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Real and Altered Fingerprint Classification Based on Various Features and Classifiers

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Computers, Materials & Continua 2023年第1期74卷 327-340页

作者： Saif Saad Hameed Ismail Taha ahmed Omar Munthir Al Okashi College of Computer Sciences and Information Technology University of AnbarAnbarIraq

Biometric recognition refers to the identification of individuals through their unique behavioral features(e.g.,fingerprint,face,and iris).We need distinguishing characteristics to identify people,such as fingerprints,which are world-renowned as the most reliablemethod to identify *** recognition of fingerprints has become a standard procedure in forensics,and different techniques are available for this *** current techniques lack interest in image enhancement and rely on high-dimensional features to generate classification ***,we proposed an effective fingerprint classification method for classifying the fingerprint image as authentic or altered since criminals and hackers routinely change their fingerprints to generate fake *** order to improve fingerprint classification accuracy,our proposed method used the most effective texture features and *** Analysis(DCA)and Gaussian Discriminant Analysis(GDA)are employed as classifiers,along with Histogram of Oriented Gradient(HOG)and Segmentation-based Feature Texture Analysis(SFTA)feature vectors as *** performance of the classifiers is determined by assessing a range of feature sets,and the most accurate results are *** proposed method is tested using a Sokoto Coventry Fingerprint Dataset(SOCOFing).The SOCOFing project includes 6,000 fingerprint images collected from 600 African people whose fingerprints were taken ten *** distinct degrees of obliteration,central rotation,and z.cut have been performed to obtain synthetically altered replicas of the genuine *** proposal achieved massive success with a classification accuracy reaching 99%.The experimental results indicate that the proposed method for fingerprint classification is feasible and *** experiments also showed that the proposed SFTA-based GDA method outperformed state-of-art approaches in feature dimension and classification accuracy.

关键词： Fingerprint classification HOG SFTA discriminant analysis(DCA)classifier gaussian discriminant analysis(GDA)classifier SOCOFing

Current-fed Quasi z.source Inverter-topology and Control

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Current-fed Quasi Z-source Inverter-topology and Control

作者： Muneeb ahmed 山东科技大学

学位级别：硕士

电流型准阻抗源逆变器是对阻抗源逆变器的一个发展,它与传统阻抗源逆变器的不同之处包括元件额定值较低、电源应力减小、控制容易。传统电流源逆变器有两个主要的问题:单向功率流和只能升压而不能降压,这使得它在许多场合的应用受到限制... 详细信息

电流型准阻抗源逆变器是对阻抗源逆变器的一个发展,它与传统阻抗源逆变器的不同之处包括元件额定值较低、电源应力减小、控制容易。传统电流源逆变器有两个主要的问题:单向功率流和只能升压而不能降压,这使得它在许多场合的应用受到限制,如混合电动汽车、通用变频调速系统等。因其独特的电路结构,电流型准阻抗源逆变器可以通过在传统零状态期间插入独特的开路零状态实现降压功能,这大大提高了逆变器的可靠性,提供了诱人的单级逆变功率变换可实现升降压的功能。在输入电压大范围变化的场合,这种逆变器是一种非常有竞争力的电路拓扑。本论文从电流型准阻抗源逆变器的拓扑结构、工作原理开始讨论,主要研究了其调制方法,包括空间矢量控制方法及其FPGA数字实现,同时也涉及到了该逆变器的设计方法。提出了三种具有不同升压比的PWM控制方法,为了减小开关损耗,提出了一种改进的SVPWM控制方法,并对该方法与通用的方法进行了对比。论文对电流型准阻抗源逆变器的新特点,包括优越的升降压功能、较高的可靠性、较小的无源元件定额以及独特的可再生反馈能力等进行了综合研究。论文最后给出了一些仿真结果,以验证理论分析的正确性。

关键词：电流源逆变器脉冲宽度调制电流型准阻抗源逆变器空间矢量脉冲宽度调制

An Investigation of Scaled-FLC Using PSO for Multi-area Power System Load Frequency Control

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Energy and Power Engineering 2013年第4期5卷 458-462页

作者： Aqeel S. Jaber A.z. Ahmad ahmed N Abdalla Faculty of Electrical and Electronics Engineering University Malaysia Pahang Pekan Malaysia Faculty of Electrical and Electronics Engineering University Malaysia Pahang Pekan Malaysia Sustainable En.& Power Elec. Res. (SuPER) Group University Malaysia Pahang Pekan Malaysia

Load Frequency Control (LFC) is one of power systems important requirements which maintain the z.ro steady-state errors in the frequency changing and restoring the natural frequency to its normal position. Many problems are subject to LFC such as suddenly large load or suddenly disconnecting generating unit by the protection device. In this paper, multi-area Frequency Control by using the combination of PSO and fuz.y logic control (FLC) technique. PSO optimiz.tion method is used to tuning the fuz.y controller input and output gains. Four of an interconnected electrical power system used as a testing the effectiveness of the proposed method compared to a conventional PI controller and scaled-fuz.y controller. The simulation result has been shown that the controller can generate the best dynamic response in multi-load conditions.

关键词： Fuz.y Control PSO Load Frequency Control

A new heterojunction in photocatalysis:S-scheme heterojunction

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Chinese Journal of Catalysis 2021年第5期42卷 667-669页

作者： S.Wageh ahmed A.Al-Ghamdi Rashida Jafer Xin Li Peng z.ang 沙特阿拉伯阿卜杜勒-阿齐兹国王大学理学院物理系沙特阿拉伯华南农业大学林学与风景园林学院农业部能源植物资源与利用重点实验室广东广州510642 郑州大学材料与工程学院低碳环保材料智能设计国际联合研究中心河南郑州450001

To harness abundant and clean solar energy along with relieving energy and environmental issues,photocatalysis holds great ***-based photocatalysts are crucial to its successful ***,the photocatalytic efficiency based on a unitary semiconductor material falls short of expectations,mainly because of the rapid recombination of photogenerated electrons and *** originates in the extremely strong Columbic force between ***,it is impossible for a single photocatalyst to achieve wide light absorption and ample redox ability concurrently.

关键词： S型异质结异质结光催化剂电荷分离机制充电转移路线 z.光催化剂

A numerical study of anti-vortex film-cooling holes designs in a 1-1/2 turbine stage using LES

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Propulsion and Power Research 2019年第4期8卷 275-299页

作者： Nabeel Al-z.rfi Ali Turan Adel Nasser ahmed Alhusseny Department of Mechanical Engineering Faculty of EngineeringUniversity of KufaNajafIraq Visiting Researcher Department of MechanicalAerospace and Civil EngineeringSchool of EngineeringFaculty of Science and EngineeringThe University of ManchesterManchesterM139PLUK Department of Mechanical Aerospace and Civil EngineeringSchool of EngineeringFaculty of Science and EngineeringThe University of ManchesterManchesterM139PLUK

The primary focus of the present study is to investigate the impact of anti-vortex holes design on the film-cooling performance in a film-cooled rotor blade model using the large eddy simulation method(LES).One row of the film holes was positioned on the pressure surface of the rotor *** row had three cylindrical holes(the main hole in the present study)with a diameter(D)of 4 mm and a tangential injection angle of 28 *** main hole supplemented with the addition of two symmetrical side holes(anti-vortex holes),which branch out from the same main *** positions for the anti-vortex side holes were considered;namely:upstream to the outlet of the main hole;in line with the main hole;and downstream of the main *** Reynolds number was fixed at Re z.1.92105 and the speed of the rotor blade was taken to be 1800 *** blowing ratio varied from 1.0 to 5.0 and the density ratio of coolant to mainstream was *** to the base hole,the film cooling performance of the all anti-vortex cases showed obvious improvement at all blowing *** middle stream side holes and downstream side holes each demonstrated good film cooling performance at all blowing ratios,while the upstream side holes perform well only at a lower blowing *** presence of side holes can restrain the CRVP(counter rotating vortex pairs)intensity of the main hole and reduce the coolant lift-off,improving the film coverage and film cooling *** downstream side holes can perform better in reducing the CRVP intensity.

关键词： Rotor blade Large eddy simulation Film-cooling effectiveness Turbulence Rotation Anti-vortex hole

Syntheses, Characteriz.tion and Crystal Structures of Two Novel Oxaz.line Based Titanium Complexes

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Chinese Journal of Structural Chemistry 2015年第7期34卷 1121-1134页

作者： MUHAMMAD Hafeez.MUHAMMAD Naeem ahmed SONJA Lippert WINFRIED P.Krtetschmer Department of Chemistry The University of Azad Jammu and Kashmir Inorganic Chemistry II University of Bayreuth

Two novel titanium compounds [（E）-N＇-（2,6-diisopropylphenyl）-N-（2-（4,4-dimethyl-4,5-dihydrooxaz.l-2-yl）phenyl）benz.midamido]titanium trichloride（1） and [N-（2-（4,4-dimethyl-4,5-dihydrooxaz.ol-2-yl）phenyl）-6-（2,4,6-triisopropyl-phenyl） pyridin-2-amido]titanium trichloride（2） were synthesiz.d by reacting the corresponding ligand with diethylaminetitaniumtrichloride in equal molar ratios. The compounds were characteriz.d with 1H, 13 C NMR, elemental analysis and single-crystal X-ray diffraction analysis. The geometry of both compounds is distorted octahedron. The three nitrogen and one chlorine atoms are in the equatorial plane. Compound 1 crystalliz.s in orthorhombic system, space group P212121 with a = 10.3520（4）, b = 16.5750（7）, c = 17.1530（7） , z.= 4 and V = 2943.2（2）3. Compound 2 crystaliz.s in the monoclinic system, space group P21/n with a = 15.6400（11）, b = 10.12.60（7）, c = 22.9120（14）, z.= 4 and V = 3558.5（4）3. The synthesiz.d compounds were employed for ethylene polymeriz.tion catalysis. Both complexes showed moderate activity when activated with dry methylaluminoxane（d MAO） and complex 1 produced very high molecular weight polyethylene.

关键词： octahedron polymeriz.tion titanium trichloride X-ray

Performance analysis of a random ARQ initializ.d cooperative communication protocol in shadowed Nakagami-m wireless channel

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Science in China(Series F) 2009年第6期52卷 1027-1036页

作者： ahmed Irfan PENG MuGen WANG WenBo SHAH Syed Ismail Wireless Signal Processing and Network Laboratory Beijing University of Posts and Telecommunications Real-Time MIMO Test-Bed Laboratory Iqra University Islamabad Pakistan

In this paper, we develop and analyz. an energy efficient ARQ （automatic repeat request） initializ.d transmit diversity protocol for cooperative *** access control （MAC） layer packet retransmission limit （similar to aShortRetryLimit or aLongRetryLimit [802.11-1997]） has been used as an actuator for transmit cooperative diversity *** take the channel state information （CSI） as a function of retransmission tries and the number of retransmission tries is modeled as a random *** close to the source node are chosen for the transmit *** form expressions are obtained for symbol error rate （SER）, outage capacity and outage probability for the proposed scheme in shadowed fading *** cooperative scheme achieves lower signal-to-noise ratio （SNR）, stumpy outage probability, higher bandwidth, and transmit energy efficiencies for desired average symbol error rate （ASER） than the preceding ARQ based cooperative ***, the results of computer simulations are included to demonstrate the efficacy of the proposed scheme and to verify the accuracy of the analytical expressions.

关键词： automatic repeat request (ARQ) cooperative transmit diversity composite shadowed fading channel wireless networks

Muon-pair Production in the Left-right Symmetric Model at z.0-factory

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Muon-pair Production in the Left-right Symmetric Model at Z ...

作者： Mahfoudh ahmed Beiba 中国科学技术大学

学位级别：硕士

The potential for probing the impacts of the left-right symmetric model（LRM） onthe process e

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Protective Coatings Containing z.MOF-BTA Metal–Organic Framework for Active Protection of AA2024-T3

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1893-1908页

作者： Iz.chukwu K.Nwokolo Hongwei Shi Paul CUz.ma Sharjeel ahmed Jiwen Li Fuchun Liu CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China z.U-UIUC Institute International CampusZhejiang UniversityHaining314400China Institute of Corrosion Science and Technology Guangzhou510530China

z.MOF-BTA,a new metal–organic framework with excellent anti-corrosion properties was prepared and *** and immersion tests in 3.5 wt%NaCl were performed on AA2024-T3 alloy to assess the corrosion inhibition ability of *** showed an inhibition efficiency of more than 90%,indicating excellent corrosion inhibition of z.MOF-BTA on AA 2024-T3 in ***,z.MOF-BTA particles were incorporated into polyurethane coatings to create corrosion-resistant *** tests and neutral salt spray analysis were used to assess the corrosion protection ability of z.MOF-BTA-laden polyurethane *** results of electrochemical impedance spectra clearly showed the outstanding corrosion resistance and durability of z.MOF-BTA coatings after 1440 h of immersion with a high pore resistance(Rpo)of 1.76×10^(10)Ωcm^(2).In addition,during the cross-cut adhesion test,the coating did not detach from the substrate,and after the impact test,there was scarcely any indication of a fracture,which further supports the notion that the coating has strong adhesion to the substrate.

关键词： Aluminum alloy Benz.triaz.le Corrosion inhibition Electrochemical impedance spectroscopy(EIS) Metal-organic framework Organic coatings