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991.
A mobile-agent-based approach to software coordination in the HOOPE system   总被引:3,自引:0,他引:3  
Software coordination is central to the construction of large-scale high-performance distributed applications with software services scattered over the decentralized Internet. In this paper, a new mobile-agent-based architecture is proposed for the utilization and coordination of geographically distributed computing resources. Under this architecture, a user application is built with a set of software agents that can travel across the network autonomously. These agents utilize the distributed resources and coordinate with each other to complete their task. This approach' s advantages include the natural expression and flexible deployment of the coordination logic, the dynamic adaptation to the network environment and the potential of better application performance. This coordination architecture, together with an object-oriented hierarchical parallel application framework and a graphical application construction tool, is implemented in the HOOPE environment, which provides a systematic support for the de  相似文献   
992.
In this paper we propose a novel scheme for scheduling divisible task on parallel processors connected by system interconnection network with arbitrary topology,The divisible task is a computation that can be divided into arbitrary independent subtasks solved in parallel.Our model takes into consideration communication initial time and communication delays between processors.Moreover,by constructing the corresponding Network Spanning present the concept of Balanced Task Distribution Tree and use it to design the Equation Set Creation Algorithm in which the set of linear equations is created by traversing the NST in Post-order.After solving the created equations,we get the optimal task assignment scheme.Experiments confirm the applicability of our scheme in real-life situations.  相似文献   
993.
Waiting time appears to be an unavoidable part of the service industry, particularly at the airport, where you may encounter delays due to check-in, screening, and other activities. This waiting experience can vex customers, affecting their perception of the service provider and, consequently, their loyalty. Our study aimed to determine the effect of waiting time satisfaction and the use of self-service technology on the long-term sustainability of customer loyalty. 750 structured questionnaires were distributed to travelers at two international airports in Turkey. PLS-SEM was used to analyses the models. Our findings indicate that customer satisfaction with waiting times and the use of self-service technologies are critical for the long-term sustainability of customer loyalty. Additionally, we discovered that waiting time satisfaction partially mediates the relationship between self-service technology use and long-term customer loyalty. Finally, the managerial implications were discussed, including future research suggestions.  相似文献   
994.
Stretchable microsupercapacitors represent emerging miniaturized energy-storage devices for next-generation deformable electronics. Two-dimensional (2D) transition metal carbides (MXenes) are considered attractive electrode materials due to their metallic conductivity, hydrophilic surfaces, and excellent processability. Here, an ultrastretchable microsupercapacitor of interdigitated MXene microelectrodes with crumpled surface textures is created. The microsupercapacitor shows a series of attractive properties including a high specific capacitance of ≈185 mF cm−2, ultrahigh stretchability up to 800% area strain, and ≈89.7% retention of the initial capacitance after 1000 stretch–relaxation cycles. In addition to static strains, the microsupercapacitor demonstrates robust mechanical properties to retain stable charging–discharging capability under dynamic stretching at different strain rates. A self-powering circuit system utilizes four microsupercapacitor packs to power a light-emitting diode (LED) array, which exhibits stable operations under large tensile strain and skin-attached wearable settings. The developments offer a generic design strategy to enhance the deformability of microsupercapacitors based on 2D nanomaterials.  相似文献   
995.
Hemispherical image sensors simplify lens designs, reduce optical aberrations, and improve image resolution for compact wide-field-of-view cameras. To achieve hemispherical image sensors, organic materials are promising candidates due to the following advantages: tunability of optoelectronic/spectral response and low-temperature low-cost processes. Here, a photolithographic process is developed to prepare a hemispherical image sensor array using organic thin film photomemory transistors with a density of 308 pixels per square centimeter. This design includes only one photomemory transistor as a single active pixel, in contrast to the conventional pixel architecture, consisting of select/readout/reset transistors and a photodiode. The organic photomemory transistor, comprising light-sensitive organic semiconductor and charge-trapping dielectric, is able to achieve a linear photoresponse (light intensity range, from 1 to 50 W m−2), along with a responsivity as high as 1.6 A W−1 (wavelength = 465 nm) for a dark current of 0.24 A m−2 (drain voltage = −1.5 V). These observed values represent the best responsivity for similar dark currents among all the reported hemispherical image sensor arrays to date. A transfer method was further developed that does not damage organic materials for hemispherical organic photomemory transistor arrays. These developed techniques are scalable and are amenable for other high-resolution 3D organic semiconductor devices.  相似文献   
996.
利用脉冲激光沉积法制备了(La1-xTbx)2/3Sr1/3MnO3系列薄膜样品。在77-300K的温度范围内,对样品的微观结构、磁化强度、电阻率和巨磁电阻效应等物理性质进行了系统研究。随着Tb含量x的增大,铁磁-顺磁转变温度随之下降,在x=0. 33样品中,最大磁化场μ0H=1.2T时,观察到34%的巨磁电阻。本文对其机理进行了研究和讨论。  相似文献   
997.
对象式软件需求模型及其机器支撑   总被引:3,自引:0,他引:3  
为了研究需求级软件自动化技术,研制对象式软件需求分析支撑系统的需要,文章提出了一个层次化对象式软件需求模型NDHORM(Nanjing daxue hierarchical object-oriented requirements modelling),它主要包括对象关系模型、类关系模型和类字典3个组成部分.文章基于对对象式需求模型的简要讨论,详细介绍了NDHORM模型的组成、层次结构及对象精化,给出了NDHORM的构模过程,最后简要介绍了NDHORM模型的机器支撑系统.  相似文献   
998.
群通信在并行计算中起着重要的作用.ATM(asynchronous transfer mode)网络有许多特点使之适合群通信.如何有效地利用ATM的这些特点来实现群通信操作是一个重要的研究课题.该文提出了一种基于ATM的群通信结构——混合树(Hybrid-Tree),该结构适合动态组中的群通信,并且能有效地利用ATM的特点.文中提出的组管理协议和树结构维护方法很好地解决了树结构的维护问题.  相似文献   
999.
模糊关系数据库查询语言FSQL   总被引:1,自引:0,他引:1  
模糊数据库是模糊信息处理系统的重要组成部分。本文以SQL语言为基础,设计了模糊关系数据库查询语言FSQL。FSQL语言采用了模糊值模糊关系数据模型,提供了相应的模糊数据定义与模糊数据操纵功能。为了便于模糊信息的表示和管理,FSQL语言增加了模糊数据类型,如简单标量型、模糊标量型、简单数集、模糊数集等。另外,为了便于模糊查询,扩充了模糊比较库函数及自定义隶属函数。  相似文献   
1000.
混合型学习模型HLM中的增量学习算法   总被引:4,自引:0,他引:4  
混合型学习模型HLM将概念获取算法HMCAP和神经网络算法FTART有机结合,能学习多概念和连续属性,其增量学习算法建立在二叉混合判定树结构和FTART网络的基础上,在给系统增加新的实例时,只需进行一遍增量学习调整原结构,不用重新生成判定树和神经网络,即可提高学习精度,速度快、效率高.本文主要介绍该模型中的增量学习算法.  相似文献   
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