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排序方式: 共有2396条查询结果,搜索用时 46 毫秒
61.
A. S. Ibraheam Y. Al-Douri J. M. S. Al-Fhdawi Hamid S. AL-Jumaili K. D. Verma U. Hashim R. M. Ayub A. Rahim Ruslinda M. K. Md Arshad A. H. Reshak S. B. Abd Hamid 《Microsystem Technologies》2016,22(12):2893-2900
The Cu2Zn1?xCdxSnS4 quinternary alloy nanostructures with different Cd contents were grown using spin coating technique on porous silicon (63.93 %) substrate. The structural properties of Cu2Zn1?xCdxSnS4/PS were investigated by X-ray diffraction and field emission-scanning electron microscope (FE-SEM). The optical properties studied through photoluminescence technique, indicated that the band gap is shifted as Cd content increases from 1.84 eV at x = 0 to 1.76 eV at x = 1. The electrical characterization of the Ag/n-PS/Cu2Zn1?xCdxSnS4/Ag diode through current to voltage (I–V) characterization shows the highest photo-response of (value if any) at Cu2Zn0.4Cd0.6SnS4 composition. 相似文献
62.
Hafiz Shehzad Ahmed Hong-Dong Zhao Munawar Hussain Jing Wang 《Pattern Recognition and Image Analysis》2017,27(4):804-809
Image processing algorithm is implemented to detect the grain boundary of the crystal using (SEM) Scanning Electron Microscopy. This paper presents a method for edge-detection in color image based on Sobel, Canny operator’s algorithm and discrete wavelet transform. The performance of these methods is effective and faster. Filtering is another approach to clear the noise of an image. Scanning Electron Microscopy (SEM) used to inspect semiconductor materials and devices for several decades, continues to increase in importance. Removal of noise is an important step in the image restoration process, but de-noising of the image has remained a challenging problem in recent research associated with image process. De-noising is used to remove the noise from corrupted images, while retaining the edges and other detailed features too are an essential part of de-noising. 相似文献
63.
Bowsher JG Hussain A Williams PA Shelton JC 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2006,220(2):279-287
This study investigated changes in metal-on-metal (MOM) hip wear and wear particle characteristics arising from a more aggressive patient activity level compared with normal walking. The test hypothesis was that 'severe'-gait conditions will change wear, wear particle sizes, and morphology owing to a decline in joint lubrication. Four carbon MOM hip bearings 40 mm high were subjected to normal-walking and fast-jogging simulations in an orbital hip joint simulator with 25 per cent alpha-calf serum as a lubricant. Co-Cr-Mo wear particles were extracted using an enzymatic method, and prolate ellipsoid equations were used to estimate particle volume and surface area. Fast-jogging simulations generated a sevenfold increase in volumetric wear, a 33 per cent increase in mean wear particle size, and a threefold increase in the number of larger (needle) particles compared with walking. This resulted in a twentyfold increase in total wear particle surface area per 10(6) cycles compared with walking, thereby confirming our hypothesis. The clinical significance of this result suggests that highly active MOM patients may exhibit greater ion release than less active patients. 相似文献
64.
65.
Conti-Ramsden MG Asghar HM Hussain SN Roberts EP Brown NW 《Water science and technology》2012,66(9):1849-1855
The removal of the mercaptan, 1-methyl-1-propanethiol, from aqueous solutions using a non-porous, electrically conducting carbon-based adsorbent (Nyex 1000) was investigated. The adsorption process was found to be rapid (equilibrium capacity achieved within 5 minutes) with low adsorptive capacity (of the order of 0.4 mg g(-1)) when compared with activated carbon. Electrochemical regeneration of the Nyex 1000 in a simple divided electrochemical cell within a sequential batch treatment unit restored 100% of the adsorbent's adsorptive capacity using treatment times as low as 20 minutes by passing a current of 0.5 A. The sorptive characteristics of a Nyex-water slurry were also modelled and investigated both in a bubble column and in a continuous adsorption-regeneration treatment system. It was demonstrated that the continuous removal-destruction system could achieve a step reduction in challenge gas concentration of approximately 75% for a period of 35 minutes with a current of 5 Amps. This was attributed to mass transfer enhanced by a combination of adsorption and chemical reaction with free chlorine species generated in the electrochemical process. 相似文献
66.
Hussain Shareef Azah Mohamed Saifunizam Abd. Khalid Mohd Wazir Mustafa 《中南工业大学学报(英文版)》2012,19(1):179-186
A multivariable regression (MVR) approach is proposed to identify the real power transfer between generators and loads. Based
on solved load flow results, it first uses modified nodal equation method (MNE) to determine real power contribution from
each generator to loads. Then, the results of MNE method and load flow information are utilized to determine suitable regression
coefficients using MVR model to estimate the power transfer. The 25-bus equivalent system of south Malaysia is utilized as
a test system to illustrate the effectiveness of the MVR output compared to that of the MNE method. The error of the estimate
of MVR method ranges from 0.001 4 to 0.007 9. Furthermore, when compared to MNE method, MVR method computes generator contribution
to loads within 26.40 ms whereas the MNE method takes 360 ms for the calculation of same real power transfer allocation. Therefore,
MVR method is more suitable for real time power transfer allocation. 相似文献
67.
Omar K. Hussain Tharam Dillon Farookh Khadeer Hussain Elizabeth Chang 《Journal of Intelligent Manufacturing》2012,23(6):2069-2084
In Demand-driven Production with Just-in-Time inputs, there are several sources of uncertainty which impact on the manufacturer??s ability to meet the required customer??s demand within the given time frame. This can result in a loss of revenue and customers, which will have undesirable impacts on the financial aspects and on the viability of the manufacturer. Hence, a key concern for manufacturers in just-in-time production is to determine whether they can meet a specific level of demand within a given time frame, to meet the customers?? orders and also to achieve the required revenue target for that period of time. In this paper, we propose a methodology by which a manufacturer can ascertain the probability of not meeting the required demand within a given period by considering the uncertainties in the availability of production units and raw materials, and the loss of financial revenue that it would experience as a result. 相似文献
68.
This paper reports on the affect of lead content on the absorption and emission spectra of the Ho3+ ion doped lead-zinc-borate glasses in the composition (mol%) of (20 − x)PbO-20ZnO-(59 + x)B2O3-1.0Ho2O3 where x = 0, 5,10,15 of PbO content with λexc = 405 nm. The experimental absorption band energies have satisfactorily been correlated with the theoretical results with an r.m.s deviation of zero with the following correction factors obtained by a least square fit analysis: ΔE1 = 348.495936 cm− 1, ΔE2 = 1.436043 cm− 1, ΔE3 = 46.481575 cm− 1, Δξ4f = − 28.512979 cm− 1, Δα = 55.508936 cm− 1, Δβ = − 1394.339908 cm− 1 and Δγ = 1208.424336 cm− 1. By applying the Judd-Ofelt intensity parameter Ω2 has been found to be linearly decreasing with the PbO content from 5 to 10 mol% and then increasing. And also radiative (A, AT, β, τr) characteristic factors of the luminescent transitions (5I8 ← 5F3,4,5 and 5S2) of the glasses have been evaluated. Stimulated emission cross-sections (σpE) of the measured emission transitions of holmium glasses have also been computed. 相似文献
69.
Genetic algorithms are applied to an important, but little investigated, network design problem, that of reconfiguring the topology and link capacities of an operational network to adapt to changes in its operating conditions. These conditions include: which nodes and links are unavailable; the traffic patterns; and the quality of service (QoS) requirements and priorities of different users and applications. Dynamic reconfiguration is possible in networks that contain links whose endpoints can be easily changed, such as satellite channels, terrestrial wireless connections, and certain types of optical connections. We report preliminary results that demonstrate the feasibility of performing genetic search quickly enough for online adaptation. 相似文献
70.
Asif Hussain Khoja Arslan Mazhar Faisal Saleem Muhammad Taqi Mehran Salman Raza Naqvi Mustafa Anwar Sehar Shakir Nor Aishah Saidina Amin Muhammad Bilal Sajid 《International Journal of Hydrogen Energy》2021,46(29):15367-15388
The catalyst has a significant role in gas processing applications such as reforming technologies for H2 and syngas production. The stable catalyst is requisite for any industrial catalysis application to make it commercially viable. Several methods are employed to synthesize the catalysts. However, there is still a challenge to achieve a controlled morphology and pure catalyst which majorly influences the catalytic activity in reforming applications. The conventional methods are expansive, and the removal of the impurities are major challenges. Nevertheless, it is not straightforward to achieve the desired structure and stability. Therefore, significant interest has been developed on the advanced techniques to take control of the physicochemical properties of the catalyst through non-thermal plasma (NTP) techniques. In this review, the systematic evolution of the catalyst synthesis using NTP technique is elucidated. The emerging DBD plasma to synthesized and effective surface treatment is reviewed. DBD plasma synthesized catalyst performance in reforming application for H2 and syngas production is summarised. Furthermore, the status of DBD plasma for catalyst synthesis and proposed future avenues to design environmentally suitable and cost-effective synthesis techniques are discussed. 相似文献