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1.
Algebraic theory of optimal filterbanks   总被引:1,自引:0,他引:1  
We introduce an optimality theory for finite impulse response (FIR) filterbanks using a general algebraic point of view. We consider an admissible set /spl Lscr/ of FIR filterbanks and use scalability as the main notion based on which performance of the elements in /spl Lscr/are compared. We show that quantification of scalability leads naturally to a partial ordering on the set /spl Lscr/. An optimal solution is, therefore, represented by the greatest element in /spl Lscr/. It turns out that a greatest element does not necessarily exist in /spl Lscr/. Hence, one has to settle with one of the maximal elements that exist in /spl Lscr/. We provide a systematic way of finding a maximal element by embedding the partial ordering at hand in a total ordering. This is done by using a special class of order-preserving functions known as Schur-convex. There is, however, a price to pay for achieving a total ordering: there are infinitely many possible choices for Schur-convex functions, and the optimal solution specified in /spl Lscr/ depends on this (subjective) choice. An interesting aspect of the presented algebraic theory is that the connection between several concepts, namely, principal component filterbanks (PCFBs), filterbanks with maximum coding gain, and filterbanks with good scalability, is clearly revealed. We show that these are simply associated with different extremal elements of the partial ordering induced on /spl Lscr/ by scalability.  相似文献   
2.
Journal of Computer-Aided Molecular Design - In the field of drug–target interactions prediction, the majority of approaches formulated the problem as a simple binary classification task....  相似文献   
3.
A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a non-Markovianity witness is particularly useful, being easily computable since no diagonalization of the system density matrix is required. We investigate the sensitivity of this HSS-based witness to detect non-Markovianity in various high-dimensional and multipartite open quantum systems with finite Hilbert spaces. We find that the time behaviors of the HSS-based witness are always in agreement with those of quantum negativity or quantum correlation measure. These results show that the HSS-based witness is a faithful identifier of the memory effects appearing in the quantum evolution of a high-dimensional system with a finite Hilbert space.  相似文献   
4.
In the present work, dispersive liquid-liquid microextraction based on solidification of floating organic drop was developed as a simple and rapid technique for separation of silver ions from aqueous samples. In this technique, 700 μL 0.02% of 5-(4'-dimethylamino benzyliden)-rhodanine (chelating agent) was added into the 10 mL analyte sample in a test tube and 30.0 μL 1-undecanol (extraction solvent) was injected shortly thereafter. The test tubes were sonicated, centrifuged and then some effective parameters on extraction and complex formation, such as type and volume of extraction and disperser solvent, pH, the amount of chelating agent and extraction time were optimized. The effect of the interfering ions on the analytes recovery was also investigated. The calibration graph was linear in the range of 0.10-10.0 ng mL(-1) with detection limit of 0.056 ng mL(-1) (n=8). The relative standard deviation (RSD) was ±4.3% (n=8, C=5.0 ng mL(-1)) and the enrichment factor was 250.0. The proposed method was applied for extraction and determination of silver in different water samples.  相似文献   
5.
6.
Journal of Signal Processing Systems - The acoustic signals radiated from the marine vessels contain information about their machinery characteristics that can be useful for the detection and...  相似文献   
7.
A novel synthesis of 1,2,4-oxadiazoles is described from a one-pot, three-component reaction between nitriles, hydroxylamine, and aldehydes under microwave irradiation and solvent-free conditions in excellent yields.  相似文献   
8.
The preparation of several bis(1,4-diazepinium) salts from the reaction of three 1,2-diamines with a bis(vinamidinium) salt is described. Bis(γ-substituted pentamethine cyanine(dyes are also prepared from the reaction of vinamidinium salt with 1,2-dimethylquinolinium perchlorate and 1,2,3,3-tetramethyl-3H-indolium perchlorate. Data from elemental analyzes, IR, 1H-NMR, 13C-NMR, and mass spectra (MS) confirm the molecular structure of the obtained products.  相似文献   
9.
System identification based on least mean square (LMS) adaptive filters is effective due to their simplicity and robustness. Inherent physical characteristic of intended system usually make nonnegativity constraint desirable. In other words, imposing nonnegativity constraint on optimization problem leads to more feasible unknown parameter estimation. Hence, nonnegative least mean square (NNLMS) and its variants were proposed to adaptively solve the Wiener filtering problem considering constraint that makes filter weights nonnegative. In this paper, we propose a new variant of nonnegative least mean square for which its performance is analyzed both theoretically and experimentally. The proposed algorithm behavior is investigated in sparse system identification by Monte Carlo simulations in order to show validation of analysis and theory models. We compare our method with IP-NNLMS and NNLMS in order to prove the advantage of our proposed algorithm. Our proposed algorithm is also used in classification problem, and it is compared with entropy function-based online adaptive decision fusion (EADF) algorithm.  相似文献   
10.
The organometallic palladium complex with nitrogen-containing heterocycles is a potent antitumor agent. Coordination of phosphorus ligands to organometallic complexes increases their hydrophilicity, promotes ligand−DNA interactions and damage level to cancer cells, and blocks division in target cells. In this study, a phosphaadamantane palladium complex ([Pd{(C,N)- (C12H8NH2)} (PTA) Cl], PTA = 1,3,5-Triaza-7-phosphaadamantane) ( 2 ) was synthesized via the reaction of biologically active PTA with binuclear palladacycles [Pd2{(C,N)-(C12H8NH2)}2(μ-Cl)2] ( 1 ). In vitro studies of the complex with DNA (calf-thymus) explored by UV–Vis, emission titration, circular dichroism and helix melting methods showed that the complex interacts with DNA via an intercalative mechanism. Furthermore, competitive binding studies using warfarin, digoxin and ibuprofen site markers containing definite binding sites revealed the binding of the complex to site I on bovine serum albumin. The in vitro release mechanism of the palladium complex exhibited a biphasic pattern characterized by an initial burst release followed by a slower sustained release. Ultimately, in vitro evaluation of cytotoxicity and cell death showed that the complexes were able to decrease the viability of human cancer cell lines (MCF-7 and Jurkat) in a dose-dependent manner, but lower decreases were observed in the viability of normal fibroblast cells ASF-4 at the dosages evaluated. Finally, the order of in vitro anticancer activities was found to be consistent with the DNA-binding affinities.  相似文献   
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