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We present the development of a non-reflecting boundary condition, based on the Local One-Dimensional Inviscid (LODI) approach, for Lattice Boltzmann Models working with multi-speed stencils. We test and evaluate the LODI implementation with numerical benchmarks, showing significant accuracy gains with respect to the results produced by a simple zero-gradient condition. We also implement a simplified approach, which allows handling the unknown distribution functions spanning several layers of nodes in a unified way, still preserving a comparable level of accuracy with respect to the standard formulation.

When a malfunction occurs in a marine main engine system, the impact of the anomaly will propagate through the system, affecting the performance of all relevant components in the system. The phenomenon of fault propagation in the system caused by induced factors can interfere with fault localization, making the latter a difficult task to solve. This paper aims at showing how the "characteristic curves method" is able to properly locate malfunctions also when more malfunctions appear simultaneously. To this end, starting from the working principle of each component of a real marine diesel engine system, comprehensive and reasonable thermal performance parameters are chosen to describe their characteristic curves and include them in a one-dimensional thermodynamic model. In particular, the model of a low-speed two stroke MAN 6S50 MC-C8.1 diesel engine is built using the AVL Boost software and obtaining errors lower than 5% between simulated values and test bench data. The behavior of the engine is simulated considering eight multi-fault concomitant phenomena. On this basis, the fault diagnosis method proposed in this paper is verified. The results show that this diagnosis method can effectively isolate the fault propagation phenomenon in the system and quantify the additional irreversibility caused by the Induced factors. The fault diagnosis index proposed in this paper can quickly locate the abnormal components.

To simplify the characterization of wood species, the Brazilian standard document ABNT NBR 7190-1 (2022) establishes the determination of mechanical properties employing the characteristic strength in the compression parallel to grain (fc0,k). This mechanical property is estimated using the linear relation given by the following expression fv0,k = 0.12·fc0,k Brazilian and European standard documents support the estimation of fv0,k using relations among properties. However, the European guidelines in the EN 384 (2019) have used the conventional characteristic strength in the static bending test (fM,k). Thus, this study aimed to investigate the efficiency of the ratio fv0,k = 0.12·fc0,k for adopting 30 hardwoods. The variance analysis results demonstrate the divergence among the experimental outcomes and those values estimated using the relation cited. Therefore, regression models at two parameters were considered to obtain more accurate estimates of fv0,k by adopting fc0,k, and fM,k as independent variables. Regarding the results, the geometric (R² = 80.80%) and linear (R² = 74.19%) models were the most accurate for the estimates of fv0,k in terms of fc0,k, and fM,k, respectively. This fact evinces the good accuracy of the models under consideration, which may provide a more rigorous structural design compared to the correlation currently prescribed by the ABNT NBR 7190-1 (2022). RESUMO Para simplificar a caracterização de espécies de madeira, o documento normativo brasileiro ABNT NBR 7190-1 (2022) estabelece a determinação de propriedades mecânicas por meio da resistência característica na compressão paralela às fibras (fc0,k). Essa propriedade mecânica é estimada utilizando-se da relação linear dada pela expressão a seguir fv0,k = 0.12·fc0,k. Ambos os documentos normativos europeu e brasileiro prescrevem a estimativa da fv0,k empregando-se relações entre propriedades, embora as diretrizes da europeia contidas na EN 384 (2019) utilize a resistência característica convencional obtida no teste de flexão estática (fM,k). Assim, esse estudo teve o objetivo de investigar a eficiência da relação fv0,k = 0.12·fc0,k para 30 espécies folhosas. Os resultados da análise de variância demonstram a divergência entre os resultados experimentais e aqueles estimados utilizando-se da relação citada. Portanto, modelos de regressão em função de dois parâmetros foram considerados para se obter estimativas mais precisas da fv0,k através da adoção da fc0,k e fM,k como variáveis independentes. Com relação aos resultados, os modelos geométrico (R² = 80.80%) e linear (R² = 74.19%) foram os mais precisos para a estimativa da fv0,k em termos da fc0,k e fM,k, respectivamente. Este fato evidencia a boa precisão dos modelos em questão, o que pode proporcionar um dimensionamento estrutural mais rigoroso quando comparado à correlação atualmente prescrita pela ABNT NBR 7190-1 (2022).

Summary Recent developments in predicting microemulsion phase behavior for use in chemical flooding are based on the hydrophilic-lipophilic deviation (HLD) and net-average curvature (NAC) equation-of-state (EoS). The most advanced version of the HLD-NAC EoS assumes that the three-phase micelle characteristic length is constant as parameters like salinity and temperature vary. In this paper, we relax this assumption to improve the accuracy and thermodynamic consistency of these flash calculations. We introduce a variable characteristic length in the three-phase region based on experimental data that is monotonic with salinity or other formulation variables, such as temperature and pressure. The characteristic length at the boundary of the three-phase region is then used for flash calculations in the two-phase lobes for Winsor type II-/II+. The functional form of the characteristic length is made consistent with the Gibbs phase rule. The improved EoS can capture asymmetric phase behavior data around the optimum, whereas current HLD-NAC based models cannot. The variable characteristic length formulation also resolves the thermodynamic inconsistency of existing phase behavior models that give multiple solutions for the optimum. We show from experimental data and theory that the inverse of the characteristic length varies linearly with formulation variables. This important result means that it is easy to predict the characteristic length in the three-phase region, which also improves the estimation of surrounding two-phase lobes. This improved physical understanding of microemulsion phase behavior should greatly aid in the design of surfactant blends and improve recovery predictions in a chemical flooding simulator.

We extend to characteristic $2$ and $3$ the classification of projective homogeneous varieties of Picard group isomorphic to $\mathbf{Z}$, corresponding to parabolic subgroup schemes with maximal reduced subgroup. The latter are all obtained as product of a maximal reduced parabolic with the kernel of a purely inseparable isogeny. This fails in type $G_2$ and characteristic $2$, for which we exhibit an explicit counterexample and show it is the only one, thus completing the classification. We then construct new examples of projective homogeneous varieties of Picard rank two.

Let $k$ be a field of characteristic two. We prove that a non constant monic polynomial $f\in k[X]$ of degree $n$ is the minimal/characteristic polynomial of a symmetric matrix with entries in $k$ if and only if it is not the product of pairwise distinct inseparable irreducible polynomials. In this case, we prove that $f$ is the minimal polynomial of a symmetric matrix of size $n$. We also prove that any element $\alpha\in k_{alg}$ of degree $n\geq 1$ is the eigenvalue of a symmetrix matrix of size $n$ or $n+1$, the first case happening if and only if the minimal polynomial of $\alpha$ is not the product of pairwise distinct inseparable irreducible polynomials.

While it is generally accepted that quantum mechanics is a probability theory, its methods differ radically from standard probability theory. We use the methods of quantum mechanics to understand some fundamental aspects of standard probability theory. We show that wave functions and operators do appear in standard probability theory. We do so by generalizing the Khintchine and Bochner criteria for a complex function to be a characteristic function. We show that quantum mechanics clarifies these criteria and suggests generalizations of them.

Electromagnetic spring active isolators have attracted extensive attention in recent years. The standard Bouc–Wen model is widely used to describe hysteretic behavior but cannot accurately describe asymmetric behavior. The standard Bouc–Wen model is improved to better describe the dynamic characteristic of a toothed electromagnetic spring. The hysteresis model of toothed electromagnetic spring is established by adding mass, damping, and asymmetric correction terms with direction. Subsequently, the particle swarm optimization algorithm is used to identify the parameters of the established model, and the results are compared with those obtained from the experiment. The results show that the current has a significant impact on the dynamic curve. When the current increases from 0.5 A to 2.0 A, the electromagnetic force sharply increases from 49 N to 534 N. Under different excitations and currents, the residual points predicted by the model proposed in this work fall basically in the horizontal band region of −20–20 N (for an applied current of 1.0 A) and −40–80 N (for an application of 4.5 mm/s). Furthermore, the maximum relative error of the model is 12.75%. The R2 of the model is higher than 0.98 and the highest value is 0.9993, proving the accuracy of the established model.

Motivation: * Transmission lines are used as interconnects in discrete (PCB) and integrated circuits. * They have been employed as such for several decades. * And even though they are very simple structures, determining their characteristic impedance (Zc) is not straightforward. * This is because, in order to be measured, probing platforms and probes are needed. * These introduce two more structures to the setup on either port. * Characterizing these additional components is a must to obtain reliable values for Zc.

In the context of the rapid development of the Internet and the Internet of Things technology, services based on location information have received more and more attention, and people gradually have higher expectations for the quality and experience of positioning services. At present, outdoor positioning technology is becoming mature, but different from empty outdoor areas, there is a highly complex indoor environment with many interference factors, so it is difficult to receive effective satellite signals. To realize the smooth transition of whole-field positioning, it is necessary to study an economical and efficient indoor positioning technology. The existing indoor positioning technologies have some problems, so this paper comprehensively uses the resource-rich Wi-Fi signal, Frequency Modulation (FM) signal and Digital Terrestrial Multimedia Broadcast (DTMB) signal as the positioning data sources, and proposes a fingerprint fusion positioning method based on the wireless signal distribution characteristic. Experiments show that the proposed method improves localization accuracy by 30% compared to localization with Wi-Fi alone.

A splinter is a notion of singularity that has seen numerous recent applications, especially in connection with the direct summand theorem, the mixed characteristic minimal model program, Cohen-Macaulayness of absolute integral closures and cohomology vanishing theorems. Nevertheless, many basic questions about these singularities remain elusive. One outstanding problem is whether the splinter property spreads from a point to an open neighborhood of a noetherian scheme. Our paper addresses this problem in prime characteristic, where we show that a locally noetherian scheme that has finite Frobenius or that is locally essentially of finite type over a quasi-excellent local ring has an open splinter locus. In particular, all varieties over fields of positive characteristic have open splinter loci. Intimate connections are established between the openness of splinter loci and $F$-compatible ideals, which are prime characteristic analogues of log canonical centers. We prove the surprising fact that for a large class of noetherian rings with pure (aka universally injective) Frobenius, the splinter condition is detected by the splitting of a single generically \'etale finite extension. We also show that for a noetherian $\textbf{N}$-graded ring over a field, the homogeneous maximal ideal detects the splinter property., Comment: Comments welcome, minor updates in v2

A novel method of designing a wideband high-isolated dual-antenna pair using dual-characteristic modes (CMs) is presented for fifth-generation (5G) multiple-input multiple-output (MIMO) smartphone applications. A set of orthogonal CMs resonating from the square-loop slot is first introduced and works for the lower band. Then, another set of orthogonal CMs resonating from the edge branches is introduced with a shared compact radiator and works for the higher band. In combination with two sets of degenerated CMs and a capacitive coupling feeding structure, the proposed dual-antenna pair achieves a broad impedance bandwidth and high isolation without the need for any external decoupling structures. Based on this dual-antenna pair, an 8times 8 MIMO array is developed and integrated into the back cover of a smartphone, which realizes zero ground clearance on the system circuit board. To verify the design concept, prototypes of the antenna pair and MIMO array were fabricated and measured. It shows that experimental results agree well with the simulation results. More importantly, the presented 8times 8 MIMO array has high isolation of more than 20 dB is achieved across the operating band of 3.3-3.8 GHz. This work was supported in part by the National Natural Science Foundation of China under Grant 62071347, in part by the Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/N032497/1 and Grant EP/S005625/1, and in part by the 111 Project of China.

In the conditions of TIG welding, the magnitude of the current is set, but not the voltage of the arc. To determine the arc voltage at a set current, arc length, type of electrode, sharpening angle and others, it is necessary to know the static characteristics of the welding arc. This dependence facilitates the use of simulation modelling methods of welding processes. In the proposed study, the static characteristics of the welding arc in TIG process with 4 types of electrodes were determined experimentally. The magnitude of the current was set in the range of 20 to 200A and the arc voltage was measured. All parameters are measured remotely by a real-time welding monitoring system and transferred to a remote computer via the Internet. Graphs were built based on the recordings, and the numerical results were processed and regression relationships were obtained.

We study the notions of the positive cone, characteristic and C-characteristic in (Krasner) hyperfields. We demonstrate how these interact in order to produce interesting results in the theory of hyperfields. For instance, we provide a criterion for deciding whether certain hyperfields cannot be obtained via Krasner’s quotient construction. We prove that any positive integer (larger than 1) can be realized as the characteristic of some infinite hyperfield and an analogous result for the C-characteristic. Finally, we study the (directed) graph associated with the strict partial order induced by a positive cone in a hyperfield in various examples.

本資料は，地域防災Web「あなたの地域を知ろう」パーツにおける地域特性情報を改訂するにあたり，新たな社会特性・自然特性・災害の危険性の算出方法および結果について報告する．旧版の「あなたの地域を知ろう」パーツでは日本全国で同じような手法に基づき，災害特性を相対評価できる仕組みを実現することに重きを置いたことで，地域の災害特性を十分に考慮することができなかった．本資料では，それを踏まえて旧版と比較し，どのように算出方法を変更したのかという方法論を提示する．なお，新たに算出した社会特性・自然特性・災害の危険性については，「あなたの地域を知ろう」パーツ改訂版において公開している．This paper reports on the new method and results of calculating social characteristics, natural characteristics, and disaster risks for the revision of in the “Regional Characteristic Information Tool” of the Local Disaster-Risk Management through Web Service. The previous version of the “Regional Characteristic Information Tool” was based on the same method for the whole of Japan, and focused on realizing a system for relative evaluation of disaster characteristics, which did not sufficiently consider the disaster characteristics of each region. In this paper, we present the methodology of how we changed the calculation method in comparison with the previous version. The newly calculated social characteristics, natural characteristics, and disaster risks are disclosed in the revised version of the “Regional Characteristic Information Tool”.

In this paper, a self-decoupling method is proposed for antenna arrays by exploring the coupling path through high-order characteristic modes of the antenna elements. Mathematical formulas for coupling energy calculation are developed by combining the equivalent circuit of a receive mode antenna with the characteristic mode theory. With the characteristic mode analysis, radiating mode (RM) and decoupling mode (DM) of the antenna element are identified. An effective loading technique is proposed to enhance the modal significances of the DMs. The coupling between the DMs and the adjacent antenna element is enhanced, while the coupling with the dominant RMs of the antennas is suppressed. Because of the coupling energy dispersion in the DMs, the corresponding unwanted induced currents flowing into the feed ports of antenna element are suppressed, and the port isolations are efficiently improved. The decoupling structure composed of a simple metal ring and an impedance matching layer could be directly introduced into an antenna element, and the radiation performance of the previously optimized antenna element is preserved. Both simulated and measured results demonstrate that the port isolations are improved from 15 dB to 20 dB, and the radiation pattern distortion due to the mutual couplings is eliminated.

The safe and stable operation of power transmission and transformation equipment is the foundation of power grid safety, so the prediction of power transmission and transformation equipment fault is particularly important, and the prediction of the characteristic parameters that affect the equipment fault is the core of fault prediction. In this paper, a method for predicting the characteristic parameters of power transmission and transformation equipment based on combination prediction is presented. According to the correlation analysis results of various parameters, the key prediction input data with high correlation degree with the predicted parameters are extracted automatically, and the method library including multiple single-factor prediction models, multi-factor prediction models and combined prediction models is established. The error checking method is used to automatically select the optimal prediction method, and then the characteristic parameters of the parameter are automatically predicted. The test results show that the multi-factor power transmission and transformation equipment fault feature parameter prediction method can improve the accuracy of prediction, and is of great significance to improve the scientific evaluation of equipment health status and the prediction of equipment fault.

Twelve site models were established based on the analysis of the influence of site conditions on earthquake damage and the influence of the soft soil layer on-site seismic response. The equivalent linearization site seismic response analysis is carried out at different input ground motion levels to discuss the influence of soft soil layer thickness and buried depth. The results show that the characteristic period of the response spectrum exhibits a gradual increase as the buried depth or thickness of the soft soil layer increases. Furthermore, the characteristic period of the response spectrum also increases with the rise in the input ground motion peak. Moreover, according to the influence characteristics of soft soil thickness, buried depth, and input ground motion intensity on the characteristic period of the site acceleration response spectrum, a method for adjusting the characteristic period of the site acceleration response spectrum with a soft soil layer is put forward.

This paper combines the piecewise Cubic Hermite (CH) interpolation algorithm and the weighted least square support vector machine (WLS-SVM) to improve identification accuracy for marine crafts built based on the characteristic model. The characteristic model is first used to describe the heading dynamics of marine crafts and is a superior model to the traditional response model in both accuracy and complexity. Especially in order to improve identification accuracy, a CH-based data preprocessing strategy is utilized to densify and smooth data for further accurate identification. Subsequently, the combination of the linear kernel function and the Gaussian kernel function is introduced in the conventional WLS-SVM method, which renders global and local performance improvements compared with the conventional WLS-SVM method. Finally, informative maneuvers composed of Zigzag and Sine are carried out to test the performance of the improved identification method. Compared to the conventional LS-SVM method based on the response model, the root mean square error of the proposed CH-MK-WLS-SVM method based on the characteristic model is reduced by an order of magnitude in the presence of sensor noise.

The justification for making a measurement can be sought in asking what decisions are based on measurement, such as in assessing the compliance of a quality characteristic of an entity in relation to a specification limit, SL. The relative performance of testing devices and classification algorithms used in assessing compliance is often evaluated using the venerable and ever popular receiver operating characteristic (ROC). However, the ROC tool has potentially all the limitations of classic test theory (CTT) such as the non-linearity, effects of ordinality and confounding task difficulty and instrument ability. These limitations, inherent and often unacknowledged when using the ROC tool, are tackled here for the first time with a modernised approach combining measurement system analysis (MSA) and item response theory (IRT), using data from pregnancy testing as an example. The new method of assessing device ability from separate Rasch IRT regressions for each axis of ROC curves is found to perform significantly better, with correlation coefficients with traditional area-under-curve metrics of at least 0.92 which exceeds that of linearised ROC plots, such as Linacre’s, and is recommended to replace other approaches for device assessment. The resulting improved measurement quality of each ROC curve achieved with this original approach should enable more reliable decision-making in conformity assessment in many scenarios, including machine learning, where its use as a metric for assessing classification algorithms has become almost indispensable.

In the present paper, the problem of finding the location of the so-called “characteristic point” of flexible footings is revisited. As known, the settlement at the characteristic point is equal to the uniform settlement of the respective rigid footing. The cases of infinitely long strips and circular footings are studied fully analytically. For the case of rectangular footings, analytical results for flexible footings are compared against the respective 3D numerical results for rigid footings; 210 different cases were examined. As shown, the location of the characteristic point may greatly deviate from what it has been proposed in the literature in mid '50s, while it strongly depends on footing shape, as well as on the thickness and the Poisson’s ratio of the compressible medium. Apart from the elastic settlement, the characteristic point is also useful in problems involving the knowledge of the vertical stress increase in the compressible medium due to footing loading, such as the consolidation settlement. In this respect, stress influence factor curves are given for rectangular and circular footings. Finally, the applicability and limitations of the “characteristic point” concept are also discussed.

Rolling element bearing (REB) vibration signals under variable speed (VS) have non-stationary characteristics. Order tracking (OT) and time-frequency analysis (TFA) are two widely used methods for REB fault diagnosis under VS. However, the effect of OT methods is affected by resampling errors and close-order harmonic interference, while the accuracy of TFA methods is mainly limited by time-frequency resolution and ridge extraction algorithms. To address this issue, a novel method based on envelope spectrum fault characteristic frequency band identification (FCFBI) is proposed. Firstly, the characteristics of the bearing fault vibration signal’s envelope spectrum under VS are analyzed in detail and the fault characteristic frequency band (FCFB) is introduced as a new and effective representation of faults. Then, fault templates based on FCFB are constructed as reference for fault identification. Finally, based on the calculation of the correlation coefficients between the envelope spectrum and fault templates in the extended FCFB, the bearing fault can be diagnosed automatically according to the preset correlation coefficient criterion. Two bearing VS experiments indicate that the proposed method can achieve satisfactory diagnostic accuracy. The comparison of OT and TFA methods further demonstrates the comprehensive superiority of the proposed method in the overall consideration of accuracy, diagnostic time, tachometer dependency, and automatic degree.

The voltage and current measurement of the medium-voltage (MV) side are used for the traditional fault location method, which leads to a high installation cost of the measurement and complicated post-operational and maintenance work. A fault location method is proposed based on the distributed measurement at the low-voltage (LV) side. On the analysis of voltage distribution rules and the influence of the distribution transformer on voltage transmission, obvious differences are found in the variation of voltage (phase voltage and sequence voltage) at the LV side for different faults—specifically, the detection sensitivity of the voltage to different faults varies. Therefore, a fault location method for the MV distribution network based on characteristic voltage at the LV side is proposed. Firstly, the characteristic voltage is selected adaptively according to the fault type. The suspected fault path is then determined by the characteristic voltage amplitude of measuring points. Finally, the fault segment is located via the characteristic current of each segment. This method can be applied in combination with the widely used LV measurement equipment such as the power consumption information acquisition system and the intelligent fusion terminal to acquire LV side voltage without adding new measurement devices. The distribution difference of the characteristic voltage at the LV side is applied for accurate fault finding, which is an economical and practical new idea for the fault location of the distribution network. The correctness and effectiveness of the method were verified by the simulation of the IEEE 34 system built in PSCAD/EMTDC and a real distribution network.

International audience; This article reports a procedure to implement as well as to validate non-reflecting boundary conditions applied for turbomachinery simulations, using Navier-Stokes characteristic boundary conditions in a compressible lattice Boltzmann solver. The implementation of both an inlet condition imposing total pressure, total temperature, and flow angles, as well as an outlet condition imposing a static pressure profile that allows the simulation to reach a simplified radial equilibrium, is described within the context of a lattice Boltzmann approach. The treatment at the boundaries relies on the characteristic methodology to derive conditions which are non-reflecting in terms of acoustics and is also compatible with turbulence injection at the inlet. These properties are evaluated on test cases of increasing complexity, ranging from a simple 2D periodic domain to an S-duct stage with turbulence injection.

Introduction: Emphysematous osteomyelitis (EO) is an extremely rare bone infection by gas-forming bacteria with few documented cases in the literature. Our study aims to highlight characteristic imaging features, including the novel use of positron emission tomography-magnetic resonance imaging (PET-MRI) in the diagnosis of this potentially fatal entity. Case: Radiography and computed tomography (CT) of the pelvis were performed due to complaints of persistent back pain in a 36 year old male with history of recent abdominal aorta surgery. Sacroiliac joint aspiration was performed and a follow-up PET-MRI was subsequently performed. Results: Radiography and CT demonstrated bilateral sacroiliitis, osteonecrosis and EO in the bony pelvis. Left sacroiliac joint aspiration identified Staphylococcus aureus as the causative organism. PET-MRI revealed EO with left iliopsoas abscess and abdominal aortic graft infection. The patient's symptoms resolved following antibiotic therapy and image-guided abscess drainage. Conclusion: EO is a lethal variant of osteomyelitis with a dearth of published cases. Pertinent imaging characteristics of EO on radiography, CT and PET-MRI are discussed here, along with a review of the literature surrounding this rare condition.

A characteristic matrix function captures the spectral information of a bounded linear operator in a matrix-valued function. In this article, we consider a delay differential equation with one discrete time delay and assume this equation is equivariant with respect to a compact symmetry group. Under this assumption, the delay differential equation can have discrete wave solutions, i.e. periodic solutions that have a discrete group of spatio-temporal symmetries. We show that if a discrete wave solution has a period that is rationally related to the time delay, then we can determine its stability using a characteristic matrix function. The proof relies on equivariant Floquet theory and results by Kaashoek and Verduyn Lunel on characteristic matrix functions for classes of compact operators. We discuss applications of our result in the context of delayed feedback stabilization of periodic orbits.

Introduction:Nasopharyngeal carcinoma (NPC) is the most common head and neck malignancy in Indonesia and ranks it as the fourth most common among all malignancies in Indonesia. In Indonesia, it is estimated that the incidence of NPC is 6.2 per 100,000 population or 12,000 new cases per year. The initial stage of the NPC is difficult to establish because of location of the hidden nasopharynx. Misdiagnosis often results from a lack of knowledge about the early signs and symptoms of nasopharyngeal carcinoma. Objective:To know the characteristic of NPC patients in Sanglah General Hospital Denpasar period 2016-2020. Methods:This study used a descriptive research design with a cross sectional design with 602 sample, by taking secondary data from the medical records of patients with NPC who were treated at the ENT-KL polyclinic of Sanglah General Hospital Denpasar for the period 2016-2020. Results:Distribution NPC patients based on gender, the most in male group compare to the female (68.44%: 31.56%). the largest age group was in the 41-50 years group as many as 204 people or 33.89%. The most clinical stage group of NPC patients is stage IVA as many as 301 people (50%) with the histopathological type group of undifferentiated carcinomas compare to the other type groups (89.87%). Conclusion:This study found that NPC is more commonly found in males with the majority aged 41-50 years, most commonly found at an advanced stage, was stage IV A with the most histopathological type is undifferentiated carcinoma.

Due to rapid urbanization and industrialization, the gap between urban and rural development has gradually increased. Rural development problems have been a significant topic of discussion, and are related to people's livelihoods. This article built a point-axis-region location driving system to analyze the spatial location differentiation of characteristic villages and towns (CVTS) using the kernel density model, and explored the mechanism of location driving factors with a geographical detector model. The results show that vegetables and fruits are the main types of products in CVTS. They account for 27.60% and 34.68% of all types of products, and occur mainly in the east and central regions of China. Moreover, all point-axis-region driving factors have a significant influence on grain crops. The mean values of driving forces of vegetables and fruits are larger than other types of CVTS, and their values are 0.12 and 0.11. The average driving forces on all CVTS in the northeast are higher than those in other regions, especially the driving forces of vegetables and medicinal crops (0.24 and 0.18, respectively). Finally, we proposed that the Chinese government should employ engineering technology, invest on road networks, e-commerce and blockchain technology to optimize the point-axis-region location advantages, to promote the sustainable development of CVTS. The detection of driving mechanisms on spatial location differentiation of CVTS has important research value for location theory and rural region systems research.

The Tsallis $q$-Gaussian distribution is a powerful generalization of the standard Gaussian distribution and is commonly used in various fields, including non-extensive statistical mechanics, financial markets and image processing. It belongs to the $q$-distribution family, which is characterized by a non-additive entropy. Due to their versatility and practicality, $q$-Gaussians are a natural choice for modeling input quantities in measurement models. This paper presents the characteristic function of a linear combination of independent $q$-Gaussian random variables and proposes a numerical method for its inversion. The proposed technique makes it possible to determine the exact probability distribution of the output quantity in linear measurement models, with the input quantities modeled as independent $q$-Gaussian random variables. It provides an alternative computational procedure to the Monte Carlo method for uncertainty analysis through the propagation of distributions., 19 pages

Lead is the main toxic factor in jarosite residue. It is important to study the release behavior of lead from simulated lead-bearing jarosite (SLBJ) for predicting the stability of jarosite residue and its secondary pollution to the environment. To identify the technical issues and limitations associated with its safe disposal, a comprehensive analysis of the chemical, structural, and morphological characteristics of SLBJ was conducted using various detection techniques including XRF, XRD, SEM-EDS, FTIR, XPS, etc. The environmental stability of SLBJ was assessed through the toxicity characteristic leaching procedure (TCLP), Chinese standard leaching tests (CSLT), and a long-term leaching experiment (LTLE). Phase composition analysis revealed that the primary components of SLBJ are sodium jarosite and lead sulfate. TCLP and CSLT results indicated that lead content surpassed the toxicity identification standard limit by more than 47 times. Furthermore, LTLE indicated that the lead concentration surpassed the standard limit about 15 times after prolonged contact time. This study is of great significance for predicting the stability of jarosite residue and its secondary pollution to the environment.

In order to help one to judge the friction properties of lubricating oils without tests, this paper intends to establish the correlation between the characteristic parameters of lubricating oils and the friction properties. The elastohydrodynamic and boundary friction properties of poly alpha olefin (PAO) synthetic oil, polyol ester oil and paraffin-based mineral oil were tested using a Mini-Traction Machine. Fourier transform infrared microscopy is used to identify material changes before and after friction tests. The kinematic and dynamic viscosities of the three lubricating oils were measured using a petroleum product viscosity tester and a rotating rheometer. The results show that the kinematic viscosity does not directly determine the COF (coefficient of friction) of the lubricating oil, but the higher the dynamic viscosity, the higher the COF of the lubricating oil. The higher the viscosity-pressure coefficient, the lower the viscosity index (the worse the viscosity-temperature performance), and the higher the COF of the lubricating oil, which is related to the adaptability of the molecular structure of lubricating oils to pressure and temperature. PAO synthetic oils and polyol ester oils have excellent friction properties resulting from their strong adaptability to temperature and pressure variations due to the presence of linear chains and flexible groups.

The scarcity of inertial resources in the new AC–DC hybrid grids makes the grid frequency prone to fluctuation. In this paper, the relationship between the grid-side and load-side characteristics of the power router is constructed. By adjusting the port load parameters, the load power can respond quickly to the fluctuation of the grid frequency, thereby realizing rapid support of the grid frequency. Firstly, two kinds of mathematical models for sensitivity identification of load characteristics, variable voltage and variable frequency, are established to calculate the characteristic parameters of a multi-port load. The allocation rules of port power and allocation coefficients are designed according to the parameters. A frequency modulation control method that matches the load response capability of the multi-port router is proposed. Then, taking into consideration the uncertainty of load group characteristics and power, a variable coefficient frequency modulation control strategy for a multi-port power router that can adapt to the adjustable margin of loads is proposed. The proposed model is built based on a Simulink platform for validation. The simulation results show that the proposed frequency modulation strategy can be added, and the frequency modulation performance of the power grid is further improved compared to the situation without this method. The frequency is suppressed to 49.93 HZ. It is verified that this method can make the controllable load respond sensitively and effectively to grid disturbance.

In this article, a 4 × 4 miniaturized UWB-MIMO antenna with reduced isolation is designed and analyzed using a unique methodology known as characteristic mode analysis. To minimize the antenna’s physical size and to improve the isolation, an arrangement of four symmetrical radiating elements is positioned orthogonally. The antenna dimension is 40 mm × 40 mm (0.42λ0× 0.42λ0) (λ0 is the wavelength at first lower frequency), which is printed on FR-4 material with a width of 1.6 mm and εr= 4.3. A square-shaped defected ground framework was placed on the ground to improve the isolation. Etching square-shaped slots on the ground plane achieved the return losses S11 < −10 dB and isolation 26 dB in the entire operating band 3.2 GHz–12.44 GHz (UWB (3.1–10.6 GHz) and X-band (8 GHz–12 GHz) spectrum and achieved good isolation bandwidth of 118.15%. The outcomes of estimated and observed values are examined for MIMO inclusion factors such as DG, ECC, CCL, and MEG. The antenna’s performances, including radiation efficiency and gain, are remarkable for this antenna design. The designed antenna is successfully tested in a cutting-edge laboratory. The measured outcomes are quite similar to the modeled outcomes. This antenna is ideal for WLAN and Wi-Max applications.

Let f f be a meromorphic function on the complex plane with Nevanlinna characteristic T ( r , f ) T(r,f) and maximal radial characteristic ln ⁡ M ( t , f ) \ln M(t,f) , where M ( t , f ) M(t,f) is the maximum of the modulus | f | |f| on circles centered at zero and of radius t t . A number of well-known and widely used results make it possible to estimate from above the integrals of ln ⁡ M ( t , f ) \ln M (t,f) over subsets E E on segments [ 0 , r ] [0,r] in terms of T ( r , f ) T(r,f) and the linear Lebesgue measure of E E . In the paper, such estimates are obtained for the Lebesgue–Stieltjes integrals of ln ⁡ M ( t , f ) \ln M(t,f) with respect to an increasing integration function m m , and the sets E E on which the function m m is not constant can have fractal nature. At the same time, it is possible to obtain nontrivial estimates in terms of the h h -content and h h -Hausdorff measure of the set E E , as well as their partial d d -dimensional power versions with d ∈ ( 0 , 1 ] d\in (0,1] . All preceding similar estimates known to the author correspond to the extreme case of d = 1 d=1 and an absolutely continuous integration function m m with density of class L p L^p for p > 1 p>1 . The main part of the presentation is carried out immediately for the differences of subharmonic functions, or δ \delta -subharmonic functions, on circles centered at zero with explicit constants in the estimates. The only restriction in the main theorem is that the modulus of continuity of the function m m should satisfy the Dini condition at zero, and this condition, as a counterexample shows, is essential.

Background: Metamizole is one of the most used analgesic, antipyretic, and spasmolytic agents in many countries worldwide. While metamizole-induced agranulocytosis is an, albeit seldom, well-known adverse event, metamizole-associated drug-induced liver injury has been reported rarely in the literature and hence often remains unconsidered. Here, we present a unique case where metamizole-induced hepatotoxicity got unmasked by the simultaneous development of characteristic agranulocytosis. Case Report: A 22-year-old woman without known conditions presented with a new onset of fever, jaundice, and maculopapular rash and explicitly denied intake of any new substances. Laboratory tests showed liver injury, granulopenia, and positive anti-nuclear and anti-mitochondrial (AMA-M2) antibodies. Liver biopsy revealed a histological pattern characteristic of drug-induced liver injury and bone marrow biopsy, the classical picture of metamizole-induced agranulocytosis. Indeed the in-depth interview of the patient unveiled metamizole consumption over the last two months. Therefore, we could diagnose metamizole-induced hepato- and myelotoxicity. Accordingly, steroid therapy led to normalization of liver parameters and stimulation with granulocyte colony- stimulating factor to leukocyte recovery. Conclusion: This case report is intended to increase the awareness of metamizole-associated druginduced liver injury which should always be kept in mind due to its occasionally life-threatening course. Diagnosis can be difficult particularly if anamnesis and written records are without hints for prior metamizole intake.

For a discrete time multitype supercritical Galton-Watson process $(Z_n)_{n\in \mathbb{N}}$ and corresponding genealogical tree $\mathbb{T}$, we associate a new discrete time process $(Z_n^{\Phi})_{n\in\mathbb{N}}$ such that, for each $n\in \mathbb{N}$, the contribution of each individual $u\in\mathbb{T}$ to $Z_n^{\Phi}$ is determined by a (random) characteristic $\Phi$ evaluated at the age of $u$ at time $n$. In other words, $Z_n^{\Phi}$ is obtained by summing over all $u\in \mathbb{T}$ the corresponding contributions $\Phi_u$, where $(\Phi_u)_{u\in \mathbb{T}}$ are i.i.d. copies of $\Phi$. Such processes are known in the literature under the name of Crump-Mode-Jagers (CMJ) processes counted with characteristic $\Phi$. We derive a LLN and a CLT for the process $(Z_n^{\Phi})_{n\in\mathbb{N}}$ in the discrete time setting, and in particular, we show a dichotomy in its limit behavior. By applying our main result, we also obtain a generalization of the results in Kesten-Stigum [17]., Comment: a revisited version, which incorporates the referee's suggestions, and several other improvements and explanations. In particular, the section explaining how to recover the results from Kesten-Stigum [17] has been rewritten

Mutual coupling between neighboring antennas is a major concern in the array design. Using the concept of characteristic modes, this work proposes a theoretical framework for the analysis of such electromagnetic interaction and its control mechanism. The root of inter-element coupling lies in the mutually induced current in the neighboring elements. Henceforth, the initial part of this work concentrates on computing the coupled current by modeling the interaction of the uncoupled modes. Closed-form formulations have been derived for quantifying the coupling impacts. The proposed formulations have been further verified with numerical examples and method of moment based commercial solver like Antenna Toolbox. Later, the theory of substructure modes has been combined with the theory of coupled characteristic modes to understand the perturbation in coupling behavior in the presence of ground plane or a parasitic element. A design strategy has been suggested to optimize the shape of the intermediate parasitic structure for controlling the coupled current in the neighboring elements. This current based approach can find applications in different coupled scenarios like antenna arrays or in printed circuit board components.

Circumferential yielding lining is able to tolerate controlled displacements without failure, which has been proven to be an effective solution to large deformation problem in squeezing tunnels. However, up to now, there has not been a well-established design method for it. This paper aims to present a detailed analytical computation of support characteristic curve (SCC) for circumferential yielding lining, which is a significant aspect of the implementation of convergence-confinement method (CCM) in tunnel support design. Circumferential yielding lining consists of segmental shotcrete linings and highly deformable elements, and its superior performance mainly depends on the mechanical characteristic of highly deformable element. The deformation behavior of highly deformable element is firstly investigated. Its whole deforming process can be divided into three stages including elastic, yielding and compaction stages. Especially in the compaction stage of highly deformable element, a nonlinear stress–strain relationship can be observed. For mathematical convenience, the stress–strain curve in this period is processed as several linear sub-curves. Then, the reasons for closure of circumferential yielding lining in different stages are explained, and the corresponding accurate equations required for constructing the SCC are provided. Furthermore, this paper carries out two case studies illustrating the application of all equations needed to construct the SCC for circumferential yielding lining, where the reliability and feasibility of theoretical derivation are also well verified. Finally, this paper discusses the sensitivity of sub-division in element compaction stage and the influence of element length on SCC. The outcome of this paper could be used in the design of proper circumferential yielding lining.

This article explored the effect of Lactobacillus plantarum dy-1 (L. plantarum dy-1) fermentation on the basic physicochemical properties and associated in vitro antioxidant activity of barley β-glucan, including its molecular weight, monosaccharide composition, characteristic structure and rheology. Its DPPH, ABTS, hydroxyl radical scavenging capacity, and ferric reducing antioxidant potential (FRAP) were measured at different fermentation times. The results showed that the molecular weight of barley β-glucan was decreased from 1.052 × 105 Da to 4.965 × 104 Da within 0–24 h by L. plantarum dy-1 fermentation, but there was no effect on its characteristic structure. The water- and oil-holding properties of barley β-glucan were significantly enhanced with increased fermentation time, and the fluid viscous behavior of barley β-glucan was enhanced at 6% concentration, while elastic characteristics were weakened. The fermentation had no significant effect on the scavenging effect of DPPH and ABTS radicals of barley β-glucan, but the hydroxyl radical scavenging activity and total antioxidant capacity of FRAP were enhanced with increased fermentation time. Fermentation time may change the physicochemical properties and enhance antioxidant activity of barley β-glucan by reducing its molecular weight.

The analysis of Archimedean spiral slots using the theory of characteristic modes is presented in this article. Purely magnetic characteristic modes are used to study the behavior of a spiral slot etched in an infinite ground plane. The effect of the spiral geometry parameters (slot width, separation between spiral slot arms, number of spiral turns, and inner spiral spacing) on the characteristic modes are investigated using the theory of characteristic modes. Based on the results of the characteristic mode analysis, guidelines are presented for selecting the appropriate slot dimensions for realizing a compact spiral slot assembly (miniaturization), multimode behavior and for improving the bandwidth of the purely magnetic characteristic modes. Additionally, analytical equations are presented for accurately predicting the resonant frequencies of the purely magnetic characteristic mode of the spiral slot antenna.

Using biobased fuels in Diesel engines is an effective solution reduce the generation of toxic components in the exhaust gas. One of them, alcohol, is the potential fuel to reduce emissions and dependence on fossil fuels. So, this study is aimed to investigate the effects of ethanol port injection timing and delivery rate on the combustion characteristic of a heavy-duty V-12 Diesel engine when ethanol substitution percentage is 30% to reach the original diesel quantity at full load. The combustion characteristic analysis indicates that the variation in cylinder gas pressure and temperature decreases when retarded ethanol injection timing and decreased ethanol delivery rate, the engine works more smoothly due to the maximum rate of pressure rise decreases. However, the changes are greater when changing the ethanol injection timing as compared to ethanol delivery rate case.

A distinctive feature of modern Global Navigation Satellite System (GNSS) signals is that they transmit multiple signal components at the same carrier frequencies. The idea of joints across the signal channels from the same carrier frequency and even across different frequencies has been presented in many studies for tracking purposes. Carrier joint tracking is required on the premise that the frequency and phase relationship between signals are nominal values, and the bias of carrier characteristics between signals is drowned in noise as the signal reaches the ground, which requires high-gain receiving equipment to restore the original signal. The space signal-quality monitoring and evaluation system built by the National Timing Center of the Chinese Academy of Sciences is based on a 40 m dish antenna, which can automatically track a single satellite and achieve a high-fidelity reception of navigation signals to a certain extent, realizing fine signal quality monitoring (SQM) of GNSS satellites. Based on this platform, we discuss four types of time distributions of the combined signals among different signal components and provide a method to estimate the carrier characteristic bias between GNSS signals. We derived the correction method of carrier characteristic bias in the joint reception by the joint tracking mathematical model. Under the conditions of narrow correlation and unobstructed case, the carrier characteristic deviation does not vary significantly with the correlator interval and the satellite elevation angle. Based on the results of stability analysis, it is recommended that the receivers should update the carrier frequency bias correction number of the intra-frequency signal and carrier phase bias correction number of the intra-frequency signal monthly. The carrier phase deviation correction number of the inter-frequency signal is performed daily. The measured data from satellites show that the phase accumulation error of the joint tracking carrier loop can be eliminated to achieve long-term stable tracking after frequency bias correction. After the carrier phase bias correction, the joint positioning accuracy of the B2a and B2b signals was improved by 0.81%, and those of the B1C, L1C, E1C, and B2a signals were improved by 0.35%, 0.04%, 0.20%, and 0.11%, respectively. The positioning accuracy improvement effect of inter-frequency signals was greater than that of intra-frequency signals after carrier phase correction.

Shear failure of reinforced concrete (RC) beams is a form of brittle failure and has always been a concern. This study adopted the interpretable machine-learning technique to predict failure modes and identify the boundary value between different failure modes to avoid diagonal splitting failure. An experimental database consisting of 295 RC beams with or without transverse reinforcements was established. Two features were constructed to reflect the design characteristics of RC beams, namely, the shear–span ratio and the characteristic value of transverse reinforcement. The characteristic value of transverse reinforcement has two forms: (i) λsv,ft=ρstpfsv/ft, from the China design code of GB 50010-2010; and (ii) λsv,fc′=ρstpfsv/fc′0.5, from the America design code of ACI 318-19 and Canada design code of CSA A23.3-14. Six machine-learning models were developed to predict failure modes, and gradient boosting decision tree and extreme gradient boosting are recommended after comparing the prediction performance. Then, shapley additive explanations (SHAP) indicates that the characteristic value of transverse reinforcement has the most significant effect on failure mode, follow by the shear–span ratio. The characteristic value of transverse reinforcement is selected as the form of boundary value. On this basis, an accumulated local effects (ALE) plot describes how this feature affects model prediction and gives the boundary value through numerical simulation, that is, the minimum characteristic value of transverse reinforcement. Compared with the three codes, the suggested value for λsv,fc′,min has higher reliability and security for avoiding diagonal splitting failure. Accordingly, the research approach in this case is feasible and effective, and can be recommended to solve similar tasks.

The fault detection in the components of the suspension system of road vehicles is of great importance. The optimal performance of the suspension system has a big influence on the safety and stability of a vehicle. Vehicle inspection services make use of different methods of fault diagnosis of shock absorbers without the need to remove them from the vehicle. These methods generally provide an average value of the damping coefficient or a value related to the efficiency of the damper. Next, acceptance or rejection criteria are used to evaluate the condition of the damper. Consequently, there is currently no objective criterion for detecting the malfunctioning or faulty condition of shock absorbers. In this work, a novel methodology capable of obtaining the complete force–velocity characteristic curve of the shock absorber is proposed. For this purpose, the importance of using an appropriate tyre model to obtain the suspension parameters is first studied. In addition, the displacements of the sprung and unsprung masses and the excitation of the system are obtained experimentally. Next, the points that model the complete characteristic curve of a shock absorber are obtained by means of an optimization method based on evolutionary algorithms. Real tests have been conducted on a complete vehicle suspension test bench to verify the effectiveness of the proposed methodology. This work was supported in part by the Spanish Innovation Science Ministry under Grant PID2019-105572RB-I00. Funding for open access charge: Universidad de Málaga.

We introduce a new obstruction to lifting smooth proper varieties from characteristic p > 0 to characteristic 0. It is based on Grothendieck's specialization homomorphism and the resulting discrete finiteness properties of etale fundamental groups.