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Journal of systems science and systems Engineering 2024年第2期33卷 187-206页

作者： Mintu Kumar Himani Pant s.B.singh Department of Mathematics statistics and Computer science G.B.Pant University of AgricultureTechnologyPantnagarUttarakhandIndia

Uncertainty is an important factor that needs to be considered while analyzing the performance of any engineering system.In order to quantify uncertainty,fuzzy set theory is frequently used by most of researchers,including energy system experts.According to the classical reliability theory,component lifetimes have crisp parameters,but due to uncertainty and inaccuracy in data,it is sometimes very difficult to determine the exact values of these parameters in real-world systems.To overcome this difficulty in the current research,failure and repair rates were taken as triangular fuzzy numbers to determine the fuzzy availability of a system undergoing calendar-based periodic inspection subject to multiple failure modes(FMs).It was assumed that each component in the system had an exponential failure rate and repair rate with fuzzy parameters.system FMs were explicitly taken into account when a functional state of the system was considered.Each FM had a random failure time.On the occurrence of any failure,a random time was selected for the relevant corrective repair work.The proposed research was studied for one of the major sources of green energy,namely a wind turbine system wherein all the derived propositions have been implemented on it.

关键词： Fuzzy reliability fuzzy availability wind turbine system multiple failure modes triangular fuzzy number

A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： Muhammed s.PARANCHEERIVILAKKATHIL Jafar s.PILAKKADAN Rafic M.AJAJ Mohammadreza AMOOZGAR Davood AsADI Yahya ZWEIRI Michael I.FRIsWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies Morphing aircraft shape morphing Flight dynamics Aeroelasticity

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Genes & Diseases 2024年第3期11卷 66-68页

作者： Aswathi N Jincy M.Jose sreelata B.Nair Prabha s.N Pappachan s Department of Medical Genetics Lifeline Super Specialty HospitalPathanamthittaKerala 691523India Lifeline super specialty Hospital PathanamthittaKerala 691523India

Alagille syndrome(ALGs;OMIM#118450)is a highlyvariable,multi-systemic,autosomal dominant disorder,caused by mutations in the Jagged Canonical Notch Ligand 1(JAG1)gene(20p12.2)or in the Neurogenic locus notch homolog protein 2(NOTCH2)gene(1p13).^(1)It primarily affects the liver,heart,eyes,face,kidney,skin,vertebrae,and skeleton.^(1,2)The JAG1 gene has 26 exons and about 90%of the ALGs cases result from pathogenic variants in the JAG1 and around 7%of cases have deletions in chromosome 20 that include this gene.

关键词： JAG1 cases Notch

Data-Driven Learning Control Algorithms for Unachievable Tracking Problems

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IEEE/CAA Journal of Automatica sinica 2024年第1期11卷 205-218页

作者： Zeyi Zhang Hao Jiang Dong shen samer s.saab the school of Mathematics Renmin University of ChinaBeijing 100872China IEEE the school of Engineering Lebanese American UniversityByblos 2038Lebanon

For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best approximation.subsequently, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete information.To address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain design.The input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings.

关键词： Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems

Interactivity software tools for teaching in ophthalmology

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Annals of Eye science 2024年第1期9卷 10-23页

作者： Jesús Barrio-Barrio Department of Ophthalmology Navarra University Clinic HospitalNavarra Institute for Health ResearchIdiSNAPamplonaSpain

The use of interactive audience software,such as audience response systems(ARs),in medical education has become increasingly popular in recent years.This technology allows instructors to engage students in real time,encouraging active participation and promoting effective learning.The benefits of interactive audience software in medical education include increased student engagement,promotion of active learning,and enhanced learning outcomes.However,there are also several challenges to its implementation,including technical difficulties,careful planning and preparation,over-reliance on technology,and ethical concerns related to privacy and data security.The cost of implementing interactive audience software may also be a barrier for some institutions.This paper specifically reviews six interactive software platforms,including socrative,Quizizz,Pear Deck,slido,Wooclap and ClassPoint.These platforms allow for real-time assessment of student understanding,feedback,and participation.They also enable instructors to adjust their teaching strategies based on student responses and feedback.Overall,interactive audience software has shown great potential to enhance learning and engagement in medical education.It is important for instructors to carefully consider the benefits and challenges of its implementation.While the cost of implementing interactive audience software may be a barrier for some institutions,there are free and low-cost options available.

关键词： Interactive audience software mobile software audience response systems(ARs) medical education

An in vitro demonstration of a passive,acoustic metamaterial as a temperature sensor with mK resolution for implantable applications

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Microsystems & Nanoengineering 2024年第1期10卷 41-54页

作者： Lucrezia Maini Vicente Genovés Roman Furrer Nikola Cesarovic Christofer Hierold Cosmin Roman Micro-and Nanosystems Department of Mechanical and Process EngineeringETH ZurichTannenstrasse 38092 ZurichSwitzerland. Translational Cardiovascular Technology Department of Health Science and TechnologyETH ZurichLeopold-Ruzicka-Weg 48093 ZurichSwitzerland. Transport at Nanoscale Interfaces Swiss Federal Laboratories for Materials Science and TechnologyEMPAÜberlandstrasse 1298600 DübendorfSwitzerland Department of Cardiothoracic and Vascular surgery Deutsches Herzzentrum der Charite(DHZC)13353 BerlinGermany

Wireless medical sensors typically utilize electromagnetic coupling or ultrasound for energy transfer and sensor interrogation.Energy transfer and management is a complex aspect that often limits the applicability of implantable sensor systems.In this work,we report a new passive temperature sensing scheme based on an acoustic metamaterial made of silicon embedded in a polydimethylsiloxane matrix.Compared to other approaches,this concept is implemented without additional electrical components in situ or the need for a customized receiving unit.A standard ultrasonic transducer is used for this demonstration to directly excite and collect the reflected signal.The metamaterial resonates at a frequency close to a typical medical value(5 MHz)and exhibits a high-quality factor.Combining the design features of the metamaterial with the high-temperature sensitivity of the polydimethylsiloxane matrix,we achieve a temperature resolution of 30 mK.This value is below the current standard resolution required in infrared thermometry for monitoring postoperative complications(0.1 K).We fabricated,simulated,in vitro tested,and compared three acoustic sensor designs in the 29-43℃(~302-316 K)temperature range.With this concept,we demonstrate how our passive metamaterial sensor can open the way toward new zero-power smart medical implant concepts based on acoustic interrogation.

关键词： passive resolution utilize

Paraneoplastic retinopathies: an update on pathogenesis, diagnosis and management

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Annals of Eye science 2024年第1期9卷 34-42页

作者： Akshay s.Thomas Tennessee Retina NashvilleTNUSA

The paraneoplastic retinopathies are a heterogeneous group of disorders with significant visual consequences occuring in the setting of a systemic malignancy.These conditions may be characterized by the presence of antiretinal antibodies and may predate or follow the diagnosis of an underlying malignancy.Herein I review the clinical findings,pathophysiology,laboratory testing and management of the paraneoplastic retinopathies:cancer-associated retinopathy(CAR),melanoma-associated retinopathy(MAR),bilateral diffuse uveal melanocytic proliferation(BDUMP)and paraneoplastic vitelliform maculopathy(PVM).The pathophysiology of the paraneoplastic retinopathies varies from molecular mimicry resulting in anti-retinal antibody production(CAR,MAR)to relases of soluble factors either by the primary tumor(BDUMP)and/or immune system in response to the primary tumor(PVM)which result in retinal and/or retinal pigment epithelium dysfunction.For each condition,structural and functional multimodal retinal testing can be helpful in establishing the diagnosis.Treatment for the paraneoplastic retinopathies involves a combination of treating the underlying malignancy plus additional local and/or systemic immunosuppressive agents though no systemic therapeutic protocols exist.Despite these interventions,the retinopathy may be progressive or the retinopathy may be a harbinger of poor survival.Nevertheless,prompt diagnosis may help identify an underlying malignancy earlier and may thus improve cancer-related survival.

关键词： Paraneoplastic retinopathy bilateral diffuse uveal melanocytic proliferation(BDUMP) cancer-associated retinopathy(CAR) vitelliform

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.FAZEL A.M.sHAFEI s.R.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic systems.This is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases considerably.Moreover,the human leg bones that are involved in walking are supported by viscoelastic muscles and ligaments.Therefore,for achieving more exact results,it is essential to model the robot links with viscoelastic properties.To this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of motion.The most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational force.The extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned goal.To overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue problem.By solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are determined.The effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of robotic systems are also studied.The findings o

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri E Vijayatha V Ramasubramanian s Thiyagarajan P Department of science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction technique.For each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and dopants.Upconversion luminescence emissions of green and red colour were detected for the synthesized phosphors.The changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared phosphors.In the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green emission.The rare-earth Er/Ho doped KYbF4shows strong red emission compared to other hosts.KYF_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 mW.Downshifting photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)sample.This study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates

Astrophysical s-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： s.B.Dubovichenko A.s.Tkachenko R.Ya.Kezerashvili N.A.Burkova B.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate school and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying resonances.The investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 transition.We calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·b.The important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is found.The reaction rate is calculated and compared with the existing rates.It has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the CNO Gamow windows,especially at low temperatures.We estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from Phys.Rev.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=1.3.We present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle