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101.
Matiur Rahman 《Applied Mathematical Modelling》1981,5(2):109-121
The numerical development of resonance of a harbour of arbitrary shape and depth is studied. The harbour is subdivided into subregions according to the variations of bottom topography such that each subregion is of uniform depth. The Helmholtz wave equation is formulated in each subregion as an integral equation of the Green's theorem. The solution to the entire harbour basin is obtained by a matching procedure at the subregion boundaries. Here, we consider a harbour with basins of constant depths connected in series successively to accommodate a more complicated harbour geometry. An application of this study is made to Kincardine harbour with five basins connected in series successively. 相似文献
102.
Rahman M Younis 《Journal of Functional Analysis》1980,39(1):16-22
An interpolation result related to the Hardy space H∞(m) associated with a logmodular algebra A is presented, where m is the representing measure for some γ?M (A). The above result is used to answer a question rasied in [6]. 相似文献
103.
The theory of double resonance through the continuum is considered in view of incorporating statistical effects. After resolving the relevant Schrödi 相似文献
104.
105.
In this paper we study the local behaviour of a trigonometric polynomial around any of its zeros in terms of its estimated values at an adequate number of freely chosen points in . The freedom in the choice of sample points makes our results particularly convenient for numerical calculations. Analogous results for polynomials of the form are also proved.
106.
H.?AhmadEmail author M.?A.?J.?Miah M.?S.?Pervin M.?M.?Rahman 《Colloid and polymer science》2003,281(9):897-901
Modification of surface properties of polymer particles suitable for biomedical application has been done by incorporating acrylic acid (AA) as a hydrophilic component. First, submicron-sized poly(methyl methacrylate) seed particles were prepared by soap-free emulsion polymerization. Then, seeded emulsion copolymerizations were carried out with varying proportions of AA and methyl methacrylate (MMA). MMA was used as a comonomer to prevent the dissolution of AA from the polymer particles. The adsorption behaviors of different biomolecules indicate that the surface of the composite polymer particles is sufficiently hydrophilic, particularly at higher AA content. Specific activities of adsorbed trypsin on the composite polymer particles were also comparatively high compared to free trypsin, which suggests that the adsorbed trypsin undergoes only slight conformational change owing to the interaction with the surface of particles. 相似文献
107.
D. P. Dryanov M. A. Qazi Q. I. Rahman 《Proceedings of the American Mathematical Society》2003,131(9):2741-2751
Extensions of two classical results about polynomials, one due to W. Markov and the other due to Duffin and Schaeffer, are obtained in this paper. An interesting result of S. Bernstein, which went unnoticed until it was rediscovered by P. Erdos, years later, is also generalized. Our results are especially amenable to numerical calculations, and may, therefore, be of some practical importance.
108.
T.S. Rahman S. Stolbov F. Mehmood 《Applied Physics A: Materials Science & Processing》2007,87(3):367-374
We present results of ab initio electronic structure calculations based on density functional theory which show in detail
several effects of alkali adsorption on metal substrates and on molecules coadsorbed on the substrate. First, calculations
of the isoelectronic reactivity index demonstrate a dramatic enhancement of the electronic polarizability of the metal substrate
extending it several angstroms into the vacuum. This phenomenon is traceable to an unusual feature induced in the surface
potential on alkali adsorption. The effect appears to be general and helps explain the observed substantial decrease in the
vibrational frequency of molecules such as CO and O2 when co-adsorbed with alkalis on metal surfaces. Next, for the oxidation of CO on Pd(111), we illustrate the changes in the
reaction pathway and activation energy barriers induced in the presence of coadsorbed K.
PACS 73.20.-r; 71.15.-m 相似文献
109.
In this paper we presented a method, which will allow multiple parameter control of the 3-dB bandwidth, center notch wavelength and attenuation level in a fiber-based acousto-optic tunable filter (AOTF). The method basically involves the variation of the interaction length, RF frequency and RF power on a single-fiber device to achieve multiple parameters tuning of the optical filter. The acousto-optic (AO) interaction inside a single-mode fiber (SMF) was studied theoretically and experimentally. 相似文献
110.
Yuhei Horio Md. Mijanur Rahman Yurei Imai Yoshihiro Hishikawa Takashi Minemoto 《Current Applied Physics》2017,17(10):1341-1346
The output energy of photovoltaic (PV) modules is influenced by the spectral irradiance distribution of the solar spectrum under outdoor conditions. To rate the precise output energy of PV modules, the correction of short circuit current (ISC) based on actual environmental conditions is needed, because ISC significantly depends on the shape of the spectral irradiance distribution. The average photon energy (APE) is a zero-dimensional index for spectral irradiance distribution, and APE value uniquely describes the shape of a solar spectrum. Thus, APE has an impact on ISC of PV modules. In this contribution, the relationship between APE coefficient and ISC of the multi-crystalline silicon, single-crystalline silicon, heterojunction intrinsic thin-layer, back contact, copper indium selenide and cadmium telluride PV modules has explored. It is revealed that APE value changes the ISC of PV modules which appeared to have immense possibilities of ISC correction using APE coefficient. This new approach can be very effective for precise rating the output energy of PV modules under actual outdoor conditions. 相似文献