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241.
Due to the development of IT convergence, a wide variety of information is being produced and distributed rapidly in digital form. Lifelog based context awareness is a technology that provides a service automatically based on perceived situational information in ubiquitous environments. To offer customized services to users, the technology of acquiring lifelog based context information in real time is the most important consideration. We propose the interactive middleware architecture for lifelog based context awareness in distributed and ubiquitous environments. Conventional middleware to support ubiquitous environments stores and manages the situational information and service content acquired by centralized storage or a DBMS. Centralized situational information and service content management may impede the autonomy of mobile nodes and the interoperation between different middle software. The proposed method designs a system that can distribute and manage situational information in mobile nodes using mobile devices in distributed and ubiquitous environments and share the service content between interactive middleware through publication. The application system designed in this study was used in a scenario providing situational perception based mobile service and proved to be useful.  相似文献   
242.
Novel amphiphilic graft copolymers composed of poly(asparagine) (PAsn) as the hydrophilic backbone and poly(caprolactone) (PCL) as the hydrophobic segment were successfully synthesized by grafting PCL-HMDs to poly(succinimde). After tosylating PCL-diol with p-toluenesulfonylchloride (TsCl), tosylated poly(caprolactone) (PCL-OTs) was then reacted with hexamethylenediamine (HMD). The reaction of the amine terminated PCL with poly(succinimide) (PSI) and the following aminolysis resulted in poly(aspargine)-graft-poly(caprolactone) (PAsn-g-PCL). The degree of substitution (DS) and grafting reaction was confirmed by 13C NMR, FT-IR spectroscopy and elemental analysis. X-ray diffraction and DSC thermogram showed that the crystalline domain originated from PCL became apparent with an increase of DS. The amphiphilic comb-type graft polymer formed self-aggregates in aqueous solution when precipitated and dialysed against distilled water. Strong hydrophobic interaction of associated PCL grafts facilitated primary aggregate formation with DS, significantly reducing critical aggregation concentration and secondary aggregates also appeared in DLS measurements. Self-aggregates showed a bimodal size distribution originated from the self-aggregation and kinetically controlled particle aggregation, although the smaller primary aggregates was predominant. Spherical and dispersed aggregates of about 20 nm in diameter were observed by a transmission electron microscope.  相似文献   
243.
Cross docking is a logistic technique which seeks to reduce the inventory holding, order picking, transportation costs and delivery time. Little attention has been given to the transshipment operations inside a cross dock. In this article, we study the transshipment scheduling problem in a single receiving and a single shipping door cross dock under three scheduling policies: In the first policy, we assume to have complete information on the order of arrivals and the contents of all inbound trucks. The second and the third policies assume the availability of partial and no information on the sequence of upcoming trucks. An optimal graph based model is proposed for the full information case, and a polynomial time algorithm is given. Heuristics are developed for the other two cases. The comparison of the costs associated to each policy helps evaluating the value of information in cross dock scheduling problems.  相似文献   
244.
Abstract— In this article, a solution process for oxide thin‐film transistors (TFTs) at low‐temperature annealing was investigated. Solution‐process engineering, including materials and precursors, plays an important role in oxide thin‐film deposition on large glass and flexible substrates at low temperature. Reactive material could reduce the alloy reaction temperature for a multicomponent oxide system. A volatile precursor could also reduce annealing temperature in the formation of metal‐oxide thin films. A solution process with reactive Al and a volatile nitrate precursor can demonstrates competitive oxide TFTs at 350°C.  相似文献   
245.
246.
The development of earth‐abundant and efficient oxygen evolution reaction (OER) electrocatalysts is necessary for green hydrogen production. The preparation of efficient OER electrocatalysts requires both the adsorption sites and charge transfer on the catalyst surface to be suitably engineered. Herein, the design of an electrocatalyst is reported with significantly enhanced water oxidation performance via dual‐phase engineering, which displays a high number of adsorption sites and facile charge transfer. More importantly, a simple chemical etching process enables the formation of a highly metallic transition boride phase in conjunction with the transition metal hydroxide phase with abundant adsorption sites available for the intermediates formed in the OER. In addition, computational simulations are carried out to demonstrate the water oxidation mechanism and the real active sites in this engineered material. This research provides a new material design strategy for the preparation of high‐performance OER electrocatalysts.  相似文献   
247.
In this paper, we present a high image quality organic light‐emitting diode (OLED) display with motion blur reduction technology. Our latest work includes driving method that reduces motion blur using an adaptive black data insertion, brightness compensation technology, the simple structure pixel with low capacitance coupling for horizontal noise, and the multifunction integrated gate driver. The moving picture response time (MPRT) value of the OLED display panel with a fast response time was significantly affected by the frame frequency and the compensation driving method. The MPRT value of the large‐size OLED display panels was significantly decreased by using the integrated gate driver circuit with an MPRT reduction method. The decrease in the MPRT value originated from the turning of the emitting pixels off in advance resulting from providing black data. The integrated gate drivers were designed to achieve the normal display, the black data insertion, and the compensation mode. The MPRT value of the 65‐in. ultrahigh‐definition (UHD) OLED panels was decreased to 3.4 ms by using an integrated gate driver circuit. The motion blur of large‐size OLED display panels was significantly reduced due to a decrease in the MPRT value.  相似文献   
248.
Classical morphological analysis has been performed on novel PET fibers of high modulus and low shrinkage (HMLS). As expected, amorphous orientation controls the degree of shrinkage and tenacity. The uniqueness of these materials is derived from a high “effective” crosslink density which results in a high retractive force during elevated temperature shrinkage and significant stress-amplification during room temperature extension. Although the morphological origin of the high effective crosslink density is unknown, it is speculated that the interfibrillar regions contribute to the observed behavior by suppressing yielding.  相似文献   
249.
In this paper, we estimate the azimuth, the elevation, and the time of arrival of diffuse sources using the covariance matching estimator (COMET) algorithm. Previous works dealt with azimuth estimation of diffuse sources or azimuth and time of arrival estimation of point sources. However, in realistic situations, a tridimensional diffuse source localization is needed, which is the main objective of this paper. We show that the dimensionality of the COMET algorithm can be reduced by separating the estimation of the different source powers and the noise variance from that of the remaining parameters, namely the azimuth, the elevation, the time of arrival, and the corresponding angular and temporal spreads. As COMET still involves a multidimensional nonlinear optimization, we choose, in this purpose, the alternating projection algorithm to alleviate the corresponding complexity. The multiple signal classification (MUSIC) algorithm is processed to initialize the so-resulted algorithm. Simulations of the proposed algorithm are carried in different contexts and compared to the Cramér-Rao Bound, MUSIC algorithm, and dispersed signal parametric estimation simulation results.  相似文献   
250.
IT839 Strategy: the Korean challenge toward a ubiquitous world   总被引:1,自引:0,他引:1  
The South Korean government declared the IT839 Strategy as a new development strategy for the IT sector in 2004. Under this strategy, the introduction and development of eight (8) new IT services are expected to encourage investment in three (3) key network infrastructures, which in turn will promote the development of nine (9) new growth engines, including equipment, terminal, software, contents, and so on. Moreover, each of the 20 (8 + 3 + 9) sectors of the IT839 Strategy will reap synergistic effects as a result of concurrent growth through cooperation among the government, private sector, and research institutes. The IT839 Strategy is anchored on the belief that IT will bring about qualitative changes in the economic and social paradigm, ultimately aiming to realize a ubiquitous world by forming a virtual circle of developing new services, infrastructures, and growth engines.  相似文献   
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