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31.
The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number. 相似文献
32.
Alam Ashraful Hariyanto Bambang Ullah Hayat Salin Krishna R. Datta Avishek 《SILICON》2021,13(9):3153-3162
Silicon - Silicon (Si) plays an important role in mitigating adverse effects of various biotic and abiotic stresses including drought. Polyhouse experiment was conducted to evaluate the effects of... 相似文献
33.
基于形状和颜色信息的烘焙产品的自动质量检测
Babar Khan,韩芳*,王直杰,Ather Iqbal
(东华大学 信息科学与技术学院,上海 201620)
创新点说明:
利用支持向量机和基于生物启发式HMAX模型的形状辨识器与RGB对抗颜色通道辨识器集成而形成一种有效的智能分类系统,并将其用于烘焙产品的质量检测。
研究目的:
本文要对烘焙产品进行更有效的质量检测,需要提出一种智能方法。
研究方法:
本文采用了支持向量机、基于生物启发式HMAX模型的形状辨识器与RGB对抗颜色通道辨识器集成,形成一种高级自动分类系统,对烘焙产品根据其形状和颜色(烘焙时间)进行对应分类。
结果:
利用本文方法对烘焙产品进行质量检测的结果与其它方法相比较,发现本文提出的基于生物启发的机器视觉系统运行更加精确和有效,同时发现采用One Versus One支持向量机和Directed Acyclic Graph支持向量机可以得到最大的分类精确率。本文方法对饼干形状和颜色的辨识分别达到了95%和100%的分类精确率。同时,算法稳定。
结论:
本文方法因其更加可靠和精确可用于代替现有的烘焙产品检测方法。
关键词:烘焙产品质量检测,计算机视觉,HMAX, 对抗颜色通道,RGB颜色辨识器,支持向量机
相似文献34.
Sardar Muhammad Bilal Atta ur Rehman Khan Samee Ullah Khan Sajjad A. Madani Babar Nazir Mazliza Othman 《Wireless Personal Communications》2014,77(4):2497-2515
Over the last few years, vehicular ad hoc networks (VANETs) have gained popularity for their interesting applications. To make efficient routing decisions, VANET routing protocols require road traffic density information for which they use density estimation schemes. This paper presents a distributed mechanism for road vehicular density estimation that considers multiple road factors, such as road length and junctions. Extensive simulations are carried out to analyze the effectiveness of the proposed technique. Simulation results suggested that, the proposed technique is more accurate compared to the existing technique. Moreover, it facilitate VANET routing protocols to increase packet delivery ratio and reduce end-to-end delay. 相似文献
35.
One of the most vociferous criticisms of the Internet has always been that it contributes to loneliness among its users. This study analyses results from the World Internet Project, comprised of representative samples from 13 countries (22,002 participants). Thus creating an exceptional international representative sample. In analyzing those results, we argue that in order to achieve a comprehensive understanding of the Internet’s influence over individuals’ social lives; it is essential to consider the different types of social connections that might be influenced by the Internet. We assess the influence of Internet use over social interactions in separate life domains (e.g. with family members; friends; colleagues). Our analysis confirms that Internet usage can actually enhance the social lives of its users. Qualifications to the research are discussed while highlighting the different life domains in which we found significant correlations between Internet usage and increased social interactions. 相似文献
36.
A statistical algorithm has been developed to compensate for the fixed-pattern noise associated with spatial nonuniformity and temporal drift in the response of focal-plane array infrared imaging systems. The algorithm uses initial scene data to generate initial estimates of the gain, the offset, and the variance of the additive electronic noise of each detector element. The algorithm then updates these parameters by use of subsequent frames and uses the updated parameters to restore the true image by use of a least-mean-square error finite-impulse-response filter. The algorithm is applied to infrared data, and the restored images compare favorably with those restored by use of a multiple-point calibration technique. 相似文献
37.
Rajaram N. Kulkarni V.V.S. Sanyasi Rao Ashok K. Babar 《Microelectronics Reliability》1990,30(6):1055-1059
A new empirical statistical distribution is reported, which describes the probability distribution of the unavailability QTOP for the top event of a fault tree. The distribution can be fitted using linear regression analysis. Investigations into the fit of the new distribution are reported, and as specific examples, two fault trees described in Reactor Safety Study are studied. The proposed distribution fits very well in both the cases, as shown by the χ2 test. For comparison, Johnson's SL and SB distributions, the log-normal distribution and the hybrid log-normal distribution are fitted to the same fault trees using the exact regression analysis method. Johnson's SB distribution cannot be fitted in the case of one of the fault trees as the necessary iterative process does not converge. For the other fault tree, the SB distribution fits very well. Johnson's SL distribution, the log-normal distribution and the hybrid log-normal distribution do not fit as well as the distribution proposed here and the χ2 test failed. Also, Johnson's distributions require the use of either an approximate method, involving a number of trials and errors, or non-linear regression analysis for fitting. The proposed distribution can, on the other hand, be fitted exactly using linear regression analysis and is, therefore, no more difficult to fit than the log-normal distribution. It is therefore concluded that the proposed distribution is most suited to describe the probability distribution of the unavailability for the top event of fault tree. Its suitability as a substitute for Johnson's distributions is also investigated. As specific examples, two statistical distributions in a text-book, for which fitting of Johnson's distributions has been suggested, are studied. The proposed distribution fits very well, as shown by the χ2 test. The proposed distribution is thus a good substitute for Johnson's SB distribution. 相似文献
38.
Investigating the joining capability of magnesium AZ31 alloy sheets and aluminium 1350 alloy sheets with the application of resistance spot welding was the objective of this study. The weld current values used in the welding process of Al–Mg sheets were 22, 23, 25, 27, 29, 31, and 33 kA. The studies examined the nugget geometries of joined specimens, recorded the scanning electron microscopy (SEM) images of the welded zone and the fracture surface, and recorded the energy-dispersive spectroscopy (EDS, semi-quantitative) analyses. The results of the experiment confirmed that nugget geometry was different for the Al and Mg sides. Tensile shear tests carried out on the welded joints determined their strength and failure mode. The increase in the weld current and duration resulted in an increase in the nugget size and the weld strength. According to observations, the tensile load bearing capacity (TLBC) increased up to 29 kA of the weld current value. It was also found that tearing during fracture occurred in two different ways. 相似文献
39.
In this study, unsteady boundary layer flow with Casson nanofluid within the sight of chemical reaction toward a stretching sheet has been analyzed mathematically. The fundamental motivation behind the present examination is to research the influence of different fluid parameters, in particular, Casson fluid , thermophoresis , magnetohydrodynamic , Brownian movement , Prandtl numberty, unsteadiness parameter , chemical reaction parameter , and Schmidt number on nanoparticle concentration, temperature, and velocity distribution. The shooting procedure has been adopted to solve transformed equations with the assistance of Runge–Kutta Fehlberg technique. The impact of different controlling fluid parameters on flow, heat, and mass transportation are depicted in tabular form and are shown graphically. Additionally, values of skin friction coefficient, Nusselt number, and Sherwood number are depicted via tables. Present consequences of the investigation for Nusselt number are related with existing results in writing by taking and where results are finding by utilization of MATLAB programming. Findings of current research help in controlling the rate of heat and mass aspects to make the desired quality of final product aiding manufacturing companies and industrial areas. 相似文献
40.
The influence of substrate temperature and nozzle-to-substrate distance(NSD) on the structural,morphological, optical and electrical properties of Sb:SnO2 thin films prepared by chemical spray pyrolysis has been analyzed.The structural,morphological,optical and electrical properties were characterized by using XRD,SEM, UV-visible spectrophotometry and Hall effect measurement techniques.It was seen that the films are polycrystalline, having a tetragonal crystal structure with strong orientation along the(200) reflection.The pyramidal crystallites formed due to coalescence were observed from SEM images.The values of highest conductivity,optical transmittance and figure of merit of about 1449(Ω·cm)-1,70%and 5.2×10-3□/Ω,respectively,were observed for a typical film deposited using optimal conditions(substrate temperature = 500℃and NSD = 30 cm). 相似文献