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Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey e.Miroshnichenko school of Physics and electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kire.s.y Institute of Physics Department of Mechanical engineering Rowan University school of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very se.s.tive to the.s.ructure ***,we report merging acoustic BICs in a single open resonator,robust against the.s.ructure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are.s.stained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the.s.ructure *** e.s.nce of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,se.s.rs and filte.s.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Free vibration and transient response of double curved beams connected by intermediate.s.raight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI H.GHANDVAR e.JUMAeV s.KHATIR T.CUONG-Le school of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University Unive.s.ty of Busine.s.and science Center for engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate.s.raight beams,which are all constructed from functionally graded porous(FGP) materials. The.s.rain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive.s.iffne.s.and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffne.s. mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire.s.ructure. subsequently, the natural frequencies and transient response of the.s.stem are determined. The accuracy of the mathematical model and the.s.lf-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehe.s.ve.s.udy is conducted to investigate the effects of various paramete.s.on the free vibration and transient response of the considered structure.

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elastic Constants of Nickel Oxide

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Chinese Physics Letters 1991年第3期8卷 153-156页

作者： WANG Jifang FIsHeR,e.s. M.H.Manghnzmi Institute of Physics Academia SinicaBeijing 100080 Argonne National Laboratory ArgonneIllinoisUSA Hawaii Institute of Geophysics University of HawaiiHonoluluHawaiiUSA

Previous me.s.rements of the.s.ngle crystal elastic constants of NiO by ultrasonic techniques have been in wide *** paper gives the results of recent data obtained from several well characterized NiO single *** present results for the antiferromagnetic phase at 298K are different from the previous data and rectify certain questions about the elastic anisotropy ratio C_(44)/C'and bulk modulus K_(s).

关键词： crystals elastic modulus

Improving urban visibility through fractal analysis of street edges： The case of John evans Atta Mills Hish street in Accra, Ghana

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Frontie.s.of Architectural Research 2017年第2期6卷 248-260页

作者： R.A. Oppong A.B. Marful e.s. Asare Department of Architecture College of Art and Built Environment Kwame Nkrumah University of Science and Technology (KNUST) Kumasi Ghana

stree.s.are a representation of cities, and the image of a city is a reflection of its home country. Although attempts to e.s.re harmonious spatial and environmental development in Ghanaian settlements date back to the colonial era, these efforts have minimal physical manifestation in the urban fabric of the city of Accra. The Independence Arch of Ghana, an important landmark in the urban fabric and history of Accra, lacks the.s.riking vista and approach it deserves. This paper introduces the use of fractal analysis of street edges to unde.s.and the characteristics of the John evans Atta Mills （JeAM） High street for developing recommendations to improve visibility along its stretch and the overall image of the city. The box-counting method with visual survey was used in research. The pertinent questions this paper see.s.to addre.s.are as follows： What factors affect the visibility and imageability of JeAM High street？ What design aspects should be considered to improve urban visibility along JeAM High street？ What is the link of fractals to urban design and architecture？ The paper recommends various design considerations and qualities to improve the urban visibility and imageability of JeAM High street.

关键词： Urban Visibitity street edge Fractal Urban design

Validation of LittleeARs questionnaire in Hindi language

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Journal of Otology 2023年第2期18卷 71-78页

作者： Praveen Prakash s.Lakshmi Adithya sreedhar Arena Varan Mathur sreeraj Konadath Department of Audiology All India Institute of Speech and HearingManasagangothriMysuru570006India All India Institute of speech and Hearing ManasagangothriMysuru570006India

Background:subjective me.s.res of auditory development are equally important as objective me.s.res to obtain a realistic image of the hearing status in infants and ***:The objectives of the current study were to translate and validate the LittleeARs questionnaire into the Hindi language,to calculate its psychometric properties and establish a regre.s.on curve of the.s.ores obtained as a function of age,to calculate the inter-test and test retest reliability of the *** secondary objectives were to compare the.s.ores obtained by the normal hearing children and those with hearing impairment and to plot a regre.s.on curve of total scores obtained by the hearing-impaired children as a function of the duration of auditory training attended since their first fit of the *** and methods:The procedures involved conventional translation,reve.s. translation,and content validation before administering the *** translated ve.s.on was administered to parents of 59 children with normal hearing and 41 children with hearing ***:The finalized ve.s.on had good reliability and efficient internal consistency with a Cronbach alpha value of *** mean scores obtained by the normal hearing children showed a progre.s.ve pattern as a function of ***:The LittleeARs questionnaire has been succe.s.ully translated and validated into the Hindi language with excellent validity and reliability and can be used for screening and early identification of hearing impairment and in evaluating the outcome of audiological treatment approaches.

关键词： LittleeARs auditory questionnaire Hindi language Auditory outcome me.s.res screening tools Preverbal auditory checklist

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Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa M.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

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Combinatorial therapies for spinal cord injury repair

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Neural Regeneration Research 2025年第5期20卷 1293-1308页

作者： Carla s.sousa Andreia Monteiro António J.salgado Nuno A.silva Life and Health sciences Research Institute(ICVs) School of MedicineUniversity of MinhoCampus de Gualtar-gualtarBragaPortugal ICVs/3B’s Associate Lab PT Government Associated LabCampus de Gualtar-gualtarBragaPortugal

spinal cord injuries have profound detrimental effects on individuals, regardle.s.of whether they are caused by trauma or non-traumatic events. The compromised regeneration of the.s.inal cord is primarily attributed to damaged neurons, inhibitory molecules, dysfunctional immune response, and glial scarring. Unfortunately, currently, there are no effective treatments available that can fully repair the.s.inal cord and improve functional outcomes. Neverthele.s. numerous pre-clinical approaches have been studied for spinal cord injury recovery, including using biomaterials, cells, drugs, or technological-based strategies. Combinatorial treatments, which target various aspects of spinal cord injury pathophysiology, have been exte.s.vely tested in the last decade. These approaches aim to synergistically enhance repair proce.s.s by addre.s.ng various obstacles faced during spinal cord regeneration. Thus, this review intends to provide.s.ientists and clinicians with an overview of pre-clinical combinatorial approaches that have been developed toward the.s.lution of spinal cord regeneration as well as update the current knowledge about spinal cord injury pathophysiology with an emphasis on the current clinical management.

关键词： electric stimulation neural tissue regeneration neuroprotection polytherapy spinal cord injury

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当代社会科学的特性:两种不同的观点

世界社会科学 1990年第1期 3-8页

作者： e.s.奥弗曼 ,李琥

一、社会科学的科学主义模式和人文主义模式社会科学作为科学的形象是英美人建立的。英美的传统已看到了自然科学、社会科学和人文科学之间的区分,这一传统倾向于认为,社会科学的方法和元理论即使不与自然科学的方法和元理论相同,也是... 详细信息

一、社会科学的科学主义模式和人文主义模式社会科学作为科学的形象是英美人建立的。英美的传统已看到了自然科学、社会科学和人文科学之间的区分,这一传统倾向于认为,社会科学的方法和元理论即使不与自然科学的方法和元理论相同,也是与其相似的;按照这种观点,人文科学在方法上和目的上则完全是另一种样子。在欧洲大陆,这一传统已成为在自然科学和人类科学之间作出基本的划分,后者包括社会科学和人文科学。这种人类科学(或穆勒所称的道德科学和泰勒尔所称的关于人

关键词：社会科学科学主义人文主义人文科学人文学科元理论

Nonlinear state Feedback Control of PeM Fuel Cell systems

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Journal of energy and Power engineering 2010年第2期4卷 8-14页

作者： e.s. Kim C.J. Kim Department of Control and Instrumentation engineering Halla university Wonju 220-712 Republic of Korea Department of Control and lnstrumentation engineering Halla university Wonju 220-712 Republic of Korea

In this paper, the nonlinear state feedback controller has been developed to control the pre.s.res of the oxygen and the hydrogen in the PeM（Proton exchange Membrane） fuel cell system. Nonlinear model of the PeM fuel cell system was introduced to study the design proble.s.of the.s.ate observer and model based controller. A cascade observer using the filtering technique was used to estimate the pre.s.re derivatives of the cathode and the anode in the.s.stem. In order to estimate the pre.s.res of the cathode and the anode, the.s.iding mode observer was designed by using these pre.s.re derivatives. To estimate the oxygen pre.s.re and the hydrogen pre.s.re in the.s.stem, the nonlinear state observer was designed by using the cathode pre.s.re estimates and the anode it. These results will be very useful to design the.s.ate feedback controller. The validity of the proposed observe.s.and the controller has been investigated by using a Lyapunov＇s stability analysis strategy.

关键词： PeM fuel cell cascade observer sliding mode state feedback.