Miracle-dz/UniFAR-FTUs huggingface dataset:
Shock and harmonic response analysis of UAV nose landing gear system with air damper

Abstract This research presents a response analysis of a UAV nose landing gear system equipped with an air damper under shock and harmonic excitation. The study begins with dynamic modeling of the UAV landing gear system. The system dynamics consists of a main mass and a wheel mass that are connected to each other by a U-shaped landing gear. The U-shaped landing gear is modeled by a linear spring and dashpot element. The air damper is added to the landing gear to increase the damping. The air damper consists of an air balloon that is connected to the outside via an orifice hole and the connecting pipe. A serial connection of spring, mass, and dashpot elements describes the air damper dynamic model. The simulation study is conducted to evaluate the effect of the landing gear parameters variation on the UAV dynamic response under shock and harmonic excitation. The maximum acceleration and displacement response of the UAV body under shock load is greatly affected by the air balloon cross-sectional area (Aef ) and the stiffness of the U-shaped landing gear system (KL ). The harmonic response of the UAV body is evaluated from the ratio between the UAV body displacement amplitude and the base excitation amplitude under harmonic excitation. It is shown that the air balloon cross-sectional area (Aef ) and the connecting pipe length (lp ) have a significant effect on the UAV mass displacement ratio. The experimental study is conducted to validate the simulation results. It is shown that the experimental data can verify the simulation results.
Foliar Application of Auxin or Cytokinin Can Confer Salinity Stress Tolerance in Vicia faba L.

Soil salinity severely declines the availability of water and essential minerals to the plants, which hinders growth. The present study evaluates the potential roles of indole-3-acetic acid (IAA) and 6-benzyladenine (BA) for mitigating the adverse effects of soil-salinity in faba bean (Vicia faba L.). Plants were exposed to 150 mM NaCl stress and were sprayed with IAA (1.15 mM) or BA (0.9 mM). Our results revealed that foliar application of IAA or BA improved the growth traits of salinized faba bean due to the increased uptake of K+, Ca2+, and Mg2+ ions, accumulation of free amino acids, soluble sugars, and soluble proteins, and activity of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase. The principal component analysis (PCA) and heatmap clustering indicated that salinity-exposed plants exhibited lower growth and biomass production, which correlated with higher accumulation of Na+ and malondialdehyde. Moreover, electrophoretic patterns of protein showed new bands in IAA- or BA-treated salt-stressed plants, indicating that IAA or BA treatment can reprogram the metabolic processes to confer salinity tolerance. We also found that IAA has a greater capacity to ameliorate the salt stress than BA, although there is no significant difference in yield between these treatments. Finally, these findings can be helpful for a better understanding of IAA- and BA-mediated salt tolerance mechanisms and increasing production of faba bean in saline soils.
Acoustical characterization of nickel aluminide (Ni3Al) at low temperatures

Present research work deals with the acoustical characterization of Nickel Aluminide (Ni3Al) at low temperature region from 10K to 50K. Particularly, the Ultrasonic waves have been used as a Non-destructive testing (NDT) tool to characterize this Ni3Al. For this purpose, in our technique, the two parameters such as the nearest-neighbour distance and the hardness parameter is taken as two input parameters. Ultrasonic attenuation due to the cause of e-p (electron-phonon) interaction has been evaluated from 10K to 50K, for longitudinal as well as shear waves along <100> crystallographic direction and the elastic constants (second order) for this intermetallic alloy of nickel and aluminium is also evaluated in low temperature region and the obtained results have been discussed.
Effects of Zn and Mg Segregations on the Grain Boundary Sliding and Cohesion in Al: Ab Initio Modeling

The formation of Zn and Mg segregations at a tilt Σ5{013} <100> grain boundary (GB) in Al and the effects of these solutes on deformation behavior of polycrystalline Al were investigated using ab initio total energy calculations. Using a step-by-step modeling of the segregation process, we found that the formation of a thick segregation layer of Zn at the GB is energetically preferable, while the formation of an atomically thin segregation layer is expected in the case of Mg. To reveal the effect of segregation on the cohesive properties of Al GBs, we calculated the energy of cleavage decohesion and the shear resistance for GB sliding. We show that the segregation of Zn results in a substantial decrease in barriers for GB sliding, while the segregation of Mg increases the barriers. The results obtained allow us to explain experimental findings and demonstrate a strong relationship between chemical bonding of solute atoms, their segregation ability, and GB strength.
Procedural environment of public engagement: an induced recall experiment of local government employees

ABSTRACT This research (1) examines how employees’ recollections of public engagement are associated with their willingness for future engagement (WFE), (2) assesses whether employees’ discrete recollections are driven by their procedural environments, and (3) tests whether employees’ recollections interact with their perceptions of red tape in affecting WFE. We find that one’s procedural environment parameterizes the effect of episodic recall on a subject’s WFE. Qualitative evidence reveals the prominence of one’s procedural environment across groups, but in terms of helping the public navigate administrative burdens in the positive treatment group and rules that hinder the employees in the negative treatment group.
Strength analysis of composite plates with auxetic honeycomb at static bending by the finite element method

In this paper, three-layer composite plates with continuous outer layers and an auxetic honeycomb interlayer of the chiral type based on rotating circles with tangentially attached rods are modeled. The physical and mechanical properties of the D16 aluminum alloy were chosen as the material properties of the layers of the composite plates. In the course of modeling, the discretization and volume of honeycomb structures in composites were varied at a constant thickness of the layers. Under the conditions of static bending of composite plates, load values were determined, at which maximum stresses in composites were equated to the conditional yield strength. The problem was solved using the finite element method in the framework of the theory of elasticity. The aim of this work is to study the influence of the discretization parameter and volume of the auxetic honeycomb interlayer on the magnitudes of load at yield strength stresses for the proposed composite plates.
Graphene-based SERS for sensor and catalysis

Abstract Graphene has a unique regular hexagonal honeycomb carbon structure, which results in excellent photoelectric and chemical properties. Especially the plasmon coupling effect produced by the composite of graphene and metal nano-substrate has great research prospects. The hybrid substrate composed of metal nanoparticles and graphene can construct the surface-enhanced Raman scattering (SERS) sensors and catalytic devices with the help of SERS effect, which has great potential in medical monitoring, food inspection, and biomedical fields. Currently, with the rapid development of graphene-based SERS sensors and catalytic equipment, we recognize that it is necessary to provide new research results. In this review, we first reviewed the different synthetic methods of graphene and the improvement of preparation methods. Subsequently, we reviewed the enhancement mechanism and the latest research on the graphene-based SERS sensor. Finally, we summarized the research progress of graphene-based and SERS effect on catalytic reactions.
Optical traps for single cell analysis

In order to better understand the development and spread of cancer, the methods by which cells communicate and disseminate information must be closely examined. As such, membrane proteins are an important target in modern cancer research due to their role in cellular signalling cascades. Disruption of these cascades can lead to abnormal cell growth and the onset of cancer. Therefore, characterising the recruitment and action of such membrane proteins is a key facet of the Single Cell Proteomics (SCP) initiative. This thesis lays out work on the use of optical trapping methods to study membrane proteins on single cancer cells. Optical traps provide a sterile, versatile toolset to manipulate single cells, and have been used here to manipulate cells both directly and indirectly. Direct manipulation of cells is used force them into contact to characterise the behaviour of the second messenger protein kinase Cε (PKCε). Particular attention is given both to the stage of the growth cycle of cells during recruitment, and to the effects of free calcium in both facilitating the accumulation of PKCε, and cell-to-cell adhesion strength. The indirect manipulation of cells takes a different approach to the study of membrane proteins, through the use of “Smart Droplet Microtools” as sampling agents. Comprised of micron-sized lipid-coated droplets with either a solid or oil core, SDMs exchange material with the cellular membrane when brought into contact with it. These SDMs can simultaneously remove membrane proteins from multiple sites on the same cell, providing spatial selectivity of the target protein. The SDMs can then transport the proteins downstream to interface with other techniques for further analysis. This project details not only improvements in stability and efficiency of these SDMs, but also provides the first examples of the transfer of their cargo onto solid-supported lipid bilayers and antibody microarrays for readout.
Imaging through deconvolution with a spatially variant point spread function

We demonstrate a technique for restoring imagery using a computational imaging camera with a phase mask that produces a blurred, space-variant point spread function (PSF). To recover arbitrary images, we first calibrate the computational imaging process utilizing Karheunen-Loeve Decomposition, where the PSFs are sampled across the field of view of the camera system. These PSFs can be transformed into a series of spatially invariant "eigen-PSFs", each with an associated coefficient matrix. Thus the act of performing a spatially varying image deconvolution can be changed into a weighted sum of spatially invariant deconvolutions. After demonstrating this process on simulated data, we also show real-world results from a camera system modified with a diffractive waveplate, and provide a brief discussion on processing time and tradeoffs inherent to the technique.
Fabrication of circuits by multi-nozzle electrohydrodynamic inkjet printing for soft wearable electronics

Wearable electronic devices are evolving from current rigid configurations to flexible and ultimately stretchable structures. These emerging systems require soft circuits for connecting the various working units of the overall system. This paper presents fabrication of soft circuits by electrohydrodynamic (EHD) inkjet-printing technique. Multi-nozzle EHD printing head is employed for rapid fabrication of electric circuits on a wide set of materials, including glass substrate (rigid), flexible polyethylene terephthalate (PET) films, and stretchable thermoplastic polyurethane (TPU) films. To avoid the effects of substrate materials on the jettability, the proposed multi-nozzle head is equipped with integrated individual counter electrodes (electrodes are placed above the printing substrate). High-resolution circuits (50 ± 5 µm) with high electrical conductivity (0.6 Ω □−1) on soft substrate materials validate our well-controlled multi-nozzle EHD printing approach. The produced circuits showed excellent flexibility (bending radius ≈ 5 mm radius), high stretchability (strain ≈ 100%), and long-term mechanical stability (500 cycles at 30% strain). The concept is further demonstrated with a soft strain sensor based on a multi-nozzle EHD-printed circuit, employed for monitoring the human motion (finger bending), indicating the potential applications of these circuits in soft wearable electronic devices.
Adsorption of toxic Congo red dye from aqueous solution using untreated coffee husks: kinetics, equilibrium, thermodynamics and desorption study

ABSTRACT In this study, the potential of using dried coffee husk adsorbent is systematically evaluated by conducting batch studies involving various process parameters, such as initial pH, dye concentration, adsorbent dosage, particle size, electrolytes, and temperature for the removal of Congo red (CR) dye from aqueous solutions. The prepared adsorbent was characterised with Attenuated Total Reflection, Field Emission Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy, thermogravimetric, particle size, zero-point charge, Brunauer–Emmett–Teller surface area, and pore volume analysis. The maximum adsorption efficiency is obtained at an initial pH, 6, dye concentration, 50 mg L−1, adsorbent dosage, 10.5 g L−1, and adsorbent particle size, 89 µm. The kinetic rate constants and isotherm parameters were determined using various kinetic and isotherm models, respectively. The pseudo-second-order kinetic model gave a good fit to the experimental data at various dye concentrations. The adsorption mechanisms were described by intra-particle diffusion and Boyd plots. The overall rate of adsorption is controlled by external film diffusion of dye molecules. The experimental equilibrium data fit the Langmuir isotherm model with a maximum monolayer adsorption capacity (qmax) of 38.65 mg g−1 at 303 K. Thermodynamic studies were performed to evaluate the change in Gibbs free energy (ΔG), change in enthalpy (ΔH), and change in entropy (ΔS) of the adsorption process. Based on the thermodynamic analysis, the adsorption was found to be endothermic in nature, and the process was chemisorption, spontaneous and favoured at high temperatures. Desorption studies were conducted with various desorbing reagents in various runs and the maximum desorption efficiency (60.36% in third run) was determined using the solvent methanol. Reusability studies demonstrated that the prepared adsorbent was effective up to three runs of operation. These results show that waste coffee husks are cost-effective, eco-friendly bio-sustainable materials, and can be used for the removal of colour from synthetic dye wastewater.
Sustainable Development Policy and Renewable Energy in Poland

(1) Background: This article aims to answer the question of whether the Republic of Poland, by stipulating in the Constitution of 1997 the principle of sustainable development and ecological security, has created favourable conditions for the development of renewable energy. (2) Methods: The research is conducted using descriptive methods and—due to the legal nature of the publication and the crucial role played by the dogmatic method—it consists of the interpretation of legal acts and court decisions. (3) Results: Over the last few years, state authorities have introduced a number of regulatory and legal mechanisms to increase the stability of the operation of renewable energy sources, including the development of biomass or geothermal energy, as well as the development of energy clusters and cooperatives. This article characterises specific solutions and assesses their effectiveness. (4) Conclusions: The state authorities should take further specific actions aimed at achieving the sustainable development of the renewable energy sector in Poland. These actions should be primarily aimed at the use of huge resources of renewable energy sources, saving the consumption of energy resources, reducing the demand for final energy, gradually converting electricity production from coal to renewable energy sources (RES), and moving away from fossil fuels for heat production in favour of RES.
Impulse Buying Model for Business-to-Consumer E-Commerce in Saudi Arabia

E-commerce has been growing rapidly worldwide, and with the current COVID pandemic, consumers are relying on it. In Saudi Arabia, the online shopping has been improving but it has not reached its full potential. That is why the concept of Impulse buying is essential and should be applied in the Saudi e-commerce. Therefore the purpose of this research paper is to identify and analyse the factors that affect impulse buying, specifically the Business-to-Consumer type, in Saudi Arabia and how to improve the e-commerce sector. This study is done using a quantitative approach to achieve the purpose of this study. There were 290 respondents, (81.9%) respondents were female and (18.1%) respondents were male. The respondents were familiar with e-commerce and the definition of the IB, however, the majority had a minimum knowledge regarding the effect that IB can create to their purchase decisions. A quantitative approach was a suitable choice for deductive methods since the results can be used to be generalized on a larger population. A questionnaire-based survey was used to collect the data for finding relationships between the indicators and factors. It was found out that advertisement, impulsiveness, and promotion are the main factors that positively influence IB in Saudi Arabia, but the factors of income and comment did not have any effect on IB.
Long-term stability of hollow core to standard optical fiber interconnection

In this paper, we present results of long-term stability tests of a low-loss (<0.55 dB) hollow core fiber (HCF) to standard optical fiber interconnection prepared by modified gluing-based fiber-array technology. We measured insertion loss of three interconnected HCF samples over a period of 100 days at room temperature, observing a variation in insertion loss of less than 0.02 dB. Subsequently, we placed the HCF samples in a climatic chamber and heated to +85°C in four cycles. Maximum insertion loss variation of 0.10 dB was observed for HCF samples with angled 8° interconnections and only 0.02 dB for a HCF sample with a flat interconnection.
Effect of Lean Practices on Lead Time Reduction

Abstract: This article presents a study on the effect of Lean practices on lead time reduction. In this study, we have proposed the consideration of human, technical and environmental factors in the study of the impact of production scheduling and SMED on manufacturing lead time. Based on the fact that scheduling and SMED go well beyond a calculation function. From our point of view, it is preferable to broaden the field of study of this impact by going beyond the fields of mathematics, operational research and artificial intelligence. In this study, we propose to start from the idea that there are other factors that can influence the expected results, namely human, technical and environmental factors. To achieve this, we went through a literature review and then tried to validate our hypotheses through a quantitative study.
Capitalizing on the Potential of South African Indigenous Beef Cattle Breeds: A Review

Cattle populations arrived in Southern Africa almost 2000 years ago, brought by farming communities migrating southwards. For centuries, cattle have been an integral component of livestock production to meet the animal protein needs of a growing population and they are also important in many cultural and religious events, as repositories of wealth and signifiers of social status. Selection within these cattle populations led to the development of breeds such as the Nguni, Afrikaner and Drakensberger that are well adapted to the local production environment. Genetic information has been generated for most of these populations, providing new insights into their ancestry and indicating moderate levels of diversity and relatively low inbreeding. Indigenous cattle breeds are present in both the well-developed commercial sector as well as the developing South African livestock sector. These breeds have been included in several research studies, mostly focusing on their production and adaptive potential. Genetic improvement of the local cattle populations and breeds, which are often more resilient to local environmental conditions, has the potential to improve the productivity of the small-scale production developing sector and contribute to the alleviation of poverty.
A new apterous rove beetle genus (Coleoptera: Staphylinidae) from the Northern Andes with an assessment of its phylogenetic position

A remarkable new apterous genus of Xanthopygina beetles is described here as Ikaros gen. nov. The new genus includes three new species, I. apteros gen. et sp. nov. from Colombia, I. paramo gen. et sp. nov. from Colombia and I. polygonos gen. et sp. nov. from Venezuela. Phylogenetic analyses using molecular and morphological data were performed to assess the phylogenetic position of Ikaros gen. nov. and whether the three new taxa formed a monophyletic group. All analyses, including those with aptery-associated characters removed, strongly supported the monophyly of Ikaros gen. nov. The genus could not be confi dently resolved as a member of any of the existing genus-group lineages, likely due to a lack of morphological signal in the backbone of the tree. Further analyses, ideally with molecular data, are needed to determine the position of Ikaros gen. nov.
A low noise CMOS instrumentation amplifier for TMR-effect-based magnetic sensors

This paper presents a low [Formula: see text] noise CMOS single-ended output instrumentation amplifier (IA) for tunneling magnetic resistance (TMR) sensors. For high DC gain and linearity, the amplifier employs three-stage current-feedback topology. For high CMRR and PSRR, the first two stages employ fully differential input. To maintain stability and lower the power dissipation, the amplifier employs trans-conductance with capacitance feedback compensation (TCFC) topology. The amplifier employs chopping technology and continuous-time AC-coupled ripple reduction loop to reduce [Formula: see text] noise and chopping ripple. The whole chip is fabricated using 0.35 [Formula: see text]m CMOS-BCD technology and the total area is 1 mm2. Test result shows an input-referred noise power spectral density (PSD) of 14 nV/[Formula: see text] is achieved with 1 Hz [Formula: see text] corner. The bandwidth is larger than 50 kHz [Formula: see text] with 20 pF load capacitor. The total current is 300 [Formula: see text]A at 5 V supply.
Weight-based colour constancy using contrast stretching

One of the main issues in colour image processing is changing objects’ colour due to colour of illumination source. Colour constancy methods tend to modify overall image colour as if it was captured under natural light illumination. Without colour constancy, the colour would be an unreliable cue to object identity. Till now, many methods in colour constancy domain are presented. They are in two categories; statistical methods and learning-based methods. This paper presents a new statistical weighted algorithm for illuminant estimation. Weights are adjusted to highlight two key factors in the image for illuminant estimation, that is contrast and brightness. The focus was on the convex part of the contrast stretching function to create the weights. Moreover, a novel partitioning mechanism in the colour domain that leads to improvement in efﬁciency is proposed. The proposed algo-rithm is evaluated on two benchmark linear image databases according to two evaluation metrics. The experimental results showed that it is competitive to the statistical state of the art methods. In addition to its low computational cost, it has the advantage of improving the efﬁciency of statistics-based algorithms for dark images and images with low brightness contrast. Moreover, it is robust to camera change types.