and handling the wide range of the body sensitivities. This model is also helpful for studying the behaviors of patients under anaesthesia conditions, such as the perfusion of organs and the reaction of the body at hypotensive state. A fuzzy gain scheduler and a supervising algorithm were also developed for online tuning the controller to handle the behavior of the body. The control system was tested on 25 experiments on seven pigs in the animal laboratory. Simulation and experiment results proved the usefulness of Guyton's model in control system design which can present the dynamical response of blood pressure in the circulation under and after hypotensive control. The results also indicated the safety and stability of the controller.  相似文献   
129.
The widespread availability of personal mobile devices, combined with the increasing availability of stationary public devices such as large interactive displays, creates new opportunities for computer-supported collaborative work. In particular, these two factors enable the emergence of collaborative scenarios, whether planned or spontaneous, in any location, and previous obstacles to such collaborative settings such as limitations on the number of devices available for use and infrastructure costs can be overcome more easily. As hardware restrictions diminish, the need for software toolkits that simplify the development of distributed collaborative applications allowing for device heterogeneity, true multi-user interaction and spontaneous emergence increases. In this article, we describe the Toolkit for Web-based Interactive Collaborative Environments whose aim is to address these issues. This is done using current standard web technologies extended for real-time application (and structured using specific development guidelines) while ensuring compatibility with the manifold new evolutions in the currently ongoing development of open web platform (HTML5, websockets, etc). While our own work has mainly focused on synchronous co-located collaborative systems (same place/same time), our solution, the technologies used, as well as the concepts that are introduced are easily extendable for remote and/or asynchronous collaboration.  相似文献   
130.
The distillation based separation can be extremely complex if highly non-ideal mixtures are to be separated. In spite of different successfully applied unit operations there is still a possible way to improve the distillation technique and widen its toolbar. A new improvement in this area is the development of the extractive heterogeneous-azeotropic distillation (EHAD). This unit operation includes the merits of extractive- and heterogeneous-azeotropic distillations in one unit without extra material addition. Our work supports EHAD features with successful experiments compared with modelling and comparison with other separation structures proving that the application of EHAD makes the separation of extremely non-ideal mixtures possible on an easy, powerful, energy saving, and cost efficient way.  相似文献   
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