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Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma m.madelaire K.m.Laundal J.P.Reistad s.m.Hatch s.Gasparini s.J.Walker Birkeland Centre for space science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth ***,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by *** emissions and scattered sunlight can contribute to the background *** fully utilize such images in space science,background contamination must be removed to isolate the auroral *** we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the *** demonstrate the model by using the three far ultraviolet cameras on the Imager for magnetopause-to-Aurora Global Exploration(ImAGE)*** method can be applied to historical missions and is relevant for upcoming missions,such as the solar wind magnetosphere Ionosphere Link Explorer(smILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

Low-temperature NH_(3)-sCR performance of a novel Chlorella@mn composite denitrification catalyst

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Journal of Environmental sciences 2024年第3期137卷 271-286页

作者： Hengheng Liu Fengyu Gao songjin ko Ning Luo Xiaolong Tang Erhong Duan Honghong Yi Yuansong Zhou school of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China school of Environmental science and Engineering University of Science and Technology HebeiHebei 050018China Department of Chemistry Pyongyang University of ArchitecturePyongyangDemocratic People’s Republic of Korea

The synthesis process of conventional mn-based denitrification catalysts is relatively complex and *** this paper,a resource application of chlorella was proposed,and a Chlorella@mn composite denitrification catalyst was innovatively synthesized by electrostatic *** Chlorella@mn composite denitrification catalyst prepared under the optimal conditions(0.54 g/L mn^(2+)concentration,20 million chlorellas/mL concentration,450℃ calcination temperature)exhibited a well-developed pore structure and large specific surface area(122 m^(2)/g).Compared with mnOx alone,the Chlorella@mn composite catalyst achieved superior performance,with~100%NH_(3)selective catalytic reduction(NH_(3)-sCR)denitrification activity at 100-225℃.The results of NH_(3)temperature-programmed desorption(NH_(3)-TPD)and H_(2)temperature-programmed reduction(H_(2)-TPR)showed that the catalyst had strong acid sites and good redox *** potential testing showed that the electronegativity of the chlorella cell surface could be used to enrich with mn^(2+).X-ray photoelectron spectroscopy(XPs)confirmed that Chlorella@mn had a high content of mn^(3+)and surface chemisorbed ***-situ diffuse refectance infrared Fourier transform spectroscopy(in-situ DRIFTs)experimental results showed that both Langmuir-Hinshelwood(L-H)and Eley-Rideal(E-R)mechanisms play a role in the denitrification process on the surface of the Chlorella@mn catalyst,where the main intermediate nitrate species is monodentate *** presence of sO_(2)promoted the generation and strengthening of Bronsted acid sites,but also generated more sulfate species on the surface,thereby reducing the denitrification activity of the Chlorella@mn *** Chlorella@mn composite catalyst had the characteristics of short preparation time,simple process and low cost,making it promising for industrial application.

关键词： Chlorella@mn catalyst NH_(3)-sCR Poisoning resistance Reaction mechanism Infuence of sO_(2)

Hydrogels for active photonics

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microsystems & Nanoengineering 2024年第1期10卷 1-16页

作者： Byoungsu ko Nara Jeon Jaekyung Kim Hyunjung Kang Junhwa seong suhyeon Yun Trevon Badloe Junsuk Rho Department of mechanical Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Graduate school of Artificial Intelligence Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea POsCO-POsTECH-RIsT Convergence Research Center for Flat Optics and metaphotonics Pohang 37673Republic of Korea

Conventional photonic devices exhibit static optical properties that are design-dependent,including the material’s refractive index and geometrical ***,they still possess attractive optical responses for applications and are already exploited in devices across various *** photonics has emerged as a promising solution in the field of active photonics by providing primarily deformable geometric parameters in response to external *** the past few years,various studies have been undertaken to attain stimuli-responsive photonic devices with tunable optical ***,we focus on the recent advancements in hydrogel-based photonics and micro/nanofabrication techniques for *** particular,fabrication techniques for hydrogel photonic devices are categorized into film growth,photolithography(PL),electron-beam lithography(EBL),and nanoimprint lithography(NIL).Furthermore,we provide insights into future directions and prospects for deformable hydrogel photonics,along with their potential practical applications.

关键词： lithography photonics attractive

Leveraging User-Generated Comments and Fused BiLsTm models to Detect and Predict Issues with mobile Apps

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Computers, materials & Continua 2024年第4期79卷 735-759页

作者： Wael m.s.Yafooz Abdullah Alsaeedi Department of Computer science College of Computer Science and EngineeringTaibah UniversityMedina42353Saudi Arabia

In the last decade, technical advancements and faster Internet speeds have also led to an increasing number ofmobile devices and users. Thus, all contributors to society, whether young or old members, can use these mobileapps. The use of these apps eases our daily lives, and all customers who need any type of service can accessit easily, comfortably, and efficiently through mobile apps. Particularly, saudi Arabia greatly depends on digitalservices to assist people and visitors. such mobile devices are used in organizing daily work schedules and services,particularly during two large occasions, Umrah and Hajj. However, pilgrims encounter mobile app issues such asslowness, conflict, unreliability, or user-unfriendliness. Pilgrims comment on these issues on mobile app platformsthrough reviews of their experiences with these digital services. scholars have made several attempts to solve suchmobile issues by reporting bugs or non-functional requirements by utilizing user ***, solving suchissues is a great challenge, and the issues still exist. Therefore, this study aims to propose a hybrid deep learningmodel to classify and predict mobile app software issues encountered by millions of pilgrims during the Hajj andUmrah periods from the user perspective. Firstly, a dataset was constructed using user-generated comments fromrelevant mobile apps using natural language processing methods, including information extraction, the annotationprocess, and pre-processing steps, considering a multi-class classification problem. Then, several experimentswere conducted using common machine learning classifiers, Artificial Neural Networks (ANN), Long short-Termmemory (LsTm), and Convolutional Neural Network Long short-Term memory (CNN-LsTm) architectures, toexamine the performance of the proposed model. Results show 96% in F1-score and accuracy, and the proposedmodel outperformed the mentioned models.

关键词： mobile apps issues play store user comments deep learning LsTm bidirectional LsTm

Complexed amino acid minerals ***-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： marcos J.B.santos maria C.m.m.Ludke Leandro m.silva Carlos B.V.Rabello mércia R.Barros Fabiano s.Costa Clariana s.santos Jamille s.s.Wanderley Department of Animal science Rural Federal University of PernambucoRecifePEBrazil Department of Veterinary science Rural Federal University of PernambucoRecifePEBrazil

The present study was to evaluate the effect of trace minerals(Zn,mn,and Cu)from complexed amino acid minerals(ZmCAA)and bis-glycinate chelated minerals(ZmCGly)in laying hen diets on performance,internal and external egg quality,yolk mineral deposition,intestinal morphometry,and bone *** 78 to 98 weeks of age,400 White LsL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per *** were distributed in a 2×2 factorial arrangement using either Zn,mn,and Cu of ZmCAA or ZmCGly source at 2 levels:low(20,20,and 3.5 mg/kg of Zn,mn,and Cu,respectively)or high(40,40,and 7 mg/kg of Zn,mn,and Cu,respectively).The analysis of variance was performed,and in cases where differences were observed,the means were compared using Tukey?s test(Psource and level of trace mineral supplementation had a significant impact on the performance of laying *** fed ZmCAA had higher egg production(P=0.01),egg weight(P=0.02),egg mass(P=0.01),and lower feed conversion ratio(P=0.05)compared to those fed *** ZmCAA supplementation showed higher albumen height(P=0.01),albumen weight(P=0.01),and eggshell thickness(Psition of Zn(Pmn(Ps greater for hens received *** weight(P=0.04)and bone densitometry(PmCAA *** the small intestine,ZmCAA resulted in longer villi(P=0.02)and shorter crypt depth(P=0.01)in the *** and ileum measurements were influenced by the level and source of trace minerals(Ps fed ZmCAA exhibited superior performance,egg quality,deposition of trace minerals in the egg yolk,and bone density compared to hens fed *** this study,older laying hens supplemented with ZmCAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates metal-amino acids Radiodensity Trace minerals

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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 *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** 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 ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** 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 *** 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 *** 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 *** 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 *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** 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

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

Evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 713-726页

作者： m.A.Najafgholipour s.Heidarian Radbakhsh E.Erfani Department of Civil and Environmental Engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the Opensees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.sardar m.D.Hossain m.s.sikder m.N.I.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material science Division Atomic Energy CentreDhaka1000Bangladesh

spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FEsEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(Vsm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FEsEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry H.m.s.El-Bassiouny m.m.s.Abdallah m.s.sadak Botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(sNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of sNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of sNP also decreased H_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid sodium nitroprusside Antioxidant enzymes Yield