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Development of A Three-Dimensional Guidance System for Long-Range Maneuvering of A Miniature Autonomous Underwater Vehicle

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China Ocean Engineering 2014年第6期28卷 843-856页

作者： Mansour ATAEI Aghil YOUSEFI-koma Center of Advanced Systems & Technologies Faculty of Mechanical EngineeringCollege of Engineering University of Tehran

The present paper introduces a three-dimensional guidance system developed for a miniature Autonomous Underwater Vehicle（AUV）. The guidance system determines the best trajectory for the vehicle based on target behavior and vehicle capabilities. The dynamic model of this novel AUV is derived based on its special characteristics such as the horizontal posture and the independent diving mechanism. To design the guidance strategy, the main idea is to select the desired depth, presumed proportional to the horizontal distance of the AUV and the target. By connecting the two with a straight line, this strategy helps the AUV move in a trajectory sufficiently close to this line. The adjacency of the trajectory to the line leads to reasonably short travelling distances and avoids unsafe areas. Autopilots are designed using sliding mode controller. Two different engagement geometries are considered to evaluate the strategy＇s performance： stationary target and moving target. The simulation results show that the strategy can provide sufficiently fast and smooth trajectories in both target situations.

关键词： Autonomous Underwater Vehicle(AUV) Three-Dimensional(3D) guidance system Line-of-Sight(LOS) strategy autopilot sliding mode controller

A Novel Efficient Patient Monitoring FER System Using Optimal DL-Features

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Computers, Materials & Continua 2023年第3期74卷 6161-6175页

作者： mousa Alhajlah College of Applied Computer Science King Saud University(Almuzahmiyah Campus)Riyadh11543Saudi Arabia

Automated Facial Expression Recognition(FER)serves as the backbone of patient monitoring systems,security,and surveillance ***-time FER is a challenging task,due to the uncontrolled nature of the environment and poor quality of input *** this paper,a novel FER framework has been proposed for patient *** is performed using contrast-limited adaptive enhancement and the dataset is balanced using *** lightweight efficient Convolution Neural Network(CNN)models MobileNetV2 and Neural search Architecture Network Mobile(NasNetMobile)are trained,and feature vectors are *** Whale Optimization Algorithm(WOA)is utilized to remove irrelevant features from these ***,the optimized features are serially fused to pass them to the classifier.A comprehensive set of experiments were carried out for the evaluation of real-time image datasets FER-2013,MMA,and CK+to report performance based on various *** results show that the proposed model has achieved 82.5%accuracy and performed better in comparison to the state-of-the-art classification techniques in terms of *** would like to highlight that the proposed technique has achieved better accuracy by using 2.8 times lesser number of features.

关键词： Facial expression recognition deep learning transfer learning feature optimization

Underwater Image Enhancement Using Customized CLAHE and Adaptive Color Correction

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Computers, Materials & Continua 2023年第3期74卷 5157-5172页

作者： mousa Alhajlah College of Applied Computer Science King Saud UniversityRiyadhSaudi Arabia

Underwater images degraded due to low contrast and visibility ***,it is important to enhance the images and videos taken in the underwater environment before *** is a way to improve or increase image quality and to improve the contrast of degraded *** original image or video which is captured through image processing devices needs to improve as there are various issues such as less light available,low resolution,and blurriness in underwater images caused by the normal *** researchers have proposed different solutions to overcome these *** channel prior(DCP)is one of the most used techniques which produced a better Peak Signal to Noise Ratio(PSNR)***,DCP has some issues such as it tends to darken images,reduce contrast,and produce halo *** proposed method solves these issues with the help of contrast-limited adaptive histogram equalization(CLAHE)and the Adaptive Color Correction *** proposed method was assessed using Japan Agency for Marine-Earth Science and Technology(JAMSTEC),and some images were collected from the *** measure of entropy(MOE),Measure of Enhancement(EME),Mean Square Error(MSE),and PSNR opted as performance measures during *** values of MSE and PSNR achieved by the proposed framework are 0.26 and 32 respectively which shows better results.

关键词： Enhancement color diminishing contrast fusion technique color balancing technique CLAHE dark channel prior

SYNTHESIS AND CHARACTERIZATION OF ORGANOSOLUBLE POLYAMIDES FROM QUINOXALINE BASED DIAMINE

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Chinese Journal of Polymer Science 2010年第2期28卷 147-155页

作者： Hossein Mighani mousa Ghaemy Department of Chemistry University of Golestan Department of Chemistry University of Mazandaran

Aromatic/aliphatic polyamides were synthesized from a diamine monomer, 2,3-bis-p-aminophenylquinoxaline （IV）, based on quinoxaline and various dicarboxylic acids of aliphatic, aromatic and heterocyclic. The diamine and polyamides were characterized by elemental analysis, FTIR and IH-NMR. The solubility of the polyamides was affected by the quinoxaline and heterocyclic groups in the polymer chain. They were all soluble in common organic solvents such as dimethylsulfoxide （DMSO）, N,N-dimethylformamide （DMF） and N-methylpyrolidone （NMP）. The polyamides showed inherent viscosity in the range of 0.25-0.3 dL/g in DMSO at 25℃ and good thermal stability with the char yields in the range of 65%-82% at 600℃ in nitrogen.

关键词： Quinoxaline Polyamides Solubility Thermal stability

SYNTHESIS AND CHARACTERIZATION OF POLYAMIDES DERIVED FROM(4-(4-(2,6-DIPHENYLPYRIDIN-4YL)PHENOXY)PHENYL)-3,5-DIAMINOBEZAMIDE

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Chinese Journal of Polymer Science 2012年第1期30卷 82-92页

作者： mousa Ghaemy Soheila Khajeh Faculty of Chemistry University of Mazandaran BabolsarIran

New types of polyamides containing pendent triaryl pyridine groups were successfully synthesized by direct polycondensation of a symmetry diamine,（4-（4-（2,6-diphenylpyridin-4yl）phenoxy）phenyl）-3,5-diaminobezamide（DPDAB）, and various aromatic and aliphatic dicarboxylic diacids in NMP using triphenyl phosphate（TPP） and pyridine as catalyst. The diamine and all the prepared polyamides were fully characterized by using FT-IR,~1H-NMR,UV-Vis spectroscopy, fluorimetry and elemental *** inherent viscosity of polyamides ranged from 0.45 dL/g to 0.68 dL/*** the polymers exhibited solubility in common polar aprotic solvents such as NMP,DMAc,DMF,DMSO,pyridine,HMPA,and even in less polar solvents such as THF and m-cresol at room *** properties of polyamides were evaluated by means of DSC,DMTA and *** polymers showed glass transition temperatures（T_g） in the range of 138-210℃. Their initial decomposition temperature（T_i） varied from 265℃to 310℃under N_*** dilute solution（0.2 g/dL） of polyamides in DMF exhibited fluorescence emission withλ_（max） in the range of 470-550 nm.

关键词： Polyamides Synthesis Direct polycondensation Solubility Thermal stability

ORGANOSOLUBLE AND THERMALLY STABLE POLYIMIDES DERIVED FROM A NEW DIAMINE CONTAINING BULKY-FLEXIBLE TRIARYL PYRIDINE PENDENT GROUP

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Chinese Journal of Polymer Science 2011年第4期29卷 465-474页

作者： mousa Ghaemy Soheila Khajeh Faculty of Chemistry University of MazandaranBabolsarIran

A novel kind of aromatic diamine, N-（4-（4-（2,6-diphenyl pyridine-4-yl） phenoxy） phenyl）-3,5-diaminobezamide （DPDAB）, was synthesized via aromatic nucleophilic substitution of 3,5-dinitrobenzoylchloride with 4-（4-（2,6- diphenylpyridine-4-yl）phenoxy）aniline （DPPA）, followed by palladium-catalyzed hydrazine reduction. This monomer was used to prepare polyimides （PIs） based on reaction with several commerically avaiable tetracarboxylic dianhydrides such as pyromellatic dianhydride （PMDA）, benzophenone tetracarboxylic acide dianhydride （BTDA） and bicycle [2.2.2] oct-7-ene- 2, 3,5,6-tetracarboxylic dianhydride （BCDA）. These PIs had inherent viscosity in the range of 0.34-0.76 dL/g and showed good solubility in various aprotic polar solvents. The glass-transition tempratures （Tgs） of the PIs were in the range of 184-302℃, and showed high thermal stability with 10% weight loss in the temperature range of 360-500℃ under nitrogen atmosphere.

关键词： Polyimides Inherent viscosity Solubility Thermal stability DSC.

Partially Deep-Learning Encryption Technique

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Computers, Materials & Continua 2023年第2期74卷 4277-4291页

作者： Hamdy M.mousa Faculty of Computers and Information Menoufia UniversityMenoufia32511Egypt

The biggest problem facing the world is information security in the digital *** protection and integrity are hot topics at all times,so many techniques have been introduced to transmit and store data *** increase in computing power is increasing the number of security breaches and attacks at a higher rate than before on ***,a number of existing security systems are at risk of *** paper proposes an encryption technique called Partial Deep-Learning Encryption Technique(PD-LET)to achieve data ***-LET includes several stages for encoding and decoding digital *** preprocessing,convolution layer of standard deep learning algorithm,zigzag transformation,image partitioning,and encryption key are the main stages of ***,the proposed technique converts digital data into the corresponding matrix and then applies encryption stages to *** implementation of encrypting stages is frequently *** collaboration between deep learning and zigzag transformation techniques provides the best output result and transfers the original data into a completely undefined image which makes the proposed technique efficient and secure via data ***,its implementation phases are continuously changed during the encryption phase,which makes the data encryption technique more immune to some future attacks because breaking this technique needs to know all the information about the encryption *** security analysis of the obtained results shows that it is computationally impractical to break the proposed technique due to the large size and diversity of keys and PD-LET has achieved a reliable security system.

关键词： Encryption technique deep learning security zigzag transformation image partitioning

A NEW APPROACH TO FREE VIBRATION ANALYSIS OF A BEAM WITH A BREATHING CRACK BASED ON MECHANICAL ENERGY BALANCE METHOD

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Acta Mechanica Solida Sinica 2011年第2期24卷 185-194页

作者： mousa Rezaee Reza Hassannejad Department of Mechanical Engineering University of Tabriz

In this paper, a new approach to free vibration analysis of a cracked cantilever beam is proposed. By considering the effect of opening and closing the crack during the beam vibration, it is modeled as a fatigue crack. Also, local stiffness changes at the crack location are considered to be a nonlinear amplitude-dependent function and it is assumed that during one half a cycle, the frequencies and mode shapes of the beam vary continuously with time. In addition, by using the experimental tests, it is shown that the local stiffness at the crack location varies continuously between the two extrerae values corresponding to the fully closed and the fully open cases of the crack. Then, by using the mechanical energy balance the dynamic response of the cracked beam is obtained at every time instant. The results show that for a specific crack depth, by approaching the crack location to the fixed end of the beam, more reduction in the fundamental frequency occurs. Furthermore, for a specific crack location, the fundamental frequency diminishes and the nonlinearity of the system increases by increasing the crack depth. In order to validate the results, the variations of the fundamental frequency ratio against the crack location axe compared with experimental results.

关键词： free vibration fatigue crack beam amplitude-dependent local stiffness superhar-monic time-dependent mode

FREE VIBRATION ANALYSIS OF SIMPLY SUPPORTED BEAM WITH BREATHING CRACK USING PERTURBATION METHOD

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Acta Mechanica Solida Sinica 2010年第5期23卷 459-470页

作者： mousa Rezaee Reza Hassannejad Department of Mechanical Engineering University of Tabriz

In this paper, a new analytical method for vibration analysis of a cracked simply supported beam is investigated. By considering a nonlinear model for the fatigue crack, the governing equation of motion of the cracked beam is solved using perturbation method. The solution of the governing equation reveals the superhaxmonics of the fundamental frequency due to the nonlinear effects in the dynamic response of the cracked beam. Furthermore, considering such a solution, an explicit expression is also derived for the system damping changes due to the changes in the crack parameters, geometric dimensions and mechanical properties of the cracked beam. The results show that an increase in the crack severity and approaching the crack location to the middle of the beam increase the system damping. In order to validate the results, changes in the fundamental frequency ratios against the fatigue crack severities are compared with those of experimental results available in the literature. Also, a comparison is made between the free response of the cracked beam with a given crack depth and location obtained by the proposed analytical solution and that of the numerical method. The results of the proposed method agree with the experimental and numerical results.

关键词： free vibration cracked beam breathing crack damping factor perturbation method