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71.
Spaceborne and airborne sensors in water quality assessment   总被引:1,自引:0,他引:1  
Remotely sensed data can increase the ability of water resources researchers and decision-makers to monitor waterbodies more effectively. In recent decades, remote-sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e. suspended sediments, coloured dissolved organic matter (CDOM), chlorophyll-a, and pollutants). A large number of different sensors on board various satellites and other platforms, such as aeroplanes, are currently used to measure the amount of radiation at various wavelengths reflected from the water’s surface. In this review article, the more commonly employed spaceborne and airborne sensors used in water quality investigations are introduced and their utility in the quantitative assessment of the quality parameters of waterbodies is discussed. Various properties (spectral, spatial and temporal, etc.) of spaceborne and airborne sensors are tabulated to be used as a sensor selection guide. These tables are helpful when designing water quality assessment studies, and can be used for the selection of appropriate sensors among many other available sensors in the market. Finally, based on the literature survey, a compilation of sensors used to measure various water quality parameters is presented.  相似文献   
72.
Multiparty Key Agreement (MKA) is the backbone for secure multiparty communication. Although numerous efficient MKA-cryptosystems are available in the classical field, their security relies on the assumption that some computational issues are infeasible. To overcome this dependency, a new area, quantum cryptography, evolves to support key agreement among two or more participants securely. In this paper, first, we present a two-part quantum key agreement with Strong Fairness Property (SFP) and extends it to a Multiparty Quantum Key Agreement (MQKA) protocol. In the first round of proposed MQKA, a participant will act as a group controller (GC) and establishes two-party groups with each of the residual participants and agreed on a quantum two-party-style shared key per each of the two-party. In the second round, the GC computes public keys for each of the respective parties by combining these two-party keys using XOR-operation, excluding that party’s two-party key. Next, the GC sends separate public keys to the individual participants. After receiving the respective public-key, each of the respective participants computes the multiparty key by joining their public-key with their two-party key using XOR. Finally, GC computes the multiparty key, as the GC knows all the two-party keys, it combines them with XOR and acts as a usual group participant. The proposed protocol has compared with other renowned MQKA protocols in terms of four standards parameters, namely transmission number (TN), qubit measurement number (QM), qubit for channel checking (QCC), and the qubit efficiency (QE) and acceptable results achieved. The security of the proposed MQKA relies on the absolute security of a two-part quantum key agreement with Strong Fairness Property (SFP). Moreover, it is secure against both internal and external attacks.  相似文献   
73.
A general dynamic-compilation environment offers power and performance control opportunities for microprocessors. The authors propose a dynamic-compiler-driven runtime voltage and frequency optimizer. A prototype of their design, implemented and deployed in a real system, achieves energy savings of up to 70 percent.  相似文献   
74.
DYPLAS is a computer program designed to compute the response history of general three-dimensional structures subjected to transient thermal and mechanical loadings. The analysis considers nonlinearities arising from material behavior as well as from large deformations that may occur in the structure. Elastic-plastic behavior with isotropic hardening is included by means of incremental relations of the Prandtl-Reuss type combined with a variant of the ‘plastic strain-total strain’ method. Reduction of the constitutive relations to the case of generalized plane stress is also presented. Spatial discretization is achieved by applying the displacement formulation of the finite element method. In order to achieve reasonable computational time, the number of computational points used in the algorithm for numerical integration over the volume of each finite element required minimization; a triangular, flat-plate bending element is cited as an example for which this minimization was achieved satisfactorily. An explicit scheme is used for computation of dynamic response. With this scheme, formation of a global stiffness matrix is not needed. Consequently, the usual limitations arising from bandwidth or problem size are completely eliminated.  相似文献   
75.
The role of Al and Ag dopants in the nominal composition, 4336 of Bi-Sr-Ca-Cu oxide has been studied, using a new chemical phase analysis method known as differential dissolution besides XRD and resistivity and magnetic susceptibility measurements. Our investigation reveals that (a) it is relatively easy to realize high-T c phase (2223) in both Al- and Ag-doped samples with the same nominal composition and heat treatment history (b) both samples consist of superconducting phases with more or less the same basic composition and equal amounts, (c) 2112 phase may be a superconductor and (d) superconducting properties with Al and Ag dopants are different.  相似文献   
76.
Complementary DNA encoding the putative mouse homologue for human acrosomal protein SP-10, a candidate contraceptive vaccinogen, was cloned and sequenced. The entire open reading frame (amino acids 18 to 261) of the mouse SP-10 (mSP-10), with the exception of the signal peptide (amino acids 1 to 17), was placed under the influence of inducible T7 RNA polymerase/promoter system to overproduce recombinant protein (re-mSP-10) in Escherichia coli. A six-histidine tag, which was coexpressed at the carboxyl terminus of re-mSP-10, provided the means for purification of re-mSP-10 by immobilized metal chelation affinity chromatography technique. The level of purity of re-mSP-10 thus obtained was determined by 2-dimensional gel electrophoresis to be 98%. Immunoblotting with monoclonal and polyclonal antibodies previously generated against human or baboon SP-10 showed that mSP-10 shared significant antigenic similarity with its primate counterparts. The position of mSP-10 in the mouse genome was next mapped through segregation analysis of an interspecific backcross panel of 96 animals. Acrv1 (assigned gene symbol for mSP-10) was localized in the proximal portion of mouse chromosome 9 in a region that exhibits synteny with human 11q23, the region to which ACRV1 (gene symbol for human SP-10) was previously mapped. These characterizations by combined immunological and gene mapping techniques established the cloned mSP-10 to be the mouse homologue of SP-10.  相似文献   
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