bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Intrusion Identification of Hazardous Construction Areas Based on Machine Vision
Authors: Hu Rongyi , Li Feng , Wang Tingting , Fan Haifeng , Dong Long
Published: February 2023

The complex environment of power construction sites is prone to frequent accidents and many dangerous areas. Using advanced artificial intelligence technology to monitor these dangerous areas in real-time is the primary measure to improve construction safety. Given the problems of poor real-time monitoring and the low accuracy of traditional methods, this paper proposes a real-time monitoring method for dangerous areas based on YOLOv5 deep learning, and through the trained YOLOv5, the construction site is monitored in real-time. Timely warnings are issued for those entering dangerous area to avoid accidents. Verified by the actual data, the method is timely and effective with high identification accuracy.
Design of 3D inspection system of switch station with distributed photovoltaic connected to distribution network
Authors: Zhang Hua , Li Shilong , Ding Lijie , He Xingqi , Xie Tianxiang , Huang Yan
Published: February 2023

The power distribution network has many switch stations connected to distributed photovoltaics. However, the heating hazard, the partial discharge in the switchgear, and the operation conditions of those switch gears cannot be detected and identified by traditional methods in time. This paper designs a three-dimensional (3D) inspection system for those switch stations. An infrared window in the switchgear, an infrared thermal imager, and an ultrasonic partial discharge detector outside the switchgear are designed to monitor the switch station environment. Finally, with video analysis technology, the system can identify the operation condition of the switch station equipment. It is significant to monitor and manage the switch stations, thus the switch stations become safer and more reliable.
Dispersion chain of quantum mechanics equations
Authors: Perepelkin E E , Sadovnikov B I , Inozemtseva N G , Korepanova A A
Published: February 2023

Based on the dispersion chain of the Vlasov equations, the paper considers the construction of a new chain of equations of quantum mechanics of high kinematical values. The proposed approach can be applied to consideration of classical and quantum systems with radiation. A number of theorems are proved on the form of extensions of the Hamilton operators, Lagrange functions, Hamilton–Jacobi equations, and Maxwell equations to the case of a generalized phase space. In some special cases of lower dimensions, the dispersion chain of quantum mechanics is reduced to quantum mechanics in phase space (the Wigner function) and the de Broglie–Bohm «pilot wave» theory. An example of solving the Schrödinger equation of the second rank (for the phase space) is analyzed, which, in contrast to the Wigner function, gives a positive distribution density function.
Steerability criteria based on Heisenberg–Weyl observables
Authors: Lai Lemin , Luo Shunlong
Published: February 2023

Einstein–Podolsky–Rosen (EPR) steering is an intermediate form of nonlocality which interpolates between entanglement and Bell nonlocality. It has been shown that EPR steerable states are fundamental resources for one-sided device-independent quantum information tasks. Nevertheless, distinguishing quantum steerable states from the unsteerable ones in general cases remains a big challenge under active studies. The generalized Bloch representation of density matrices in terms of the Heisenberg observables is a useful tool for analyzing characteristics of quantum systems and plays an important role in quantum information. In this work, the role of this representation in detection of EPR steering is studied. More specifically, based on the correlation matrices of the Heisenberg–Weyl observables, a family of steerability criteria for arbitrary dimensional bipartite systems are proposed. A large class of Hermitian operators, which can conveniently witness steering in some scenarios, are further provided. Finally, these criteria are illustrated through several examples, are compared with some existing ones, and their power and advantages are exhibited in certain cases.
Comparative assessment on climate prediction from CMIP5 and CMIP6 models over Hulu Terengganu, Malaysia
Authors: Syahmi Wan Amirul , Tukimat Nurul Nadrah Aqilah
Published: February 2023

The uncertainties of climate change in the future year cause the contribution factors and greenhouse gasses (GHGs) effects on the local climates need to be revised. The development of new climate scenarios in the 6th Coupled Model Intercomparison Project (CMIP6) is consistent with the technological exploration and increment of GHGs dispersion compared to the consideration factors in CMIP5. The purpose of this study was to compare the performance of CMIP5 (based on Representative Concentration Pathways, RCPs) and CMIP6 (based on Shared Socioeconomic Pathways, SSPs) in simulating seasonal rainfall and estimating trends in Hulu Terengganu, Malaysia. The linear scaling (LS) method was used in this study to treat the gaps between observed and simulated results, and the climate trend was examined using the Mann-Kendall (MK) and Sen’s Slope tests. The results show that the SSPs scenario outperforms the RCPs in simulating historical rainfall (2015-2020) by producing a higher r value and a smaller percentage difference. According to the MK test, there was no significant trend in projected rainfall across all scenarios (2020-2099). Based on Sen’s Slope test, RCP 4.5 and RCP 8.5 show an increasing trend for all rainfall stations. However, all SSP scenarios show a declining trend in projected rainfall, with SSP1-2.6 producing the largest declining trend magnitude. In contrast, when compared to observed rainfall from the baseline period (1988-2017), the SSPs scenario indicates the potential for a greater increase in future annual rainfall projections than the RCPs scenario. All SSP scenarios show an increasing annual rainfall magnitude in 2040-2069 (Δ2050). However, the annual rainfall for SSP2-4.5 and SSP5-8.5 began to decrease in 2070-2099 (Δ2080). Meanwhile, RCP 2.6 has the greatest reduction in annual rainfall projections for both projected time periods when compared to other scenarios. It can be concluded that although all SSPs scenarios show a declining trend in projected rainfall from 2020 to 2099, the total annual rainfall projected for SSPs remains higher than RCPs in Δ2050 and Δ2080 periods.
Indoor Air Quality (IAQ) and Related Risk Factors for Sick Building Syndrome (SBS) at the Office and Home: A Systematic Review
Authors: Aziz Norsaffarina , Adman Mohammad Adam , Suhaimi Nurud Suria , Misbari Syarifuddin , Alias Ahmad Rizal , Aziz Azrina Abd , Lee Lim Fang , Khan Md Mobarak Hossain
Published: February 2023

The comfort and productivity of workers may be affected differently by the indoor air quality (IAQ) and related risk factors at the office and at home. Sick Building Syndrome (SBS) is one of the health issues usually faced by workers. SBS is generally associated with the time spent in a building, IAQ, and other related risk factors. The study reviewed papers published in journal articles and conferences regarding IAQ, environmental risk factors and SBS in the last ten years. The review employed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 items from two significant databases, Scopus and Web of Science. The review steps involved identification, screening, eligibility, data extraction and analysis. The study found that air quality in a building significantly influences work productivity and may contribute to SBS. Findings show that SBS symptoms are linked to various personal characteristics, sociodemographic, working environment and IAQ factors. The physical contaminants, chemical contaminants and ventilation rate have established relations with SBS symptoms. These findings can help to form interventions aiming to improve IAQ and the productivity of occupants.
The Influence of Adiabatic Heat and Combined Blast Load and Fire Loading on the Response of Mild Steel Plates
Authors: Razak N S A , Nik Mazlan N N A A , Hassan Z , Alias A
Published: February 2023

This paper study the influence of adiabatic heat and fire loading on the behaviour of unstiffened mild steel plates subjected to close-in blast loads using finite element (FE) analysis. A quarter-symmetry 3D FE model consists of the steel plate, clamps and bolts was developed using Abaqus/CAE. Classical plasticity model was used as the material model in the steel plate and bolts. The clamps were assumed as an elastic material. Temperature-material properties relationship according to Eurocode 3 and Masui model was assigned to the steel plate. Conwep function was used to simulate the blast loads. The influence of strain rates was considered in the steel plate using the Cowper-Symonds equation. The FE model of the unstiffened plates was verified and validated against experimental data from literature, where a good agreement was achieved. The results suggest the adiabatic heat in the steel plates does not significantly influence the behaviour of the steel plates in both temperature-material properties models. The study then investigated the effect of combined blast loads and fire loading on the response of steel plates. The fire loading was applied by increasing the temperature in the steel from 200 °C to 1000 °C. Excessive deformation and thinning of the plate at the central area of the plate was observed. The thinning at the central area is pronounce than the thinning of the plate at the boundary between the clamp and the steel plate. Hence, the FE analysis suggests that the failure might occur at the central area of the plate, which could suggest a tearing type of failure. This type of failure is common in plates subjected to close-in blast loads. Therefore, this study has shown that the effect of adiabatic heat is insignificant, and the combined blast-fire loading might cause a similar type of failure as in plates subjected to blast loads only.
Utilization of Eggshells Ash as Additive in Enhancing Physical Properties of Bitumen Binder
Authors: Syammaun Tamalkhani , Husaini  , Abdullah  , Isya Muhammad
Published: February 2023

The aim of this research is to evaluate the physical properties of bitumen binder incorporating eggshell ash (ESA). Using ESA in bitumen was investigated as an alternative, as an additive in potential paths to landfill disposal and for improving the service physical properties of bitumen binder. Four different contents of ESA (2%, 5%, 7%, and 10%) were used by weight of bitumen with a 60/70 penetration grade. Several laboratory tests, i.e., penetration, softening point, ductility, viscosity, and specific gravity, were conducted to check the performance of the ESA. The results showed that the specimens with higher ESA content had the largest values of softening point. In contrast, the softening point decreased as the ESA content decreased. The addition of ESA clearly shows the increase in viscosity. From the observations, it is evident that the addition of 5% of ESA has the potential to improve the performance of bitumen binder compared to other ESA percentages.
Characteristic of Asphalt Mixture using Fly Ash and Bottom Ash Substitution in Reducing Environment Pollution
Authors: Azka C.N. , Rani H.A. , Katami T.M.R.
Published: February 2023

One of the waste materials produced by industry activities is fly ash and bottom ash (FABA), it is produced by brick combustion waste. Fly ash and bottom ash waste is hazardous and toxic (B3) waste for it contains heavy metal oxides polluting the environment. Related to the condition, the output study of toxicity potential test carried out to coal ash in Nagan Raya PLTU (Electric Steam Power Plant) proving conversely. The coal ash of Nagan Raya PLTU is relatively safe to be used as construction material. The output explained that coal ash of Nagan Raya PLTU have adequate good potency to be utilized. One of coal ash potencies developed is the utilization asphalt mixture material including bottom ash as fine aggregate substitution and fly ash as filler substitution. The research aimed to find out the mixture characteristic by utilizing FABA for the road pavement of asphalt concrete layer (AC-WC) to reduce environment pollution and detect the appropriate proportion for the optimal utilization. The percentage of fine aggregate in the mixture must meet the requirement of binder as 5-15% to the weight, while the filler must meet the minimum of 75% to weight of filter pass No. 200 (0.075 mm). The test output of both mixtures by using bottom ash and fly ashin 15%-30% variation was different. The output is similar. Both of the output concluded that the optimum asphalt level was 5% and the variation of 30% bottom ash : 70% fine aggregate meet the requirement specification, while variation fly ash as subtitution Portland cement resulting that all the parameters meet the specification required by Bina Marga specification 2018.
Pedestrian Behaviour at Unsignalized Zebra Crossing: A Case Study in UMP Gambang Campus
Authors: Ismail Azlina , Yusof Liyana Mohamed , Razlan Intan Suhana Mohd
Published: February 2023

The interest toward promoting walking culture has been increased dramatically especially in many cities across the nation. This is also included universities worldwide that have started seeking ways to increase pedestrian activities. Hence, campus planners must address the mobility and accessibility needs of pedestrian in their communities to ensure safety, functionality and conducive living and learning environment. This study was conducted to evaluate the pedestrian perception and behaviour towards the unsignalized zebra crossing in campus environment. To achieve the objective of this study, the unsignalized zebra crossing in UMP Gambang campus was selected as study location. This study was conducted using a quantitative study by means of questionnaires distribution and pedestrian movement data collection. Then Average Index Method was performed to indicate the pedestrian perception towards the crossing facility performances. The result shows that the zebra crossing was efficient and safe from the respondent’s perspective. Other than that, gender and platoon significantly influenced the crossing speeds. The outcomes from this study were hoped to bring some understanding to the university on the pedestrian’s behaviour for future planning and pedestrian safety.
Assessment of tensile behaviour of plain weave fabric CFRP composites using acoustic emission technique and deep learning
Authors: Barile C , Casavola C , Pappalettera G , Paramsamy Kannan V
Published: February 2023

The applications of Carbon Fibre Reinforced Plastic (CFRP) composites in aerospace applications have increased exponentially in the last decade. CFRP composites are now replacing conventional materials used in high temperature applications. Different types and strategies of reinforcements are used in these composites to improve their applicability to high temperature applications. One of the reinforcement strategies that has been used frequently in the recent years is the plain weave fabric configuration of reinforcing fibres in polymer matrix. A comprehensive damage assessment is essential to evaluate the characteristics of these composites at elevated temperatures. The Acoustic Emission (AE) signals generated during the damage evolution stages are used for studying the damage evolution stages when the plain weave fabric composites are tested at temperatures close to their glass transition state. A new information-theoretic parameter, Lempel-Ziv (LZ) complexity and the deep learning neural network is used for understanding the damage evolution stages. Furthermore, the neural network is used for validating the utilization of LZ complexity as a potential AE parameter for damage classification applications. The results are promising with the damage classification strategy using LZ complexity exhibits an accuracy of 85.1% which is validated through the neural network.
Increased interaction between Ultra-High Molecular Weight Polyethylene fibres and epoxy matrices for advanced composite materials
Authors: Galvanetto E , Caporali S , Zonfrillo G , Gulino M S , Pugliese L , Vangi D
Published: February 2023

Ultra-High Molecular Weight Polyethylene (UHMWPE) fibre is considered as an excellent strengthening component due to its high specific stiffness and strength, good wear resistance, low coefficient of friction and great chemical resistance. However, very weak interfacial adhesion with resin has hampered the development of UHMWPE-based composites with high performance. With the aim of improving the interface adhesion properties, the surface of the fibres has been decorated with PE crystal by a suitable chemical treatment. Adhesion property has been examined by pull-out tests, while tensile tests have been performed to evaluate the strength of the fibre. Preliminary results indicate that, compared to unmodified UHMWPE fibres, the overall mechanical properties of the composite with treated UHMWPE fibres and epoxy resin have been greatly improved. Moreover, the applied treatment does not weaken the strength of the fibre. The study results imply that the modified fibres have a great potential for use as reinforcing elements in high-performance composites.
Influence of Core Cellular Structures on Collapse Mechanisms Maps of Sandwich Beams
Authors: Utzeri M , Morichelli L , Lattanzi A
Published: February 2023

The main advantage of 3D printing is manufacturing complex and innovative shapes which guarantee high mechanical properties. Therefore, it is necessary easily figure out the most suitable structure for the required design requirements. The well-known strategy to design sandwich panels is evaluating collapse maps as they determine the panel performances based on their geometrical features. The aim of this study is to update the traditional collapse maps by showing how the core shape can improve the sandwich beam performance. The collapse maps proposed are based on advanced analytical models than the traditional Gibson theories. The analytical modelling of the indentation phenomenon is based on Vlasov’s model. The analytical modelling of the bending phenomenon is based on the First Shear Order Theory. The overall panel stress and strain maps are computed superposing both effects. A composite sandwich panels with Gyroid core based are analyzed to verify the proposed model consistency. A core failure criterion is chosen by experimental testing evidence on the representative core structure. Once the computed stress state overtakes failure criterion ones, the critical load is defined. In the end, the model is exploited to compare the performances of four sandwich panels with cores based on different lattice structures.
A contribute to the development of a design procedure for space-born sandwich panels with CFRP skins and an aluminum core
Authors: Mancini E , Mussolin L , Palmieri M , Ambrosi G , Cianetti F
Published: February 2023

Composite sandwich panels have a vast heritage and are commonly employed in various fields. The space industry is not an exception and often space structures and experiments use this type of panels. This paper represents an effort toward the development of a design procedure for space-born sandwich panels. The here-presented work has been performed on a real test case: the structural sandwich panel of a scientific space mission. In this preliminary phase, classical methodologies were used to ensure the satisfaction of the mechanical requirements and for the minimization of the panel mass and dimensions. Tools such as Finite Element (FE) were employed to help with the design. Increasingly detailed models were developed and used to design the space panels. In addition, this work describes the future roadmap of the project.
A numerical study on the cold sprayability of carbon fibre reinforced composites
Authors: Heydari Astaraee A , Bagherifard S , Colombo C
Published: February 2023

One of the open questions in cold spraying on fibre reinforced composites is the optimal thickness of the top layer to provide a suitable base for successful deposition of the metallic particles and at the same time to hinder the probable damage of the fibres. In this study, a detailed finite element model is developed to study the deformation of a single Cu particle deposition on to polyether ether ketone (PEEK) substrate reinforced with carbon fibres. A PEEK layer with 30, 40 or 60 μm thickness was considered on the top surface of the composite. The particle impact velocity was varied in the range of 300-600 m/s to analyse its effects on the induced deformations as well as the structural integrity of the critical carbon fibres. It is believed that the proposed model can provide a helpful tool for predicting the optimal conditions in the metallization of polymers using the cold spray technique.
The use of fractional order statistics for estimating nonparametric confidence intervals for quantiles of the fatigue damage computed in service random loadings
Authors: Benasciutti D , Marques J M E
Published: February 2023

This paper deals with the statistical variability of fatigue damage in random loadings as caused by the inherent randomness of the loading. It examines the use of a nonparametric method based on fractional order statistics as a tool for constructing confidence intervals for the quantile of fatigue damage, regardless of the knowledge of the damage probability distribution. The approach here discussed relies on a statistical method existing in the literature. After a short review of this method, with also an emphasis on possible advantages and limitations, the paper presents a numerical benchmark, followed by a practical application to time-histories measured on a mountain-bike in off-road tracks. The paper concludes with some critical remarks and an outlook.
Development, realization and validation of a device for real-time monitoring of fatigue behavior
Authors: Palmieri M , Morganti F , Cianetti F
Published: February 2023

The health monitoring of mechanical components and systems is a technique known and applied for decades in almost all fields of engineering since it allows a drastic reduction of the risks associated with any unexpected failure of components and at the same time allows reducing the plant maintenance and management costs. Several monitoring techniques exists and all of them are based on the acquisition and processing on-field measurements aimed to evaluate possible changes in the behavior of the component. Among these, in recent years a method able to monitor in real-time the fatigue damage or the potential damage of a structure with few information has been developed. In this paper, this method, implemented and tested only numerically, has been implemented in an acquisition board, expressly developed, and its ability to operate in real-time by monitoring the failure of a real component subjected to random vibrations has been tested.
Strength of notched Ti-6Al-4V specimens not subjected to solution treatment and over-aging under cyclic loading
Authors: Arcieri E V , Baragetti S
Published: February 2023

Ti-6Al-4V alloy is a popular titanium alloy due to its high strength / density ratio, high toughness, superior corrosion resistance and good biocompatibility. After forming operations, Ti-6Al-4V is typically subjected to Solution Treatment and Over-Aging (STOA). Fatigue is one of the most frequent causes of failure in mechanical components. The prediction and optimization of the strength of structural components under cyclic loads therefore plays a strategic role and must take into consideration the presence of defects. The aim of the work is to investigate the axial fatigue behaviour of Ti-6Al-4V alloy not subjected to STOA in inert environment in the presence of notches. The experimental results agree well with the results obtained using the Haigh diagram.
DIC analysis of mechanical response of tooth aligners under simulated swallowing acts
Authors: Casavola C , Pappalettera G , Pappalettere C , Patronelli M , Renna G , Ciavarella D , Laurenziello M
Published: February 2023

In this work, the mechanical and deformation behavior of clear Polyethylene Terephthalate-glycol (PET-g) aligners, under cyclic loading was investigated using a full-field optical technique: the Digital Image Correlation. In particular, the PET-g aligners thermoformed from 0.88 mm thick discs, were subjected to cyclic compression tests for 13000 load cycles from 0 to 50 N in the atmospheric environment (~25°C). This number of cycles was chosen because it simulates, on average, the intraoral load associated with the swallowing acts that an aligner is subjected to during the time of use of 1 week. At the same time, the results from the analysis of hysteresis loops obtained by the DIC technique were compared with those obtained by the testing machine. The mechanical response of clear aligners was evaluated in terms of maximum displacement, energy loss and relative stiffness along the load direction to seven different stages of the 13000 load cycles. A comparable trend was found between the measurements obtained by Digital Image Correlation analysis and the analysis of the hysteresis loops obtained from the cyclic compression tests. Furthermore, the morphological features of the PET-g aligner at the end of the tests were analyzed by optical microscopy (OM). The OM analyses showed that the surface of PET-g aligner was affected by morphological variations such as high depressions and cracks.
Implementation of the Peak Stress Method for the automated FEA-assisted design of aluminium welded joints subjected to constant amplitude multiaxial fatigue loads
Authors: Visentin A , Campagnolo A , Simonaggio F , Meneghetti G
Published: February 2023

The Peak Stress Method (PSM) is a FE-oriented local approach to the fatigue strength assessment of welded structures subjected to fatigue loading. Starting from the peak stresses calculated at the V-notch tip nodes defining weld toes or the weld roots, the PSM defines an equivalent peak stress which allows to estimate the fatigue failure location and fatigue lifetime of welded structures, in compliance with appropriate fatigue design curves. An Ansys® Mechanical extension has been developed to achieve full automated implementation of the tasks and calculations necessary to apply the PSM to welded structures. The tool allows to identify and analyse all the V-notch tip edges of the structure and perform fatigue life estimation on each analysed node. As an output, fatigue life results can be visualized through dedicated tabular data, graphs and contour results generated over the edges of the model. In this work, common-to-complex 3D geometries taken from the literature and related to aluminium alloys welded joints subjected to uniaxial as well as multiaxial fatigue loads have been analysed by comparing two design approaches: (i) manual application of the PSM, (ii) automated implementation of the PSM. The tool developed in Ansys® Mechanical allows to significantly contain the time and effort required to analyse welded structures according to the PSM.
Numerical modelling of the mechanical behaviour of Aluminosilicate Glass: A comparison between two simulation approaches
Authors: Manes A , Tartaglia M N , Wang Z
Published: February 2023

This paper presents a comparison between two numerical methods for modelling the mechanical and failure behaviour of aluminosilicate glass: Cohesive Elements Method (CEM) and Finite Element Method coupled to Smooth Particle Hydrodynamics (FEM-SPH). The failure behaviours, provided by these two approaches, are herein compared under i) quasi-static tests on material coupons, ii) dynamic tests (compressive and tensile tests) also on material coupons and iii) structural impact loading conditions in which the ballistic perforation of aluminosilicate glass tiles due to the impact of a flat-nosed steel projectile are considered. Both methods provide comparable results under quasi-static loading conditions, while more significant differences arise in the ballistic impact part, in which some limitations of CEM are shown.
Experimental and postprocessing procedures for the response of sheet metals to high strain rate
Authors: Mirone G , Barbagallo R , Tedesco M M , De Caro D , Ferrea M
Published: February 2023

Metals subjected to high strain rates in Hopkinson bar testing remarkably increase their temperature, so that thermal and dynamic effects are always interleaved. Experimental procedures in such field are not clearly standardized and the most common methods for tensile testing and postprocessing cannot highlight some crucial aspects of the dynamic response of metals. When sheet metal specimens are tested instead of bulk specimens, the accurate derivation of the flow curves are further complicated due to intrinsic strain nonuniformities induced by the specimen geometry and to possible material anisotropy. The local strain peaks calculated by digital image correlation, together with the specimen elongation / shrinking evaluated on the deforming specimen by optical methods, deliver remarkably different estimates of the stress-strain curves and of the strain rate histories for the same given test. Such differences are discussed in this paper together with the assessment of the anisotropic response of the material at static, intermediate and high strain rates.
Computational modeling of confined blast waves with focus on interaction with structures
Authors: Shehu E , Lomazzi L , Giglio M , Manes A
Published: February 2023

Blast loading is a critical extreme loading condition for most engineering structures. Modeling such scenarios is challenging due to the intrinsic non-linearities. Recent numerical methods can capture the physics governing blast waves and their interaction with structures in a more accurate way than established empirical methods. This article is intended as a proof of concept that state-of-the-art CFD and FE software can be combined to set up high-fidelity uncoupled simulations. Computational fluid dynamics is exploited in this work to map the pressure field developed during a detonation reaction in a Eulerian domain. Then, such pressure time history is applied in the finite element framework to perform Lagrangian simulations. The methodology is used to compare the structural response of blast-loaded plates in fully confined environments to that in free-field scenarios. It turns out that confined blast waves are more severe than blast waves in unconfined scenarios, mainly due to the multiple reflections and residual quasi-static pressure. Moreover, on the one hand, the quasi-static pressure appears to contribute to further increasing the plate out-of-plane deflection, while on the other hand, it prevents plates from undergoing reverse buckling or oscillations around the initial equilibrium configuration. Experimental tests are required to provide further evidence about the latter contribution.
Ductility assessment of a 17-4PH steel through simple multiaxial tests
Authors: Cortis G , Broggiato G B , Cortese L
Published: February 2023

The present work summarizes the results of an experimental campaign aimed at assessing the ductility of a wrought 17-4PH steel alloy. A simple specimen reproducing multiaxial stress states through a universal testing machine is selected. A Finite Element Model (FEM) for each test is setup to extract the local values of stress and strain in the most critical point on the onset of failure. A Digital Image Correlation (DIC) technique is employed to assess the strain field estimated via FEM. The collected data are used to analyse the material ductility, calculating the triaxiality and deviatoric parameter at the fracture strain. The proposed tests fall in the range of low triaxialities, which are less investigated in the literature. The results obtained are compared with the prediction of a damage model, previously calibrated on the material through more conventional tests. The prediction accuracy of the damage model was fully confirmed by the outcome of the new tests. Eventually, the possibility of replacing some of the conventional tests used for calibration with the proposed specimen is explored.
MXene/chitosan/lignosulfonate (MCL) nanocomposite for simultaneous removal of Co(II), Cr(VI), Cu(II), Ni(II) and Pb(II) heavy metals from wastewater
Authors: Othman Zakarya , Mackey Hamish R , Mahmoud Khaled A
Published: February 2023

In this work, a novel Ti3C2T
x
MXene/chitosan/lignosulfonate adsorbent (MCL), was prepared via a facile decoration of Ti3C2T
x
MXene sheets with chitosan/lignosulfonate nanospheres as a renewable and biodegradable additive that can improve the biocompatibility and aqueous stability of MXenes. Chitosan/lignosulfonate nanospheres were stabilized on the surface of MXne sheets, endowing them with a variety of surface functionalities, high specific surface area, and antioxidant characteristics. The competitive adsorption of multi-metal systems revealed that MCL had a preferential adsorption affinity toward various heavy metal ions; the MCL removal efficiency for the quinary-metal ions adsorption followed a trend of Pb(II) > Cr(VI) ≈ Cu(II) > Ni(II) ≈ Co(II) in neutral pH conditions. A moderate reduction was observed for Cu(II) and Cr(VI) ions. For all metals, the kinetics data fitted well with the pseudo-second-order model, and the adsorption equilibrium was best described by the Langmuir model. The adsorption mechanism is suggested to be a synergic combination of electrostatic interaction, surface complexation, and ion exchange. The findings of this study provide a new approach for eco-friendly MXene surface modification and give a general pattern of metal pollutants interactions during adsorption.
Optical design of vertical edge Thomson scattering on HL-2M tokamak
Authors: GONG Shaobo , SHI Zhongbing , ZHOU Yixuan , ZHANG Tongchuan , GAO Jinming , ZHENG Dianlin , SUN Ping , YU Liming , CHEN Wei , ZHONG Wulyu , XU Min , DUAN Xuru
Published: February 2023

A vertical edge Thomson scattering (ETS) diagnostic system on HL-2M tokamak has been designed. The ETS system collects the scattered light from Nd:YAG laser (1064 nm, 2 J, 30 Hz, 15 ns). The laser beam propagates vertically through the plasma region and the polarization is parallel to the toroidal magnetic field. A special designed Galileo-type telescope with long Rayleigh length is applied to focus the laser size and ensure collimation. A group of double-Gaussian collection lenses image the 600 mm vertical scattered region onto rectangular fiber arrays with a spatial resolution of 10 mm. The 2.20 mm × 2.86 mm fiber optic bundle consists of 130 low hydroxyl (OH) 200/220 μm (core/cladding) diameter fibers with numerical aperture NA = 0.22, carrying the light to remotely located multi-channel polychromators. Effect of oblique incidence on narrow band filter has been analyzed. The designed electron temperatures range from 5 to 1000 eV and electron densities from 5 × 1018 to 1 × 1020 m−3.
Signatures of a sampling quantum advantage in driven quantum many-body systems
Authors: Tangpanitanon Jirawat , Thanasilp Supanut , Lemonde Marc-Antoine , Dangniam Ninnat , Angelakis Dimitris G
Published: February 2023

A crucial milestone in the field of quantum simulation and computation is to demonstrate that a quantum device can perform a computation task that is classically intractable. A key question is to identify setups that can achieve such goal within current technologies. In this work, we provide formal evidence that sampling bit-strings from a periodic evolution of a unitary drawn from the circular orthogonal ensemble (COE) cannot be efficiently simulated with classical computers. As the statistical properties of COE coincide with a large class of driven analog quantum systems thanks to the Floquet eigenstate thermalization hypothesis, our results indicate the possibility that those driven systems could constitute practical candidates for a sampling quantum advantage. To further support this, we give numerical examples of driven disordered Ising chains and 1D driven Bose–Hubbard model.
Probing the dynamics and coherence of a semiconductor hole spin via acoustic phonon-assisted excitation
Authors: Coste N , Gundin M , Fioretto D A , Thomas S E , Millet C , Mehdi E , Somaschi N , Morassi M , Pont M , Lemaître A , Belabas N , Krebs O , Lanco L , Senellart P
Published: February 2023

Spins in semiconductor quantum dots (QDs) are promising local quantum memories to generate polarization-encoded photonic cluster states, as proposed in the pioneering Lindner and Rudolph scheme (2009 Phys. Rev. Lett.
103 113602). However, harnessing the polarization degree of freedom of the optical transitions is hindered by resonant excitation schemes that are widely used to obtain high photon indistinguishability. Here we show that acoustic phonon-assisted excitation, a scheme that preserves high indistinguishability, also allows to fully exploit the polarization selective optical transitions to initialise and measure single spin states. We access the coherence of hole spin systems in a low transverse magnetic field and directly monitor the spin Larmor precession both during the radiative emission process of an excited state or in the QD ground state. We report a spin state detection fidelity of

94.7
±
0.2
%

granted by the optical selection rules and a

25
±
5

 ns hole spin coherence time, demonstrating the potential of this scheme and system to generate linear cluster states with a dozen of photons.
Occurrence of antibiotic resistance genes and potentially pathogenic bacteria in the Yangtze River tributary (Nanjing section) and their correlation with environmental factors
Authors: Rajasekar Adharsh , Vadde Kiran Kumar , Murava Raphinos Tackmore , Qiu Mengru , Guo Shuaizhi , Yu Tong , Wang Ruoqing , Zhao Cailin
Published: February 2023

Freshwater environments are vulnerable to emerging contaminants such as Antibiotic resistance genes (ARGs), and their occurrence is gaining more attention. However, the occurrence of ARGs along with potential pathogens is less explored. The current study aimed to evaluate the abundance of ARGs and explore bacterial communities for the presence of potential bacterial pathogens in water samples collected from a tributary to the Yangtze River in Nanjing. Twelve physico-chemical parameters were analyzed, followed by quantifying 10 ARGs targeting sulfonamide (sul1, sul2), tetracycline (tetG, tetM, tetQ), erythromycin (ermB), vancomycin (vanA, vanR), and streptomycin (strA, strB) using real-time PCR and bacterial diversity characterization using high-throughput 16 S rRNA sequencing. The results indicated poor water quality and high-level eutrophication in most sampling locations. sul1, sul2, and strB were dominant in the study area with average concentrations of 6.8, 7.1, and 6.5 Log10 gene copies/100 ml, respectively. Proteobacteria, Cyanobacteria, Bacteroidetes, and Actinobacteria were the main phyla detected in the study area, and genus-level analysis revealed the presence of eight potential pathogenic and ten fecal-associated bacterial genera at several locations in the study area. The distance-based Redundancy analysis indicated that total phosphorus, electrical conductivity, dissolved oxygen, total dissolved solids, ammonium-N (NH4
+-N), and chlorophyll a had significantly influenced the bacterial community composition in the monitored locations. Correlation analysis demonstrated that water temperature, pH, NH4
+-N, and total organic carbon were positively correlated with sul2, tetG, and vanR genes, indicating that these environmental parameters significantly affected the ARGs distribution pattern. Overall, our results provide valuable information regarding the occurrence of ARGs and potential bacterial pathogens in the study area; however, their co-existence highlights increased human health risks.
Embedding aligned nanofibrous architectures within 3D-printed polycaprolactone scaffolds for directed cellular infiltration and tissue regeneration
Authors: Meng Zijie , Mu Xingdou , He Jiankang , Zhang Juliang , Ling Rui , Li Dichen
Published: February 2023

Three-dimensional (3D) printing provides a promising way to fabricate biodegradable scaffolds with designer architectures for the regeneration of various tissues. However, the existing 3D-printed scaffolds commonly suffer from weak cell-scaffold interactions and insufficient cell organizations due to the limited resolution of the 3D-printed features. Here, composite scaffolds with mechanically-robust frameworks and aligned nanofibrous architectures are presented and hybrid manufactured by combining techniques of 3D printing, electrospinning, and unidirectional freeze-casting. It was found that the composite scaffolds provided volume-stable environments and enabled directed cellular infiltration for tissue regeneration. In particular, the nanofibrous architectures with aligned micropores served as artificial extracellular matrix materials and improved the attachment, proliferation, and infiltration of cells. The proposed scaffolds can also support the adipogenic maturation of adipose-derived stem cells (ADSCs) in vitro. Moreover, the composite scaffolds were found to guide directed tissue infiltration and promote nearby neovascularization when implanted into a subcutaneous model of rats, and the addition of ADSCs further enhanced their adipogenic potential. The presented hybrid manufacturing strategy might provide a promising way to produce additional topological cues within 3D-printed scaffolds for better tissue regeneration.
Will high-entropy carbides and borides be enabling materials for extreme environments?
Authors: Wang Fei , Monteverde Frederic , Cui Bai
Published: February 2023

The concept of multi-principal component has created promising opportunities for the development of novel high-entropy ceramics for extreme environments encountered in advanced turbine engines, nuclear reactors, and hypersonic vehicles, as it expands the compositional space of ceramic materials with tailored properties within a single-phase solid solution. The unique physical properties of some high-entropy carbides and borides, such as higher hardness, high-temperature strength, lower thermal conductivity, and improved irradiation resistance than the constitute ceramics, have been observed. These promising properties may be attributed to the compositional complexity, atomic-level disorder, lattice distortion, and other fundamental processes related to defect formation and phonon scattering. This manuscript serves as a critical review of the recent progress in high-entropy carbides and borides, focusing on synthesis and evaluations of their performance in extreme high-temperature, irradiation, and gaseous environments.
Production process networks: a trophic analysis
Authors: Hazan Aurélien
Published: February 2023

In this article, production process databases originating from environmental sciences, more specifically from life cycle inventory (LCI), are considered as bipartite directed random networks. To model the observed directed hierarchical connection patterns, we turn to recent development concerning trophic coherence. Extending the scope to include bipartite networks, we compare several LCI networks to networks from other fields, and show empirically that they have high coherence and belong to the loopless regime, or close to its boundary.
Synchronization of online social rhythms via avatar communications
Authors: Takano Masanori
Published: February 2023

In this study, we consider users’ online communication rhythms (online social rhythms) as coupled oscillators in a complex social network. Users’ rhythms may be entrained onto those of their friends, and macro-scale pattern of such rhythms can emerge. We investigated the entrainment in online social rhythms and long-range correlations of the rhythms using an avatar communication dataset. We indicated entrainment in online social rhythms to emerge if the strength of a new connection reaches a threshold. This entrainment spread via densely-connected clusters. Consequently, long-range correlations of online social rhythms extended to about 36% of the network, although offline social life naturally restricts online social rhythms. This research supports an understanding of human social dynamics in terms of systems of coupled oscillators.
Calibration of quantum decision theory: aversion to large losses and predictability of probabilistic choices
Authors: Kovalenko T , Vincent S , Yukalov V I , Sornette D
Published: February 2023

We present the first calibration of quantum decision theory (QDT) to a dataset of binary risky choice. We quantitatively account for the fraction of choice reversals between two repetitions of the experiment, using a probabilistic choice formulation in the simplest form without model assumption or adjustable parameters. The prediction of choice reversal is then refined by introducing heterogeneity between decision makers through their differentiation into two groups: ‘majoritarian’ and ‘contrarian’ (in proportion 3:1). This supports the first fundamental tenet of QDT, which models choice as an inherent probabilistic process, where the probability of a prospect can be expressed as the sum of its utility and attraction factors. We propose to parameterize the utility factor with a stochastic version of cumulative prospect theory (logit-CPT), and the attraction factor with a constant absolute risk aversion function. For this dataset, and penalising the larger number of QDT parameters via the Wilks test of nested hypotheses, the QDT model is found to perform significantly better than logit-CPT at both the aggregate and individual levels, and for all considered fit criteria for the first experiment iteration and for predictions (second ‘out-of-sample’ iteration). The distinctive QDT effect captured by the attraction factor is mostly appreciable (i.e. most relevant and strongest in amplitude) for prospects with big losses. Our quantitative analysis of the experimental results supports the existence of an intrinsic limit of predictability, which is associated with the inherent probabilistic nature of choice. The results of the paper can find applications both in the prediction of choice of human decision makers as well as for organizing the operation of artificial intelligence.