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961.
Digital twin represents a fusion of the informational and physical domains, to bridge the material and virtual worlds. Existing methods of digital twin modeling are mainly based on modular representation, which limits guidance of the modeling process. Such methods do not consider the components or operational rules of the digital twin in detail, thereby preventing designers from applying these methods in their fields. With the increasing application of digital twin to various engineering fields, an effective method of modeling a multi-dimensional digital twin at the conceptual level is required. To such an end, this paper presents a method for the conceptual modeling of a digital twin based on a five-dimensional digital twin framework to represent the complex relationship between digital twin objects and their attributes. The proposed method was used to model the digital twin of an intelligent vehicle at the concept level. 相似文献
962.
To fulfill increasingly difficult and demanding tasks in the ever-changing complex world, intelligent industrial products are to be developed with higher flexibility and adaptability. Digital twin (DT) brings about a possible means, due to its ability to provide candidate behavior adjustments based on received “feedbacks” from its physical part. However, such candidate adjustments are deterministic, and thus lack of flexibility and adaptability. To address such problem, in this paper an extended concept – evolutionary digital twin (EDT) and an EDT-based new mode for intelligent industrial product development has been proposed. With our proposed EDT, a more precise approximated model of the physical world could be established through supervised learning, based on which the collaborative exploration for optimal policies via parallel simulation in multiple cyberspaces could be performed through reinforcement learning. Hence, more flexibility and adaptability could be brought to industrial products through machine learning (such as supervised learning and reinforcement learning) based self-evolution. As a primary verification of the effectiveness of our proposed approach, a case study has been carried out. The experimental results have well confirmed the effectiveness of our EDT based development mode. 相似文献
963.
Assessment with computer agents that engage in conversational dialogues and trialogues with learners
This article describes conversation-based assessments with computer agents that interact with humans through chat, talking heads, or embodied animated avatars. Some of these agents perform actions, interact with multimedia, hold conversations with humans in natural language, and adaptively respond to a person’s actions, verbal contributions, and emotions. Data are logged throughout the interactions in order to assess the individual’s mastery of subject matters, skills, and proficiencies on both cognitive and noncognitive characteristics. There are different agent-based designs that focus on learning and assessment. Dialogues occur between one agent and one human, as in the case of intelligent tutoring systems. Three-party conversations, called trialogues, involve two agents interacting with a human. The two agents can take on different roles (such as tutors and peers), model actions and social interactions, stage arguments, solicit help from the human, and collaboratively solve problems. Examples of assessment with these agent-based environments are presented in the context of intelligent tutoring, educational games, and interventions to help struggling adult readers. Most of these involve assessment at varying grain sizes to guide the intelligent interaction, but conversation-based assessment with agents is also currently being used in high stakes assessments. 相似文献
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966.
H. T. Nguyen V. Kreinovich 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》1997,1(4):198-209
We show that epistemic specifications, proposed by M. Gelfond and H. Przymusinska in [4], lead to a natural justification
of several heuristic methods used in expert systems and in intelligent control.
This paper is an overview of several results, some of which have already been published before. In contrast to the original
publications, that were targeted specifically towards researchers that design and analyze traditional (degree of certainty,
MYCIN-type) expert systems and intelligent control systems, we present the corresponding results in such a way that they become
understandable (and hopefully, natural) to the logic programming community as well.
The relationship between epistemic specifications and heuristic methods not only makes heuristic methods more reliable, it
also adds confidence that the formalism of epistemic specifications, as proposed by M. Gelfond and H. Przymusinska, is an
appropriate formalization of knowledge: Indeed, the fact that the language of epistemic specifications, that was originally
proposed without any numerical degree of certainty in mind, turns out to be quite consistent with (practically successful)
number-valued heuristics, is a strong argument in favor of this language.
Received: 18 March 1997/Accepted: 13 May 1997 相似文献
967.
在未来高技术局部战争条件下,坦克不得不面临一个动态复杂的战场环境,这就要求坦克能根据战场环境实时地进行任务规划。以单辆坦克在陆地上的自主机动为背景,提出了一种基于智能搜索的坦克机动任务规划方法。在机动任务规划的实施方面,重点描述了两个基本方面:坦克机动环境的评估及坦克机动任务规划的自主实现。构造了一种智能搜索方法,同时应用这种方法提出了实现坦克自主机动的基本思路,并编制应用程序,进行实例检验。结果表明,这种方法科学合理,为坦克机动任务的规划提供了新思路。神经网络评估方法具有普遍意义,能推广应用于坦克其它方面的任务规划。 相似文献
968.
969.
《Ergonomics》2012,55(9):1233-1248
In the context of emergency warnings, auditory icons, which convey information about system events by analogy with everyday events, have the potential to be understood more quickly and easily than abstract sounds. To test this proposal, an experiment was carried out to evaluate the use of auditory icons for an invehicle collision avoidance application. Two icons, the sounds of a car horn and of skidding tyres, were compared with two conventional warnings, a simple tone and a voice saying ‘ahead’. Participants sat in an experimental vehicle with a road scene projected ahead, and they were required to brake in response to on-screen collision situations and their accompanying warning sounds. The auditory icons produced significantly faster reaction times than the conventional warnings, but suffered from more inappropriate responses, where drivers reacted with a brake press to a non-collision situation. The findings are explained relative to the perceived urgency and inherent meaning of each sound. It is argued that optimal warnings could be achieved by adjusting certain sound attributes of auditory icons, as part of a structured, user-centred design and evaluation procedure. 相似文献
970.
F.?DeraviEmail author M.C.?Fairhurst R.M.?Guest N.J.?Mavity A.M.D.?Canuto 《Universal Access in the Information Society》2003,2(4):293-304
Current approaches to personal identity authentication using a single biometric technology are limited, principally because no single biometric is generally considered both sufficiently accurate and user-acceptable for universal application. Multimodal biometrics can provide a more adaptable solution to the security and convenience requirements of many applications. However, such an approach can also lead to additional complexity in the design and management of authentication systems. Additionally, complex hierarchies of security levels and interacting user/provider requirements demand that authentication systems are adaptive and flexible in configuration. In this paper we consider the integration of multimodal biometrics using intelligent agents to address issues of complexity management. The work reported here is part of a major project designated IAMBIC (Intelligent Agents for Multimodal Biometric Identification and Control), aimed at exploring the application of the intelligent agent metaphor to the field of biometric authentication. The paper provides an introduction to a first-level architecture for such a system, and demonstrates how this architecture can provide a framework for the effective control and management of access to data and systems where issues of privacy, confidentiality and trust are of primary concern. Novel approaches to software agent design and agent implementation strategies required for this architecture are also highlighted. The paper further shows how such a structure can define a fundamental paradigm to support the realisation of universal access in situations where data integrity and confidentiality must be robustly and reliably protected . 相似文献