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1.
Carbohydrates and their conjugates play important roles in many biological processes including fertilization, differentiation, development, immune response, and infection. Their activities are largely dependent on the properties of terminal mono‐ or disaccharides. Galactose, mannose, fucose, glucose, sialic acid, etc., are commonly used as powerful scaffolds installed on drug molecules for targeting specific tissues including brain, liver, and cancers, and as epitopes for enhancing the targeting of various vaccines. This review focuses on the influence of their structural variations, including changes in sugar type, substituent groups and their positions, as well as length of linker portion, on the targeting of drugs or their efficacy. Particular attention is paid to the targeting properties of mono‐ and disaccharides applied in drug design and discovery.  相似文献   
2.
Managing sports performance is very important in the sports industry. Performance, the executives, centers on boosting competitor execution and decreasing the danger of injury. Several factors contribute to these goals, including player health, emotional status, exercise load and physical intensity requirements. Generally speaking, injury prediction is an essential component of injury prevention, and successful identification of injury prediction is a primary indicator for effective prevention. The proposed Artificial Neural Network (ANN) objective is to develop and use early-doing ability and exercise load data to validate a hierarchical machine learning prediction system with accurate detection of player injuries. The physical and workload that requires detection of this early personalized damage can be avoided with specific help. The framework is used to test 21 soccer players’ sports information from various sources, including gathered and inside burden information, outside burden information, and review information. The entirety of this information is fused into the proposed framework to improve the exactness of harm expectation. This calculation distinguishes competitors in danger of injury, with their early intervention available.  相似文献   
3.
我国《2006-2020年国家信息化发展战略》提出要加强卫生信息化建设;2011年3月卫生部发布《基于电子病历的医院信息平台建设技术解决方案》;2011年10月国家中医药管理局发布《中医医院信息化建设基本规范》。以上都为我国各个县级中医医院的信息化提供了技术支撑和统一要求。结合我国县市级中医医院的现状,对其网络硬件基础设施平台的设计进行探讨,以满足其发展及国家对医疗机构的信息化要求。  相似文献   
4.
In the request-based scheme, a patching channel is initiated on arrival of a request in an interarrival time of two adjacent multicast channels. If two requests are received in a short duration in an interarrival time, two patching channels are needed to service them. Both these channels deliver almost the same data, thus, wasting the bandwidth. This problem may be addressed in two ways: using higher level patching technique, or forcing the first request to wait for the second one. Using higher level patching technique makes the system more complex and thus usually not preferred. In the second case, the bandwidth usage certainly reduces, but the length of the waiting time by the first request for the second request is the main issue. In this paper, this issue is addressed by dividing the video duration into uniform time slots such that there is at least one request in a time slot for initiating the patching channel. The proposed scheme is named as Video Data Delivery using Slotted Patching. In this scheme, the patching channels download much less video data than the request-based scheme and thus require less bandwidth. This scheme may not provide immediate services to all users unlike the request-based scheme, but the user's waiting can be made arbitrarily small without using much resources unlike the request-based scheme.  相似文献   
5.
李鹏  王建新  丁长松 《自动化学报》2016,42(11):1648-1656
可靠高效的数据收集是无线传感器网络(Wireless sensor networks,WSN)应用中的关键问题.然而,由于无线通信链路的高失效率、节点资源受限以及环境恶劣等原因,网络容易发生丢包问题,使得现有的数据收集方法无法同时满足高精度和低能耗的要求.为此,本文提出了一种基于压缩感知的高能效数据收集方案.该方案主要分为节点上的数据处理和数据收集路径优化两个步骤.首先设计了基于指数核函数的稀疏矩阵来对感知数据进行稀疏化处理,然后综合考虑了数据的传输能耗和可靠性等因素,采用分块矩阵的思路,将单位矩阵和准循环低密度奇偶校验(Low density parity check,LDPC)码的校验矩阵相结合构造了测量矩阵,并证明了它与稀疏矩阵之间满足限制等距性质(Restricted isometry property,RIP).最后,将数据收集路径优化问题建模为哈密尔顿回路问题,并提出了基于树分解的路径优化算法进行求解.仿真结果表明,在网络存在丢包的情况下,本文方案仍然能够保证数据收集的高精确度,相比于其他数据收集方案而言,本文方案在数据重构误差和能耗方面的性能更优.  相似文献   
6.
The photoluminescence (PL) and vacuum ultraviolet (VUV) excitation properties are studied for the BaZr(BO3)2:Eu3+ phosphor with incorporating the Al3+, La3+, or Y3+ ion into the lattice. The excitation spectrum shows an absorption band in the VUV region with the band-edge at 200 nm and a very weak charge transfer band of Eu3+ at about 226 nm. The luminescence spectrum shows a strong emission at 615 nm (5D0  7F2 transition) and weak emission at 594 nm (5D0  7F1 transition) in BaZr(BO3)2:Eu3+, with a good red color purity. The PL intensity is increased by incorporating Al3+ into the BaZr(BO3)2 lattice. The PL intensity has also increased by incorporating La3+ into the lattice, however, the red color purity has deteriorated because of the increased centrosymmetric nature of the site. With the incorporation of Y3+ into the BaZr(BO3)2 lattice, the PL characteristics of the Eu3+ activator resembles that in the YBO3 lattices. The intensity of the red PL for the Eu3+ activator is the highest with good color purity for BaZr(BO3)2:Eu3+ incorporated with both Al3+ (10%) and La3+ (0.5%).  相似文献   
7.
8.
The Chan–Vese (C–V) model is an ineffective method for processing images in which the intensity is inhomogeneous. This is especially true for multi-object segmentation, in which the target may be missed or excessively segmented. In addition, for images with rich texture information, the processing speed of the C–V is slow. To overcome these problems, this paper proposes an effective multi-object C–V segmentation model based on region division and gradient guide. First, a rapid initial contour search is conducted using Otsu’s method. This contour line becomes the initial contour for our multi-object segmentation C–V model based on a gradient guide. To achieve the multi-object segmentation the image is then converted to a single level set whose evolution is controlled using an adaptive gradient. The feasibility of the proposed model is analyzed theoretically, and a number of simulation experiments are conducted to validate its effectiveness.  相似文献   
9.
In this paper the synthesis and characterization of microporous polymer microspheres with ultra-high specific surface areas (>1000 m2/g) and strong cation-exchange character is described. The microspheres were synthesized by the hypercrosslinking of swellable precursor particles which had been produced by precipitation polymerization. The strong cation-exchange character, arising from the presence of sulfonic acid groups, was introduced through post-hypercrosslinking chemical modification reactions. Two alkyl sulfate reagents of differing polarity were compared as reagents for the sulfonation reactions, and a synthetic methodology was devised that allowed the sulfonic acid content of the microspheres to be controlled. Following a series of small-scale optimization experiments, optimized conditions were applied on a larger scale to the synthesis of three distinct polymers (HXLPP-SCX) tailored for use as strong cation-exchange (SCX) sorbents in solid-phase extraction (SPE) studies. All three polymers were in the form of polymer microspheres (mean particle diameters 3–5 μm) with relatively narrow particle size distributions and specific surface areas up to 1370 m2/g, and had tuneable ion-exchange capacities (IECs) ranging from 1.7–2.8 mmol/g.  相似文献   
10.
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