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The plasma-wall transition is investigated by a one-dimensional steady-state multifluid model, which was presented in detail in Part I [T. Gyergyek et al., AIP Adv. 14, 045201 (2024)]. In this work, the plasma-wall transition is analyzed for the case where the plasma consists of singly charged positive ions, electrons, and singly charged negative ions. When the temperature and initial density of the negative ions are varied, a transition between two types of solutions of the model is observed. We call them the low and high solution, with respect to the absolute value of the potential drop. When the density and temperature of the negative ions are above a critical value, the low solution is observed. As the mass of the positive ions increases, these critical values also increase, but only until the ion mass is below about 1000 electron masses. With larger ion masses, the critical density of the negative ions and the temperature no longer change. In the low solution, the potential drop in front of the sheath is determined by the negative ions and is smaller in absolute terms than in the case of the high solution, where the potential drop in front of the sheath is determined by the electrons. If the problem is analyzed on the pre-sheath scale, the transition between the low and high solution is very sharp. However, when the neutrality condition is replaced by the Poisson equation, this transition becomes blurred and the solutions of the model equations exhibit oscillations. The role of the smallness parameter is highlighted. It is shown how the initial electric field is determined. Deviation of the negative ion density profile from the Boltzmann relation is discussed. [ABSTRACT FROM AUTHOR]

In this work, we determine the dissociation line of the nitrogen (N2) hydrate by computer simulation using the TIP4P/Ice model for water and the TraPPE force field for N2. We use the solubility method proposed recently by some of us to evaluate the dissociation temperature of the hydrate at different pressures, from 500 to 1500 bar. Particularly, we calculate the solubility of N2 in the aqueous solution when it is in contact with a N2-rich liquid phase and when in contact with the hydrate phase via planar interfaces as functions of temperature. Since the solubility of N2 decreases with temperature in the first case and increases with temperature in the second case, both curves intersect at a certain temperature that determines the dissociation temperature at a given pressure. We find a good agreement between the predictions obtained in this work and the experimental data taken from the literature in the range of pressures considered in this work. From our knowledge of the solubility curves of N2 in the aqueous solution, we also determine the driving force for nucleation of the hydrate, as a function of temperature, at different pressures. In particular, we use two different thermodynamic routes to evaluate the change in chemical potential for hydrate formation. Although the driving force for nucleation slightly decreases (in absolute value) when the pressure is increased, our results indicate that the effect of pressure can be considered negligible in the range of pressures studied in this work. To the best of our knowledge, this is the first time the driving force for nucleation of a hydrate that exhibits crystallographic structure sII, along its dissociation line, is studied from computer simulation. [ABSTRACT FROM AUTHOR]

At present, optical anapole resonances in nanostructures have attracted increasing attention due to the strong field confinement and substantially suppressed scattering. This study provides the results of three-dimensional finite-difference time-domain simulations exhibiting the possibility of the anapole state in high refractive index dielectric nanohole array metasurfaces having different profiles of the holes (square, hexagon, and octagon). Behavior of the effective optical Kerr nonlinearity of the metasurfaces in the vicinity of the anapole state is investigated. Depending on the geometry, the absolute value of the effective nonlinear Kerr coefficient of the metasurface may be up to three orders of magnitude greater than that of the unstructured film. A square transverse section of the nanohole is preferable for the optical Kerr effect in the holey metasurfaces. The effect of the random rotation of the square holes representing the metasurface irregularity on the optical nonlinearity is examined. As a result, the dielectric nanohole array metasurfaces display a concrete possibility to have the anapole state with large enhancement of the optical nonlinearity. [ABSTRACT FROM AUTHOR]

This paper presents an advanced measurement method for controlling the surface charge carrier density of passivated silicon wafers during photoconductance and photoluminescence measurements, by employing semitransparent poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) electrodes with an applied bias voltage. This is employed to study and analyze charge carrier dynamics in dielectric layers by measuring their direct influence on effective lifetime. With this method, the carrier population at the surface and the effective carrier lifetimes of n- and p-type samples can be investigated, from which the fixed charge carrier density Qf of the passivation can be extracted. Additionally, the defect density Dit can also be derived from the minimum lifetime values at flatband voltage. In SiO2/Al2O3 stacks with varying SiO2 interlayer thickness, it was shown that by changing the SiO2 thickness, the carrier density Qf can be tuned to a wide range of values, which corresponds to the results obtained in other studies. An increase in interlayer thickness resulted in a decrease in Qf. Varying the SiO2 thickness, the behavior of the respective effective lifetime under bias voltage also changes, exhibiting hysteresis-like effects, which are attributed to additional charges getting trapped at the surface during bias-voltage application. This effect is much more pronounced for samples with a thinner SiO2 layer as well as for the n-type samples. Additionally, the doping type also influences the magnitude of Qf, with p-type samples generally reaching lower absolute values. It was also shown that aging of the samples had a significant effect on the measured Qf, which was increased compared to the initial Qf of the passivation. This effect was more pronounced for the n-type samples. The measurements were realized by a cost-effective and easy-to-use microcontroller-based potentiostat, which can be used as a simple add-on to existing photoconductance or photoluminescence measurement setups. [ABSTRACT FROM AUTHOR]

The computation of entropy in liquids and liquid crystal (LC) phases is a big challenge in statistical physics. In this work, we extend the two-phase thermodynamic model (2PT) to shape anisotropic soft repulsive spherocylinders (SRSs) and report the absolute values of entropy for different LC phases for a range of aspect ratios L/D = 2 − 5. We calculate the density of states for different LC phases and decompose it into contributions arising from translational and rotational degrees of freedom. The translational and rotational modes are further partitioned into diffusive, gas-like, and non-diffusive, solid-like components using a fluidicity factor. In the dilute limit, the entropy values obtained from the 2PT method match exactly those of an ideal rigid rotor. We find that, for a given packing fraction, the magnitude of the total entropy is roughly equal regardless of the different LC phases associated with different aspect ratios. We also compute the excess entropy (for L/D = 5) and compare those with the values obtained using the standard integration approach of MD or Monte Carlo equation of state of SRS. The values obtained using both approaches match very well. The rotational and translational fluidicity factors are further used to determine the phase boundaries of different LC phases. [ABSTRACT FROM AUTHOR]

We report a theoretical modeling of the flexoelectric response of dielectric–ferroelectric (DE–FE) multilayers based on phase field simulations in the framework of the Landau–Ginzburg–Devonshire (LGD) theory. The correlation between negative capacitance and flexoelectric response is revealed, and the single-domain and multi-domain models are compared. It shows that the dielectric layers drive the ferroelectric layer into a negative capacitance regime, and the flexoelectric response of the multilayer is maximal when the negative capacitance of the ferroelectric layer has a minimal absolute value. Moreover, the flexoelectric response peak will be shifted to a lower temperature by increasing the thickness of dielectric layer, indicating a possibility of achieving a stronger flexoelectric response at room temperature compared with that of pure ferroelectric. However, while the single-domain model shows that the flexoelectric response peak is simply shifted to a lower temperature with near constant peak value and width, the multi-domain model reveals a significant suppressing of the flexoelectric peak by the dielectric layer. This is attributed to the formation of the vortex domain state, which eases the depolarization effect and leads to large absolute value of negative capacitance of the ferroelectric layer. Our work provides new insights into flexoelectricity in ferroelectric heterostructures. [ABSTRACT FROM AUTHOR]

The aim of this paper was to investigate intumescent coatings based on polyfurfuryl alcohol (PFA) resin as a binder benefiting from high char yield and low smoke emission. To this end, the coatings composition in terms of PFA binder resin, long oil alkyd plasticizing resin, TiO2 pigment, and flame-retardant additives (FR) was changed as input parameters according to a mixture design-of-experiments. The corresponding changes in the backside temperature of mild steel substrate (Tb), residual char expansion ratio, limiting oxygen index, and char residue (wt% @1000 °C) were studied as the response variables describing fire performance characteristics of the coatings. The results showed that the backside temperature of the plate increased and the expansion ratio decreased with increasing in the alkyd resin concentration. Also, the flame-retardant efficiency of coatings strongly depends on the content of FR additives. When the content of PFA and alkyd resin was increased at a high level (35 and 4 wt%, respectively), the Tb of the coated plates reached 415 °C rapidly, due to the cracking of the coating and the lower concentration of FR additives. However, the formula with higher FR content, i.e., 68 wt%, showed the lowest Tb value ca. 128 °C. Flame-retardant characteristics directly depended on the expansion ratio of the coatings and the morphology of the char layer remaining on the substrate after the flame test; therefore, coatings with a higher expansion ratio showed lower backside temperature. The findings were supported by examining of the remaining char morphology after a flame test by optical microscopy and validated by comparing the predicted and actual responses for optimization. The value of absolute relative deviation was obtained in the range of 1.6–7.9, which indicates a good agreement between the proposed and experimental results. [ABSTRACT FROM AUTHOR]

Deligne proved in [Extensions centrales non résiduellement finies de groupes arithmetiques, C. R. Acad. Sci. Paris 287 (1978) 203–208] (see also 7.1 in [R. Hill, Fractional weights and non-congruence subgroups, in Automorphic Forms and Representations of Algebraic Groups Over Local Fields, eds. H. Saito and T. Takahashi, Surikenkoukyuroku Series, Vol. 1338 (2003), pp. 71–80]) that the weights of Siegel modular forms on any congruence subgroup of the Siegel modular group of genus g > 1 must be integral or half integral. Actually he proved that for a system v (M) of complex numbers of absolute value 1 v (M) det (C Z + D) r (r ∈ ℝ) (0. 1) can be an automorphy factor only if 2 r is integral. We give a different proof for this. It uses Mennicke's result [Zur Theorie der Siegelschen Modulgruppe, Math. Ann. 159 (1965) 115–129] that subgroups of finite index of the Siegel modular group are congruence subgroups and some techniques from [Solution of the congruence subgroup problem for SL n (n ≥ 3) and Sp 2 n (n ≥ 2) , Publ. Math. Inst. Hautes Études Sci. 33 (1967) 59–137] of Bass–Milnor–Serre. [ABSTRACT FROM AUTHOR]

The SOR-like iteration method for solving the system of absolute value equations of finding a vector x such that A x - | x | - b = 0 with ν = ‖ A - 1 ‖ 2 < 1 is investigated. The convergence conditions of the SOR-like iteration method proposed by Ke and Ma (Appl. Math. Comput., 311:195–202, 2017) are revisited and a new proof is given, which exhibits some insights in determining the convergent region and the optimal iteration parameter. Along this line, the optimal parameter which minimizes ‖ T ν (ω) ‖ 2 with T ν (ω) = | 1 - ω | ω 2 ν | 1 - ω | | 1 - ω | + ω 2 ν and the approximate optimal parameter which minimizes an upper bound of ‖ T ν (ω) ‖ 2 are explored. The optimal and approximate optimal parameters are iteration-independent, and the bigger value of ν is, the smaller convergent region of the iteration parameter ω is. Numerical results are presented to demonstrate that the SOR-like iteration method with the optimal parameter is superior to that with the approximate optimal parameter proposed by Guo et al. (Appl. Math. Lett., 97:107–113, 2019). [ABSTRACT FROM AUTHOR]

In this paper, we focus on solving the generalized absolute value equations (GAVE). We present a new method named as modulus-based block triangular splitting iteration (MBTS) method based on the block matrix structure resulting from the transformation of the GAVE into two equations. This method is developed by decomposing the matrix into diagonal and triangular matrices, as well as applying a series of suitable combination and modification techniques. The advantage of the MBTS method is that it is not necessary to solve the inverse of the coefficient matrix of the linear equation system during each iteration, which greatly improves the computational speed and reduces its storage requirements. In addition, we present some convergent theorems proving by different techniques and the estimate of the required number of iteration steps. Furthermore, in the accompanying corollaries, we provide some estimations for choosing appropriate parameter values. Finally, we validated the effectiveness and efficiency of our newly developed method through two numerical examples of the GAVE. [ABSTRACT FROM AUTHOR]

Three‐dimensional hydrodynamic numerical simulation and laboratory fish‐passage experiment with juvenile grass carp (Ctenopharyngodon idella) were used to systematically estimate hydrodynamic parameters, fish passage efficiency, fish swimming behavior, and fish swimming trajectories in a vertical‐slot fishway (VSF) under five different flow discharges. The spatial‐mean time‐averaged velocity magnitude along the slot section determined passage success rate. The absolute value of the time‐averaged Reynolds‐shear‐stress component in the X–Y direction played a decisive role in selecting the swimming path. In addition, fish energy expenditure along the mean‐50% swimming route indicated that higher mainstream velocity did not necessarily signify larger energy consumption, because successfully‐migrating fish selected the relatively lower velocity zone during the migration process. Our findings for fish swimming behavior in response to velocity and turbulence can be used to develop high‐efficiency fishways for grass carps or other species with similar traits. [ABSTRACT FROM AUTHOR]

The objective of this study is to explore the patterns of alteration in left ventricular systolic function among patients with severe aortic stenosis (SAS) through the application of automatic myocardial motion quantification (aCMQ) techniques. Furthermore, we seek to ascertain dependable quantitative markers for the assessment of impaired left ventricular function in patients with SAS and an ejection fraction (EF) ≥ 60%. Seventy patients who underwent echocardiography and received a diagnosis of severe aortic stenosis (SAS) in the hospital from November 2021 to August 2022 were selected for the SAS group and categorized into three subgroups based on ejection fraction (EF)—SAS group with EF ≥ 60%, SAS group with EF ranging from 50% to 59%, and SAS group with EF < 50%. Concurrently, 30 healthy individuals were recruited at the hospital during the same timeframe to serve as the control group. Participants from both groups underwent standard transthoracic echocardiography to assess conventional echocardiographic parameters. Dynamic images were examined using automatic myocardial motion quantification (aCMQ) software to derive longitudinal peak strain (LPS) parameters, which were then subjected to statistical analysis. In comparison to the control group participants, the measurements of ascending aorta diameter (AoD), left atrium diameter (LAD), interventricular septal end diastolic thickness (IVSd), left ventricular posterior wall end diastolic thickness (LVPWd), peak systolic velocity (Vmax), and mean pressure gradient (MPG) were significantly higher in the SAS groups (p < 0.05). When compared to participants in the SAS group with an EF ≥ 60%, the values of IVSd, LVPWd, Vmax, and MPG in the SAS group with EF ranging from 50% to 59% were significantly elevated (p < 0.05). Similarly, left ventricular end-diastolic diameter (LVEDD), the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity (E/e'), and the ratio of early to late diastolic mitral inflow velocities (E/A) in the SAS group with EF < 50% were significantly elevated (p < 0.05). The absolute values of longitudinal peak strain (LPS) in the SAS groups were significantly lower in comparison to those in the control group (p < 0.05). Furthermore, all measurements of left ventricular global longitudinal systolic peak strain (GLPS) showed a positive correlation with MPG, a moderate negative correlation with aortic valve area index (AVAI), and a moderate positive correlation with E/A. Patients with SAS and an EF < 50% exhibited the most profound impairment in left ventricular myocardial function. Utilizing the aCMQ technique enables the precise and quantitative evaluation of the severity of impaired left ventricular systolic function in patients within the SAS group with an EF ≥ 60%. [ABSTRACT FROM AUTHOR]

Both experimental and theoretical works have demonstrated that two-dimensional materials exhibit strong thickness-dependent electronic and linear optical properties. However, the nonlinear optical (NLO) effect with respect to the thickness still needs to be further investigated, which is of great significance to design different photonic devices. Herein, we develop the physical vapor deposition technique to prepare a series of antimony selenide (Sb2Se 3) films. The relationship between the thickness of Sb2Se3 film and the NLO absorption was investigated by a Z -scan system under 35 fs, 800 nm laser excitation. The result shows the thicker Sb2Se3 film (∼ 50 nm) performs a larger third-order NLO susceptibility (Im χ (3)) approximately − 4. 5 9 × 1 0 − 8 esu, which can be interpreted by the stronger photon absorption, lower saturable intensity, and larger absorption cross-section of ground-state. More importantly, the Im χ (3) absolute value of thick Sb2Se3 film is also far larger than those of graphene, black phosphorus, transition metal dichalcogenide, MXenes, and heterostructure. This work demonstrates that Sb2Se3 film is an excellent saturable absorber and provides a promising application in nonlinear photonics. [ABSTRACT FROM AUTHOR]

The effects of polymethylene bridges on the chiroptical properties of trans-bis[(β-iminomethyl)naphthoxy]platinum(II) platforms were examined both experimentally and theoretically using newly designed planar chiral Pt analogues (1) having three-dimensional superstructures. A series of optically pure polymethylene-vaulted Pt complexes (R)- and (S)-1 were synthesized and characterized with regard to the chiroptical behaviour of the trans-bis[(β-iminomethyl)naphthoxy]platinum(II) platforms. These complexes were found to exhibit structure-dependent chiroptical characteristics in solution, such that the absolute values of specific rotation, the circular dichroism dissymmetry factor (gabs) and the circularly polarized luminescence dissymmetry factor (glum) all increased upon shortening the polymethylene bridges. Density functional theory and time dependent density functional theory calculations were used to analyse vaulted and non-vaulted complexes, which demonstrated that the present linker-dependent chiroptical properties resulted from constraint-induced changes in the square planar Pt coordination centres rather than from chiral distortion along the coordination platforms. [ABSTRACT FROM AUTHOR]

Drugs like opioids are potent reinforcers thought to co-opt value-based decisions by overshadowing other rewarding outcomes, but how this happens at a neurocomputational level remains elusive. Range adaptation is a canonical process of fine-tuning representations of value based on reward context. Here, we tested whether recent opioid exposure impacts range adaptation in opioid use disorder, potentially explaining why shifting decision making away from drug taking during this vulnerable period is so difficult. Participants who had recently (<90 days) used opioids (n = 34) or who had abstained from opioid use for ≥ 90 days (n = 20) and comparison control participants (n = 44) completed a reinforcement learning task designed to induce robust contextual modulation of value. Two models were used to assess the latent process that participants engaged while making their decisions: 1) a Range model that dynamically tracks context and 2) a standard Absolute model that assumes stationary, objective encoding of value. Control participants and ≥90-days-abstinent participants with opioid use disorder exhibited choice patterns consistent with range-adapted valuation. In contrast, participants with recent opioid use were more prone to learn and encode value on an absolute scale. Computational modeling confirmed the behavior of most control participants and ≥90-days-abstinent participants with opioid use disorder (75%), but a minority in the recent use group (38%), was better fit by the Range model than the Absolute model. Furthermore, the degree to which participants relied on range adaptation correlated with duration of continuous abstinence and subjective craving/withdrawal. Reduced context adaptation to available rewards could explain difficulty deciding about smaller (typically nondrug) rewards in the aftermath of drug exposure. [ABSTRACT FROM AUTHOR]

The spectral radius of a square matrix is the maximum among absolute values of its eigenvalues. Suppose a square matrix is nonnegative; then, by Perron–Frobenius theory, it will be one among its eigenvalues. In this paper, Perron–Frobenius theory for adjacency matrix of graph with self-loops A G S will be explored. Specifically, it discusses the nontrivial existence of Perron–Frobenius eigenvalue and eigenvector pair in the matrix A G S − σ n I , where σ denotes the number of self-loops. Also, Koolen–Moulton type bound for the energy of graph G S is explored. In addition, the existence of a graph with self-loops for every odd energy is proved. [ABSTRACT FROM AUTHOR]

We show that the Nernst-Planck-Euler system, which models ionic electrodiffusion in fluids, has global strong solutions for arbitrarily large data in the two dimensional bounded domains. The assumption on species is either there are two species or the diffusivities and the absolute values of ionic valences are the same if the species are arbitrarily many. In particular, the boundary conditions for the ions are allowed to be inhomogeneous. The proof is based on the energy estimates, integration along the characteristic line and the regularity theory of elliptic and parabolic equations. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to investigate the accuracy of cup position and assess the changes in pelvic tilt during primary total hip arthroplasty (THA) in the lateral decubitus position using a new computed tomography (CT)-based navigation system with augmented reality (AR) technology. Materials and methods: There were 37 cementless THAs performed using a CT-based navigation system with AR technology in the lateral decubitus position and 63 cementless THAs performed using manual implant techniques in the lateral decubitus position in this retrospective study. Postoperative cup radiographic inclination and anteversion were measured using postoperative CT, and the proportion of hips within Lewinnek's safe zone was analyzed and compared between the two groups. The mean absolute values of navigation error were assessed. Intraoperative pelvic tilt angles were also recorded using navigation system. Results: The percentage of cups inside Lewinnek's safe zone was 100% in the navigation group and 35% in the control group (p < 0.001). The mean absolute values of navigation error in inclination and anteversion were 2.9° ± 2.1° and 3.3° ± 2.4°, respectively. The mean abduction angle of the pelvis was 5.1° ± 4.8° after placing the patients in the lateral decubitus position and 4.1° ± 6.0° after cup placement. The mean posterior tilt angle was 6.8° ± 5.1° after placing the patients in the lateral decubitus position and 9.3° ± 5.9° after cup placement. The mean internal rotation angle was 14.8° ± 7.4° after cup placement. There were no correlations between the navigation error in inclination or anteversion and the absolute values of changes of the pelvic tilt angle at any phase. Conclusions: Although progressive pelvic motion occurred in THA in the lateral decubitus position, especially during cup placement, the CT-based navigation system with AR technology improved cup placement accuracy. [ABSTRACT FROM AUTHOR]

Prognostic health management (PHM) is essential for the predictive maintenance of industrial systems, aiming to predict the remaining useful life (RUL) of system to ensure safe, reliable, and cost-effective operation of the machinery. This work proposes an innovative method for RUL prediction of bearings, by combining a health indicator (HI) proposed from the absolute cumulative modified multiscale permutation entropy (C-MMPE) feature with a deep learning long short-term memory (LSTM) model. The work also introduces a virtual health degree for bearings, using an exponential degradation pattern as the target function for the LSTM model output. Experimental validation showcases the effectiveness of proposed approach, achieving a high score value of 0.81 and demonstrating a lower mean absolute error value of 7.38 in RUL prediction for test bearings compared to conventional features and regression labeling functions. This highlights the superior RUL prediction capability of the proposed methodology. [ABSTRACT FROM AUTHOR]

According to archival data for the period from 1923 to 2022, the long-term (interdecadal and interannual) variability of the dissolved oxygen concentration and temperature in the surface layer of the Black Sea in the spring hydrological season (from May to June) is analyzed. The lowest oxygen concentrations over the entire period of instrumental observations (approximately 100 years) were observed on the northwestern shelf and in the open part of the Black Sea for the period from 1923 to 1932. The negative anomalies of dissolved oxygen exceeded (in absolute value) the corresponding anomalies noted during the period of eutrophication of the Black Sea waters in the last decades of the 20th century. The main reason for the extreme anomalies discovered in the 1920s is the increase in the temperature of the surface layer of the Black Sea waters during this period. [ABSTRACT FROM AUTHOR]

Strain elastography allows the evaluation of tissue elasticity. Background/Objectives: Tissue elasticity depends on the content and distribution of collagen fibers and is shaped by the applied tensile forces that may differ in uteri with a different angle of flexion of the corpus on the cervix. The objective was to investigate whether the angle of uterine flexion is related to cervical tissue elasticity. Methods: The anterior angle between the longitudinal axis of the uterus corpus and that of the cervix was measured in 275 non-pregnant young women by transvaginal ultrasonography and considered both as an absolute value or categorized as ≤150°, between >150° and ≤210°, and >210°. Strain elastography was used to assess tissue elasticity by placing the probe in the anterior vaginal fornix. Tissue elasticity was evaluated in the middle of the anterior cervical compartment (ACC), in the middle of the posterior cervical compartment (PCC), in the middle portion of the cervical canal (MCC), and at the internal cervical os (ICO). In a sagittal plane MCC was evaluated across the cervical canal, and ACC and PCC at a distance equal between the cervical canal and the outer anterior or posterior part of the cervix. MCC, ACC and PCC were evaluated at equal distance between the ICO and the external cervical os. Elasticity was expressed as a color score ranging from 0.1 (low elasticity) to 3 (high elasticity). Results: The angle of uterine flexion show a negative linear relation with the elasticity of the ACC (p = 0.001) and MCC (p = 0.002) and a positive relation with the elasticity of the PCC (p = 0.054). In comparison to uteri with an angle of flexion of <150°, those with an angle of flexion of >210° had lower elasticity of the ACC (p = 0.001) and MCC (p = 0.001) and higher elasticity of the PCC (p = 0.004). The ACC/PCC and PCC/MCC elasticity ratios were also significantly different (p = 0.001). Conclusions: The angle of uterine flexion is associated with changes in cervix elasticity. Retroflexion is associated with stiffer ACC and MCC and a more elastic PCC. Differences in tissue elasticity suggest structural changes of the cervix that may have implication in variate obstetric and gynecological conditions. [ABSTRACT FROM AUTHOR]

Simpson inequalities for first-order differentiable convex functions and various fractional integrals have been studied extensively. However, Simpson type inequalities for twice-differentiable functions are researched slightly. Therefore, in the present paper, we endeavor to study fractional inequalities of Simpson type for twice-differentiable convex functions. To achieve this goal, we establish a new twicedifferentiable Simpson's identity by using tempered fractional integral operators. Based upon it, we prove several fractional Simpson type inequalities whose second derivatives in absolute value are convex. Finally, we give some examples to illustrate the correctness of the obtained results. [ABSTRACT FROM AUTHOR]

Text processing tasks commonly grapple with the challenge of high dimensionality. One of the most effective solutions to this challenge is to preprocess text data through feature selection methods. Feature selection can select the most advantageous features for subsequent operations (e.g., classification) from the native feature space of the text. This process effectively trims the feature space's dimensionality, enhancing subsequent operations' efficiency and accuracy. This paper proposes a straightforward and efficient filter feature selection method based on document-term matrix unitization (DTMU) for text processing. Diverging from previous filter feature selection methods that concentrate on scoring criteria definition, our method achieves more optimal feature selection by unitizing each column of the document-term matrix. This approach mitigates feature-to-feature influence and reinforces the role of the weighting proportion within the features. Subsequently, our scoring criterion subtracts the sum of weights for negative samples from positive samples and takes the absolute value. We conduct numerical experiments to compare DTMU with four advanced filter feature selection methods: max–min ratio metric, proportional rough feature selector, least loss, and relative discrimination criterion, along with two classical filter feature selection methods: Chi-square and information gain. The experiments are performed on four ten-thousand-dimensional feature space datasets: b o o k , d v d , m u s i c , m o v i e and two thousand-dimensional feature space datasets: i m d b , a m a z o n _ c e l l s , sourced from Amazon product reviews and movie reviews. Experimental findings demonstrate that DTMU selects more advantageous features for subsequent operations and achieves a higher dimensionality reduction rate than those of the other six methods used for comparison. Moreover, DTMU exhibits robust generalization capabilities across various classifiers and dimensional datasets. Notably, the average CPU time for a single run of DTMU is measured at 1.455 s. • This paper offers DTMU, a filter feature selection method enhancing feature quality via unitization for improved properties. • DTMU is notably user-friendly, involving only two straightforward steps. • This paper substantiates, through numerical experiments, that DTMU stands as an advanced and effective method. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the nonlinear least squares problem: \min _{{\boldsymbol {x}}\in \mathbb {H}^d}\|\lvert A{\boldsymbol {x}}\rvert -{\boldsymbol {b}}\| where A\in \mathbb {H}^{m\times d}, {\boldsymbol {b}}\in \mathbb {R}^m with \mathbb {H}\in \left \{\mathbb {R},\mathbb {C}\right \} and consider the uniqueness and stability of solutions. This problem arises in applications such as phase retrieval and absolute value rectification neural networks. While several results have been developed to characterize the uniqueness and stability of solutions when {\boldsymbol {b}}=\lvert A{\boldsymbol {x}}_0\rvert for some {\boldsymbol {x}}_0\in \mathbb {H}^d, no existing results address the case where {\boldsymbol {b}} is arbitrary. In this paper, we investigate the uniqueness and stability of solutions for the more general case where {\boldsymbol {b}} is not necessarily equal to \lvert A{\boldsymbol {x}}_0\rvert for any {\boldsymbol {x}}_0\in \mathbb {H}^d. We prove that for any matrix A\in \mathbb {H}^{m\times d}, there is always a vector {\boldsymbol {b}}\in \mathbb {R}^m for which the solution to the nonlinear least squares problem is not unique. However, we show that such "bad" vectors {\boldsymbol {b}} are negligible in practice; specifically, if {\boldsymbol {b}}\in \mathbb {R}_{ }^m does not lie in some measure zero set, then the solution is unique. Furthermore, we establish certain conditions under which the solution is guaranteed to be unique. Regarding the stability of solutions, we prove that the solution is not uniformly stable. However, if we restrict the vectors {\boldsymbol {b}} to a convex set where the solution to the least squares problem is unique, then the solution becomes stable. To the best of our knowledge, our results represent the first theoretical results of the uniqueness and stability of solutions for the nonlinear least squares problem. [ABSTRACT FROM AUTHOR]

The overpressure propagation characteristics of gas cloud explosion are analyzed. The spatial propagation of pressure wave appears to be self-similar. Due to the acoustic property, the absolute values of overpressure peak and impulse peak all decrease in inverse proportion rule. The built-in obstacle could cause the remarkable increase of positive overpressure peak and the absolute value of negative overpressure peak is always lower than that of positive parameter. With pressure wave propagating, the time reaching the positive overpressure peak decreases gradually. The time τ and the distance δ to form a shock front decrease with the increase of pressure wave intensity. However, τ remains constant and δ turns to rise as the pressure intensity increases continually. The positive overpressure duration time remains constant during propagation. For unconfined gas cloud explosion, the integral of overpressure against time is equal to zero and I max and I min basically share the same absolute value. • The overpressure propagation characteristics of gas cloud explosion are analyzed. • The spatial propagation of pressure wave appears to be self-similar. • The pressure wave tends to form a shock front. • Positive overpressure duration time keeps constant during propagation. • Positive and negative overpressure impulse peak share the same absolute value. [ABSTRACT FROM AUTHOR]

Study design. Retrospective cohort study. Objective. To investigate the impact of long symptom duration (>24 mo) on patient self-reported outcomes for pain, function, and quality of life following anterior cervical discectomy and fusion (ACDF) for cervical radiculopathy. Summary of Background Data. ACDF is an effective treatment to relieve the symptoms of cervical radiculopathy. However, there is no consensus on whether prolonged preoperative length of symptoms negatively impacts postoperative outcomes. Methods. This study included consecutive patients who underwent ACDF for cervical radiculopathy from May 1, 2012 to Dec 1, 2019 by a single surgeon. Patients were stratified by short (<24 mo) and long (> 24 mo) duration of symptoms. Outcomes including visual analog scale (VAS) neck and arm, neck disability index (NDI), EuroQol-5D (EQ-5D), and overall state of health (EQVAS) were compared between cohort both for absolute values and percentage of patients achieving minimal clinically important difference. Results. A total of 111 consecutive patients were included in our study, including 59 patients in the short symptom duration group and 52 patients in the long symptom duration group. The mean age of the patients was 51.4 ± 9.4 and 41 (36.9%) were female. The baseline VAS neck and arm, NDI, EQ-5D, and EQVAS were similar between groups. Patients in both long and short symptom duration groups had clinical improvement following surgery. However, patients with short symptom duration had better VAS Neck and EQ-5D outcomes, and were more likely to meet minimal clinically important difference for NDI, EQ-5D, or any outcome. Multivariate analysis confirmed symptom duration <24 months as an independent predictor for better patientreported outcomes. Conclusion. We appreciated better clinical outcomes in patients with shorter symptom duration who received ACDF for cervical radiculopathy. On the basis of this data, we advocate for prompt treatment of cervical radiculopathy to avoid the potential for longterm impairment. [ABSTRACT FROM AUTHOR]

Augmented reality (AR) has been used for navigation during total hip arthroplasty (THA). AR computed tomography (CT)-based navigation systems and AR-based portable navigation systems that use smartphones can also be used. This study compared the accuracy of cup insertion during THA using AR-CT-based and portable AR-based navigation systems. Patients with symptomatic hip disease who underwent primary THA in the supine position using both AR CT-based and portable AR-based navigation systems simultaneously between October 2021 and July 2023 were included. The primary outcome of this study was the absolute difference between cup angles in the intraoperative navigation record and those measured on postoperative CT. The secondary outcome was to determine the factors affecting the absolute value of the navigation error in radiographic inclination (RI) and radiographic anteversion (RA) of the cup, including sex, age, body mass index, left or right side, approach, and preoperative pelvic tilt. This study included 94 consecutive patients. There were 11 men and 83 women, with a mean age of 68 years. The mean absolute errors of RI were 2.7° ± 2.0° in the AR CT-based and 3.3° ± 2.4° in the portable AR-based navigation system. The mean absolute errors of RA were 2.5° ± 2.1° in the AR CT-based navigation system and 2.3° ± 2.2° in the portable AR-based navigation system. No significant differences were observed in RI or RA of the cup between the two navigation systems (RI: p = 0.706; RA: p = 0.329). No significant factors affected the absolute value of the navigation errors in RI and RA. In conclusion, there were no differences in the accuracy of cup insertion between the AR CT-based and portable AR-based navigation systems. [ABSTRACT FROM AUTHOR]

In this work, density-functional theory (DFT) was used to investigate the geometry and electronic structure of Run(n = 1–6,10) supported on CeO2(110) (Run(n = 1–6,10)/CeO2(110)) and their electrocatalytic properties for the N2 reduction reaction (NRR). The results indicated that there is a strong metal–support interaction between Run and CeO2(110), which leads to large surface distortion and stabilized Run. On Run(n = 1–6,10)/CeO2(110), N2 captured in the end-on mode is thermodynamically more favorable than that captured in the side-on mode; however, the side-on mode can lead to stronger activation of N2 which promotes the following protonation step of N2. For Run(n = 3,5,6)/CeO2(110), the electrochemical NRR prefers to occur via an enzymatic mechanism with limiting potentials of −0.31, −0.53 and −0.66 V. The electrocatalytic activity of Run(n = 1–6,10)/CeO2(110) for the NRR shows a strong size dependence. For Ru3/CeO2(110), it has the lowest absolute value of limiting potential, and with the increase in n (n > 3), the limiting potential becomes more negative. Moreover, Ru3/CeO2(110) shows high selectivity and stability. This study gives valuable insights for designing effective catalysts for the NRR. [ABSTRACT FROM AUTHOR]

Purpose: This study presents a two-step numerical iteration method specifically designed to solve absolute value equations. The proposed method is valuable and efficient for solving absolute value equations. Several numerical examples were taken to demonstrate the accuracy and efficiency of the proposed method. Design/methodology/approach: We present a two-step numerical iteration method for solving absolute value equations. Our two-step method consists of a predictor-corrector technique. The new method uses the generalized Newton method as the predictor step. The four-point open Newton-Cotes formula is considered the corrector step. The convergence of the proposed method is discussed in detail. This new method is highly effective for solving large systems due to its simplicity and effectiveness. We consider the beam equation, using the finite difference method to transform it into a system of absolute value equations, and then solve it using the proposed method. Findings: The paper provides empirical insights into how to solve a system of absolute value equations. Originality/value: This paper fulfills an identified need to study absolute value equations. [ABSTRACT FROM AUTHOR]

If primitive arc magmas are primarily oxidized or if they acquire their oxidizing character during crustal evolution remains debated. Mineral-melt V partitioning is extremely redox sensitive and has the potential to resolve this debate, but critical low-temperature, hydrous experimental partitioning data are limited. We present new experimental V partitioning data for olivine-melt, spinel-melt, and clinopyroxene-melt based on the ≤ 1200 °C, hydrous basalt phase equilibrium experiments of Pichavant et al. (Geochim Cosmochim Acta 66:2193–2209, 2002) and Pichavant and Macdonald (Contrib Mineral Petrol 154:535–558, 2007). Combined with published experimental data, we use our olivine-melt V partitioning coefficients to show that—contrary to previous conclusions—hydrous melt composition, i.e. melt H2O concentration in addition to the concentration of other melt components, affects V partitioning and thus calculated fO2, systematically overestimating fO2 for olivine-melt equilibrated at high melt H2O concentration. False absolute fO2 values and false oxidation or reduction trends may be inferred. Based on these findings, we have calibrated a set of new olivine-melt oxybarometers applicable to hydrous arc magmas partially crystallized at ~ 1025–1350 °C. In a case study on a high-Mg basalt from St. Vincent, Lesser Antilles, we show that olivine-melt V oxybarometry records oxidizing near-liquidus conditions (~ QFM + 1.8) and possibly limited oxidation (~ 0.3 log units) during intermittent crustal magma storage. [ABSTRACT FROM AUTHOR]

Competitiveness in the global market is getting more intense. Due to resource and budget constraints, firms need to achieve their expected goals and satisfy all investment constraints under uncertainty. Selecting the set of projects among other candidates to get the most efficient portfolio requires a lot of attention from the Decision Makers (DMs) as this consideration no longer relies purely on the financial term. This problem becomes a multi-objective problem under uncertainty where the financial return and risk from uncertainty are required into the trading off consideration. Due to the financial uncertainty, the chance-constrained programming has been employed in this study for defuzzifying and solving uncertain optimization problems at a specified confidence level that is defined by the DMs. Then, various kinds of investment or financial risk measures, Lower-Semi Variance Index (LSVI), the absolute deviation with the expected FNPV, and the absolute mean-Conditional Value at Risk (CVaR) gap are provided in the selection of such risk measures to show their differences in characteristics and performances in the obtained results. Since, such problems can consist of many project candidates and complex constraints, which may grow beyond the application of the exact optimization approach, a meta-heuristic method, Genetic Algorithm (GA), is introduced to optimize this problem through designing and constructing a decision support tool for the investment portfolio selection and optimization. The applicability of the proposed comparative approach and the constructed tool are illustrated through examples. [ABSTRACT FROM AUTHOR]

The leakage flow has a significant impact on the aerodynamic losses and efficiency of the compressor. This paper investigates the loss mechanism in the tip region based on a high-load cantilevered stator cascade. Firstly, a high-fidelity flow field structure was obtained based on the Enhanced Delay Detached Eddy Simulation (EDDES) method. Subsequently, the Liutex method was employed to study the vortex structures in the tip region. The results indicate the presence of a tip leakage vortex (TLV), passage vortex (PV), and induced vortex (IV) in the tip region. At i = 4 ° , 8 ° , the induced vortex interacts with the PV and low-energy fluid, forming a "three-shape" mixed vortex. Finally, a qualitative and quantitative analysis of the loss sources in the tip flow field was conducted based on the entropy generation rate, and the impact of the incidence on the losses was explored. The loss sources in the tip flow field included endwall loss, blade profile loss, wake loss, and secondary flow loss. At i = 0 ° , the loss primarily originated from the endwall and blade profile, accounting for 40 % and 39 % , respectively. As the incidence increased, the absolute value of losses increased, and the proportion of loss caused by secondary flow significantly increased. At i = 8 ° , the proportion of secondary flow loss reached 47%, indicating the most significant impact. [ABSTRACT FROM AUTHOR]

Using Tokuda's improved linear combination operator method and variational technique, the expression of the polaron effective mass in a parabolic quantum well is derived. Due to the spin-orbit interaction, the effective mass ratio of polaron splits into two branches. The dependence of the effective mass ratio on the vibration frequency, the spin-orbit coupling parameter, and the velocity is discussed by numerical calculation in the presence and absence of phonon. The effective mass ratio of polaron is an increasing function of vibration frequency. The absolute value of the spin splitting effective mass ratio increases with the increase in the spin-orbit coupling parameter and decreases with the increase in velocity. Due to the heavy hole characteristic of spin-orbit interaction, the spin splitting effective mass ratio is negative. The effective mass ratio is larger in the presence of a phonon than in the absence of a phonon, and the effective mass ratio splitting distance is independent of the phonon. [ABSTRACT FROM AUTHOR]

In this article, the direct current (DC) motor control approach is presented using the sand cat swarm optimization (SCSO) method to obtain the best proportional integral derivative (PID) parameters. DC motors are popular equipment. In addition, DC motors are easy to apply. SCSO is a method that adopts the desert cat's life in nature when searching for prey. This cat is able to detect low frequencies below 2 kHz and also has an extraordinary ability to dig for prey. This research was carried out using the MATLAB/Simulink application. To obtain the performance of the SCSO method, a comparison method was used, namely particle swarm optimization (PSO), gray wolf optimizer (GWO), whale optimization algorithm (WOA), and aquila optimizer (AO). From the results of the study, it was found that the settling time value and integral total weighted absolute value error (ITAE) value of the SCSO method were the best compared to other methods. [ABSTRACT FROM AUTHOR]

Suppose A = { a 1 , ... , a n + 2 } ⊂ Z n has cardinality n + 2 , with all the coordinates of the a j having absolute value at most d, and the a j do not all lie in the same affine hyperplane. Suppose F = (f 1 , ... , f n) is an n × n polynomial system with generic integer coefficients at most H in absolute value, and A the union of the sets of exponent vectors of the f i . We give the first algorithm that, for any fixedn, counts exactly the number of real roots of F in time polynomial in log (d H) . We also discuss a number-theoretic hypothesis that would imply a further speed-up to time polynomial in n as well. [ABSTRACT FROM AUTHOR]

Roller bearings are critical components in various mechanical systems, and the timely detection of potential failures is essential for preventing costly downtimes and avoiding substantial machinery breakdown. This research focuses on finding and verifying a robust method that can detect failures early, without creating false positive failure states. Therefore, this paper introduces a novel algorithm for the early detection of roller bearing failures, particularly tailored to high-precision bearings and automotive test bed systems. The featured method (AFI—Advanced Failure Indicator) utilizes the Fast Fourier Transform (FFT) of wideband accelerometers to calculate the spectral content of vibration signals emitted by roller bearings. By calculating the frequency bands and tracking the movement of these bands within the spectra, the method provides an indicator of the machinery's health, mainly focusing on the early stages of bearing failure. The calculated channel can be used as a trend indicator, enabling the method to identify subtle deviations associated with impending failures. The AFI algorithm incorporates a non-static limit through moving average calculations and volatility analysis methods to determine critical changes in the signal. This thresholding mechanism ensures the algorithm's responsiveness to variations in operating conditions and environmental factors, contributing to its robustness in diverse industrial settings. Further refinement was achieved through an outlier detection filter, which reduces false positives and enhances the algorithm's accuracy in identifying genuine deviations from the normal operational state. To benchmark the developed algorithm, it was compared with three industry-standard algorithms: VRMS calculations per ISO 10813-3, Mean Absolute Value of Extremums (MAVE), and Envelope Frequency Band (EFB). This comparative analysis aimed to evaluate the efficacy of the novel algorithm against the established methods in the field, providing valuable insights into its potential advantages and limitations. In summary, this paper presents an innovative algorithm for the early detection of roller bearing failures, leveraging FFT-based spectral analysis, trend monitoring, adaptive thresholding, and outlier detection. Its ability to confirm the first failure state underscores the algorithm's effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, we construct a new class of convex functions, so-called generalized n-polynomial p-convex functions. We investigate their algebraic properties and provide some relationships between these functions and other types of convex functions. We establish Hermite–Hadamard (H–H) inequality for the newly defined class of functions. Additionally, we derive refinements of H–H inequality for functions whose first derivatives in absolute value at certain power are generalized n-polynomial p-convex. When p = − 1 , our definition evolves into a new definition for the class of convex functions so-called generalized n-polynomial harmonically convex functions. The results obtained in this study generalize regarding those found in the existing literature. By extending these particular types of inequalities, the objective is to unveil fresh mathematical perspectives, attributes and connections that can enhance the evolution of more resilient mathematical methodologies. This study aids in the progression of mathematical instruments across diverse scientific fields. [ABSTRACT FROM AUTHOR]

Delivery e-bicyclists are vulnerable traffic participants, and delivery e-scooter crashes annually cause great losses. There are limited empirical analyses performed to characterize the endogenous and exogenous influences of potential factors on delivery e-scooter crash severities. This study focused on identifying the heterogeneous impacts of contributing factors. Based on 3064 police-reported delivery e-scooter crashes, different potential factors selected from seven perspectives were examined. Combining the latent class clustering analysis and the partial proportional odds model, an unsupervised learning approach was developed to modeling the heterogeneities as well as the corresponding marginal effects. According to the AIC, BIC, and entropy-based approach, the most appropriate number of clusters was identified as three. The model results revealed that the top six factors significantly influencing the injury severities were running red light, reverse riding, speeding, bike lane, changing lane, and e-bicyclist age. Their maximum absolute values of the marginal effects were more than 29%. The sub-models owned a better goodness of fit in characterizing heterogeneities and avoiding the model bias. It was easy to find the remarkable heterogeneities within each factor and across different clusters. The findings could provide insightful guidance and effective recommendations for alleviating the crash losses and promoting rider safety. [ABSTRACT FROM AUTHOR]

This paper established the idea of minimum evdominating matrix of semigraph and calculated its energy. The minimum ev-dominating energy EmeD(G) of a semigraph G is the sum of the absolute values of the eigenvalues of the minimum ev-dominating matrix. Here some results are also derived in connection with the energy of minimum evdominating matrix. Some lower bounds are also established. [ABSTRACT FROM AUTHOR]

A chain graph is a bipartite graph in which the neighborhood of the vertices in each partite set forms a chain with respect to set inclusion. By extending the concept of nesting from a bipartite graph to a k partite graph, a k-nested graph is defined. A half graph is a chain graph having no pairs of duplicate vertices. Similarly, a 'k-half graph' is a class of knested graph with no pairs of duplicate vertices. The (first) Zagreb matrix or Z-matrix denoted by Z(G) = (zij)n×n of a graph G, whose vertex vi has degree di is defined by zij = di + dj if the vertices vi and vj are adjacent and zij = 0 otherwise. Let ζ1, ζ2, . . ., ζn be the Zagreb eigenvalues of Z(G) and the Zagreb energy is the sum of the absolute values of the Zagreb eigenvalues. We obtain the determinant, eigenvalues and inverse of a k-half graph with respect to the Z-matrix. Bounds for the Zagreb energy and spectral radius are discussed along with the main and non-main Zagreb eigenvalues of a k-half graph. [ABSTRACT FROM AUTHOR]

Wait time for surgeries can be lengthy and its effect on postoperative outcome remains largely unknown. We evaluated the effect of wait time on postoperative outcome and on clinical course while awaiting surgery for lumbar spinal stenosis. This was a retrospective cohort study. A convenience sample (n=134) from prospective longitudinal studies that provided preoperative Oswestry Disability Index (ODI) data at two different time points and follow-up of ≥12 months. Wait time was the period between the initial consultation and immediately preoperatively. The primary outcome was the ODI minimal clinically important difference (MCID) (<30% vs ≥30% improvement) at 1 year. The median wait time was 5.9 (interquartile range (IQR) 8.2) months and postoperative follow-up was 19.2 (IQR 8.1) months. Wait time was not associated with absolute postoperative change in ODI scores, but patients with wait times <12 months were significantly more likely to reach the ODI MCID at last follow-up (66 (73.3%) for <12 months versus 13 (46.4%) for ≥12 months, p=.008; odds ratio=0.29 (95% confidence interval 0.12–0.75), p=.011). During wait time, there was no difference in patients deteriorating above the MCID for each time point (10 [9.7%] versus 5 [16.1%], p=.320). Longer wait times did not negatively influence postoperative outcome in patients with lumbar spinal stenosis using absolute values, but may impact individual patients' ability to achieve MCID. Patient-reported pain-related disability from the initial surgical consultation to surgery is relatively stable in most patients for at least 6 to 12 months. [ABSTRACT FROM AUTHOR]

We consider a mathematical model of the initiation and development of atherosclerosis in the early stage, defined in different domains. The existence of nonnegative weak solutions is proved via studying an auxiliary system with absolute value terms and applying a novel semi-discrete, operator splitting numerical scheme. Numerical simulations were performed in an idealized two-dimensional geometry in order to verify our assumptions in model building and theoretical analysis. The framework we developed can also be used for nonlinear reaction–diffusion systems defined in other different domains with more complex coupling conditions. [ABSTRACT FROM AUTHOR]

Physical and flow property tests were carried out on eight pharmaceutical powders. The results obtained from heap analysis and shear cell testing have been compared. A relationship to represent the static angle of repose has been developed using a bulk powder-based Froude number and fine size. The experimental results and predictions for a range of bulk properties have shown that the values of static angle of repose decrease with an increase in the value of bulk powder Froude number, increase in particle shape factor and decrease in the median to fine ratio. Out of all the dimensionless parameter groupings, the particle shape factor strongly influences the static angle of repose, as indicated by its larger absolute value of the exponent in the power function format relationship. The relationship can be used as a techno-economic optimization tool for particle processing/synthesis while maintaining the desired powder flowability. [ABSTRACT FROM AUTHOR]

The paper presents monitoring of spatial displacements and deformation of hydraulic structures of hydroelectric power plants of the Dnipro and Dnister cascades using permanent deformation monitoring systems (PDMS). The architecture of the geodetic (measuring) component of monitoring systems deployed at Kaniv, Dnipro, Seredniodniprovska and Dnister HPP (all in Ukraine) are presented, as well as deformation monitoring structure of this systems. Analysis of the impact of geodynamic and seismic factors on the operation of selected monitoring systems are presented. The spatial deformations of the base points on all the studied monitoring systems were determined. As a result of the analysis of the obtained values, it was found that the deformations of the dam crest have a seasonal nature (with half-annual period) of movements, and are characterized by the corresponding vector field and the absolute value of spatial movements. [ABSTRACT FROM AUTHOR]

Time series forecasting is an important application of many statistical methods. When it is appropriate to assume that the data may be projected towards the future based on the past history of the dataset, a preliminary examination is usually required to ensure that the data sequence is autocorrelated. This is a quite obvious assumption that has to be made and can be the object of a formal test of hypotheses. The most widely used test is the portmanteau test, i.e., a sum of the squared standardized autocorrelations up to an appropriate maximum lag (the truncation point). The choice of the truncation point is not obvious and may be data-driven exploiting supplementary information, e.g. the largest autocorrelation and the lag where such maximum is found. In this paper, we propose a portmanteau test with a truncation point equal to the lag of the largest (absolute value) estimated autocorrelation. Theoretical and simulation-based comparisons based on size and power are performed with competing portmanteau tests, and encouraging results are obtained. [ABSTRACT FROM AUTHOR]

The distance energy of a connected graph G is the sum of absolute values of the eigenvalues of the distance matrix of G. In this paper, we study how the distance energy of the complete split graph G S (m , n) = K m + K ¯ n changes when an edge is deleted from it. The complete split graph G S (m , n) consists of a clique on m vertices and an independent set on n vertices in which each vertex of the clique is adjacent to each vertex of the independent set. We prove that the distance energy of the complete split graph G S (m , n) always increases when an edge is deleted from it. [ABSTRACT FROM AUTHOR]

The main goal here is to introduce another type of fuzzy normed space which we call a convex fuzzy normed space. Moreover, we give important properties of such a space. [ABSTRACT FROM AUTHOR]