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Traumatic brain injury and sight loss in military and veteran populations–a review

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military medical Research 2022年第1期9卷 71-85页

作者： Syeda F.hussain Zara Raza Andrew T.G.Cash Thomas Zampieri Robert A.mazzoli Randy h.Kardon Renata S.m.gomes Research&Innovation Blind Veterans UK12-14 Harcourt StreetLondon W1H 4HDUK. Bravo Victor Research12-14 Harcourt StreetLondon W1H 4HDUK Blinded Veterans Association 1101 King StreetSuite 300AlexandriaVirginia 22314USA Department of Ophthalmology Madigan Army Medical Center9040 Jackson AvenueTacomaWashington 98431USA lowa City VA health Care System and Iowa City VA Center for the Prevention and Treatment of Visual Loss Iowa CityIowa 52246USA department of Ophthalmology and Visual Sciences The University of IowaIowa CityIowa 52242USA Northern hub for Veterans and military Families Research Department of NursingMidwifery and HealthFaculty of Health and Life SciencesNorthumbria UniversityNewcastle NE77XAUK.

War and combat exposure pose great risks to the vision *** recently,vision related deficiencies and impairments have become common with the increased use of powerful explosive devices and the subsequent rise in incidence of traumatic brain injury(TBI).Studies have looked at the effects of injury severity,aetiology of injury and the stage at which visual problems become *** was little discrepancy found between the frequencies or types of visual dysfunctions across blast and non-blast related groups,however complete sight loss appeared to occur only in those who had a blast-related ***,the more severe the injury,the greater the likelihood of specific visual disturbances occurring,and a study found total sight loss to only occur in cases with greater *** of mild TBI(mTBI)is *** able to identify a potential TBI via visual symptoms may offer a new avenue for diagnosis.

关键词： Traumatic brain injury Visual impairment military Veteran

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

Ultrafast control of fractional orbital angular momentum of microlaser emissions

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Light(Science & Applications) 2020年第1期9卷 286-294页

作者： Zhifeng Zhang haoqi Zhao Danilo gomes Pires Xingdu Qiao Zihe Gao Josep *** Stefano Longhi Natalia m.Litchinitser Liang Feng Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA 19104USA Department of Electrical and Computer Engineering Duke UniversityDurhamNC 27708USA Department of materials Science and Engineering University of PennsylvaniaPhiladelphiaPA 19104USA Department of Electrical and Computer Engineering Northeastern UniversityBostonMA 02115USA Dipartimento di Fisica Politecnico di Milano and Istituto di Fotonica e Nanotecnologie del Consiglio Nazionale delle RicerchePiazza L.da Vinci 32I-20133 MilanoItaly Instituto de Fisica Interdisciplinar y Sistemas Complejos IFISC(CSIC-UIB) Palma de MallorcaSpain

On-chip integrated laser sources of structured light carrying fractional orbital angular momentum(FOAm)are highly desirable for the forefront development of optical communication and quantum information-processing *** integrated vortex beam generators have been previously demonstrated in different optical settings,ultrafast control and sweep of FOAm light with low-power control,suitable for high-speed optical communication and computing,remains *** we demonstrate fast control of the FOAm from a vortex semiconductor microlaser based on fast transient mixing of integer laser vorticities induced by a control pulse.A continuous FOAm sweep between charge 0 and charge+2 is demonstrated in a 100 ps time window,with the ultimate speed limit being established by the carrier recombination time in the gain *** results provide a new route to generating vortex microlasers carrying FOAm that are switchable at Ghz frequencies by an ultrafast control pulse.

关键词： momentum fractional vortex

Species diversity,population structure and regeneration of woody species in fallows and mature stands of tropical woodlands of southeast Angola

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Journal of Forestry Research 2018年第6期29卷 1569-1579页

作者： Francisco m.P.Goncalves Rasmus Revermann manuel J.Cachissapa Amandio L.gomes marcos P.m.Aidar herbarium of Lubango ISCED HuilaSarmento Rodrigues Str.230 LubangoAngola Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany Department of Biology Faculty of SciencesAgostinho Neto UniversityAv.4 de Fevereiro 714th FloorLuandaAngola Plant Physiology and Biochemistry Institute of BotanyCP 3005Sao PauloSP CEP:01061-970Brazil

This study in the dry tropical woodlands of SE Angola in Cuando-Cubango Province assessed the diversity and composition of woody species in fallows compared to those in mature woodlands. We assessed the population structure of the most harvested woody species by calculating size class distribution and evaluated their regeneration potential based on the density of saplings. The vegetation was surveyed in 20 plots of 20 × 50 m(1000 m2). In each plot, we measured the diameter at breast height(DBh) of all woody species with DBh ≥ 5 cm. The saplings were counted, identified and recorded; 718 individuals, corresponding to 34 species in 32 genera and 15 families were recorded. The size class distribution of target woody species showed three different patterns in fallows and mature woodlands. In general,most of the smaller diameter classes had more individuals than the larger ones did, showing that the regeneration may take place. however, in some diameter classes, the absence of larger stems indicated selective logging of larger trees. Few saplings were recorded in the fallows or mature woodlands; fire frequency and intensity is probably the main obstacle for seed germination and seedling survival rates in the studied area.

关键词： Baikiaea woodlands Fallows mature woodlands Regeneration Woody species

Analytical model for thermal lensing and spherical aberration in diode side-pumped Nd:YAG laser rod having Gaussian pump profile

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Chinese Physics B 2015年第12期24卷 334-341页

作者： m h moghtader Dindarlu m Kavosh Tehrani h Saghafifar A maleki Institute of Optics and Laser Malek-Ashtar University of Technology

In this paper, according to the temperature and strain distribution obtained by considering the Gaussian pump profile and dependence of physical properties on temperature, we derive an analytical model for refractive index variations of the diode side-pumped Nd：YAG laser rod. Then we evaluate this model by numerical solution and our maximum relative errors are 5% and 10% for variations caused by thermo–optical and thermo–mechanical effects; respectively. Finally, we present an analytical model for calculating the focal length of the thermal lens and spherical aberration. This model is evaluated by experimental results.

关键词： side-pumped laser rod Gaussian pump profile thermal effects thermal lens spherical aberration

microstructure evolution of a recycled Al-Fe-Si-Cu alloy processed by tube channel pressing

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International Journal of minerals,metallurgy and materials 2018年第10期25卷 1166-1172页

作者： m.h.Farshidi m.Rifai h.miyamoto Department of materials Science and metallurgical Engineering Ferdowsi University of Mashhad Department of mechanical Engineering Doshisha University

Although excellent recyclability is one of the advantages of Al alloys, a recycling process can reduce different properties of these alloys by adding coarse AlFeSi particles into the alloys' microstructures. One of the well-known methods for modifying the microstructure of metallic materials is the imposition of severe plastic deformation(SPD). Nevertheless, the microstructure evolutions of recycled Al alloys containing extraordinary fractions of AlFeSi particles during SPD processing have seldom been considered. The aim of the present work is to study the microstructure evolution of a recycled Al–Fe–Si–Cu alloy during SPD processing. For this purpose, tubular specimens of the mentioned alloy were subjected to different numbers of passes of a recently developed SPD process called tube channel pressing(TCP); their microstructures were then studied using different techniques. The results show that coarse AlFeSi particles are fragmented into finer particles after processing by TCP. however, decomposition and dissolution of AlFeSi particles through TCP processing are negligible. In addition, TCP processing results in an increase in hardness of the alloy, which is attributed to the refinement of grains, to an increase of the dislocation density, and to the fragmentation of AlFeSi particles.

关键词： AlFeSi intermetallic particle severe plastic deformation microstructure tube channel pressing

Solvability of a class of PT-symmetric non-hermitian hamiltonians：Bethe ansatz method

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Chinese Physics B 2017年第6期26卷 14-21页

作者： m Baradaran h Panahi Department of Physics University of Guilan Rasht 41635-1914Iran

We use the Bethe ansatz method to investigate the Schrdinger equation for a class of PT-symmetric non-hermitian hamiltonians. Elementary exact solutions for the eigenvalues and the corresponding wave functions are obtained in terms of the roots of a set of algebraic equations. Also, it is shown that the problems possess sl（2） hidden symmetry and then the exact solutions of the problems are obtained by employing the representation theory of sl（2） Lie algebra. It is found that the results of the two methods are the same.

关键词： PT-symmetry Bethe ansatz method Lie algebraic approach quasi-exactly solvable

A STABILITY ThEOREm FOR CONSTRAINED OPTImAL CONTROL PROBLEmS

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Journal of Computational mathematics 2004年第5期22卷 633-640页

作者： m.h.Farag DepartmentofmathematicsandComputerScienceFacultyofEducation lbriSultanateofOman

This paper presents the stability of difference approximations of an optimal control problem for a quasilinear parabolic equation with controls in the coefficients, boundary conditions and additional restrictions. The optimal control problem has been convered to one of the optimization problem using a penalty function technique. The difference approximations problem for the considered problem is obtained. The estimations of stability of the solution of difference approximations problem are proved. The stability estimation of the solution of difference approximations problem by the controls is obtained.

关键词： Optimal control Quasilinear Parabolic equations Penalty function methods Finite difference method Stability estimations

multi-task Joint Sparse Representation Classification Based on Fisher Discrimination Dictionary Learning

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Computers, materials & Continua 2018年第10期57卷 25-48页

作者： Rui Wang miaomiao Shen Yanping Li Samuel gomes School of Communication and Information Engineering Shanghai UniversityNo.99 Shangda RoadShanghai200444China School of mechatronics MethodsModels and Skills Laboratory(M3M)Universite de Technologie de Belfort-Montbeliard90010 Belfort cedexBelfortFrance

Recently,sparse representation classification(SRC)and fisher discrimination dictionary learning(FDDL)methods have emerged as important methods for vehicle *** this paper,inspired by recent breakthroughs of discrimination dictionary learning approach and multi-task joint covariate selection,we focus on the problem of vehicle classification in real-world applications by formulating it as a multi-task joint sparse representation model based on fisher discrimination dictionary learning to merge the strength of multiple features among multiple *** improve the classification accuracy in complex scenes,we develop a new method,called multi-task joint sparse representation classification based on fisher discrimination dictionary learning,for vehicle *** our proposed method,the acoustic and seismic sensor data sets are captured to measure the same physical event simultaneously by multiple heterogeneous sensors and the multi-dimensional frequency spectrum features of sensors data are extracted using mel frequency cepstral coefficients(mFCC).moreover,we extend our model to handle sparse environmental *** experimentally demonstrate the benefits of joint information fusion based on fisher discrimination dictionary learning from different sensors in vehicle classification tasks.

关键词： multi-sensor fusion fisher discrimination dictionary learning(FDDL) vehicle classification sensor networks sparse representation classification(SRC)