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91.
Although the grey forecasting models have been successfully utilized in many fields and demonstrated promising results, literatures show their performance still could be improved. The grey prediction theory is methodology and it is necessary to constantly present new models or algorithm based on the theory to improve its performance, prediction accuracy especially. For this purpose, this paper proposes a new prediction model called the deterministic grey dynamic model with convolution integral, abbreviated as DGDMC(1, n). Improvements upon the existing grey prediction model GM(1, n) are made to a large extent and the messages for a system can be inserted sufficiently. The major improvements include determining the unbiased estimates of the system parameters by the deterministic convergence scheme, introducing the first derivative of the 1-AGO data of each associated series into the DGDMC(1, n) model to strengthen the indicative significance and evaluating the modelling 1-AGO data of the predicted series by the convolution integral. The indirect measurement of the tensile strength of a material for a higher temperature is adpoted for demonstration. The results show that the accuracy of indirect measurement is higher by the DGDMC(1, n) model than by the existing GM(1, n) model. 相似文献
92.
We present a C-aperture encircled by a groove that makes possible the hybrid effect of coupling surface plasmon resonance to propagating waves. Compared to a single C aperture, the groove-encircled aperture can increase transmission by a factor of 2.45 in the near field and by a factor of 1.88 in the far field, showing good agreement with our theoretical calculation. 相似文献
93.
Y.-C. Lei W.-H. Tien J. Duncan M. Paul N. Ponchaut C. Mouton D. Dabiri T. R?sgen J. Hove 《Experiments in fluids》2012,53(5):1251-1268
A novel technique for particle tracking velocimetry is presented in this paper to overcome the issue of overlapping particle images encountered in the flows with high particle density or under volumetric illumination conditions. To achieve this goal, algorithms for particle identification and tracking are developed based on current methods and validated with both synthetic and experimental image sets. The results from synthetic image tests show that the particle identification algorithm is able to resolve overlapped particle images up to 50?% under noisy conditions, while keeping the root mean square peak location error under 0.07?pixels. The algorithm is also robust to the size changes up to a size ratio of 5. The tracking method developed from a classic computer vision matching algorithm is capable of capturing a velocity gradient up to 0.3 while maintaining the error under 0.2?pixels. Sensitivity tests were performed to describe the optimum conditions for the technique in terms of particle image density, particle image sizes and velocity gradients, also its sensitivity to errors of the PIV results that guide the tracking process. The comparison with other existing tracking techniques demonstrates that this technique is able to resolve more vectors out of a dense particle image field. 相似文献
94.
Nguyen Van Hung Cu Sy Thang Nguyen Ba Duc Dinh Quoc Vuong Tong Sy Tien 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(12):256
Thermodynamic properties, anharmonic effects and structural determination of fcc crystals have been studied based on the theoretical and experimental Debye–Waller factors presented in terms of cumulant expansion up to the third order, thermal expansion coefficient, X-ray absorption fine structure (XAFS) spectra and their Fourier transform magnitudes. The advances in these studies are performed by the further development of the anharmonic correlated Einstein model primary only for approximating three first XAFS cumulants into the method using that all the considered theoretical and experimental XAFS parameters have been provided based on only the calculated and measured second cumulants. The obtained cumulants describe the anharmonic effects in XAFS contributing to the accurate structural determination. Numerical results for Cu are found to be in good agreement with the experimental values extracted by using the present advanced method and with those obtained by the other measurements. 相似文献
95.
The toxicity and antitumour effect of the ethanol extract of Selaginella tamariscina (STE), a plant widely used in folk medicine, were examined in a mice model. In the single-dose acute toxicity test, an oral administration of 10,000?mg?kg(-1) STE did not cause any lethality. The sub-acute toxicity study showed that the treatment by 250,?1000 and 3000?mg?kg(-1?)day(-1) for 30 continuous days did neither alter the body weights nor the haematological parameters in BALB/c mice. The anticancer effect of STE was evaluated in BALB/c mice inoculated with Lewis lung carcinoma cells. Oral administration of STE could not prevent the tumour formation but provided strong inhibition of tumour growth. 相似文献
96.
Tien Thanh Nguyen Huu Hao Ngo Wenshan Guo Jianxin Li Andrzej Listowski 《Applied biochemistry and biotechnology》2012,167(6):1678-1687
The performance of a novel sponge-submerged membrane bioreactor (SSMBR) was evaluated to treat primary treated sewage effluent at three different activated sludge concentrations. Polyurethane sponge cubes with size of 1?×?1?×?1?cm were used as attached growth media in the bioreactor. The results indicated the successful removal of organic carbon and phosphorous with the efficiency higher than 98% at all conditions. Acclimatised sponge MBR showed about 5% better ammonia nitrogen removal at 5 and 10?g/L sludge concentration as compared to the new sponge system. The respiration test revealed that the specific oxygen uptake rate was around 1.0?C3.5?mgO2/gVSS.h and likely more stable at 10?g/L sludge concentration. The sludge volume index of less than 100?mL/g during the operation indicated the good settling property of the sludge. The low mixed liquor suspended solid increase indicated that SSMBR could control the sludge production. This SSMBR was also successful in reducing membrane fouling with significant lower transmembrane pressure (e.g. only 0.5?kPa/day) compared to the conventional MBR system. Further study will be conducted to optimise other operating conditions. 相似文献
97.
E. V. Charnaya M. K. Lee C. Tien V. N. Pak D. V. Formus A. L. Pirozerskii A. I. Nedbai E. V. Ubyivovk S. V. Baryshnikov L. J. Chang 《Physics of the Solid State》2012,54(9):1891-1895
The magnetization of the porous glass nanocomposite with CuO nanoparticles embedded in the pores has been studied in the temperature range from 1.8 to 350 K for different pore fillings. It has been shown that the magnetic properties of these nanocomposites depend significantly on pore filling. It has been found that, in the low-temperature range for the nanocomposite with a pore filling of 55% and for pressed CuO, the ZFC and FC susceptibilities diverge, a feature which has been almost absent in the nanocomposite with 21% filling. It has been demonstrated that the kink in the temperature dependence of magnetization, which corresponds to the paramagnetic-multiferroic phase transition, does not shift in the sample with a larger pore filling as compared to that observed in the bulk sample. 相似文献
98.
Defocusing digital particle image velocimetry (DDPIV), as a true three-dimensional (3D) measurement technique, allows for
the measurement of 3D velocities within a volume. Initially designed using a single CCD and 3-pinhole mask (Willert and Gharib
in Exp Fluids 12:353–358, 1992), it has evolved into a multi-camera system in order to overcome the limitations of image saturation due to multiple exposures
of each particle. In order to still use a single camera and overcome this limitation, we have modified the original single
CCD implementation by placing different color filters over each pinhole, thus color-coding each pinhole exposure, and using
a 3-CCD color camera for image acquisition. Due to the pinhole mask, there exists the problem of a significant lack of illumination
in a conventional lighting setup, which we have solved by backlighting the field-of-view and seeding the flow with black particles.
This produces images with a white background superimposed with colored triple exposures of each particle. A color space linear
transformation is used to allow for accurate identification of each pinhole exposure when the color filters’ spectrum does
not match those of the 3-CCD color camera. Because the imaging is performed with a multi-element lens instead of a single-element
lens, an effective pinhole separation, d
e, is defined when using a pinhole mask within a multi-element lens. Calibration results of the system with and without fluid
are performed and compared, and a correction of the effective pinhole separation, d
e, due to refraction through multiple surfaces is proposed. Uncertainty analyses are also performed, and the technique is successfully
applied to a buoyancy-driven flow, where a 3D velocity field is extracted. 相似文献
99.
Dr. Daniela Mélanie Delannoy López Dr. Dong Tien Tran Dr. Guillaume Viault Dr. Sofiane Dairi Dr. Philippe Alexandre Peixoto Yoan Capello Laëtitia Minder Prof. Laurent Pouységu Dr. Elisabeth Génot Dr. Carmelo Di Primo Dr. Denis Deffieux Prof. Stéphane Quideau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(17):5498-5508
A selection of bioactive polyphenols of different structural classes, such as the ellagitannins vescalagin and vescalin, the flavanoids catechin, epicatechin, epigallocatechin gallate (EGCG), and procyanidin B2, and the stilbenoids resveratrol and piceatannol, were chemically modified to bear a biotin unit for enabling their immobilization on streptavidin-coated sensor chips. These sensor chips were used to evaluate in real time by surface plasmon resonance (SPR) the interactions of three different surface-bound polyphenolic ligands per sensor chip with various protein analytes, including human DNA topoisomerase IIα, flavonoid leucoanthocyanidin dioxygenase, B-cell lymphoma 2 apoptosis regulator protein, and bovine serum albumin. The types and levels of SPR responses unveiled major differences in the association, or lack thereof, and dissociation between a given protein analyte and different polyphenolic ligands. Thus, this multi-analysis SPR technique is a valuable methodology to rapidly screen and qualitatively compare various polyphenol–protein interactions. 相似文献
100.
Dung Nguyen Tien Thanh Do Minh Huong Nguyen Thi Thuy Phan Thi Hoan Nguyen Thi Thanh Dinh Thi Mai Van Trang Nguyen Son Ninh The 《Structural chemistry》2020,31(6):2435-2450
Structural Chemistry - Quinolone and isoquinolone alkaloids, which were found in the plant kingdom, are now potential antioxidants. In this case study, a quantum calculated procedure utilizing the... 相似文献