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61.
Ullah  Inam  Jian  Muwei  Hussain  Sumaira  Guo  Jie  Lian  Li  Yu  Hui  Shaheed  Kashif  Yin  Yilong 《Multimedia Tools and Applications》2021,80(5):7145-7165
Multimedia Tools and Applications - In recent years, the emergence of fully convolutional neural networks (FCNs) has delivered significant success in the field of saliency detection. Although the...  相似文献   
62.
The sintering behaviour and activation energy of Y2O3 partially stabilised ZrO2 and ZrO2–CNT (0.5 and 2 vol%) composites was determined using spark plasma sintering (SPS) under isothermal conditions. The sintering activation energy for the Y2O3 partially stabilised ZrO2 was found to be 456 kJ/mol. The addition of 2 vol% CNTs reduced the sintering activation energy to 172 kJ/mol. The significant reduction of the activation energy with the addition of only 2 vol% CNTs is attributed to the formation of a percolating network of CNTs providing a lower energy diffusion pathway. The sintering mechanism was found to be grain boundary diffusion for all samples suggesting that the presence of CNTs does not change the sintering mechanism but does lower the activation energy for the rate limiting step in the sintering process.  相似文献   
63.
Neural Computing and Applications - Parameter estimation of plane waves emitted by sources lying in Fraunhofer zone is one of the active areas of research for last few decades. In this study,...  相似文献   
64.
Carnobacterium maltaromaticum strains are widely found in food including fish, meat and some dairy products. Producing a malty/chocolate like aroma due to 3-methylbutanal from the catabolism of leucine is a general characteristic of this species. In this study, we investigated metabolic routes responsible for the biosynthesis of this flavor compound from the catabolism of leucine in C. maltaromaticum LMA 28, a strain isolated from mold ripened soft cheese. Depending on the lactic acid bacterium, leucine can be converted into 3-methylbutanal following two possible metabolic pathways: either directly by α-ketoacid decarboxylase (KADC) pathway or indirectly by α-ketoacid dehydrogenase (KADH) pathway. Both KADC (41.0±3.0 nmol/mg protein/min) and KADH (1.43±0.62 nmol/mg protein/min) activities were detected and determined in vitro in C. maltaromaticum LMA 28. C. maltaromaticum LMA 28 slightly reduced the production of 3-methylbutanal from leucine in the presence of a specific inhibitor of KADH enzyme complex, i.e. sodium meta-arsenite, suggesting that both pathways were involved in vivo in leucine catabolism. Moreover the presence of genes encoding aminotransferase, glutamate dehydrogenase, α-ketoacid decarboxylase, α-ketoacid dehydrogenase and aldehyde dehydrogenase was confirmed. C. maltaromaticum is then the first lactic acid bacterium in which presence of both metabolic routes responsible for the biosynthesis of 3-methylbutanal from leucine catabolism was confirmed in vitro and in vivo as well.  相似文献   
65.
Summary Residual stress induced deformations are a major cause of loss in tolerances in Solid Freeform Fabrication processes employing direct metal deposition. In this paper, a 2D finite element thermo-mechanical model is presented to predict the residual stress induced deformations with application to processes where material is added using a distributed, moving heat source. A sequentially coupled thermo-mechanical analysis is performed using a kinematic thermal model and plane strain structural model. Temperature dependent material properties are used with the material modeled as elastic perfectly plastic. An interpass cooling between successive depositions is employed in accordance to the requirement of experiment. The simulation results are compared with experimental data for successive sections along deposition and it is found that, with the exception of deposition center and plate edges, the two are in very good agreement. The error at plate edges can be as high as 45%, and the reason is that a 2D model cannot capture the effect of plate bolting accurately. A case of continuous deposition, without interpass cooling, has been compared with the base case of employing interpass cooling. It has been found that continuous deposition results in higher preheating of the substrate which consequently reduces the deformation.  相似文献   
66.
We report correlations between growth parameters, structure and microwave performance for YBa2Cu3O7-δ (YBCO) thin films. Two series of YBCO thin films were grown byin-situ laser ablation. The first series were deposited at 100 mTorr oxygen pressure with a laser fluence of 2.9 Joule/cm2, the second series were deposited at 600 mTorr of oxygen and a higher laser fluence of 5 Joule/cm2. Microwave performance of these films was evaluated using a 5.6 GHz resonator. In both series, we found that films with higherT c , narrower x-ray rocking curve width, and sharper electron channeling pattern tend to have higher microwave resonator Qs. Optimal film growth conditions were infered from this systematic study. Films grown at higher oxygen pressure have smoother surfaces and fewer second phases.  相似文献   
67.
68.
In the present study, we evaluate the importance of foliar epidermal micromorphological characteristics of Apocyanaceae for accurate identification and classification. The species were collected from the University of Peshawar's main campus in the spring season to observe its qualitative and quantitative features. The length and width of guard cells, stomatal pore and subsidiary cells, trichomes, and crypts on both sides of the leaf were examined. Many species were observed to be hypostomatic. Plumeria rubra, Raulfia serpentine, Thevetia peruviana, Trachelospermum lucidum, Alstonia scholaris, and Catharanthus roseus demonstrated hypostomatic leaves. Nearly all the investigated species had anisocytic type of stomata only or in combination with other types of stomata on the upper and lower epidermis. Carissa carandas had anomocytic, anisocytic, and cyclocytic type of stomata on the upper epidermis, and the lower epidermis showed variations in stomatal type, such as anomocytic, stephanocytic, brachyparacytic, and hemiparacytic. Nerium oleander had no specific shape of stomata but showed stomatal crypts in which the stomata were enclosed inside many trichomes. The taxonomic key based on stomatal types, epidermal cells, stomatal index value, and statistical analysis, along with the variations in the epidermal cells, shows the link between the selected plants species, which will provide a baseline for future anatomical studies. This study highlights many undocumented micromorphological characteristics. The anatomical characteristics observed in this study will be helpful for taxonomic identification and species delimitation of the family Apocynaceae.  相似文献   
69.
Neural Computing and Applications - Non-contiguous orthogonal frequency division multiplexing is considered as an auspicious scheme for the cognitive radio (CR) systems. It has the abilities such...  相似文献   
70.

A number of image encryption techniques have been proposed in recent years. These techniques use either spatial or transform domain image processing. A major challenge when designing an image encryption scheme is to conceal the pixel of the input image, especially when the image has a low texture region. Another problem is the encryption computational time. In this paper, these two issues are addressed. As the use of a single substitution box (S-box) to encrypt digital images does not work well for greater as well as a lower number of gray levels. To solve this problem, a new substitution technique using multiple S-boxes with dynamic substitution is proposed. In the second part of this paper, the proposed discrete wavelet transform based scheme is employed to reduce the encryption computational time. A number of parameters like correlation, entropy, energy, contrast, homogeneity, MSE and PSNR are used to analyze the quality of cipher images.

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