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61.
ON ASYMPTOTIC NORMALITY OF PARAMETERS IN LINEAR EV MODEL   总被引:2,自引:0,他引:2  
This paper studies the parameter estimation of one dimensional linear errors-in-variables (EV) models in the case that replicated observations are available in some experimental points. Asymptotic normality is established under mild conditions, and the parameters entering the asymptotic variance are consistently estimated to render the result useable in construction of large-sample confidence regions.  相似文献   
62.
Progress in the studies of “solar activity and its geo-space Effects”   总被引:3,自引:0,他引:3  
Estimators are presented for the coefficients of the polynomial errors-in-variables (EV) model when replicated observations are taken at some experimental points. These estimators are shown to be strongly consistent under mild conditions.  相似文献   
63.
Summary A general analysis of the characteristics of a resonant transducer for gravitational-wave antennas whose resonator has a general mode of vibration has been made using a Lagrangian formalism. The method has been applied to investigate the characteristics of the resonant capacitive transducer developed at the University of Rome and mounted on the cryogenic gravitational-wave antenna built at CERN, finding results in good agreement with the experimental behaviour.
Riassunto Si usa il formalismo lagrangiano per svolgere un'analisi delle caratteristiche di un trasduttore risonante per antenne gravitazionali nel caso generale in cui il risuonatore utilizzato abbia un modo di vibrazione di forma qualunque. Il metodo è applicato allo studio delle caratteristiche del trasduttore risonante capacitivo sviluppato alla I Università di Roma e montato sull'antenna gravitazionale criogenica realizzata al CERN, trovando risultati in buon accordo con i valori sperimentali.

Резюме Используя Лагранжев формализм, проводится обший анализ характеристик резонансного датчика для антенн гравитационных волх. Предложенный метод применяется для исследования характеристик резонансного емкостного датчика, разработанного в Римском Университете и смонтированного на криогенной антенне гравитационных волн в ЦЕРНе. Полученные результаты хорошо согласуются с экспериментальными данными.
  相似文献   
64.
Solid cast films with polydomain textures were prepared on a glass substrate with transparent interdigitated electrodes from an isotropic aqueous solution of hydroxypropyl cellulose via its liquid crystalline phase under the sinusoidal electric field with small amplitude and frequency of 0.05 V µm-1 and 105 Hz, respectively. The process was monitored using microdielectrometry as well as polarised optical microscopy. The apparent dielectric constant εr' and loss factor εr' sensitively changed with time depending on the process conditions. On the other hand, the logarithmic relation between εr' and εr' showed a single curve, when they were normalised by an effective portion of the electrostatic energy density estimated using each solid-film thickness. The conversion to the solid film was estimated during the process based on the concentration dependences of εr' and εr'. Characteristic times were reported for the onset of the biphasic phase, fully developed cholesteric phase and termination of the process.  相似文献   
65.
A linear model observed in a spatial domain is considered. Consistency and asymptotic normality of the least squares estimator is proved when the observations become dense in a sequence of increasing domains and the error terms are weakly dependent. Similar statements are obtained for the linear errors-in-variables model. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
66.
We use the new gamma-ray bursts (GRBs) data, combined with the baryon acoustic oscillation (BAO) observation from the spectroscopic Sloan digital sky survey (SDSS) data release, the newly obtained A   parameter at z=0.6z=0.6 from the WiggleZ dark energy survey, the cosmic microwave background (CMB) observations from the 7-year Wilkinson microwave anisotropy probe (WMAP7) results, and the type Ia supernovae (SNeIa) from Union2 set, to constrain a phenomenological model describing possible interactions between dark energy and dark matter, which was proposed to alleviate the coincidence problem of the standard ΛCDM model. By using the Markov chain Monte Carlo (MCMC) method, we obtain the marginalized 1σ   constraints Ωm=0.2886±0.0135Ωm=0.2886±0.0135, rm=−0.0047±0.0046rm=0.0047±0.0046, and wX=−1.0658±0.0564wX=1.0658±0.0564. We also consider other combinations of these data for comparison. These results show that: (1) the energy of dark matter is slightly transferring to that of dark energy; (2) even though the GRBs + BAO + CMB data present less stringent constraints than SNe + BAO + CMB data do, the GRBs can help eliminate the degeneracies among parameters.  相似文献   
67.
Despite a century-long effort, a proper energy-stress tensor of the gravitational field, could not have been discovered. Furthermore, it has been discovered recently that the standard formulation of the energy-stress tensor of matter, suffers from various inconsistencies and paradoxes, concluding that the tensor is not consistent with the geometric formulation of gravitation [Astrophys. Space Sci., 2009, 321: 151; Astrophys. Space Sei., 2012, 340: 373]. This perhaps hints that a consistent theory of gravitation should not have any bearing on the energy-stress tensor. It is shown here that the so-called "vacuum" field equations Rik = 0 do not represent an empty spacetime, and the energy, momenta and angular momenta of the gravitational and the matter fields are revealed through the geometry, without including any formulation thereof in the field equations. Though, this novel discovery appears baffling and orthogonal to the usual understanding, is consistent with the observations at all scales, without requiring the Moreover, the resulting theory circumvents the besides explaining some unexplained puzzles. hypothetical dark matter, dark energy or inflation long-standing problems of the standard cosmology  相似文献   
68.
We investigate the constraints on total neutrino mass in the scenario of vacuum energy interacting with cold dark matter. We focus on two typical interaction forms, i.e., Q=βHρc and Q=βHρ. To avoid the occurrence of large-scale instability in interacting dark energy cosmology, we adopt the parameterized post-Friedmann approach to calculate the perturbation evolution of dark energy. We employ observational data, including the Planck cosmic microwave background temperature and polarization data, baryon acoustic oscillation data, a JLA sample of type Ia supernovae observation, direct measurement of the Hubble constant, and redshift space distortion data. We find that, compared with those in the ∧CDM model, much looser constraints on ∑mν are obtained in the Q=βHρc model, whereas slightly tighter constraints are obtained in the Q=βHρ model. Consideration of the possible mass hierarchies of neutrinos reveals that the smallest upper limit of ∑mν appears in the degenerate hierarchy case. By comparing the values of χmin2, we find that the normal hierarchy case is favored over the inverted one. In particular, we find that the difference △χmin2 ≡ χIH; min2NH; min2 > 2 in the Q=βHρc model. In addition, we find that β=0 is consistent with the current observations in the Q=βHρc model, and β < 0 is favored at more than the 1σ level in the Q=βHρ model.  相似文献   
69.
The results of experimental observations and mathematical modeling of corona formation on the tips of grounded rods are presented as a function of their tip height, curvature radius, the magnitude and polarity of the applied electric field producing corona. The investigations demonstrate that corona current depends on the active volume of zone in which electric field strength exceeds the breakdown criteria for air. The mathematical model was verified with the experimental data, enabling dependence of corona current on rod tip height, tip radius and applied electric field strength to be quantified with the need for a plethora of experiments.  相似文献   
70.
Atmospheric observations from space often result in spectral data of large dimensions. To allow an optimal inversion of the observed spectra it can be necessary to map the data into a space of smaller dimension. Here several data reduction techniques based on eigenvector expansions of the spectral space are compared. The comparison is done by inverting simulated observations from a microwave limb sounder, the Odin-SMR. For the examples tested, reductions exceeding two orders of magnitude with no negative influence on the retrieval performance are demonstrated. The techniques compared include a novel method developed especially for atmospheric inversions, based on the weighting functions of the variables to be retrieved. The new method shows an excellent performance in practical tests and is both computationally more effective and more flexible than the standard Hotelling transformation.  相似文献   
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