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1.
In the network security system, intrusion detection plays a significant role. The network security system detects the malicious actions in the network and also conforms the availability, integrity and confidentiality of data information resources. Intrusion identification system can easily detect the false positive alerts. If large number of false positive alerts are created then it makes intrusion detection system as difficult to differentiate the false positive alerts from genuine attacks. Many research works have been done. The issues in the existing algorithms are more memory space and need more time to execute the transactions of records. This paper proposes a novel framework of network security Intrusion Detection System (IDS) using Modified Frequent Pattern (MFP-Tree) via K-means algorithm. The accuracy rate of Modified Frequent Pattern Tree (MFPT)-K means method in finding the various attacks are Normal 94.89%, for DoS based attack 98.34%, for User to Root (U2R) attacks got 96.73%, Remote to Local (R2L) got 95.89% and Probe attack got 92.67% and is optimal when it is compared with other existing algorithms of K-Means and APRIORI.  相似文献   
2.
There has been growing research interest in the use of molybdenum disulfide in the fields of optoelectronics and energy harvesting devices, by virtue of its indirect-to-direct band gap tunability. However, obtaining large area thin films of MoS2 for future device applications still remains a challenge. In the present study, the amounts of the precursors (S and MOO3) were varied systematically in order to optimize the growth of highly crystalline and large area MoS2 layers by the chemical vapor deposition method. Careful control of the amounts of precursors was found to the key factor in the synthesis of large area highly crystalline flakes. The thickness of the layers was confirmed by Raman spectroscopy and atomic force microscopy. The optical properties and chemical composition were studied by photoluminescence (PL) and X-ray photoelectron spectroscopy. The emergence of strong direct excitonic emissions at 1.82 eV (A-exciton, with a normalized PL intensity of -55 × 10^3) and 1.98 eV (B-exciton, with a normalized PL intensity of -5 × 10^3) of the sample at room temperature clearly indicates the high luminescence quantum efficiency. The mobility of the films was found to be 0.09 cm^2/(V.s) at room temperature. This study provides a method for the controlled synthesis of high-quality two-dimensional (2D) transition metal dichalcogenide materials, useful for applications in nanodevices, optoelectronics and solar energv conversion.  相似文献   
3.
ZnSe QDs have been synthesized by wet chemical, template free process by zinc acetate and elemental selenium powder in presence of ethylene glycol, hydrazine hydrate and a defined amount of water at 90 °C. The product was in strong quantum confinement regime, having yield as high as 50 %. The transmission electron microscopy image indicated that the particles were well dispersed and spherical in shape. The X-ray diffraction analysis showed that the ZnSe nanoparticles were of the Cubic structure, with average particle diameter of about 3.50 nm. The FTIR characteristic indicates that the N2H4 molecule has intercalated into the complex and formed a molecular precursor.  相似文献   
4.
Vijaya Kumar  P.  Jebakani  D.  Velmurugan  C.  Senthilkumar  V. 《SILICON》2022,14(3):1247-1252
Silicon - In this study, an attempt was made to enhance the mechanical and microstructural properties of aluminium (Al) based FGM with the influence of silicon carbide (SiC) elements. The five...  相似文献   
5.
6.
Wireless Personal Communications - This paper considers half-duplex cooperative spectrum sharing scheme where both primary and secondary systems mutually cooperate with each other to exploit...  相似文献   
7.
International Journal of Mechanics and Materials in Design - The resonant frequency of electromechanical energy harvester should be tuned to ambient frequency so as to maximize the harvester power....  相似文献   
8.
This article presents the characteristics of Carica papaya fibers (CPFs) extracted from the bark of the perennial papaya plant. Detailed chemical compositions of CPFs such as cellulose, lignin, ash, moisture, and wax contents were established and determined by using standard methods. Further, chemical groups, crystalline structure, surface roughness, and thermal stability of CPFs were examined using Fourier transform infrared analysis, X-ray diffraction, atomic force microscope, and thermogravimetric analysis, respectively. The physico-chemical properties of CPFs, crystallinity index (56.34%), cellulose content (38.71 wt. %), hemicellulose (11.8%), and density (943 kg/m3) were compared to those properties of other natural fibers. The results suggest that the biodegradable CPFs can be used as a potential reinforcemnet in the polymer matrix composite structure.  相似文献   
9.
Amides are synthesized directly from alcohols and amines in high yields using an in situ generated catalyst from easily available ruthenium complexes such as the (p‐cymene)ruthenium dichloride dimer, [Ru(p‐cymeme)Cl2]2, or the (benzene)ruthenium dichloride dimer, [Ru(benzene)Cl2]2, an N‐heterocyclic carbene (NHC) ligand, and a nitrogen containing L‐type ligand such as acetonitrile. The phosphine‐free catalyst systems showed improved or comparable activity compared to previous phosphine‐based catalytic systems. The in situ generated catalyst from [Ru(benzene)Cl2]2, an NHC ligand, and acetonitrile showed excellent activity toward reactions with cyclic secondary amines such as piperidine and morpholine.  相似文献   
10.
The application of zeolite Y-multiwalled carbon nanotube (MWCNT) nanocomposite modified glassy carbon electrode (zeolite Y-MWCNT/GCE) in the electroanalysis of Cu2+ ion is presented. In order to bring out the unique advantage of the zeolite Y-MWCNT/GCE, experiments were carried out also at graphite/GCE, MWCNT/GCE and zeolite Y-graphite/GCE. For the same surface area, the performance of zeolite Y-MWCNT/GCE was superior to the other modified electrodes in terms of current sensitivity for Cu2+ ion. The combination of zeolite Y and MWCNT as a nanocomposite resulted in a good synergetic effect. The Cu+2 ion sensor exhibited a linear calibration range between 5 × 10−8 and 1 × 10−5 mol L−1 with a detection limit of 1.12 × 10−8 mol L−1 (0.72 ppb).  相似文献   
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