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排序方式: 共有335条查询结果,搜索用时 15 毫秒
1.
Fatemighomi Hamideh Sadat Golalizadeh Mousa Amani Meisam 《Pattern Analysis & Applications》2022,25(2):467-481
Pattern Analysis and Applications - Efficient high-dimensional analyses of hyperspectral datasets and their utilization within classification algorithms is a popular topic in the field of data... 相似文献
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Khalid Alhusayni Raniyah Wazirali Mousa AlAkhras Marwah Almasri Samah Alhazmi 《计算机系统科学与工程》2023,45(1):459-481
The Internet of Things (IoT) is a network of heterogeneous and smart devices that can make decisions without human intervention. It can connect millions of devices across the universe. Their ability to collect information, perform analysis, and even come to meaningful conclusions without human capital intervention matters. Such circumstances require stringent security measures and, in particular, the extent of authentication. Systems applied in the IoT paradigm point out high-interest levels since enormous damage will occur if a malicious, wrongly authenticated device finds its way into the IoT system. This research provides a clear and updated view of the trends in the IoT authentication area. Among the issues covered include a series of authentication protocols that have remained research gaps in various studies. This study applies a comparative evaluation of authentication protocols, including their strengths and weaknesses. Thus, it forms the foundation in the IoT authentication field of study. In that direction, a multi authentication architecture that involves secured means is proposed for protocol authentication. Informal analysis can affect the security of the protocols. Burrows-Abadi-Needham (BAN) logic provides proof of the attainment of mutual authentication. NS3 simulator tool is used to compare the performance of the proposed protocol to verify the formal security offered by the BAN logic. 相似文献
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In this paper, we develop a joint quality control and preventive maintenance policy for a production system producing conforming
and nonconforming units. The considered system consists of one machine which must supply another production line operating
on a just-in-time basis. Each lot produced by the machine is subject to a quality control. According to the proportion l of nonconforming units observed and compared to a threshold value l
m
, one decides to undertake or not maintenance actions on the system. In order to palliate perturbations caused by the stopping
of the machine for preventive and corrective maintenance actions of random durations, a buffer stock h is built up to ensure the continuous supply of the subsequent production line. The proposed strategy is modelled using simulation
and experimental design. This approach allows to generate a second order response surface allowing to easily determine the
optimal rate, lm*{l_{m}^*}, of nonconforming units on the basis of which preventive maintenance actions should be performed, and the optimal size, h*, of the buffer stock to be built. These values minimize the total cost per time unit which includes the costs related to
maintenance, quality and inventory. 相似文献
6.
Abdelhakim Khatab Nidhal Rezg Daoud Ait-Kadi 《Journal of Intelligent Manufacturing》2011,22(6):885-889
In this paper we consider the block replacement policy (BRP) for a system operating over a random time horizon. Under such
a policy, a system is replaced by a new one either at failure or at a given time interval. The optimality criterion is the
expected total replacements cost. Conditions under which an optimal replacement period exits are given. It is shown that BRP
over an infinite time horizon is obtained as a particular case of the present work. A numerical example is given to illustrate
the proposed replacement model. 相似文献
7.
Relaxation oscillations occur when a capacitor is inserted in series with a field emission tube, a DC high-voltage power supply, and a ballast resistor. The waveform of these oscillations is highly reproducible with a dominant frequency of 200 MHz and a decay time of 20 ns. The peak current as high as 320 mA has been observed although the tungsten emitter is only rated for 10 microA. We have shown that these oscillations are due to a displacement current, charging of the anode-tip capacitance, and are not of a field emission origin. We conclude that the effects of displacement current should be considered in measurements of field emission with microsecond pulses, where high-current densities can be observed. 相似文献
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Mohamed M. El Nady Naira M. Lotfy Doaa A. Mousa 《Petroleum Science and Technology》2016,34(16):1496-1502
The authors aimed to examine a multivariate statistical analysis approach for monitoring the hydrocarbon potentiality of source rocks in the North Western Desert to recognize the potentiality of source rocks and subsequently investigate the maturation level of the proven potential source formations for oil preservation. To achieve this aim, they applied multivariate statistics analysis (principle component analysis [PCA], cluster analysis, and correlation coefficient) and Rock-Eval pyrolysis analyses. The results showed that both PCA and cluster analyses have showed two types of source rocks. The first is classified as poor to fair source rock and immature to marginally mature source rock, the second is considered as fair to good source rock and mature to post mature source rock. PCA extracted two independent factors, which explained 81.87% of the total variance. The first type of source rock was responsible for 50% of the total variance and was best represented by variables TOC, S2, OI, and Ro, and the second one was responsible for 31.65% of the total variance and was represented by the HI variable. Pearson correlation coefficient showed a significant positive correlation between TOC and S2 or Ro. A positive correlation between S2 and HI or OI and also between OI and Ro was observed, while no significant correlation was noticed between HI and Ro. 相似文献
9.
Ghayth Rigane Mohamed Bouaziz Nidhal Baccar Samira Abidi Sami Sayadi Ridha Ben Salem 《Journal of food science》2012,77(10):C1077-C1083
Abstract: A very simple method is proposed to produce hydroxytyrosol, a commercially unavailable compound with well‐known biological properties which justify a potential commercial application. The 2‐phase Chemlali olive pomace is selected as substrate for chemical treatment. Different conditions of chemical treatment, including concentration of acid and alkaline solutions, time and temperature, were assayed. A high amount of hydroxytyrosol (1360 mg/kg of fresh 2‐phase olive pomace) was obtained using water bath after treatment at 80 °C for 90 min with 1 M of H3PO4. However, treatment of 2‐phase Chemlali olive pomace using autoclave apparatus could produce a large amount of hydroxytyrosol (1993.60 and 1515.88 mg/kg of fresh alperujo, 1 M acid and basic catalyst, respectively). By taking into consideration practical and economic aspects, acid‐catalyzed treatment was more effective using autoclave conditions, whereas the alkali catalyzed conditions were not very suitable. This study could provide useful information for industry to produce the potentially bioactive compound. Practical Application: The 2‐phase Chemlali olive pomace is selected as substrate for chemical treatment. Treatment of “alperujo” using water bath or autoclave apparatus was carried out. A high amount of hydroxytyrosol was obtained using autoclave apparatus. 相似文献
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