bluuebunny/crossref_metadata_2025 huggingface dataset:
On Lusztig's map for spherical unipotent conjugacy classes in disconnected groups
Authors: Cesari Martina Costa , Costantini Mauro
Published: February 2023

Let be a simple algebraic group over an algebraically closed field and let be a graph‐automorphism of . We classify the spherical unipotent conjugacy classes in the coset . As a by‐product, we show that J.‐H. Lu's characterization in characteristic zero of spherical conjugacy classes in by the dimension formula also holds for spherical unipotent conjugacy classes in in positive characteristic. If has order 2, we provide an alternative description of the restriction to spherical unipotent conjugacy classes in , of Lusztig's map from the set of unipotent conjugacy classes in to the set of twisted conjugacy classes of the Weyl group of . We also show that a twisted conjugacy class in the Weyl group has a unique maximal length element if and only if it has maximum in the Bruhat order (a result previously proved by X. He).
Sharp weak‐type estimates for maximal operators associated to rare bases
Authors: Hagelstein Paul , Oniani Giorgi , Stokolos Alex
Published: February 2023

Let denote a nonempty translation invariant collection of intervals in (which we regard as a rare basis), and define the associated geometric maximal operator by
We provide a sufficient condition on so that the estimate
is sharp. As a corollary, we obtain sharp weak‐type estimates for maximal operators associated to several classes of rare bases including unions of one‐parameter infinite families of Córdoba, Soria, and Zygmund‐type bases.
Monodromy of four‐dimensional irreducible compatible systems of Q$\mathbb {Q}$
Authors: Hui Chun Yin
Published: February 2023

Let be a totally real field and a natural number. We study the monodromy groups of any ‐dimensional strictly compatible system of ‐adic representations of with distinct Hodge–Tate numbers such that is irreducible for some . When , , and is fully symplectic, the following assertions are obtained.

The representation is fully symplectic for almost all .

If in addition the similitude character of is odd, then the system is potentially automorphic and the residual image has a subgroup conjugate to for almost all .
The complex function of macrophages and their subpopulations in metabolic injury associated fatty liver disease
Authors: Subramanian Pallavi , Chavakis Triantafyllos
Published: February 2023

Non‐alcoholic fatty liver disease (NAFLD), recently also defined as metabolic dysfunction‐associated fatty liver disease (MAFLD), is a major health problem, as it affects ∼25% of the population globally and is a major cause of hepatic cirrhosis and thereby liver failure, as well as hepatocellular carcinoma. MALFD comprises a broad range of pathological conditions in the liver, including simple fat accumulation (steatosis) and the more progressive non‐alcoholic steatohepatitis (NASH) that can lead to fibrosis development. Cells of innate immunity, and particularly macrophages, comprising the liver resident Kupffer cells and the recruited monocyte‐derived macrophages, play complex roles in NASH‐related inflammation and disease progression to fibrosis. Here, we discuss the recent developments with regards to the function of liver macrophage subpopulations during MAFLD development and progression.

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A Finite Element Based Comparative Study of Lumbosacral Pedicle Screw Fixation and Artificial Disc Replacement
Authors: Biswas Jayanta Kumar , Banerjee Anik , Mondal Nitesh , Rana Masud
Published: February 2023

The aim of this is to evaluate the biomechanical performance of double-level semirigid pedicle screw fixation and artificial intervertebral disc replacement in lumbar spine. Ti6Al4V and CFR-PEEK material are used for pedicle screw fixation and artificial disc replacement. In the present study, pedicle screw fixation and artificial intervertebral disc replacement are carried out between L3-L4-L5 regions under the application of moment 6,8,10 Nm and range of motion is compared during flexion, extension, and right-left lateral bending. Two-level pedicle screw fusion and total disc replacement are developed in the L3-L4-L5 of the lumber spine vertebrae. Carbon fiber reinforced (CFR-PEEK) and ultra-high molecular weight polyethylene (UHMWPE) are considered for the spinal fusion and the core part of the artificial disc respectively. Afterwards, applying the finite element analysis, it is detected that CFR-PEEK rod is able to increase range of motion at the implanted level in comparison to Ti6Al4V rod for both flexion–extension and lateral bending. In case of artificial intervertebral disc replacement hypermobility was observed. Hence, it is significant that rod material with CFR-PEEK is a better alternative for the treatment of degenerative diseases.
Manufacturing of Gallium Nitride Thin Films in a Multi-Wafer MOCVD Reactor
Authors: Jumaah Omar Dhannoon , Jaluria Yogesh
Published: February 2023

Gallium nitride (GaN) thin films have attracted considerable attention for manufacturing optical and electronic devices. They have wide bandgap and superb performance in these applications. The reliability and durability of optoelectronic devices depend on the quality of the GaN thin films. The metal-organic chemical vapor deposition (MOCVD) process is a common manufacturing technique for fabricating high-quality thin films. By manipulating the operating conditions and the reactor design, one can control the deposition rate and the uniformity of the thin film. In this paper, the manufacturing process for GaN thin films in a multi-wafer MOCVD reactor is simulated based on the three-dimensional computational model of an experimental system which provides data for validation as well as realistic design parameters. The reactor pressure and the flow rate of the precursor, trimethyl-gallium (TMG), significantly affect the deposition rate and film uniformity. The incursion of impurities in the deposition can be reduced by increasing the volumetric ratio of NH3 to TMG (V/III) and reducing the reactor pressure. The deposition rate and quality of the thin film are enhanced using an appropriate mixture of H2 and N2 as the carrier gas. The design of the inlet can also be varied to improve the utilization of metal-organic precursors and increase the deposition rate. This paper presents and discusses results on these aspects for this important manufacturing process. Thus, it leads to a better understanding of the basic mechanisms involved and provides guidelines for obtaining high deposition rates with high film quality in practical chemical vapor deposition reactors.
Validation of an Analytical Model for the Acoustic Impedance Eduction of Multicavity Resonant Liners by a High-Fidelity Large Eddy Simulation Approach
Authors: Giaccherini Simone , Pinelli Lorenzo , Marconcini Michele , Pacciani Roberto , Arnone Andrea
Published: February 2023

The massive growth of the air traffic during the last years is leading to stricter limitations on the noise emission levels radiated from aircraft engines. To face this issue, the installation of acoustic liners on the intake duct and the exhaust nozzles is a common strategy adopted to properly abate noise emissions coming from the fan, the compressor, the turbine, and the jet. In this context, the aim of the present article is to use high-fidelity large Eddy simulation (LES) to validate a multi-degree-of-freedom (MDOF) extension of the single-degree-of-freedom (SDOF) and double-degree-of-freedom (DDOF) analytical model provided by Hersh for impedance eduction of acoustic liners. First, the results of the original Hersh model are compared with LES calculations performed with the openfoam suite on a single-orifice and single-cavity layout (SDOF). Then the extension of the Hersh model to multicavity (MDOF) geometries by using a recursive formulation is presented. Finally, high-fidelity simulations are carried out for single-orifice and multicavity (MDOF) configurations to validate the method extension and to understand how resonant coupling and acoustic impedance are affected by multicavity resonant elements. The excellent agreement between the high-fidelity results and the analytical predictions for the single-cavity pattern confirms that the Hersh model is a useful formulation for a preliminary design of a SDOF acoustic liner. The model extension to MDOF configurations enables the designers to broaden the design space, and thus, a validated analytical method is strictly necessary to perform sensitivity studies to the multicavity geometrical parameters (i.e., facesheet thickness, cavities depth, porosity). Basically, a multicavity configuration makes the liner element resonate at different frequencies, leading to multiple absorption peaks in the audible range. In this way, the acoustic performance of the liner is extended to a wider frequency range, overcoming the limitations of a traditional SDOF configuration.
Fuzzy Logic Control-Based Charge/Discharge Equalization Method for Lithium-Ion Batteries
Authors: Wu Tiezhou , Xu Feng , Xu Siyun , Sun Shu
Published: February 2023

In this article, a grouping equalization circuit based on the single-ended primary inductor converter (SEPIC) circuit is proposed, which can transfer energy between any single cell or grouped cells. Compared with the traditional equalization circuits that transfer energy between adjacent cells, the SEPIC circuit can directly connect any two batteries that need to be equalized; the number of circuit equalization paths is calculated based on a directed graph and then used as a basis for grouping the batteries to improve the equalization efficiency. In the charging or discharging condition, the amount of charge remaining in the battery to be charged or discharged is used as the control variable for equalization, and intragroup equalization is completed before intergroup equalization starts. To ensure the equalization efficiency of the battery, the equalization current is controlled by fuzzy logic control (FLC). Taking ten single cells as an example based on the calculation of the number of equalization paths, two 5-cell groups can be confirmed as the optimal solution. Experiments were performed on matlab/simulink simulation platform, and the results show that compared with the traditional adjacent inductance equalization circuit, the equalization circuit proposed earlier reduces the time needed for equalization by 35.8%; compared with the traditional average difference method, in charging and discharging conditions, the FLC algorithm saves times by 20.5% and 31.3%, respectively, and energy loss is reduced by 9.1% and 5.5%, respectively, which verifies the feasibility of the proposed equalization scheme.
Multiphysics Simulations of Microwave Induced Damage Applied to Rock Samples of Varying Strength and Absorptivity
Authors: Allen J. B. , Patel R. R. , Taylor O.-D. S.
Published: February 2023

In this work, we show the development of a numerical model to investigate the 3D interactions between microwave radiation and basalt, granite, and sandstone rock samples. In particular, we assign sample heterogeneity based on the Weibull statistical distribution, and invoke a damage model for elemental tensile and compressive stresses based on the maximum tensile stress and the Mohr–Coulomb theories, respectively. Model implementation is facilitated by the use of comsol for use in coupling the electromagnetic, thermal, and solid displacement relations. Various parametric studies are conducted related to variable input power and waveguide port alignment, with model validation conducted with respect to damage resulting from a uniaxial compression test. The results indicate that relatively high induced temperatures will promote damage potential, but its impact must be placed within the context of the sample strength to quantify the true potential damage evolution of a given rock mass. As observed herein, a mechanically weaker rock may be prone to mechanical damage; however, it may also possess a relatively large relative permittivity, enabling it to absorb the least amount of microwave radiation thus yielding comparatively low overall damage profiles compared to a more mechanically competent rock mass.
Turbulent Anisotropy and Length Scale Variation Over Multiple Shaped Structure
Authors: Raushan Pankaj Kumar , Singh Santosh Kumar , Debnath Koustuv
Published: February 2023

The turbulent flow characteristics over bed-mounted three different cubical shape bluff bodies are examined experimentally in the water channel facility. The steady and fluctuating flow fields are investigated to analyze the effect of corner radius and shapes of the bluff body on turbulent flow structure, particularly in the wake region. It is found that the sharp corner region significantly impacts the flow separation and alters the characteristics of the shear-layer flow. In particular, the relatively suitable change in geometry resulted in a remarkable variation of the mean flow in the wake is observed. The anisotropic nature of flow is analyzed using the turbulence triangle for the different cubical structures. The variation of the turbulent length scales is presented in the near- and far-wake regions of the submerged obstacles.
Plio-Pleistocene deep-sea ventilation in the eastern Pacific and potential linkages with Northern Hemisphere glaciation
Authors: Yi Liang , Medina-Elizalde Martín , Tan Liangcheng , Kemp David B. , Li Yanzhen , Kletetschka Gunther , Xie Qiang , Yao Huiqiang , He Huaiyu , Deng Chenglong , Ogg James G.
Published: February 2023

Antarctic bottom water (AABW) production is a key factor governing global ocean circulation, and the present disintegration of the Antarctic Ice Sheet slows it. However, its long-term variability has not been well documented. On the basis of high-resolution chemical scanning of a well-dated marine ferromanganese nodule from the eastern Pacific, we derive a record of abyssal ventilation spanning the past 4.7 million years and evaluate its linkage to AABW formation over this period. We find that abyssal ventilation was relatively weak in the early Pliocene and persistently intensified from 3.4 million years ago onward. Seven episodes of markedly reduced ocean ventilation indicative of AABW formation collapse are identified since the late Pliocene, which were accompanied by key stages of Northern Hemisphere glaciation. We suggest that the interpolar climate synchronization within these inferred seven collapse events may have intensified global glaciation by inducing poleward moisture transport in the Northern Hemisphere.
High n-type and p-type conductivities and power factors achieved in a single conjugated polymer
Authors: Yu Zi-Di , Lu Yang , Wang Zi-Yuan , Un Hio-Ieng , Zelewski Szymon J. , Cui Ying , You Hao-Yang , Liu Yi , Xie Ke-Feng , Yao Ze-Fan , He Yu-Cheng , Wang Jie-Yu , Hu Wen-Bing , Sirringhaus Henning , Pei Jian
Published: February 2023

The charge transport properties of conjugated polymers are commonly limited by the energetic disorder. Recently, several amorphous conjugated polymers with planar backbone conformations and low energetic disorder have been investigated for applications in field-effect transistors and thermoelectrics. However, there is a lack of strategy to finely tune the interchain π-π contacts of these polymers that severely restricts the energetic disorder of interchain charge transport. Here, we demonstrate that it is feasible to achieve excellent conductivity and thermoelectric performance in polymers based on thiophene-fused benzodifurandione oligo(
p
-phenylenevinylene) through reducing the crystallization rate of side chains and, in this way, carefully controlling the degree of interchain π-π contacts. N-type (p-type) conductivities of more than 100 S cm
−1
(400 S cm
−1
) and power factors of more than 200 μW m
−1
K
−2
(100 μW m
−1
K
−2
) were achieved within a single polymer doped by different dopants. It further demonstrated the state-of-the-art power output of the first flexible single-polymer thermoelectric generator.
Historic climate change trends and impacts on crop yields in key agricultural areas of the prairie provinces in Canada: a literature review
Authors: Mapfumo Emmanuel , Chanasyk David S. , Puurveen Dick , Elton Shannon , Acharya Sachin
Published: February 2023

The objective of this literature review was to compile research findings on climate change and its impacts on crop production in Prairie Provinces of Canada. Our search strategy included finding primary literature articles from various databases. Seven articles reported increases in average and minimum air temperature over time in the Prairie Provinces of Canada. Increases in maximum air temperature were smaller than that for minimum air temperature. Growing degree days and corn heat units also increased over time, which has allowed for potential expansion of corn growth northwards. While overall increases in average annual precipitation and growing season precipitation have occurred in Canada between 1900 and 2021, western Canada showed increases in some regions but decreases in others. Off-season precipitation and snow cover duration in Canada have decreased since 1950. The number of frost-free days has increased across Canada, on the Prairies and southern Saskatchewan since 1900. Annual snowfall has decreased since 1950 and across Canada the annual maximum snow depth has also decreased. Overall, studies focusing on the Prairie Provinces in Canada have shown accelerated changes in several climate parameters over time, affecting cropping areas and crop yields.
Micro-PIXE and micro-IBIL characterization of lapis lazuli samples from Myanmar mines and implications for provenance study
Authors: Guidorzi Laura , Re Alessandro , Magalini Marta , Angelici Debora , Borghi Alessandro , Vaggelli Gloria , Fantino Fulvio , Rigato Valentino , La Torre Leonardo , Lemasson Quentin , Pacheco Claire , Pichon Laurent , Moignard Brice , Lo Giudice Alessandro
Published: February 2023

The provenance of raw lapis lazuli used since the Neolithic Age for the realization of carved artefacts can be pivoting for the reconstruction of ancient trade routes. The role of main provider of this material in ancient times is generally attributed to the Badakhshan quarries (Afghanistan), although other deposits could have been exploited as well since antiquity. The systematic multi-technique analysis of lapis lazuli rocks coming from four known source areas (located in present-day Afghanistan, Tajikistan, Siberia and Chile) has led in the last years to the compilation of a protocol for provenance determination. The protocol is based on differences in the physical–chemical properties measured with non-invasive techniques (Ion Beam Analysis (IBA)), making it suitable also for precious ancient artefacts. In this work, 10 new reference samples from the Mogok quarry (Myanmar), previously subjected to a complete petrographic and mineralogical characterization, have been analysed employing $$\mu$$
μ
-PIXE (Proton Induced X-ray Emission) and $$\mu$$
μ
-IBIL (Ion Beam Induced Luminescence) techniques. The subdivision of Myanmar samples into three groups, previously suggested, is corroborated by diopside trace elements concentrations. The results also allow to include Myanmar as a new provenance in the analytical protocol, indicating that provenance markers such as presence/absence of wollastonite, altered pyrites and Sr content are still valid to discriminate also the Myanmar lapis lazuli from Chilean or Siberian ones. New weaker markers (Zn content in diopside, Se and Cu contents in pyrite) are proposed for the discrimination of Myanmar from Afghan or Tajik provenances; however, from the analysis it arose the need of investigating new mineral phases with IBA to find strong markers for a definitive discrimination with samples from Southwest Asia.
Improved Neurophysiological Process Imaging Through Optimization of Kalman Filter Initial Conditions
Authors: Zhao Yun , Luong Felix , Teshuva Simon , Pelentritou Andria , Woods William , Liley David , Schmidt Daniel F. , Boley Mario , Kuhlmann Levin
Published: February 2023

Recent work presented a framework for space-time-resolved neurophysiological process imaging that augments existing electromagnetic source imaging techniques. In particular, a nonlinear Analytic Kalman filter (AKF) has been developed to efficiently infer the states and parameters of neural mass models believed to underlie the generation of electromagnetic source currents. Unfortunately, as the initialization determines the performance of the Kalman filter, and the ground truth is typically unavailable for initialization, this framework might produce suboptimal results unless significant effort is spent on tuning the initialization. Notably, the relation between the initialization and overall filter performance is only given implicitly and is expensive to evaluate; implying that conventional optimization techniques, e.g. gradient or sampling based, are inapplicable. To address this problem, a novel efficient framework based on blackbox optimization has been developed to find the optimal initialization by reducing the signal prediction error. Multiple state-of-the-art optimization methods were compared and distinctively, Gaussian process optimization decreased the objective function by 82.1% and parameter estimation error by 62.5% on average with the simulation data compared to no optimization applied. The framework took only 1.6[Formula: see text]h and reduced the objective function by an average of 13.2% on 3.75[Formula: see text]min 4714-source channel magnetoencephalography data. This yields an improved method of neurophysiological process imaging that can be used to uncover complex underpinnings of brain dynamics.
Bose–Einstein condensation theory for any integer spin: Approach based in noncommutative quantum mechanics
Authors: Gamboa J. , Méndez F. , López-Sarrión Justo
Published: February 2023

A Bose–Einstein condensation theory for any integer spin using noncommutative quantum mechanics methods is considered. The effective potential is derived as a multipolar expansion in the non-commutativity parameter [Formula: see text] and, at second order in [Formula: see text], our procedure yields to the standard dipole–dipole interaction with [Formula: see text] playing the role of the strength interaction parameter. The generalized Gross–Pitaevskii equation containing nonlocal dipolar contributions is found. For [Formula: see text] isotopes [Formula: see text] becomes [Formula: see text][Formula: see text][Formula: see text] and, thus for this value of [Formula: see text] one cannot distinguish interactions coming from non-commutativity or those of dynamical origin.
On the discrete version of the Kerr–Newman solution
Authors: Khatsymovsky V. M.
Published: February 2023

This paper continues our work on black holes in the framework of the Regge calculus, where the discrete version (with a certain edge length scale [Formula: see text] proportional to the Planck scale) of the classical solution emerges as an optimal starting point for the perturbative expansion after functional integration over the connection, with the singularity resolved. An interest in the present discrete Kerr–Newman-type solution (with the parameter [Formula: see text]) may be to check the classical prediction that the electromagnetic contribution to the metric and curvature on the singularity ring is (infinitely) greater than the contribution of the [Formula: see text]-function-like mass distribution, no matter how small the electric charge is. Here, we encounter a kind of a discrete diagram technique, but with three-dimensional (static) diagrams and with only a few diagrams, although with modified (extended to complex coordinates) propagators. The metric (curvature) in the vicinity of the former singularity ring is considered. The electromagnetic contribution does indeed have a relative factor that is infinite at [Formula: see text], but, taking into account some existing estimates of the upper bound on the electric charge of known substances, it is not so large for habitual bodies and can only be significant for practically nonrotating black holes.
Mixed convection flow of lower convected second grade with unsteady MHD nanofluid over a stretching surface in porous medium
Authors: Tahir Shauket Ali , Rafaqat Muhammad , Hussan Muhammad , Azam Muhammad
Published: February 2023

This paper presented an analysis for time-varying nanofluid thin liquid layer applied over a stretched heated plate with adjustable concentration and temperature. The governing partial differential equations of problem have been reduced to similar ordinary differential equations through similarity transformation using group theoretic method those are convenient to find solutions along with numerical solution. Analysis comprises for impact of various parameters as Prandtl number Pr, Schmidt number Sc, Thermal exponent r, Concentration exponent s, Deformation rate [Formula: see text], Thermophoresis parameter [Formula: see text], & Brownian motion parameter [Formula: see text], on auxiliary variables like Velocity [Formula: see text], Temperature [Formula: see text] and Concentration [Formula: see text]. The MATHEMATICA software is used to solve and extract graphs for problem. The results have been depicted via graphs to grasp conclusive declaration.
Impact of Arrhenius activation energy on MHD nanofluid flow past a stretching sheet with exponential heat source: A modified Buongiorno’s model approach
Authors: Sharma Pawan K. , Sharma Bhupendra K. , Mishra Nidhish K. , Rajesh Harshini
Published: February 2023

Nanofluids have a wide range of applications in biological research. They are employed in targeted medication administration, hyperthermia (for cancer treatment) and differential diagnostics like magnetic resonance image (MRI). In light of these medical applications, the impact of an external magnetic field and an exponential heat source on the dynamics of [Formula: see text]–[Formula: see text] over a nonlinearly stretched surface has been investigated. A realistic modified Buongiorno model has been used which includes the effects of reaction rate, Biot number and activation energy. The boundary value problem governing the model is solved on MATLAB R2022a using the solver, BVP5C. Further, the consequences of different parameters on rate of heat transfer coefficient (Nusselt number), rate of mass transfer coefficient (Sherwood number), drag coefficient, velocity, temperature and volume fraction profile are observed graphically. It is noted that volume fraction and uniform heat source intensity have a positive effect on the Nusselt number and negative effect on Sherwood number. The effects of thermal radiation and magnetic field on volume fraction profile are, respectively, positive and negative. The current physics of flow across a vertical stretching surface is expected to serve as the foundation for various medical science, engineering and technology applications.
A Big Data-Driven Risk Assessment Method Using Machine Learning for Supply Chains in Airport Economic Promotion Areas
Authors: Ma Zhijun , Yang Xiaobei , Miao Ruili
Published: February 2023

With the rapid development of economic globalization, population, capital and information are rapidly flowing and clustering between regions. As the most important transportation mode in the high-speed transportation systems, airports are playing an increasingly important role in promoting regional economic development, yielding a number of airport economic promotion areas. To boost effective development management of these areas, accurate risk assessment through data analysis is quite important. Thus in this paper, the idea of ensemble learning is utilized to propose a big data-driven assessment model for supply chains in airport economic promotion areas. In particular, we combine two aspects of data from different sources: (1) national economic statistics and enterprise registration data from the Bureau of Industry and Commerce; (2) data from the Civil Aviation Administration of China and other multi-source data. On this basis, an integrated ensemble learning method is constructed to quantitatively analyze the supply chain security characteristics in domestic airport economic area, providing important support for the security of supply chains in airport economic area. Finally, some experiments are conducted on synthetic data to evaluate the method investigated in this paper, which has proved its efficiency and practice.
An Efficient Model for Mitigating Power Transmission Congestion Using Novel Rescheduling Approach
Authors: Mishra Swakantik , Samal Sudhansu Kumar
Published: February 2023

In the electricity business, power evacuation from source to load is a challenging task when there is contingency and agencies have to swirl around for solutions in terms of rescheduling generator dispatch, load slashing, adding of network, etc. The more challenging scenario arises when the independent operator wants to re-dispatch a generator during the contingent situation. So, in this paper, we focus on a new generator rescheduling technique with congestion price and transmission security as an intervention. The significant intention of this paper involves restricting the load thereby dispatching a particular generator or a set of generators with low cost and secure transmission line. In addition to this, the network jamming is unpredictable and does not follow any pattern, but power supply in some zones is disrupted due to hidden reasons. Therefore, a macroscopic or holistic approach is adopted for congestion forecasting through demand schedule, gathering, minimum as well as maximum drawls. Here, two significant factors namely the transmission utilization charges as well as transmission congestion charges for predicting the congestion of a transmission line are evaluated. Finally, the experimental analysis to determine transmission utilization charges, transmission congestion charges, cost function and generation supply as well as demand balance with congestion optimization.
Intelligent Edge Based Efficient Disease Diagnosis Using Optimization Based Deep Maxout Network
Authors: Ancy Breen W , Muthu Vijaya Pandian S
Published: February 2023

The healthcare model is considered an imperative part of remote sensing of health. Finding the disease requires constant monitoring of patients’ health and the detection of diseases. In order to diagnose the disease utilizing an edge computing platform, this study develops a method called grey wolf invasive weed optimization-deep maxout network (GWIWO-DMN). The proposed GWIWO, which is developed by integrating invasive weed optimization (IWO) and grey wolf optimization (GWO), is used here to train the DMN. The distributed edge computing platform consists of four units, namely monitoring devices, first layer edge server, second layer edge server, and cloud server. The monitoring devices are used for accumulating patient information. The preprocessing and feature selection are performed in the first layer edge server. Here, the preprocessing is carried out using the exponential kernel function. The selection of features is done using Jaro–Winkler distance in the first layer edge server. Then, at the second layer edge server, clustering and classification are carried out using deep fuzzy clustering and DMN, respectively. The proposed GWIWO algorithm is used to do the DMN training. Finally, the cloud server processes the decision fusion. The proposed GWIWO-DMN outperformed with the highest true positive rate (TPR) of 89.2%, highest true negative rate (TNR) of 93.7%, and highest accuracy of 90.9%.
On the Succinctness of Modal μ-Calculus Based on Covariant–Contravariant Refinement
Authors: Xing Huili
Published: February 2023

The expressive power of logics is one of the major research topics in mathematical logic and computer science. One way of comparing the complexities of different formalisms (e.g. knowledge representation formalisms) stems from the perspective of representational succinctness. The concept of covariant–contravariant refinement (CC-refinement, for short) generalizes the concepts of refinement, simulation and bisimulation. We introduce an extension of the standard multi-agent modal [Formula: see text]-calculus system [Formula: see text] with CC-refinement operators ([Formula: see text]) and show that [Formula: see text] is equivalently expressive to [Formula: see text]. This paper presents the succinctness results of [Formula: see text] compared with [Formula: see text] from two viewpoints based on the sets of covariant and contravariant actions. We establish a family of CC-refinement formulas for comparing the succinctness based on the well-known parity symmetric alternating automata, which is often used to describe modal [Formula: see text]-calculus formulas.
Strongly quasiconvex subgroups in amalgams and HNN extension
Authors: Nguyen Hoang Thanh , Tran Hung Cong
Published: February 2023

In this paper, we give a condition under which strong quasiconvexity in a finitely generated group is preserved under amalgams and HNN extension.
An Explainable AI Model for ICU Admission Prediction of COVID-19 Patients
Authors: Dazea Eleni , Stefaneas Petros
Published: February 2023

COVID-19 has overwhelmed hospitals all around the world, because of the very high number of patients requiring intubation. Predicting and anticipating which patients will be intubated can help hospitals better allocate their resources. For this, we created an explainable AI model that receives some medical data for each patient and returns a prediction on whether they will be intubated later on, while also explaining the argumentation process that led to that conclusion. This model can help medical professionals better manage the ICU beds and the patients between hospitals and warn them on the symptoms and signs to look for in patients worsening. To obtain the model, we first trained various ML algorithms on a dataset of COVID ICU admissions. Then, using the most accurate of the models, we obtained the sum of the most important rules, using R’s inTrees framework. With the rules obtained, we produced a program in Gorgias written in Prolog. We added some more rules and changed the ordering to come up with a program that requires some patient vitals and blood results as inputs and then returns the prediction along with its reasoning.
Observable features of tachyon-dominated cosmology
Authors: Martin Audrey Claire , Redmount Ian H.
Published: February 2023

A Friedmann–Robertson–Walker cosmological model dominated by tachyonic — faster-than-light — dark matter can exhibit features similar to those of a standard dark energy/dark matter or [Formula: see text]CDM model. It can undergo expansion which decelerates to a minimum rate, passes through a “cosmic jerk,” then accelerates. But some features of a tachyon-dominated model are sufficiently distinct from those of the Standard Model that the two possibilities might be distinguished observationally. As a demonstration of concept, the distance-redshift relation of such a model is compared here with some observations of Type Ia supernovae. Other measures of the third time derivative of the cosmic scale factor — the true cosmic jerk — might be found to test a tachyonic-dark-matter hypothesis.
Orbital precession and other properties of two-body motion in the presence of dark energy
Authors: Bisnovatyi-Kogan G. S. , Merafina M.
Published: February 2023

We consider the Kepler two-body problem in the presence of a cosmological constant [Formula: see text]. Several dimensionless parameters characterizing the possible orbit typologies are used to identify open and closed trajectories. The qualitative picture of the two-body motion is described and critical parameters of the problem are found.
INFLUENCES OF P AND Sr ON MICROSTRUCTURE AND ITS EFFECTS ON MACHINABILITY AND MECHANICAL PROPERTIES OF HYPEREUTECTIC Al-20%Si
Authors: ARUNKUMAR D. T. , BASAVAKUMAR K. G. , SUJAI S. , PRABU S. SENTHUR
Published: February 2023

Hypereutectic Al-Si alloys are widely utilized in the automotive industry due to their high strength-to-weight ratio, minimal thermal expansion, and superior castability. The downside of hypereutectic Al-Si alloys is the formation of coarse primary silicon particles. The primary Si phases were controlled by the growth-hindering agents, phosphorus (refiner), and strontium (modifier) by using a conventional stir casting technique at room temperature. The microstructural changes were observed through an optical microscope and SEM analysis. The additions of 0.08% P have ensured the formation of the uniformly distributed fine-grained particles in the alloy. The primary silicon particle size was reduced from 220[Formula: see text][Formula: see text]m to 150[Formula: see text][Formula: see text]m as compared to the untreated alloy. The tensile and yield properties of the treated alloy were increased by 12.7% when compared to the untreated alloy with a hardness of 131 BHN. The treated alloy imparted better impact toughness, ensuring a ductile mode of failure through the fractography studies. The influence of the microstructure on the machinability of the alloy was investigated in a dry environment with uncoated and coated inserts (code: CCGT 09T304 FL K10) by varying the process parameters, i.e. speed, feed rate, and depth of cut (DoC). Modification of the primary and eutectic Si phases of an Al-20Si hypereutectic alloy increases machinability with coated inserts as well as its mechanical properties.
EFFECT OF CASE DEPTHS ON CORROSION PROPERTIES OF HARD ANODIC OXIDIZED A356 ALUMINUM ALLOY
Authors: HACIOSMANOĞLU MURAT , BAŞYİĞİT AZİZ BARIŞ , HEKİMOĞLU ALİ PAŞA , BİCAN OSMAN
Published: February 2023

In this work, A356 alloy samples having a dimension of [Formula: see text][Formula: see text]mm were coated by hard anodic oxidation method at eight different thicknesses up to [Formula: see text]80[Formula: see text][Formula: see text]m. The sample surfaces and longitudinal section of these surfaces in both coated and uncoated conditions were investigated with a scanning electron microscope (SEM). Microhardness of the coating layers and core regions (base metal) were determined with the microvickers hardness testing method. Corrosion properties of the coated and uncoated samples were investigated by an electrochemical corrosion test set up according to ASTM G5 standard. The test results obtained from the coated and uncoated surfaces were compared to each other. Coated surfaces exhibited fluctuant surface profile. Microcracks were formed on these surfaces. Microhardness of the coating layers increased with increasing coating layer thickness. Energy dispersed X-ray spectroscopy (EDS) analysis of the surfaces showed that oxygen rate on the surfaces increased after the corrosion tests. Corrosion rate of the A356 alloy coated by hard anodic oxidation decreased with increasing coating thickness up to 40–50[Formula: see text][Formula: see text]m, but after this coating thickness, the corrosion rate increased. The results obtained from the investigations were discussed based on the characteristics of the coated surfaces.
EXPERIMENTAL EVALUATION OF PARAMETERS AFFECTING DELAMINATION FACTOR, TENSILE STRENGTH, THRUST FORCE AND SURFACE ROUGHNESS IN DRILLING OF GFRP
Authors: KILICKAP EROL , ÇELIK YAHYA HIŞMAN , YENIGUN BURAK
Published: February 2023

The drilling of glass fiber-reinforced plastic (GFRP) composites gained importance since they are used as structural components in many industries such as automotive, aerospace, and aviation. A large number of holes are needed in the industry to join these composite parts. However, some failures occur in drilling GFRP composites, such as delamination, matrix cracking, and fiber breakage. These failures not only reduce the strength of the composite, but also reduce its service life. Drilling parameters, drill bits, and woven types have a great influence on the occurrence of these failures by greatly influencing the thrust force, surface quality, and cutting temperature. In this study, the effects of drilling parameters and woven types of GFRP composites on thrust force, surface roughness, delamination factor, and cutting temperature were examined in the drilling of uni-directional (UD), [Formula: see text] and 0[Formula: see text] GFRP woven composites. The effects of drilling parameters and the delamination factor on the tensile strength of the drilled specimen were also investigated. The result of this study indicated that thrust force, delamination factor, and surface roughness increased with increasing cutting speed and feed rate. An increase in feed rate decreased the cutting temperature, while an increase in cutting speed increased the cutting temperature. Also, it was found that the delamination factor had a critical influence on the tensile strength of the GFRP composites.
CHARACTERIZATION AND PERFORMANCE IMPROVEMENT OF SiC-REINFORCED Cu-MATRIX-BASED COMPOSITES AS ELECTRODE FOR EDM MACHINING
Authors: SOMANI NALIN , TYAGI Y. K. , GUPTA NITIN KUMAR , DAS ANSHUMAN
Published: February 2023

Pure copper, copper-based alloys, brass, graphite and steel are the most common tool materials for the electrical discharge machining (EDM) process. The electrode material, which exhibits good conductivity to heat and electricity and possesses better mechanical and thermal properties, is preferred for EDM applications. The major problem with conventional electrodes like copper and graphite is their low wear resistance capacity. This study is on the fabrication of Cu–SiC composites as an electrode of EDM with improved wear characteristics for machining of hardened D2 steel which is widely used in die formation. Powder metallurgy route was used to fabricate the samples which was further followed by three-step sintering process. Copper metal was used as a matrix element which was reinforced with SiC in volume fractions of 10%, 15% and 20%. Based on the desirable properties for the EDM tool, the best composition of Cu–SiC composite tool tip was suggested and was further used for machining of D2 steel. The performance of newly developed Cu–SiC composite electrode in terms of surface roughness (SR), material removal rate (MRR) and tool wear rate (TWR) was explored, and it was compared with the pure copper electrode. Pulse on-time, pulse off-time and the input current were selected as the input process parameters. Result reveals that the TWR and SR were decreased by 12–18% and 10–12%, whereas the MRR was increased by 9–28% for Cu–SiC composite tool as compared to the pure Cu electrode. Adequacy of the results was checked by statistical analysis. The surface texture of tool and machined surface was analyzed using scanning electron microscopy (SEM). SEM micrograph revealed that surface cracks on composite tool tip were lesser than pure Cu tool tip, whereas the work surface was rough while machining with the copper tool surface. Therefore, the result indicates that the newly developed Cu–SiC composite tool can be used for machining of hard materials with EDM.
Vibration Analysis and Diagnostics of a High Speed Centrifuge for Fast Reactor Fuel Reprocessing Applications
Authors: Velaga Satish K. , Saurav  , Ashwin M. , Kumar P. Anup , Ravi P. , Kumar S. Suresh , Karthi A. K. , Kumar M. Dhananjeya , Sreedhar B. K. , Ananthasivan K.
Published: February 2023

This study aims at understanding the cause of vibrations observed during the operation of high speed centrifuges in a radioactive environment and materializing ways to mitigate these vibrations to ensure dynamic stability of centrifuges during operation. For this, a condition-based monitoring study was carried out for the centrifuge and its supporting structure using dynamic co-relation study in frequency domain during the operation of centrifuge at its operating speed of 19[Formula: see text]700[Formula: see text]rpm. Dynamic characteristics of the support structure were analyzed using standard finite element code. It was observed that high vibration amplitudes in the original support structure, before modification, owed to its low structural stiffness. Hence, structural modifications were carried out to reduce the dynamic crossover response of the support structure at the critical speeds and operating speeds of centrifuge. It was found that structural modification resulted in considerable reduction in the vibration amplitude of the support structure, compared to its initial configuration.
A Joint Model for Target-Oriented Opinion Words Extraction and Sentiment Classification
Authors: Dai Chenyang , Shen Bo , Yan Fengxiao
Published: February 2023

Target-oriented opinion word extraction and aspect-level sentiment classification are two highly relevant tasks in aspect-based sentiment analysis. Previous studies tend to separate them and focus on one of the tasks, which ignore the connection between opinion word extraction and sentiment classification, and result in the waste of useful connection information. In this paper, we propose a co-extraction model, in which the two tasks are formulated as a sequence labeling problem. The model involves two stacked Bi-LSTM modules and an information interaction component to generate all opinion-polarity pairs of the input sentences simultaneously. The experimental results show that our model achieves advanced results in target opinion word-polarity co-extraction. The performance of both tasks is stronger than the baseline, and the model is of low complexity and high operational efficiency.
Finite Element Analysis Combined With Machine Learning to Simulate Open-Hole Strength and Impact Tests of Fibre-Reinforced Composites
Authors: Reiner Johannes
Published: February 2023

Data-driven calibration techniques, consisting of theory-guided feed-forward neural networks with long short-term memory, have previously been developed to find suitable input parameters for the finite element simulation of progressive damage in fibre-reinforced composites subjected to compact tension and compact compression tests. The results of these machine learning-assisted calibration approaches are assessed in a range of virtual open-hole strength tests under tensile and compressive loadings as well as in low velocity impact tests. It is demonstrated that the calibrated material models with bi-linear softening are able to simulate the structural response qualitatively and quantitatively with a maximum error of 9[Formula: see text] with regards to experimentally measured open-hole strength values. Furthermore, the highly efficient models enable the virtual analysis of size effects as well as accurate force simulations in quasi-isotropic laminates under impact loading.
Mental Health and Homelessness
Authors: Mordeson John N. , Mathew Sunil , Sujithra P
Published: February 2023

Homeless people have a prevalence of mental illness when compared to the general population. They are more likely to suffer from alcoholism and drug dependency. Being chronically homeless also means that people with mental illness are more likely to experience catastrophic health crises requiring medical intervention or resulting in institutionalization within the criminal justice system. In this paper, we consider the rankings of states with respect to homelessness and mental health. We use fuzzy similarity measures to determine the degree of similarity between these rankings. We determine measures of similarity of these rankings using techniques of fuzzy similarity relations.