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91.
The kinetics and mechanism of absorption/desorption of nitrogen in liquid Nb were investigated in the temperature range of 2470 °C to 2670 °C in samples levitated in a N2/Ar stream with various nitrogen partial pressures. The nitrogen solution reaction in liquid Nb was found to be exothermic, with the standard enthalpy and entropy of solution of −236.4 ± 23.3 kJ/mol and −-5.3 ± 8.3 J/K · mol, respectively. Above the threshold flow rate of the N2/Ar stream, the absorption process was determined to be second order with respect to nitrogen concentration, indicating that the rate-controlling step is either the adsorption of nitrogen molecules on the liquid surface or dissociation of adsorbed nitrogen molecules into surface-adsorbed atoms. The desorption process was found to be second order as well. At lower flow rates, however, the absorption rate was found to depend on the gas-phase mass transfer rate. The rate equation for nitrogen absorption in the range of 2470 °C to 2670 °C is given by with the value ofQ calculated to be −327.2 ± 20.6 kJ/mol, while nitrogen desorption at 2670 °C follows the relation   相似文献   
92.
Knowledge and Information Systems - Developing effective and efficient data stream classifiers is challenging for the machine learning community because of the dynamic nature of data streams. As a...  相似文献   
93.
Artificial Intelligence Review - Nowadays we see huge amount of information is available on both, online and offline sources. For single topic we see hundreds of articles are available, containing...  相似文献   
94.
The Journal of Supercomputing - Data availability ensures efficient data accessibility by the readers anytime and from anywhere. It can be addressed by creating multiple copies of each data file...  相似文献   
95.
The Journal of Supercomputing - A correction to this paper has been published: https://doi.org/10.1007/s11227-021-03790-9  相似文献   
96.
Verma  Amit  Dawar  Siddharth  Kumar  Raman  Navathe  Shamkant  Goyal  Vikram 《Applied Intelligence》2021,51(7):4649-4663

High-utility Itemset Mining (HUIM) finds patterns from a transaction database with their utility no less than a user-defined threshold. The utility of an itemset is defined as the sum of the utilities of its items. The utility notion enables a data analyst to associate a profit score with each item and thereof to a pattern. We extend the notion of high-utility with diversity to define a new pattern type called High-utility and Diverse pattern (HUD). The notion of diversity of a pattern captures the extent of the different categories covered by the selected items in the pattern. An application of diverse-pattern lies in the recommendation task where a system can recommend to a customer a set of items from a new class based on her previously bought items. Our notion of diversity is easy to compute and also captures the basic essence of a previously proposed diversity notion. The existing algorithm to compute frequent-diverse patterns is 2-phase, i.e., in the first phase, frequent patterns are computed, out of which diverse patterns are filtered out in the second phase. We, in this paper, give an integrated algorithm that efficiently computes high-utility and diverse patterns in a single phase. Our experimental study shows that our proposed algorithm is very efficient as compared to a 2-phase algorithm that extracts high-utility itemsets in the first phase and filters out the diverse itemsets in the second phase.

  相似文献   
97.
Singh  Dilbag  Kumar  Vijay  Kaur  Manjit 《Applied Intelligence》2021,51(5):3044-3051

The extensively utilized tool to detect novel coronavirus (COVID-19) is a real-time polymerase chain reaction (RT-PCR). However, RT-PCR kits are costly and consume critical time, around 6 to 9 hours to classify the subjects as COVID-19(+) or COVID-19(-). Due to the less sensitivity of RT-PCR, it suffers from high false-negative results. To overcome these issues, many deep learning models have been implemented in the literature for the early-stage classification of suspected subjects. To handle the sensitivity issue associated with RT-PCR, chest CT scans are utilized to classify the suspected subjects as COVID-19 (+), tuberculosis, pneumonia, or healthy subjects. The extensive study on chest CT scans of COVID-19 (+) subjects reveals that there are some bilateral changes and unique patterns. But the manual analysis from chest CT scans is a tedious task. Therefore, an automated COVID-19 screening model is implemented by ensembling the deep transfer learning models such as Densely connected convolutional networks (DCCNs), ResNet152V2, and VGG16. Experimental results reveal that the proposed ensemble model outperforms the competitive models in terms of accuracy, f-measure, area under curve, sensitivity, and specificity.

  相似文献   
98.
Neural Computing and Applications - This work presents an efficient hybridized approach for the classification of electrocardiogram (ECG) samples into crucial arrhythmia classes to detect heartbeat...  相似文献   
99.
Neural Computing and Applications - Induction machines have extensive demand in industries as they are used for large-scale production and, therefore, vulnerable to both electrical and mechanical...  相似文献   
100.
Neural Computing and Applications - In this research article, a novel approach is proposed by considering the sine augmented scaled sine cosine (SAS-SCA) Algorithm for the load frequency control of...  相似文献   
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