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In this work, the minimization of the ripple in the relative change of the transfer function amplitude due to parameter variations is studied for the signal-flow graph of the state equations realizing all-pole second-order transfer function. First the measure for the ripple is defined and then branch transmittances minimizing the measure are found. the results obtained in this study can be used in all-pole active filter realizations with the minimum ripple measure.  相似文献   
33.
The Data Locality of Work Stealing   总被引:1,自引:0,他引:1  
This paper studies the data locality of the work-stealing scheduling algorithm on hardware-controlled shared-memory machines, where movement of data to and from the cache is solely controlled by the hardware. We present lower and upper bounds on the number of cache misses when using work stealing, and introduce a locality-guided work-stealing algorithm and its experimental validation. {As a lower bound, we show that a work-stealing application that exhibits good data locality on a uniprocessor may exhibit poor data locality on a multiprocessor. In particular, we show a family of multithreaded computations G n whose members perform Θ(n) operations (work) and incur a constant number of cache misses on a uniprocessor, while even on two processors the total number of cache misses soars to Ω(n) . On the other hand, we show a tight upper bound on the number of cache misses that nested-parallel computations, a large, important class of computations, incur due to multiprocessing. In particular, for nested-parallel computations, we show that on P processors a multiprocessor execution incurs an expected
more misses than the uniprocessor execution. Here m is the execution time of an instruction incurring a cache miss, s is the steal time, C is the size of cache, and T fty is the number of nodes on the longest chain of dependencies. Based on this we give strong execution time bounds for nested-parallel computations using work stealing.} For the second part of our results, we present a locality-guided work-stealing algorithm that improves the data locality of multithreaded computations by allowing a thread to have an affinity for a processor. Our initial experiments on iterative data-parallel applications show that the algorithm matches the performance of static-partitioning under traditional work loads but improves the performance up to 50% over static partitioning under multiprogrammed work loads. Furthermore, locality-guided work stealing improves the performance of work stealing up to 80%.  相似文献   
34.
The limitations of the photolithography-based micromachining technologies defines the upper-bound on the performance and robustness of micromachined gyroscopes. Conventional gyroscope designs based on matching (or near-matching) the drive and sense modes are extremely sensitive to variations in oscillatory system parameters that shift the natural frequencies and introduce quadrature errors. Nonconventional design concepts have been reported that increase bandwidth to improve robustness, but with the expense of response gain reduction. This paper presents a new approach that may yield robust vibratory MEMS gyroscopes with better gain characteristics while retaining the wide bandwidth. The approach is based on utilizing multiple drive-mode oscillators with incrementally spaced resonance frequencies to achieve wide-bandwidth response in the drive-mode, leading to improved robustness to structural and thermal parameter fluctuations. Enhanced mode-decoupling is achieved by distributing the linear drive-mode oscillators radially and symmetrically, to form a multidirectional linear drive-mode and a torsional sense-mode; minimizing quadrature error and zero-rate output. The approach has been implemented on bulk-micromachined prototypes fabricated in a silicon-on-insulator (SOI)-based process, and experimentally demonstrated.  相似文献   
35.
The aim of the present study was to formulate suspension type inhalation aerosols by various types of auxiliary materials, and to select the formulation with the highest proportion of the effective particle size. The examined suspension type aerosol contained sodium cromoglycate as an active compound. For the stabilization of the suspension, the applied surface active ingredients were oleic acid and oleyl oleate, and dimethyl siloxane polymer was selected as hydrophobizing agent. Factorial design was used for the optimization of the experimental results. On the basis of our results, the correct types and amounts of auxiliary materials can be selected to obtain the therapeutically effective formulation.  相似文献   
36.
Acar  C. 《Electronics letters》1973,9(8):186-187
A new and simple derivation of Chen's multiple-node removal algorithm is given, starting from signal-flowgraph equations and using only Mason's gain formula.  相似文献   
37.
Karag?z  C. Acar  C. 《Electronics letters》1982,18(22):966-967
A general synthesis method is given for the realisation of nth-order voltage transfer functions in the z-domain by active SC (switched-capacitor) networks using only biphased switches, capacitors and ideal operational amplifiers. The method presented is based on signal-flow graphs and the resulting networks are completely insensitive to stray capacitances.  相似文献   
38.
In present study, the effective penetration of radiofrequency (RF) induced gold decorated iron oxide nanoparticles (GS@IONPs) hyperthermia was investigated. The effective penetration depth of RF also the damage potency of hyperthermia was evaluated during histopathology observations which were done on the chicken breast tissue and hepatocellular carcinoma (HCC) models. The thermal damages are well‐ documented in our previous cellular study which was engaged with potency of RF hyperthermia in Epithelial adenocarcinoma (MCF‐7) and fibroblast (L‐929) cells deaths [1]. In recent work, PEGylated iron oxide nanoparticles (IONPs) were used as base platform for gold magnetic nanoparticles (GS@IONPs) formation. The 144.00015 MHz, 180W RF generator was applied for stimulating the nanoparticles. The chicken breast tissue and the hepatocellular tumor model was considered in the experimental section. In histology studies, the structural changes also the effective penetration depth of RF induced nanoparticles was observed through microscopic monitoring of the tissue slices in histology observations (Gazi medical school). The highest damage level was seen in 8.0 µm tissue slices where lower damages were seen in depth of 1.0 cm and more inside tissue. The histology observations clarified the effective penetration depth of RF waves and irreversible damages in the 2.0 cm inside the tissue.Inspec keywords: nanomedicine, tumours, biomedical materials, cellular biophysics, nanoparticles, gold, cancer, hyperthermia, magnetic particles, iron compounds, radiation therapyOther keywords: Au‐Fe3 O4 , depth 1.0 cm, depth 8.0 mum, power 180.0 W, size 2.0 cm, frequency 144.00015 MHz, microscopic monitoring, structural changes, hepatocellular tumour model, standing wave ratio, propylene glycol, thermal damages, hepatocellular carcinoma models, radiofrequency hyperthermia, nanoparticle dispersion, tissue alterations, modified tissues, gold shell magnetic nanoparticles, chicken breast tissue, gold‐coated iron oxide nanoparticles, pathology observations, effective penetration depth, histology observations, tissue slices  相似文献   
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