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191.
State feedback control of continuous-time T-S fuzzy systems via switched fuzzy controllers 总被引:1,自引:0,他引:1
This paper studies the problem of state feedback control of continuous-time T-S fuzzy systems. Switched fuzzy controllers are exploited in the control design, which are switched based on the values of membership functions, and the control scheme is an extension of the parallel distributed compensation (PDC) scheme. Sufficient conditions for designing switched state feedback controllers are obtained with meeting an H∞ norm bound requirement and quadratic D stability constraints. It is shown that the new control design method provides less conservative results than the corresponding ones via the parallel distributed compensation (PDC) scheme. A numerical example is given to illustrate the effectiveness of the proposed method. 相似文献
192.
Suboptimal robust synthesis for MIMO nominal system under coprime factor perturbations is considered in classical and non-classical statements. In the classical statement, weights of perturbations and upper bound on magnitude bounded exogenous disturbance are assumed to be known to controller designer. Suboptimal synthesis within ε tolerance is reduced to the solution of log2(1/ε) standard mixed sensitivity problems of ℓ1 optimization. In the non-classical statement, the upper bounds on perturbations and exogenous disturbance are to be estimated from measurement data and suboptimal synthesis is reduced to the solution of 1/ε mixed sensitivity problems. 相似文献
193.
In an organization operating in the bancassurance sector we identified a low-risk IT subportfolio of 84 IT projects comprising together 16,500 function points, each project varying in size and duration, for which we were able to quantify its requirements volatility. This representative portfolio stems from a much larger portfolio of IT projects. We calculated the volatility from the function point countings that were available to us. These figures were aggregated into a requirements volatility benchmark. We found that maximum requirements volatility rates depend on size and duration, which refutes currently known industrial averages. For instance, a monthly growth rate of 5% is considered a critical failure factor, but in our low-risk portfolio we found more than 21% of successful projects with a volatility larger than 5%. We proposed a mathematical model taking size and duration into account that provides a maximum healthy volatility rate that is more in line with the reality of low-risk IT portfolios. Based on the model, we proposed a tolerance factor expressing the maximal volatility tolerance for a project or portfolio. For a low-risk portfolio its empirically found tolerance is apparently acceptable, and values exceeding this tolerance are used to trigger IT decision makers. We derived two volatility ratios from this model, the π-ratio and the ρ-ratio. These ratios express how close the volatility of a project has approached the danger zone when requirements volatility reaches a critical failure rate. The volatility data of a governmental IT portfolio were juxtaposed to our bancassurance benchmark, immediately exposing a problematic project, which was corroborated by its actual failure. When function points are less common, e.g. in the embedded industry, we used daily source code size measures and illustrated how to govern the volatility of a software product line of a hardware manufacturer. With the three real-world portfolios we illustrated that our results serve the purpose of an early warning system for projects that are bound to fail due to excessive volatility. Moreover, we developed essential requirements volatility metrics that belong on an IT governance dashboard and presented such a volatility dashboard. 相似文献
194.
A multi-objective controller synthesis problem is considered in which an output is to be regulated approximately by assuring a bound on the steady-state peak amplification in response to an infinite-energy disturbance, while also guaranteeing a desired level of performance measured in terms of the worst-case energy gain from a finite-energy input to a performance output. Relying on a characterization of the controllers with which almost asymptotic regulation is accomplished, the problem of guaranteeing the desired level of performance is reduced to solving a system of linear matrix inequalities subject to a set of linear equality constraints. Based on the solution of this system, a procedure is outlined for the construction of a suitable controller whose order is equal to the order of the plant plus the order of the exogenous system. 相似文献
195.
control with limited communication and message losses 总被引:2,自引:0,他引:2
We propose an H∞ approach to a remote control problem where the communication is constrained due to the use of a shared channel. The controller employs a periodic time sequencing scheme for message transmissions from multiple sensors and to multiple actuators of the system. It further takes into account the information on the random message losses that occur in the channel. An exact characterization for controller synthesis is obtained and is stated in terms of linear matrix inequalities. Furthermore, an analysis on the loss probabilities of the messages to accomplish stabilization is carried out. The results are illustrated through a numerical example. 相似文献
196.
In this paper, by using the concept of (A,η)-accretive mappings and the new resolvent operator technique associated with (A,η)-accretive mappings, we introduce and study a system of general mixed quasivariational inclusions involving (A,η)-accretive mappings in Banach spaces, and construct a new perturbed iterative algorithm with mixed errors for this system of nonlinear (A,η)-accretive variational inclusions in q-uniformly smooth Banach spaces. Our results improve and generalize the corresponding results of recent works. 相似文献
197.
李悦乔 《数字社区&智能家居》2009,(12)
探讨了在C语言程序设计教学过程中为学生建立相应的思维模式的方法问题。针对非计算机专业学生基础差、专业性不强的特点,结合当前DIY的潮流,分析了C语言的基本结构,分析了RPGMaker中提供的技术可行性,提出通过促进学生使用RPG-Maker软件来制作游戏以建立相应的程序设计思维模式的方法,并提出具体案例供参考。实践表明,学生的程序设计思维能较快速、熟练地建立起来。 相似文献
198.
陈淑芬 《数字社区&智能家居》2009,(29)
首先阐述计算机辅助设计在高职类院校计算机专业课程中开设的必要性。再结合教师实际教学经验,分块讨论计算机辅助设计在机械制图中的应用,给出相应教学内容及教学方法,以便更好地为高职院校课程的开设提供帮助。 相似文献
199.
A perceived limitation of evolutionary art and design algorithms is that they rely on human intervention; the artist selects
the most aesthetically pleasing variants of one generation to produce the next. This paper discusses how computer generated
art and design can become more creatively human-like with respect to both process and outcome. As an example of a step in
this direction, we present an algorithm that overcomes the above limitation by employing an automatic fitness function. The
goal is to evolve abstract portraits of Darwin, using our 2nd generation fitness function which rewards genomes that not just
produce a likeness of Darwin but exhibit certain strategies characteristic of human artists. We note that in human creativity,
change is less choosing amongst randomly generated variants and more capitalizing on the associative structure of a conceptual
network to hone in on a vision. We discuss how to achieve this fluidity algorithmically.
相似文献
Liane GaboraEmail: |
200.
Reza Samavi Eric Yu Thodoros Topaloglou 《Information Systems and E-Business Management》2009,7(2):171-198
Strategic reasoning about business models is an integral part of service design. In fast moving markets, businesses must be able to recognize and respond strategically to disruptive change. They have to answer questions such as: what are the threats and opportunities in emerging technologies and innovations? How should they target customer groups? Who are their real competitors? How will competitive battles take shape? In this paper we define a strategic modeling framework to help understand and analyze the goals, intentions, roles, and the rationale behind the strategic actions in a business environment. This understanding is necessary in order to improve existing or design new services. The key component of the framework is a strategic business model ontology for representing and analyzing business models and strategies, using the i* agent and goal oriented methodology as a basis. The ontology introduces a strategy layer which reasons about alternative strategies that are realized in the operational layer. The framework is evaluated using a retroactive example of disruptive technology in the telecommunication services sector from the literature. 相似文献