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91.
The environmental load of fiber-reinforced polymer (FRP) reinforced pavement was compared with that of steel reinforced pavement. Replacing steel rebars with FRP rebars can lead to changes in the concrete mix and pavement structure at the erection stage, to a reduced need for maintenance activities related to steel corrosion, and to different recycling opportunities at the disposal stage. The current study examined all of these variables. The environmental load of FRP reinforced pavement was found to be significantly lower than that of steel reinforced pavement. This results mainly from the fact that FRP reinforced pavement requires less maintenance, its cement content and concrete cover over reinforcement can be reduced, and the reinforcement itself generates a smaller environmental load.  相似文献   
92.
Direct or indirect inter-residue interactions in proteins are often reflected by mutations at one site that compensate for mutations at another site. Various bioinformatic methods have been developed for detecting such correlated mutations in order to obtain information about intra- and inter-protein interactions. Here, we show by carrying out a correlated mutation analysis for non-interacting proteins that the signal due to inter-residue interactions is of similar magnitude to the 'noise' that arises from other evolutionary processes related to common ancestry. A new method for detecting correlated mutations is presented that reduces this evolutionary noise by taking into account evolutionary distances in the protein family. It is shown that this method yields better signal-to-noise ratios and, therefore, can much better resolve, for example, correlated mutations that reflect true inter-residue interactions.  相似文献   
93.
The leading living bacteria formulations currently available are from a limited list of genera and are generally limited to gastrointestinal tract syndromes. A formulation composed of living Bacillus subtilis incorporated in a thermoresponsive hydrogel that hardens after administration on the skin and continuously produces antifungal agents is described. The ability of the formula to support bacteria growth and its mechanical properties and penetrability through the skin are fine‐tuned by varying the ratio between polymer concentrations and bacterial media. The formula penetrates via the stratum corneum and accumulates in the epidermis without penetrating the inner, dermis layer. In vivo results mirror the results seen in vitro: bacillus formulations completely inhibit candida growth, demonstrating clinical effects comparable to those achieved by ketoconazole. LC‐MS/MS analysis of the bacterial formulation confirms the presence of surfactin, the most powerful biosurfactant that possesses a broad antifungal activity. This platform may enable rational design of novel formulations composed of secreting bacteria inside a responsive, smart, hydrogel—which is the prerequisite for producing a successful drug delivery system.  相似文献   
94.
Impagliazzo and Wigderson proved a uniform hardness vs. randomness gap theorem for BPP. We show an analogous result for AM: Either Arthur-Merlin protocols are very strong and everything in can be proved to a subexponential time verifier, or else Arthur-Merlin protocols are weak and every language in AM has a polynomial time nondeterministic algorithm such that it is infeasible to come up with inputs on which the algorithm fails. We also show that if Arthur-Merlin protocols are not very strong (in the sense explained above) then Our technique combines the nonuniform hardness versus randomness tradeoff of Miltersen and Vinodchandran with instance checking. A key ingredient in our proof is identifying a novel resilience property of hardness vs. randomness tradeoffs.  相似文献   
95.
Distributed constraint satisfaction with partially known constraints   总被引:1,自引:0,他引:1  
Distributed constraint satisfaction problems (DisCSPs) are composed of agents connected by constraints. The standard model for DisCSP search algorithms uses messages containing assignments of agents. It assumes that constraints are checked by one of the two agents involved in a binary constraint, hence the constraint is fully known to both agents. This paper presents a new DisCSP model in which constraints are kept private and are only partially known to agents. In addition, value assignments can also be kept private to agents and not be circulated in messages. Two versions of a new asynchronous backtracking algorithm that work with partially known constraints (PKC) are presented. One is a two-phase asynchronous backtracking algorithm and the other uses only a single phase. Another new algorithm preserves the privacy of assignments by performing distributed forward-checking (DisFC). We propose to use entropy as quantitative measure for privacy. An extensive experimental evaluation demonstrates a trade-off between preserving privacy and the efficiency of search, among the different algorithms. Partially supported by the Spanish project TIN2006-15387-C03-01. Partially supported by the Lynn and William Frankel center for Computer Sciences and the Paul Ivanier Center for Robotics and Production Management.  相似文献   
96.
A general conclusion, widely and uniformly supported by a variety of experiments, is that humans are unable to produce a random series of discrete responses, even when instructed to do so. Several arguments are advanced to show that the experimental evidence in support of this claim is plagued with logical and methodological difficulties. Using a new research paradigm, this article reports experimental results showing that people can generate binary sequences that satisfy standard tests of randomness more successfully when they participate in 2-person strictly competitive games inducing them to conceal their choices and protect themselves from their own frailty to maximize gain. The results are discussed within the framework of existing theories of cognitive biases in random-sequence generation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
In this paper, an immersion and invariance (I&I) adaptive fault tolerant satellite attitude tracking control scheme is proposed. The proposed controller is capable of track the desired trajectory in the presence of unknown actuator multiplicative faults and unknown inertial matrix. Also based on Lyapunov direct method, all closed loop signals are proven to be globally asymptotically stable. The main advantage of this controller is improving closed loop performance while maintaining stability in the presence of unknown actuator faults. This method does not rely on certainty equivalence principle so it can be used to control the transient response of overall closed loop system by means of controlling the parameter estimation behavior which is not possible in traditional adaptive control. Numerical simulations are performed to demonstrate the effectiveness of proposed control scheme.  相似文献   
98.
We study the renaming problem in a fully connected synchronous network with Byzantine failures. We show that when the original namespace of the processors is unbounded, this problem cannot be solved in an a priori bounded number of rounds for , where n is the size of the network and t is the number of failures. On the other hand, for n > 3t, we present a Byzantine renaming algorithm that runs in O(lg n) rounds. In addition, we present a fast, efficient strong renaming algorithm for n > t, which runs in rounds, where N 0 is the value of the highest identifier among all the correct processors.  相似文献   
99.
Informal reasoning fallacies are violations of critical discussion norms. As epistemological understanding of knowledge justification appears to underlie the informal reasoning skills of argument construction and evaluation, it was hypothesized that adolescents with greater epistemological sophistication would be more able to identify informal reasoning fallacies. It was hypothesized that 11th graders would be more epistemologically sophisticated than 7th or 9th graders and, thus, would more likely identify fallacies. Students responded to questions regarding argument scenarios that did or did not contain fallacies. More 11th graders identified fallacies. Epistemological level predicted only identification of one type of fallacy that might be described as epistemological in nature. Cognitive ability also seemed to contribute to the increased ability with grade to identify fallacies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Measuring the vague meanings of probability terms.   总被引:1,自引:0,他引:1  
Assessed membership functions over the [0,1] probability interval for several vague meanings of probability terms (e.g., doubtful, probable, likely), using a modified pair-comparison procedure in 2 experiments with 20 and 8 graduate business students, respectively. Ss performed 2 tasks in both experiments: They judged (A) to what degree one probability rather than another was better described by a given probability term and (B) to what degree one term rather than another better described a specified probability. Probabilities were displayed as relative areas on spinners. Task A data were analyzed from the perspective of conjoint-measurement theory, and membership function values were obtained for each term according to various scaling models. Findings show that the conjoint-measurement axioms were well satisfied and goodness-of-fit measures for the scaling procedures were high. Individual differences were large but stable, and the derived membership function values satisfactorily predicted the judgments independently obtained in Task B. Results indicated that the scaled values represented the vague meanings of the terms to the individual Ss in the present experimental context. (51 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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