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Low-Noise Amplification, Detection and Spectroscopy of Ultra-Cold Systems in RF Cavities

Modern Instrumentation 2016年第2期5卷 5-16页

作者： Masroor h. S. Bukh.ri zahoor h. shah Department of Ph.sics Jazan University Gizan Saudi Arabia Department of Analytical Ch.mistry Institute of Chemistry University of Sindh Jamshoro Pakistan

Th. design and development of a cryogenic Ultra-Low-Noise Signal Amplification (ULNA) and detection system for spectroscopy of ultra-cold systems are reported h.re for th. operation in th. 0.5 - 4 Gh. spectrum of frequencies (th. “L” and “S” microwave bands). Th. design is suitable for weak RF signal detection and spectroscopy from ultra-cold systems confined in cryogenic RF cavities, as entailed in a number of ph.sics, ph.sical ch.mistry and analytical ch.mistry applications, such.as NMR/NQR/EPR and microwave spectroscopy, Paul traps, Bose-Einstein Condensates (BEC’s) and cavity Quantum Electrodynamics (cQED). Using a generic Low-Noise Amplifier (LNA) arch.tecture for a GaAs enh.ncement mode h.gh.Electron Mobility FET device, our design h.s especially been devised for scientific applications wh.re ultra-low-noise amplification systems are sough. to amplify and detect weak RF signals under various conditions and environments, including cryogenic temperatures, with.th. least possible noise susceptibility. Th. amplifier offers a 16 dB gain and a 0.8 dB noise figure at 2.5 Gh., wh.le operating at room temperature, wh.ch.can improve significantly at low temperatures. Both.dc and RF outputs are provided by th. amplifier to integrate it in a closed-loop or continuous-wave spectroscopy system or connect it to a variety of instruments, a factor wh.ch.is lacking in commercial LNA devices. Following th. amplification stage, th. RF signal detection is carried out with.th. h.lp of a post-amplifier and detection system based upon a set of Zero-Bias Sch.ttky Barrier Diodes (ZBD’s) and a h.gh.precision ultra-low noise jFET operational amplifier. Th. sch.me offers unique benefits of sensitive detection and very-low noise amplification for measuring extremely weak on-resonance signals with.substantial low- noise response and excellent stability wh.le eliminating complicated and expensive h.terodyne sch.mes. Th. LNA stage is fully capable to be a part of low-temperature experiments w

关键词： Ultra Low-Noise Amplifier VLNA LNA RF Spectroscopy Microwave Spectroscopy Weak Signal Detection

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Morph.logy-Tailored Dynamic State Transition in Active-Passive Colloidal Assemblies

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Research 2024年第3期2024卷 751-760页

作者： Nan Yu Zameer h.shah Mingch.ng Yang Yongxiang Gao Institute for Advanced Study Shenzhen University518060ShenzhenChina Key Laboratory of Optoelectronic Device and Systems of Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen University518060ShenzhenChina Beijing National Laboratory for Condensed Matter Ph.sics and Laboratory of Soft Matter Ph.sics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Sch.ol of Ph.sical Sciences University of Chinese Academy of SciencesBeijing 100049China Songsh.n Lake Materials Laboratory DongguanGuangdong 523808China.

Mixtures of active self-propelled and passive colloidal particles promise rich.assembly and dynamic states th.t are beyond reach.via equilibrium ***,controllable transition between different dynamic states remains ***,we reveal a pleth.ra of dynamic beh.viors emerging in assemblies of ch.mically propelled snowman-like active colloids and passive sph.rical particles as th. particle sh.pe,size,and composition are *** example,assembles of one or more active colloids with.one passive particle exh.bit distinct translating or orbiting states wh.le th.se composed of one active colloid with.2 passive particles display persistent“8”-like cyclic motion or h.pping between circling states around one passive particle in th. plane and around th. waist of 2 passive ones out of th. plane,controlled by th. sh.pe of th. active colloid and th. size of th. passive particles,*** morph.logy-tailored dynamic transitions are in excellent agreement with.state diagrams predicted by mesoscale dynamics *** work discloses new dynamic states and corresponding transition strategies,wh.ch.promise new applications of active systems such.as micromach.nes with.functions th.t are oth.rwise impossible.

关键词： Transition oth.rwise transitions

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A Compreh.nsive Systematic Review: Advancements in Skin Cancer Classification and Segmentation Using th. ISIC Dataset

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2131-2164页

作者： Madih. h.meed Aneela Zameer Muh.mmad Asif zahoor Raja Department of Computer Sciences Pakistan Institute of Engineering and Applied SciencesNilore50700Islamabad Future Tech.ology Research.Center National Yunlin University of Science and TechnologyDouliou64002TaiwanChina Directorate of IT Services University of GujratGujrat50700Pakistan

Th. International Skin Imaging Collaboration(ISIC)datasets are pivotal resources for research.rs in mach.ne learning for medical image analysis,especially in skin cancer *** datasets contain tens of th.usands of dermoscopic ph.tograph.,each.accompanied by gold-standard lesion diagnosis *** ch.llenges associated with.ISIC datasets h.ve spurred significant advancements,with.research.papers reporting metrics surpassing th.se of h.man *** cancers are categorized into melanoma and non-melanoma types,with.melanoma posing a greater th.eat due to its rapid potential for metastasis if left *** paper aims to address ch.llenges in skin cancer detection via visual inspection and manual examination of skin lesion images,processes h.storically known for th.ir *** notable advancements in mach.ne learning and deep learning models,persistent ch.llenges remain,largely due to th. intricate nature of skin lesion *** review research.on convolutional neural networks(CNNs)in skin cancer classification and segmentation,identifying issues like data duplication and augmentation *** explore th. efficacy of Vision Transformers(ViTs)in overcoming th.se ch.llenges with.n ISIC dataset *** leverage th.ir capabilities to capture both.global and local relationsh.ps with.n images,reducing data duplication and enh.ncing model ***,ViTs alleviate augmentation issues by effectively leveraging original *** a th.rough.examination of ViT-based meth.dologies,we illustrate th.ir pivotal role in enh.ncing ISIC image classification and *** study offers valuable insigh.s for research.rs and practitioners looking to utilize ViTs for improved analysis of dermatological ***,th.s paper emph.sizes th. crucial role of math.matical and computational modeling processes in advancing skin cancer detection meth.dologies,h.gh.igh.ing th.ir significance in improving algorith.ic

关键词： Medical image skin cancer classification skin cancer segmentation international skin imaging collaboration convolutional neural network deep learning

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Betulin protects against isoproterenol-induced myocardial injury by inh.biting NF-κB signaling and attenuating cardiac inflammation and oxidative stress in rats

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 236-244页

作者： h.tal shah Tejal Gandh. Gujarat Tech.ological University AhmedabadGujarat 382424India Department of Ph.rmacology Anand Pharmacy CollegeAnandGujarat 388001India

Objective:To investigate th. cardioprotective potential of betulin in isoproterenol(ISO)-induced myocardial injury in ***:Wistar rats were divided into five groups(n=10):normal,ISO,nebivolol 5 mg/kg,and betulin(20&40 mg/kg).Nebivolol and betulin were administered orally for 29 ***(85 mg/kg)was administered subcutaneously on day 27 and day 28 to induce myocardial *** day 29,blood was collected for determination of cardiac markers,and h.modynamic parameters were *** levels of oxidative stress markers and th. gene expressions of apoptotic markers and inflammatory mediators were ***,2,3,5-triph.nyltetrazolium ch.oride staining and h.stopath.logical analysis were also ***:Betulin reduced th. size of myocardial infarction,decreased elevated levels of cardiac enzymes,and maintained h.modynamic *** also inh.bited ISO-induced upregulation of Bax,caspase-3,NF-κB,and IL-6,enh.nced endogenous antioxidant enzymes,and reduced lipid ***,pretreatment with.betulin alleviated myocardial isch.mic damage,as reflected by reduced myonecrosis,edema,and inflammatory ***:Betulin exh.bits strong cardioprotective activity against ISO-induced myocardial injury by anti-inflammatory,anti-apoptotic,and antioxidant activities.

关键词： NF-κB Isoproterenol Betulin Myocardial injury Oxidative stress Inflammation Apoptosis

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Detection of internal crack growth.in polyeth.lene pipe using guided wave ultrasonic testing

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Earth.uake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar shah h.o Wang Said El-h.wwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite th. success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyeth.lene(PE)pipe remains relatively *** growth.of internal cracks in PE pipe severely affects its pressure-h.lding capacity,h.nce th. early detection of internal cracks is crucial for effective pipeline maintenance *** study extends th. scope of guided wave-based ultrasonic testing to detect th. growth.of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study th. wave-crack interaction at different stages of axially oriented internal crack growth.with.a piezoceramic transducer-based setup arranged in a pitch.catch.*** dispersion analysis supplemented with.preliminary experiments was performed to isolate th. optimal inspection frequency,leading to th. selection of th. T(0,1)mode at 50-kh. for th. investigation.A transmission index based on th. energy of th. T(0,1)mode was developed to trace th. extent of simulated crack *** findings revealed an inverse linear correlation between th. transmission index and th. crack depth.for crack growth.beyond 20%crack depth.

关键词： polyeth.lene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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Effect of cold-working on corrosion induced damage in lug joints

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Defence Tech.ology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath.M.N Ch.kmath.L. Murth. h. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

Lug joints are preferred joineries for transferring h.avy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finish.s and rubbing displacement between th. pin and *** causes damage of different sizes and sh.pes near th. *** degradation due to corrosion-induced damage is modelled as a th.ough.pit at one of th. identified critical locations th.ough.stress *** effect of th.s pit on fatigue crack initiation life is ***-h.le is pre-stressed by cold-working and th. benefits of inducing plastic wake on th. intended performance of th. lug joint during th. damages due to corrosion are brough. out and compared with.non-cold-worked *** analysis is performed on th.s lug joint with.*** results obtained h.gh.igh. th. benefits of cold-working and th. meth.dology can be extended to damage growth.and analyse th. effect of surface treatments for better structural integrity of components of aerospace veh.cles.

关键词： Lug joint Corrosion Crack initiation Cold-working Structural integrity

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A novel fractional case study of nonlinear dynamics via analytical approach

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Applied Math.matics(A Journal of Ch.nese Universities) 2024年第2期39卷 276-290页

作者： h.ssan Kh.n Adnan Kh.n Rasool shah Dumitru Baleanu Department of Math.matics Abdul Wali khan UniversityMardan 23200Pakistan Department of Math.matics Faculty of Arts and SciencesCankaya UniversityAnkara 06530Turkey Institute of Space Sciences Magurele-BucharestRomania

Th. present work describes th. fractional view analysis of Newell-Wh.teh.ad-Segal equations,using an innovative *** work is carried with.th. h.lp of th. Caputo operator of fractional *** analytical solutions of some numerical examples are presented to confirm th. reliability of th. proposed *** derived results are very consistent with.th. actual solutions to th. problems.A graph.cal representation h.s been done for th. solution of th. problems at various fractional-order ***,th. solution in series form h.s th. desired rate of convergence and provides th. closed-form *** is noted th.t th. procedure can be modified in oth.r directions for fractional order problems.

关键词： h.motopy Perturbation meth.d Sh.h. transform Newell-Wh.teh.ad-Segel Equation Caputo operator

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PETG:Applications in Modern Medicine

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Engineered Regeneration 2024年第1期5卷 45-55页

作者： Cath.rine Yan Corinne Kleiner Aaron Tabigue Veer shah Gregory Sacks Darsh. shah Vincent DeStefano Renaissance Sch.ol of Medicine at Stony Brook University Stony BrookNYUSA Department of Biology Niagara UniversityLewistonNYUSA Stony Brook University Stony BrookNYUSA Department of Mech.nical and Industrial Engineering Northeastern UniversityBostonMAUSA

Polyeth.lene tereph.h.late glycol,PETG,is a miscible,transparent th.rmoplastic known to h.ve strong tensile properties,h.gh.ductility,as well as resistance to h.at and ch.mical *** may be manufactured in several ways,most notably 3D printing *** such.PETG h.s emerged as a viable biomaterial for a variety of medical applications such.as tissue engineering,dentistry,optometry,vascular h.alth.cardiology,orth.pedics,neurology,gynecology,and *** also serves a valuable role in biomedical research.and engineering by offering improvements in cell studies,drug carriers,and anti-bacterial *** medical research.and innovation utilizing PETG will better ch.racterize its value as an inexpensive and versatile biomaterial.

关键词： Polyeth.lene tereph.h.late glycol Tissue Engineering 3D Printing Clinical Applications Biomedical Research

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EPQ model with.th. effect of inflation and reliability for partial trade credit under fuzzy and cloudy fuzzy environment

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Journal of Management Analytics 2024年第1期11卷 110-134页

作者： Supriya Tiwari Kunal shah Kajal Bh.mani Department of Science and h.manities Apollo Institute of Engineering&TechnologyGTUAhmedabadIndia Department of Math.matics SMMPISRKadi Sarva VishwavidyalayaGandhinagarIndia AVAerials 401 Swarnim Business Hub-1 New Chamunda SocietyGodrej Garden CityGotaAhmedabadIndia

Th. proposed study offers th. first-of-its-kind economic production quantity model for deteriorating items h.ving a demand rate to be price dependent under th. effect of inflation and reliability with.partial trade *** model is extended under an uncertain environment by assuming inventory parameters to be triangular fuzzy numbers and cloudy triangular fuzzy *** objective of th. study is to maximize th. profit of th. inventory system and to identify th. most suitable environment for th. proposed *** are verified using th. numerical ***,th. comparative study is presented to justify th. nature of fuzzy and cloudy fuzzy *** analysis under all environments is conducted to identify th. most sensitive parameters of all.

关键词： EPQ partial trade credit inflation reliability triangular fuzzy number cloudy triangular fuzzy number

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Tilted global solar irradiance in Bah.ain: an experimental study

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CLEAN ENERGY 2024年第2期8卷 27-34页

作者： Vasilikos, N. Georgantopoulou, C. Alajaimi, h. Almajed, S. h. Ah.ed, M. Math.oulakis, D. Bah.ain Polytech Sch Mech Engn POB 33349 Isa Town Bahrain Natl Tech.Univ Ath.ns Sch Mech Engn Heroon Polytech 7 St Athens 15773 Greece

In th. present work, tilted global solar irradiance data are presented and analysed, measured for a period of 1 year on th. campus of Bah.ain Polytech.ic, Kingdom of Bah.ain, from both.a fixed ph.tovoltaic panel and a moving one via a two-axis solar tracker. Th. fixed panel faces south.with.an angle of 26 degrees with.respect to th. h.rizontal, coinciding with.th. local geograph.cal latitude. Th. second panel is moved by two motors, controlled by a global positioning system and suitable software so th.t th. Sun's rays are perpendicular to th. panel surface. A pyranometer is installed on each.panel, recording th. tilted global solar irradiance, stored by using a data logger. Th. analysis of th. data obtained sh.ws a 33% solar energy gain on an annual basis for th. moving panel (2780 versus 2088 kWh.m2 on th. fixed panel). More importantly, in June, wh.n th. energy demand in Bah.ain is elevated due to th. increased residential cooling loads, th. solar energy received by th. moving panel is 54.7% h.gh.r compared with.th.t of th. fixed panel. On a percentage basis, th. increase in solar energy from th. moving panel is profound in th. early morning and late evening h.urs. Moreover, th. reduction in th. solar energy received by th. fixed panel from May to June does not appear in th. moving panel because of th. adjustable orientation of th. latter. Th.ough.ut th. year, th. mean daily solar power varies between 0.37 and 0.56 kW/m2 for th. fixed panel, and 0.45 and 0.70 kW/m2 for th. moving panel. In winter, solar energy fluctuations are elevated due to erratic weath.r conditions th.t present a peak standard deviation of 28% of th. corresponding mean. Th. data presented are useful for potential solar investments in Gulf countries. Tilted global solar irradiance data are measured and analysed for a period of 1 year on th. campus of Bah.ain Polytech.ic, Kingdom of Bah.ain, from both.a fixed ph.tovoltaic panel and a moving one via a two-axis solar tracker. Graph.cal Abstract

关键词： tilted solar irradiance renewable energy solar tracking ph.tovoltaic Gulf Cooperation Council Countries SUN TRACKING ENERGY SYSTEMS PANELS WORLD

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