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51.
Agarwal Rohit Jalal Anand Singh Arya K. V. 《Multimedia Tools and Applications》2020,79(19-20):13621-13645
Multimedia Tools and Applications - Biometric authentication can establish a person’s identity from their exclusive features. In general, biometric authentication can vulnerable to spoofing... 相似文献
52.
Wireless Personal Communications - Biometric traits are frequently used by security agencies for automatic recognition of a person. There are numerous biometric traits used for person... 相似文献
53.
Kashif Saleem Mehmet A. Orgun Jalal Al-Muhtadi Joel J. P. C. Rodrigues Mohammed Zakariah 《Behaviour & Information Technology》2017,36(7):687-698
The current century has brought an unimaginable growth in information and communications technology (ICT) and needs of enormous computing. The advancements in computer hardware and software particularly helped fuel the requirements of human beings, and revolutionized the smart products as an outcome. The advent of wearable devices from their development till successful materialisation has only taken less than a quarter of a century. The huge benefits of these smart wearable technologies cannot be fully enjoyed until and unless the reliability of a complete system is ensured. The reliability can be increased by the consistent advancements in hardware and software in parallel. User expectations actually are the challenges that keep the advancements alive while improving at an unmatchable pace. The future of wearable and other smart devices depends on whether they can provide a timely solution that is reliable, richer in resources, smaller in size, and cheaper in price. This paper addresses the threats and opportunities in the development and the acceptance of immersive and wearable technologies. The hardware and software challenges for the purpose of development are discussed to demonstrate the bottlenecks of the current technologies and the limitations that impose those bottlenecks. For the purpose of adoption, social and commercial challenges related to innovation and acceptability are discussed. The paper proposes guidelines that are expected to be applicable in several considerable applications of wearable technologies, for example, social networks, healthcare, and banking. 相似文献
54.
The effect of carboxy-methyl cellulose (CMC) coating on mass transfer process during osmotic dehydration of apple slices and its effect on salt absorption were investigated. The study was conducted using four concentrations of CMC (0.5, 1, 1.5, and 3%) and nine osmotic solutions comprising of glucose syrup (30, 40, and 50%) and salt (2, 4, and 6%). Sample contact time with the hypertonic solution was 15, 30, 60, 120, 180, 240, and 360 min. Both coated and uncoated samples were evaluated in terms of water loss (WL), solids gain (SG), WL/SG ratio, and salt absorption. Optimal condition was obtained when the CMC concentration of 1% was used with hypertonic solution comprising of 50% glucose syrup and 2% salt. 相似文献
55.
Nitrogen balance in dryland agroecosystem in response to tillage,crop rotation,and cultural practice 总被引:1,自引:0,他引:1
Upendra M. Sainju Andrew W. Lenssen Brett L. Allen William B. Stevens Jalal D. Jabro 《Nutrient Cycling in Agroecosystems》2018,110(3):467-483
Accounting of N inputs and outputs and N retention in the soil provides N balance that measures agroecosystem performance and environmental sustainability. Because of the complexity of measurements of some N inputs and outputs, studies on N balance in long-term experiments are scanty. We examined the effect of 8 years of tillage, crop rotation, and cultural practice on N balance based on N inputs and outputs and soil N sequestration rate under dryland cropping systems in the northern Great Plains, USA. Tillage systems were no-tillage (NT) and conventional tillage (CT) and crop rotations were continuous spring wheat (Triticum aestivum L.) (CW), spring wheat–pea (Pisum sativum L.) (W–P), spring wheat–barley (Hordeum vulgaris L.) hay–pea (W–B–P), and spring wheat–barley hay–corn (Zea mays L.)–pea (W–B–C–P). Cultural practices were traditional (conventional seed rates and plant spacing, conventional planting date, broadcast N fertilization, and reduced stubble height) and improved (variable seed rates and plant spacing, delayed planting, banded N fertilization, and increased stubble height). Total N input due to N fertilization, pea N fixation, atmospheric N deposition, crop seed N, and nonsymbiotic N fixation was greater with W–B–C–P than CW, regardless of tillage and cultural practices. Total N output due to aboveground biomass N removal and N losses due to denitrification, volatilization, plant senescence, N leaching, gaseous N (NOx) emissions, and surface runoff were not different among treatments. Nitrogen sequestration rate at 0–20 cm from 2004 to 2011 varied from 29 kg N ha?1 year?1 in CT with W–P to 89 kg N ha?1 year?1 in NT with W–P. Nitrogen balance varied from ? 39 kg N ha?1 year?1 in NT with CW and the improved practice to 41 kg N ha?1 year?1 in CT with W–P and the traditional practice. Because of legume N fixation and increased soil N sequestration rate, diversified crop rotations reduced external N inputs and increased aboveground biomass N removal, N flow, and N balance compared with monocropping, especially in the CT system. As a result, diversified legume–nonlegume crop rotation not only reduced the cost of N fertilization by reducing N fertilization rate, but also can be productive by increasing N uptake and N surplus and environmentally sustainable by reducing N losses compared with nonlegume monocropping, regardless of cultural practices in dryland agroecosystems. 相似文献
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57.
Stability of gravitationally unstable double diffusive transient boundary layers with variable viscosity in porous media 下载免费PDF全文
Nasser Sabet Hassan Hassanzadeh Jalal Abedi 《American Institute of Chemical Engineers》2017,63(6):2471-2482
We study the double diffusive convection (DDC) in porous media through linear stability analysis (LSA) and direct numerical simulations (DNS). Unlike the previous studies that assume static solutal or thermal fields, the developed model is able to capture the transient behavior of both fields. We show that under the assumption of static field, the role of Lewis number cannot be distinguished. Under transient fields, we conclude that higher Lewis numbers result in earlier instability of the boundary layers. Moreover, the effect of viscosity contrast is explained in terms of the mobility of the boundary layer. The DNS results confirm the validity of LSA predictions. We also obtain the critical Rayleigh number and show that in the presence of viscosity contrast, it can be much smaller than the conventional limit of 4π2. This study provides a better understanding of the transient nature of DDC in the presence of viscosity variations. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2471–2482, 2017 相似文献
58.
A simple, highly sensitive and reliable microfunnel magnetic stirring-assisted dispersive liquid–liquid microextraction method (MF-MSA-DLLME) was developed based on the derivatization of mutagen X in aqueous samples and determined using gas chromatography with electron capture (GC-ECD). The effects of different variables on the extraction efficiency were investigated and optimized. The calibration curve showed good linearity in the concentration range of 0.05–400 μgL?1 (r2 = 0.998) and precision (RSD = 5.0%). Under optimum conditions, the limit of detection (LOD) and the limit of quantification in drinking water were 0.015 and 0.05 µg L?1, respectively. The developed method was successfully applied for the determination of six Mutagen X (MX) in real samples. 相似文献
59.
60.
Walaaeldin Ghadiry Jalal Habibi Amir G. Aghdam Youmin Zhang 《Journal of Intelligent and Robotic Systems》2017,87(3-4):699-710
In this paper, two new formulations are presented for trajectory optimization in the patrolling problem. It is assumed that the starting depot is not prespecified; an assumption that distinguishes the present work from the existing literature. A number of viewpoints are assigned to be visited in a certain sequence to minimize the total travel distance. The problem turns out to be a variant of the well-known Traveling Salesmen Problem (TSP), namely the Single depot multiple Traveling Salesmen Problem (mTSP). Comparisons between the commonly-used prespecified starting depot approach and the proposed formulations are performed and the efficacy of the results is presented through simulations. It is noted that by using the new approach, the total travel distance can be improved by an average of about 20 % compared to the case where the starting depot is prespecified, and by about 40 % in the worst-case scenario (in terms of the starting depot). 相似文献