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991.
    
Personnel selection is a very important activity in the human resource management of an organization. However, in many practical circumstances, due to time pressure and lack of information about candidates, decision makers generally tend to provide linguistic assessments and use different linguistic term sets to express their opinions during the personnel selection process. In this article, the VIKOR method combined with interval 2‐tuple linguistic variables is proposed to choose appropriate individuals among candidates in a group decision‐making environment. The interval 2‐tuple linguistic variable, which comprises two linguistic terms and two real numbers, is more flexible and precise to deal with linguistic information in solving personnel selection problems. To demonstrate the applicability and effectiveness of the proposed interval 2‐tuple linguistic VIKOR method, a numerical example of personnel selection in a tertiary care hospital is provided.  相似文献   
992.
    
The purpose of this study is to develop a decision support system (DSS) for the technical sustainability assessment of water distribution systems (WDSs). The technical sustainability is assessed based on the sustainability index methodology using reliability, resiliency, and vulnerability as performance criteria. These performance criteria are visualized by the DSS combining several visualization techniques to improve the raw data readability and the effectiveness of the decision-making process. The technical sustainability of the existing WDS is assessed using the sustainability index methodology and two alternative scenarios are proposed to improve the sustainability. The “new pump” scenario is based on adding network components. The second scenario is based on using reclaimed water for non-potable water demand and fire flow. The results show that the DSS is effective to illustrate time-dependent variables in the WDS and that the sustainability index methodology is a credible approach to compare scenarios and to identify problematic locations.  相似文献   
993.
    
Failure mode and effects analysis (FMEA), as a usefulness and powerful risk assessment tool, has been widely utilized in different industries for improving the safety and reliability of systems. However, the conventional risk priority number (RPN) method shows some important weaknesses when applied in actual situations. Moreover, FMEA is a group decision behavior and FMEA team members tend to use different linguistic term sets to express their judgments because of their different backgrounds and preferences, some of which may be imprecise, uncertain and incomplete. In this paper, we propose a new risk priority model using interval 2-tuple hybrid weighted distance (ITHWD) measure to solve the problems and improve the performance of the traditional FMEA. The new model can not only handle the uncertainty and diversity of FMEA team members’ assessment information but also consider the subjective and objective weights of risk factors in the risk ranking process. The model has exact characteristic and can avoid information distortion and loss in the linguistic information processing. Finally, a case study of blood transfusion is provided to demonstrate the effectiveness and benefits of the proposed approach.  相似文献   
994.
    
Facility location selection problem is one of the challenging and famous kinds of MCDM problems including both quantitative and qualitative criteria. For each Multiple Criteria Decision Making (MCDM) problem, when the ratings of alternatives with respect to the criteria and/or the values of criteria’s weights are presented by Interval Valued Fuzzy Numbers (IVFNs), the conventional fuzzy MCDM methods (Type-1 fuzzy MCDM methods) tend to be less effective. Therefore, the IVF-MCDM (Interval Valued Fuzzy MCDM) methods should be applied for solving such fuzzy MCDM problems. In this paper, we propose an IVF-VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje) method based on uncertainty risk reduction in decision making process. By using such method, the reliability of the captured decisions in an IVF decision making problem is significantly increased. The proposed method is applied for solving two numerical examples that the former of which is a real application problem related to selecting a suitable location for digging some pits for municipal wet waste landfill in one of the largest cities in Iran. The second numerical example is presented with an aim of comparing our method with the two other IVF-MCDM methods. As a result, we found out the proposed method is reliable and practical for the facility location selection problems and other MCDM problems. Moreover, the proposed method has a considerable accuracy and is flexible and easy to use.  相似文献   
995.
    
Based on the preference ranking organization method for enrichment evaluations (PROMETHEE), the purpose of this paper is to develop a new multiple criteria decision-making method that uses the approach of likelihood-based outranking comparisons within the environment of interval type-2 fuzzy sets. Uncertain and imprecise assessment of information often occurs in multiple criteria decision analysis (MCDA). The theory of interval type-2 fuzzy sets is useful and convenient for modeling impressions and quantifying the ambiguous nature of subjective judgments. Using the approach of likelihood-based outranking comparisons, this paper presents an interval type-2 fuzzy PROMETHEE method designed to address MCDA problems based on interval type-2 trapezoidal fuzzy (IT2TrF) numbers. This paper introduces the concepts of lower and upper likelihoods for acquiring the likelihood of an IT2TrF binary relationship and defines a likelihood-based outranking index to develop certain likelihood-based preference functions that correspond to several generalized criteria. The concept of comprehensive preference measures is proposed to determine IT2TrF exiting, entering, and net flows in the valued outranking relationships. In addition, this work establishes the concepts of a comprehensive outranking index, a comprehensive outranked index, and a comprehensive dominance index to induce partial and total preorders for the purpose of acquiring partial ranking and complete ranking, respectively, of the alternative actions. The feasibility and applicability of the proposed method are illustrated with two practical applications to the problem of landfill site selection and a car evaluation problem. Finally, a comparison with other relevant methods is conducted to validate the effectiveness of the proposed method.  相似文献   
996.
    
Security threats against computer networks and the Internet have emerged as a major and increasing area of concern for end-users trying to protect their valuable information and resources from intrusive attacks. Due to the amount of data to be analysed and the similarities between attack and normal traffic patterns, intrusion detection is considered a complex real world problem. In this paper, we propose a solution that uses a genetic algorithm to evolve a set of simple, interval-based rules based on statistical, continuous-valued input data. Several innovations in the genetic algorithm work to keep the ruleset small. We first tune the proposed system using a synthetic data. We then evaluate our system against more complex synthetic data with characteristics associated with network intrusions, the NSL-KDD benchmark dataset, and another dataset constructed based on MIT Lincoln Laboratory normal traffic and the low-rate DDoS attack scenario from CAIDA. This new approach provides a very compact set of simple, human-readable rules with strongly competitive detection performance in comparison to other machine learning techniques.  相似文献   
997.
    
This paper concerns the study of average consensus in wireless sensor networks with aim of providing a way to reach consensus in a finite number of steps. In particular, we investigate the design of consensus protocols when, for security reasons for instance, the underlying graph is constrained to be strongly regular or distance regular. The proposed design method is based on parameters of the intersection array characterizing the underlying graph. With this protocol, at execution time, average consensus is achieved in a number of steps equal to the diameter of the graph, i.e. the smallest possible number of steps to achieve consensus.  相似文献   
998.
    
In this article, we present a general representation for constraint satisfaction problems with disjunctive relations called cluster constraint systems (CCS). For this representation, we develop a novel and simple approach for solving CCSs using convex envelopes. These envelopes can be used to decompose the feasible space of the CCS through convex approximations. We explore interval reasoning as a case study of CCS. Our experimental results demonstrate that such CCS can be effectively and efficiently solved through convex enveloping with very modest branching requirements in comparison to other generic as well as specialized algorithms for interval reasoning. In fact, convex enveloping solves significantly more cases and more efficiently than other methods used in our test bed.  相似文献   
999.
    
Abstract

This paper centres on the generalization/specialization relation in the framework of conceptual graphs (this relation corresponds to logical subsumption when considering logical formulas associated with conceptual graphs). Results given here apply more generally to any model where knowledge is described by labelled graphs and reasoning is based on graph subsumption, as in semantic networks or in structural machine learning. The generalization/specialization relation, as defined by Sowa, is first precisely analysed, in particular its links with a graph morphism, called projection. Besides Sowa's specialization relation (which is a preorder), another one is actually used in some practical applications (which is an order). These are comparatively studied. The second topic of this paper is the design of efficient algorithms for computing these specialization relations. Since the associated problems are NP-hard, the form of the graphs is restricted in order to arrive at polynomial algorithms. In particular, polynomial algorithms are presented for computing a projection from a conceptual ‘tree’ to any conceptual graph, and for counting the number of such projections. The algorithms are also described in a generic way, replacing the projection by a parametrized graph morphism, and conceptual graphs by directed labelled graphs.  相似文献   
1000.
    
In this article, finite-time consensus algorithms for a swarm of self-propelling agents based on sliding mode control and graph algebraic theories are presented. Algorithms are developed for swarms that can be described by balanced graphs and that are comprised of agents with dynamics of the same order. Agents with first and higher order dynamics are considered. For consensus, the agents' inputs are chosen to enforce sliding mode on surfaces dependent on the graph Laplacian matrix. The algorithms allow for the tuning of the time taken by the swarm to reach a consensus as well as the consensus value. As an example, the case when a swarm of first-order agents is in cyclic pursuit is considered.  相似文献   
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