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51.
Nasrollahzadeh Mahmoud Shafiei Nasrin Eslamipanah Mahtab Fakhri Parisa Jaleh Babak Orooji Yasin Varma Rajender S. 《Clean Technologies and Environmental Policy》2020,22(8):1715-1724
Clean Technologies and Environmental Policy - This work reports the fabrication of Au nanoparticles (NPs) by laser ablation of a gold metal plate immersed in water in the absence of stabilizing... 相似文献
52.
Nasri Atefeh Nezafat Zahra Jaleh Babak Orooji Yasin Varma Rajender S. 《Clean Technologies and Environmental Policy》2021,23(6):1797-1806
Clean Technologies and Environmental Policy - Assorted common contaminants namely organic dyes and nitro compounds are generated by various industries and have caused alarming problems for the... 相似文献
53.
Muhammad Islam Kamran Muazzam A. Khan Suliman A. Alsuhibany Yazeed Yasin Ghadi Arshad Jameel Arif Jawad Ahmad 《计算机、材料和连续体(英文)》2022,73(1):657-672
The use of multimedia data sharing has drastically increased in the past few decades due to the revolutionary improvements in communication technologies such as the 4th generation (4G) and 5th generation (5G) etc. Researchers have proposed many image encryption algorithms based on the classical random walk and chaos theory for sharing an image in a secure way. Instead of the classical random walk, this paper proposes the quantum walk to achieve high image security. Classical random walk exhibits randomness due to the stochastic transitions between states, on the other hand, the quantum walk is more random and achieve randomness due to the superposition, and the interference of the wave functions. The proposed image encryption scheme is evaluated using extensive security metrics such as correlation coefficient, entropy, histogram, time complexity, number of pixels change rate and unified average intensity etc. All experimental results validate the proposed scheme, and it is concluded that the proposed scheme is highly secured, lightweight and computationally efficient. In the proposed scheme, the values of the correlation coefficient, entropy, mean square error (MSE), number of pixels change rate (NPCR), unified average change intensity (UACI) and contrast are 0.0069, 7.9970, 40.39, 99.60%, 33.47 and 10.4542 respectively. 相似文献
54.
Yasin Aghazadeh Hashem Kalbkhani Mahrokh G. Shayesteh Vahid Solouk 《Wireless Personal Communications》2018,101(1):305-323
The vision of advanced long-term evolution (LTE-A) project is set to ultimate increase of network capacity in heterogeneous networks (HetNets). In HetNets with small cell configuration, a considerable majority of user devices is eventually connected to the macrocell base station (MBS), while small base stations (BSs), such as femtocell access points (FAPs), are still without any user. This results in unbalanced load and reduces the data rate of macrocell user equipment (MUE). In this paper, a method is proposed for load balancing among FAPs, while desired throughput is achieved. The proposed method uses the estimated received signal strength from different BSs and adjusted pilot signals. Under the critical signal to interference plus noise ratio (SINR) condition, a list of candidate FAPs is prepared. The updated candidate list henceforth does not include the least visited FAPs, which in turn leads to lower unnecessary handoffs. Once the BS with the highest number of free RBs and the highest pilot signal power is selected, FAP allocates the RBs with higher SINRs (qualified RBs) to user. In the case of FAP unavailability, the algorithm compels users to connect to the MBS with adequate qualified RBs. The performance of the proposed method was evaluated under a variety of FAPs density, and the number and velocity of users in terms of throughput and Jain’s fairness index. The results evidence affordable improvements in the throughput and Jain’s index in comparison with other methods. 相似文献
55.
Pinar Gul Verda Turel Nilgun Akgul Mutlu Ozcan 《Journal of Adhesion Science and Technology》2018,32(11):1165-1175
The aim of this study was to measure the translucency of one indirect and direct resin composite after polymerization and to examine the effect of color parameters on this property. Tescera and Filtek Ultimate, each containing three shade groups (Enamel, Dentin and Body for Filtek Ultimate; and Incisal, Opaceous Dentin and Body for Tescera), were investigated. The translucency parameter (TP) was measured as the color difference between a specimen over a white and black background. Significant differences were observed in TP values between shade groups. Tukey’s multiple comparison test revealed TP values among the groups of Filtek Ultimate-Enamel > Tescera-Incisal > Filtek Ultimate-Body > Tescera-Body = Filtek Ultimate-Dentin > Tescera-Opaceous Dentin. In conclusion, it is concluded that the translucency of resin composite was affected by polymerization and color parameters. 相似文献
56.
Muhammed J. Yasin 《Bulletin of Engineering Geology and the Environment》1990,41(1):129-136
The present study is part of the regional engineering geological survey of the western deserts dealing with soil investigations attempting their classification and evaluation for engineering purposes. Field study has revealed that these soils are mainly of residual origin, partly they are colluvial and alluvial. Laboratory test results show that they composed of both coarse and fine fractions. The coarse-grained are mainly of SM-group, less frequently of SC-group. Fine-grained soils are of both CL-and ML groups in equal significance. These soils are seldom free from soluble salts, particularly sulphates in the form of secondary gypsum, some with a high content. Results are discussed in details. Important engineering properties with suitability for engineering use are also given. 相似文献
57.
Mamatov Islombek zelep Yasin Kaar Frat 《Analog Integrated Circuits and Signal Processing》2022,110(1):127-137
Analog Integrated Circuits and Signal Processing - This paper presents carbon nanotube field effect transistor (CNTFET) implementation of voltage differencing current conveyor (VDCC). We propose... 相似文献
58.
Journal of Low Temperature Physics - This study modeled and investigated the magnetocaloric effect in Ni2MnGa Heusler alloy characterized by its magnetic entropy change (ΔSm) and its... 相似文献
59.
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