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The corrosion problem of the tank floor of the oil depot tank area becomes more and more serious with the extension of the operation time. At present, how to determine the potential distribution of the storage tank floor and how to judge the cathodic protection effect of the storage tank floor is the bottleneck of technological development. In this paper, by constructing a mathematical model of cathodic protection in the tank area, influence of deep well anode on potential distribution of tank bottom is calculated by boundary element method (BEM) with computer programming, to study the potential distribution of the tank floor under different anode parameters. The results show that the calculated results are in good agreement with the field measured results, which verifies the accuracy and reliability of the calculation. [ABSTRACT FROM AUTHOR]

Biofilms are ubiquitous at interfaces of natural and technical origin. Depending on type and application, biofilm formation is desired or has to be prevented. Therefore, reliable detection of initial biofilm growth is essential in many areas. One method of biofilm monitoring is the electrochemical impedance spectroscopy. Among other factors, this method is heavily dependent on the electrode geometry. In order to achieve a high measurement sensitivity, the electrode size must be chosen according to the biofilm that is to be measured. This paper presents an approach for simulating and modeling the optimal electrode geometry for a specific biofilm. First, a geometric model of a biofilm with up to 6000 individual bacteria is generated. The simulated impedances are used to calculate which electrode geometry maximizes sensitivity depending on the biofilm height. In the chosen example of an E. coli biofilm in a nutrient solution, the optimum size of an interdigital electrode (bar gap equals width) was 2.5 µm for a biofilm height of up to 2 µm. The used algorithms and models can be simply adapted for other biofilms. In this way, the most sensitive electrode geometry for a specific biofilm measurement can be determined with minimal effort. [ABSTRACT FROM AUTHOR]

Climate and land use changes re-shape the distribution of species around the world, so understanding biogeographical patterns is key to protect and manage wildlife, particularly in the case of threatened or declining species. Species with wide ranges are usually considered as common, yet the occurrence of intraspecific variability and adaptation to local conditions may pose serious challenges to their conservation. In this paper, we selected the harvest mouse Micromys minutus as a model species to assess the role of intraspecific genetic variability in shaping the environmental preferences and distribution of a widely distributed mammal across Europe. By applying an integrative approach combining species distribution modelling and phylogenetic reconstruction, we assessed the clade-specific habitat suitability of all mitochondrial clades of the species occurring in Europe, unveiling distinct bioclimatic niches. Most of Central Europe results as suitable to M. minutus, whereas different clades showed distinct distributions of suitable areas across Europe, with limited overlap. We then combined mitochondrial analyses with clade-specific suitability maps to determine the geographic delimitations of Italian and central European clades. We showed that individuals from the northernmost Italian regions actually belong to the central European clade, consistent with the biogeographical patterns of other small mammals, and indicating potential past dispersal between the Italian Peninsula and Central Europe, or human-assisted translocations. Our results highlight the importance of intraspecific variability in shaping biogeographical patterns of widely distributed species, also representing a reproducible exercise to understand their environmental preferences and eventually fostering their conservation. [ABSTRACT FROM AUTHOR]

An analytical model for junctionless double-gate FETs (JLDGFETs) in the subthreshold region is proposed in this paper. As the analytical models based on Young’s approximation demonstrate certain limitations due to the heavily doped channel of the JLDGFET, it is essential to model the electrical characteristics of a JLDGFET using alternative methods. Therefore, in this paper, by using the Fourier series and Green’s function, the potential distribution ( \phi ( {x} , {y} )) in the channel is solved, and the hot-carrier effects and random dopant fluctuation are modeled using localized trap charges and macroscopic analysis. Using the calculated \phi (x, y), {I} _{{\mathsf {DS}}} and {V} _{{\mathsf {th}}} are solved analytically with respect to various L and t {\mathsf {ox}} variations, subthreshold swing, the drain-induced barrier lowering, the localized trap charges, and a single impurity dopant. All results from the analytical model are verified through comparisons with commercially available 2-D ATLAS numerical simulation results. [ABSTRACT FROM PUBLISHER]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Climate change is very important for the distribution of plant resources, especially for crops. Angelica plants have a long history of use and significant crop resources in China, whose rhizomes are extensively used in medicine and food. In this paper, 1599 georeferenced herbarium records were analyzed using DIVA-GIS, and the ecological distribution and richness of the current and future distribution simulation were analyzed using the MaxEnt model. The results show that they are from 32 provinces in China. Among these provinces, Sichuan, Gansu, and Yunnan have the largest number of herbariums. According to the MaxEnt model simulation, it is found that the precipitation in the warmest season, annual precipitation, and the driest monthly precipitation are the foremost bioclimatic variables that control the distribution of eight selected Angelica plants (A. biserrata, A. gigas, A. laxifoliata, A. likiangensis, A. longicaudata, A. omeiensis, A. polymorpha, and A. valida). It can be seen from the potential distribution map that the suitable growth areas of A. polymorpha and A. valida have increased, while the suitable growth areas of the six species of Angelica have decreased in varying degrees, 18.24%, 20.01%, 9.91%, 53.16%, 10.06%, and 12.64% respectively. Therefore, it is necessary to protect the Angelica plants. [ABSTRACT FROM AUTHOR]

Climate change is closely related to the distribution of plant resources. Cerasus serrulata is an important plant resource in China. The study on the influence of environmental factors on the distribution of suitable areas of C. serrulata is conducive to the protection and development of C. serrulata. In this paper, the distribution information of 238 Chinese Cerasusserrulata plants was processed by DIVA-GIS. The MaxEnt model was used to simulate the current and future distribution, and the ecological distribution and richness of Cerasus were analyzed. The results showed that the Cerasus serrulata was widely distributed in Hebei, Heilongjiang, Shandong, Jiangsu, Zhejiang, Anhui, Jiangxi, Hunan, and Guizhou provinces, mainly in the low and middle elevation areas of 10 to 1200 m. Based on this model, the precipitation of the warmest quarter, the precipitation of the driest month, and the mean temperature of the coldest were the most significant bioclimatic variables affecting the distribution of C. serrulata. In the future, climate change may lead to a slight increase of 2.31% in the area of suitable habitat for Cerasus serrulata, while the optimal habitat will decrease from 20.81 to 14.55%. Therefore, conservation measures should be taken to protect these precious resources. [ABSTRACT FROM AUTHOR]

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present era, down scaling of complementary metal-oxide-semiconductor (CMOS) technology has lead the metal-oxidesemiconductor field-effect-transistor's (MOSFET) sizes to nanometer regime which in turn experiencing difficulties due to the effect of physical and technological perspective. Double-gate (DG) MOSFET is considered as a promising device to reduce the shortcoming and shrink down towards nanometer domain. This paper proposes electrostatic potential distribution and drain current models for the lightly doped symmetrical p-channel DG MOSFET. The analytic solution of potential distribution is derived by solving the 2D Poisson's equation incorporated with hole density through the superposition method. The drain current model has been explored by incorporating physical effects like threshold-voltage roll-off, channel length modulation and surface roughness scattering. Functionality of the models has been calculated in MATLAB and the obtained results are verified and compared with state of the art literature. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to present the design process, manufacturing and testing of a prototype of an axle carrier for Formula Student race car. The axle carrier is topologically optimized and additively manufactured using selective laser melting (SLM). Design/methodology/approach: The shape of the axle carrier was created in three design stages using topology optimization and four additional design stages based on finite element calculations and experimental testing. Topology optimization was performed on the basis of relevant load cases. The sixth design stage was manufactured by SLM and then tested on a loading device together with photogrammetry measurement to obtain the real deformation. Measured deformations were compared with deformation calculated by the finite element method (FEM), verified and experiences used in the last design stage. Findings: An additively manufactured axle carrier has a minimal safety factor of 1.2 according to experimental testing. The weight and maximal deformations are comparable with the milled part, although the material has about 50 per cent worse yield strength. The topologically optimized axle carrier proved big potential in the effective distribution of material and the improvement of toughness. Practical implications: This paper helps the Formula Student team to enhance the driving performance while keeping low weight. It also improves further development and upgrading of the race car. Originality/value: The whole design of the topologically optimized part was investigated – from estimation of the loads to experimental verification of FEM analysis on real part. [ABSTRACT FROM AUTHOR]

Since the insulators of transmission lines are exposed to different environmental conditions, it is important task to study insulators performance under different conditions. In this paper, silicone rubber insulators performance under different environmental conditions including rainy, icy, salt and cement are proposed and exactly is studied. Electric fields (E-fields) and voltage distributions along the insulator under various conditions have been evaluated. Moreover, the corona rings effects on insulator performance under these conditions have been presented. A 230 kV silicone rubber insulator is selected, modeled and simulated with finite element method (FEM) using the COMSOL software. The simulation is repeated for different environmental conditions and efficiency of corona ring for each scenario is evaluated. The results indicate that environmental conditions have a significant effect on the insulator performance and the corona ring somewhat alleviate the adverse effect of environmental conditions on the insulator performance. [ABSTRACT FROM AUTHOR]

In this paper, Poisson's equation is utilized to find the potential distribution inside the channel of an independent gate FinFET device by adding the effect of channel height. The channel height of the device plays an important role in surface potential calculation when top gate voltage is applied. Using surface potential, an I-V model is developed, which can find the device current both in linear and saturation regions of operation. The model is tested on devices of different dimensions and good agreement between modeled and simulated results is observed, which validates the authenticity of the proposed model. [ABSTRACT FROM AUTHOR]

With the increasing demand for electric vehicles, further development of Li+ batteries require more comprehensive studies and advanced techniques to analyze various battery material and mechanisms. Determining the concentration of Li+ and electric potential inside batteries can effectively reveal and predict the electrochemical performance, understanding the charge/discharge processes and failure mechanisms. Recently, in situ observation of Li+ movement have been reported by utilizing optical microscopy, neutron imaging (NI), neutron depth profiling (NDP), and transmission electron microscopy (TEM)-based electron energy-loss spectroscopy (EELS). These extensive works suggest their broad potential applications, including revealing the spatial distribution of Li+, mapping electrode elements, and indicating degradation mechanisms. Moreover, direct visualization of potential changes through TEM-based electron holography (EH) and Kelvin probe force microscopy (KPFM) can discover and validate more valuable information. This perspective paper summarizes the current development of advanced in situ techniques for observing Li+ and potential distribution inside batteries for the first time. Additionally, we address the key challenges faced by these techniques along with their possible solutions. The aim of this paper is to provide a comprehensive discussion of in situ methods for analyzing reaction mechanisms, optimizing electrochemical performance, and potentially supporting the further development of battery simulation.

This paper analyzes the subthreshold swing in asymmetric double gate MOSFETs with sub-20 nm channel lengths. The analysis of the carrier transport in the subthreshold region of these nano scaled MOSFET includes tunneling as an important additional mechanism to the thermionic emission. It is found that the subthreshold swing is increasing due to tunneling current and that the performance of nano scaled MOSFETs is degraded. The degradation of the subthreshold swing due to tunneling is quantified using analytical potential distribution and Wentzel-Kramers-Brillouin (WKB) approximation in this paper. This analytical approach is verified by two dimensional simulations. It is shown that the degradation of subthreshold swing increases with both reduction of channel length and increase of channel thickness. We also show that the subthreshold swing is increasing in case of different top and bottom gate oxide thicknesses. [ABSTRACT FROM AUTHOR]

With finite element method (FEM), cuboid elements (or tetrahedron elements) are often used in the traditional grounding analysis. In the irregular boundary, smaller and denser elements are usually applied to approximate the real boundary. However, this increases the number of elements in the boundary, leading to an increase in computation time. In order to introduce FEM into tunnel integrated grounding system (IGS) in high-speed railway better, a curved hexahedron element is proposed for tunnel structure. In this paper, the stiffness matrix of curved hexahedral element in space is first derived based on coordinate transformation. Two different stiffness matrices are compared in the condition that the structure of curved hexahedron element is highly similar to that of cuboid element. Later, the number of required elements according to the proposed method is compared with that of the traditional one on the basis of meeting same accuracy requirement. Finally, the results of the proposed method are compared with those of current distribution, electromagnetic fields, grounding and soil structure analysis (CDEGS). Through the above-mentioned three comparison schemes, the curved hexahedron element model is verified by its precision and applicability. From this, the distribution of the electromagnetic field inside the tunnel IGS is obtained. [ABSTRACT FROM AUTHOR]

In this paper, an analytical calculation of the magnetic field in a consequent-pole bearingless permanent magnet (PM) type motor with rotor eccentricity is proposed. The analytical method is based on the resolution of Laplace's and Poisson's equations. Due to the presence of consequent-pole, the general solution of the first-order for the vector potential distribution in the air-gap is presented considering the first harmonic. Here, the magnetic field distributions by the analytical method are compared with those obtained from finite element (FE) analyses. Then, the corresponding performances are quantitatively assessed by the finite-element method. [ABSTRACT FROM AUTHOR]

In the strong axial (guide) magnetic field and uniform beam density approximations, we calculate scalar potential distribution induced by axisymmetric annular relativistic charged-particle beam in a finite-length coaxial drift tube. This scalar potential distribution allows us to find an approximate radial position at which the extremum of the scalar potential is attained in the coaxial drift tube inside the annular relativistic charged-particle beam. By knowing the approximate extremal radial position, we obtain the analytical estimate for the space-charge limited (SCL) current of axisymmetric annular (finite thickness) relativistic charged-particle beam propagating in strong axial magnetic field in a finite length coaxial drift tube and establish a simple correspondence of this result to that in a long coaxial drift tube. A comparison of numerical nonlinear calculations and the analytical estimate for the SCL current in the finite-length coaxial drift tube is also given. [ABSTRACT FROM AUTHOR]

This paper presents the results of dynamic behavior modeling of phase states (solid and liquid) of water clusters ((H2O)8, (H2O)10, and (H2O)12) by molecular dynamics method. The initial configurations of the clusters were cube for octamer, pentagonal prism for decamer, and fused-cube structure for dodecamer. The different analytical interaction potentials (TIPnP (n = 3, 4), SPC, and SPC/E) were applied to the phase dynamics of water octamer to choose the most appropriate potential for the study. The dynamic criteria based on the molecule's potential energy distribution were applied for identification of solid and liquid phases of decamer and dodecamer. The most probable conformers of decamer and dodecamer in different phases were obtained. [ABSTRACT FROM AUTHOR]

This paper presents experimental results of the surface charges and charge decay measurement on the surface of polymeric insulator. In this research, the effect of surface charges on electric field and potential distribution has been investigated. Therefore, using measured electric charge and charge decay, the electric field and surface potential on insulator are studied by computer simulations. The accumulation of electric charge under DC electric field makes a significant difference compared to AC electric field, and this increases the rate of electrical failure and corrosion in HVDC insulators. So, a thorough understanding of the surface charge effect on insulation performance is necessary under various stresses. The experimental results revealed that the amount of charges increases linearly with the rising corona voltage and the charging time for both polarities. It was also observed that the amount of surface charges deposited by positive corona charging is less than negative corona charging. The simulation results illustrate that surface charges are important in potential and electric field variations. [ABSTRACT FROM AUTHOR]

The future compact linear collider (CLIC) offers a possibility for a rich precision physics programme, in particular in the Higgs sector through the energy staging. This is the first paper addressing the measurement of the standard model Higgs boson decay into two muons at 1.4 TeV CLIC. With respect to similar studies at future linear colliders, this paper includes several novel contributions to the statistical uncertainty of the measurement. The latter includes the equivalent photon approximation employed to describe $$e^+e^-$$ and $$e\gamma $$ interactions whenever the virtuality of the mediated photon is smaller than 4 GeV and realistic forward electron tagging based on energy deposition maps in the forward calorimeters, as well as several processes with the Beamstrahlung photons that results in irreducible contribution to the signal. In addition, coincidence of the Bhabha scattering with the signal and background processes is considered, altering the signal selection efficiency. The study is performed using a fully simulated CLIC_ILD detector model. It is shown that the branching ratio for the Higgs decay into a pair of muons BR( $${H\rightarrow \mu ^+\mu ^-}$$ ) times the Higgs production cross-section in WW-fusion $$\sigma (H\nu \bar{\nu })$$ can be measured with 38 % statistical accuracy at $${\sqrt{s} =\text {1.4 TeV}}$$ , assuming an integrated luminosity of 1.5 ab $$^{-1}$$ with unpolarised beams. If 80 % electron beam polarisation is considered, the statistical uncertainty of the measurement is reduced to 25 %. Systematic uncertainties are negligible in comparison to the statistical uncertainty. [ABSTRACT FROM AUTHOR]

Electromagnetic flow meters are a gold standard in measuring the mean flow velocity of conductive liquids and slurries in process industry. A drawback of this approach is that the velocity field cannot be determined. Velocity field information is important for characterizing multiphase flows in the process industry. Recently, electromagnetic flow tomography has been proposed for estimating velocity fields in process pipes. The modality uses multiple magnetic field excitations produced by coils and a set of electrodes attached to the inner surface of the pipe to measure the induced voltages. In earlier studies, a method for reconstructing 2-D velocity field on a pipe cross section has been developed. The method utilizes a finite-element-based computational forward model for computing boundary voltages and a Bayesian framework for inverse problem to reconstruct the velocity field. Magnetic field excitations affect the boundary voltage measurements and, hence, the reconstructed velocity field. Optimization of excitations is especially important when imaging axisymmetric flows, since all axisymmetric velocity fields having the same mean velocity produce the same boundary voltage data when uniform magnetic field excitations are used. In this paper, two methods for optimizing coil currents and resulting magnetic fields are proposed. The methods are based on maximizing the norm of the boundary voltage measurements or minimizing the uncertainty in the reconstructed velocity field estimates. The results show that by optimizing coil currents it is possible to obtain accurate velocity field estimates using just one or two optimal excitations. [ABSTRACT FROM PUBLISHER]

The paper presents a fast technique to identify the components of specific conductivity tensor of thin semiconductor planes. The proposed technique is based on a well-known method with a linear location of a four-probe tester. It is scientifically backed up by solving the relevant boundary problems of electrodynamics and characterized by the simplicity of measurements and calculations. Moreover, the suggested method does not require the use of complicated equipment and also the boundary conditions have been taken into account. Experimental testing has been carried out on monocrystals of diarsenide of cadmium and diarsenide of zinc. Practical recommendations are given on how to make the necessary measurements more precise. [ABSTRACT FROM AUTHOR]

As the basic conception of the Grey system theory, grey number is a kind of number with known range but unknown exact value because of lack of information. Because the condition of poor information is so popular and personal limited rationality is obvious, in a sense, grey number is an important means of compliance with the patterns of human judgment. In this study, based on the way of human thinking and decision-making, the method of grey number is used to describe the character in decision making. The study focuses on the grey potential degree and its application on rapid grey decision model. The main contents and innovations of this paper are as follows. The background of grey evaluation by grey potential is briefly introduced; the typical ways of evaluation are summarized and compared. The advantages on time-saving, high experts' satisfaction, full information keeping, and use of grey evaluation are presented. Grey number whitening and point accuracy are discussed and analyzed. The conception of grey relative potential degree is built based on the features of grey number. The application model of grey potential in rapid grey evaluation is researched. Based on the implication of grey superiority potential and grey inferior potential, relationship of grey numbers is discussed and grey evaluation levels are obtained to make evaluation. Case studies show that grey potential models are reasonable and effective. Furthermore the results show that core of grey potential degree has certain theoretical significance and good practical value. [ABSTRACT FROM AUTHOR]

Copyright of Electrotechnical Review / Elektrotehniski Vestnik is the property of Electrotechnical Society of Slovenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper discusses the numerical evaluation of the hydrodynamic characteristics of submerged and surface piercing moving bodies. Generally, two main classes of potential methods are used for hydrodynamic characteristic analysis of steady moving bodies which are Rankine and Kelvin-Havelock singularity distribution. In this paper, the Kelvin- Havelock sources are used for simulating the moving bodies and then free surface wave patterns are obtained. Numerical evaluation of potential distribution of a Kelvin-Havelock source is completely presented and discussed. Numerical results are calculated and presented for a 2D cylinder, single source, two parallel moving source, sphere, ellipsoid and standard Wigley hull in different situation that show acceptable agreement with results of other literatures or experiments. [ABSTRACT FROM AUTHOR]

The erosion of the stress grading system of converter-fed rotating machines may occur by partial discharges and heat generation. There remain unclear issues in the formation of the potential and temperature distributions along the stress grading system of coils. In this paper, the potential distributions on the stress grading system of the model coil bar are measured under the application of 1 kHz square wave voltages of 10 kV in peak to peak value with/without 5 kV DC biased voltage. It turns out that DC bias voltage has little effect on potential distribution on a coil surface. [ABSTRACT FROM AUTHOR]

With the deepening and expansion of semiconductor technology and research, in order to continuously optimize the structure and performance of semiconductor detectors, a high-precision hexagonal spiral silicon drift detector (SDD) is proposed in this paper. In order to obtain a more accurate spiral ring structure, this paper goes beyond the first-order formula in the Taylor expansion for calculating the radius of the spiral ring. Based on the first-order formula, the second-order formula for calculating the radius of the spiral ring is further developed and derived. The point coordinates are obtained by combining the radius, angle, and ring spacing change formula to obtain a more accurate spiral ring structure. The actual number of turns is more accurate than that obtained from first-order approximation, which better solves the problem of accurate calculation of the number of spiral rings and the structure of the spiral SDD in the existing technology, that is, the accurate calculation of the radius of the spiral ring. In order to verify the abovementioned theory, we model this new structure and use Technology Computer-Aided Design to system simulate and study its electrical properties, including potential distribution, electric field distribution, and electron concentration distribution. According to the simulation results, compared with the first-order formula, the second-order formula has better electrical properties; more uniform distribution of potential, electric field, and electron concentration; and a clearer electron drift channel.

The bridge of the interior permanent magnet (IPM) machine can reduce the leakage of the machine, which makes the utilization rate of the permanent magnet (PM) improved. However, the asymmetric saturation in the bridges will cause the asymmetry distribution of the magnetic potential on the rotor surface, which will bring challenges to the accurate calculation of inductances. Excited by the armature current at different initial phase angles, the flux distributions in the bridges are analyzed. Meanwhile, the reason why the asymmetric saturation exists in the bridges is revealed theoretically. Based on the above analysis, the rotor magnetic potential (RMP) model for an IPM machine with the bridges is established and used to calculate the armature reaction magnetic field and inductances of the IPM machine. In this paper, the RMP distribution in the bridges is obtained by considering asymmetric saturation, so the RMP model can reflect the rotor surface magnetic potential distribution more accurately, which is evident from the adjacent degree between the calculation results and the finite-element analysis (FEA) ones. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Sociedad Entomológica Argentina is the property of Sociedad Entomologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bactrocera correcta (Bezzi, 1916), commonly known as the guava fruit fly, is of concern as an invasive pest in tropical and subtropical countries. It was first recorded in China in 1982 in Yuanjiang, in southern Yunnan Province. We monitored the spread of B. correcta in the field during 2017 and 2018, and found that it had moved about 300 kilometers eastward from its known range in 2011 in Yunnan and has now entered the neighboring Guangxi Province. A species distribution model used to predict the potential distribution of B. correcta in China revealed that southern China provides the most suitable habitat for B. correcta, and that further eastward expansion threatens large areas of southeastern China. Results from this study suggest that the rapid eastward migration of B. correcta is related to improved highway and high-speed railway systems in China that transport fruits and vegetables to eastern markets. This paper also discusses methods to slow the expansion of B. correcta in China. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of the electrochemical and semiconductor properties of magnetite on a semiconductor/electrolyte interface. It is shown that the solid phase of the oxide has a bulk zone that leads to charge and potential distributions in both the bulk phase and electrolyte solution. The presence of a bulk zone on the magnetite surface is evidenced by the observed linear behavior of 1/C2 as a function of E (where C is capacitance and E is potential). [ABSTRACT FROM AUTHOR]

Rhododendron delavayi Franch. predominantly thrives in broad-leaved evergreen forests and bushes at altitudes of 1,200–3,200 meters. It favors a cool, moist climate and thrives in acidic soils. Due to its high ornamental, medicinal, and scientific values, understanding its ecological needs and optimal cultivation ranges is crucial. This study analyzing the key environmental factors and their thresholds affecting its distribution and predicts the future potential habitats of R. delavayi using existing distribution data alongside current and projected climate data. The results indicate that the primary environmental influencers are soil pH (4.9–5.4), precipitation in the driest month (10–20 mm), and altitude, contributing 41.8, 24.1, and 18.3%, respectively. It also shows a declining trend in suitable habitats: from 27.75 × 104 km² under current conditions, to 3.69 × 104 km² by the 2050s, and further to 2.65 × 104 km² by the 2070s. [ABSTRACT FROM AUTHOR]

In recent years, the continuous expansion of Spartina alterniflora (S. alterniflora) has caused serious damage to coastal wetland ecosystem. Mapping the coverage of S. alterniflora by remote sensing and analyzing its growth pattern pose great importance in controlling the expansion and maintaining the biodiversity of coastal wetlands in Guangxi. This study aimed to use harmonic regression to fit time series data of vegetation indices based on Landsat images, and the phenological features were extracted as the input of random forest model to distinguish S. alterniflora in coastal zone of Guangxi from 2009 to 2020. The influence of natural environmental factors on the distribution of S. alterniflora was evaluated by Maxent model, and the potential distribution was analyzed. The results showed that: (1) Based on the time series data of characteristic indices fitted by harmonic regression, the extraction of phenological features of S. alterniflora identification effect exhibited high accuracy (in the result of 2009, Overall Accuracy [OA] = 97.33%, Kappa = 0.95). (2) During 2009–2020, the S. alterniflora in coastal zone of Guangxi kept proliferating and expanding from east to west. The total area of S. alterniflora continued to increase while the growth rate showed a trend that increased first and then decreased. (3) The Maxent model shows good accuracy in simulating the habitat of S. alterniflora, with a potential distribution area of 14,303.39 hm2. The findings will be beneficial to the understanding of dynamic changes of S. alterniflora in coastal zone of Guangxi and provide a scientific reference for other coastal wetland studies on S. alterniflora expansion. [ABSTRACT FROM AUTHOR]

Simple Summary: Bactrocera tsuneonis (Miyake) is a significant pest of commercial citrus crops. It is a univoltine and oligophagous species widely distributed in Japan and China. In this study, the potential distribution of the B. tsuneonis population under current and different future climate change scenarios was modeled using MaxEnt software (v. 3.4.1) and optimized using R software (v. 4.3.2). Under current climate conditions, the potentially suitable areas were mainly concentrated in Central, South, and East China. The total area of habitats suitable for this pest was predicted to increase in the future climate scenarios. The centroid of the total suitable habitat for this pest gradually shifted westward and northward. Our findings provide new insights that could aid the monitoring of B. tsuneonis in China. The invasive pest, Bactrocera tsuneonis (Miyake), has become a significant threat to China's citrus industry. Predicting the area of potentially suitable habitats for B. tsuneonis is essential for optimizing pest control strategies that mitigate its impact on the citrus industry. Here, existing distribution data for B. tsuneonis, as well as current climate data and projections for four future periods (2021–2040, 2041–2060, 2061–2080, and 2081–2100) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) were obtained. The distribution of B. tsuneonis under current and different climate change scenarios in China was predicted using the optimized MaxEnt model, ArcGIS, and the ENMeval data package. Model accuracy was assessed using ROC curves, and the primary environmental factors influencing the distribution of the pest were identified based on the percent contribution. When the regularization multiplier (RM) was set to 1.5 and the feature combination (FC) was set to LQH, a model with lower complexity was obtained. Under these parameter settings, the mean training AUC was 0.9916, and the mean testing AUC was 0.9854, indicating high predictive performance. The most influential environmental variables limiting the distribution of B. tsuneonis were the Precipitation of Warmest Quarter (Bio18) and Temperature Seasonality (standard deviation ×100) (Bio4). Under current climatic conditions, potentially suitable habitat for B. tsuneonis in China covered an area of 215.9 × 104 km2, accounting for 22.49% of the country's land area. Potentially suitable habitat was primarily concentrated in Central China, South China, and East China. However, under future climatic projections, the area of suitable habitat for B. tsuneonis exhibited varying degrees of expansion. Furthermore, the centroid of the total suitable habitat for this pest gradually shifted westward and northward. These findings suggest that B. tsuneonis will spread to northern and western regions of China under future climate changes. The results of our study indicate that climate change will have a major effect on the invasion of B. tsuneonis and have implications for the development of strategies to control the spread of B. tsuneonis in China. [ABSTRACT FROM AUTHOR]

Exploring the geographical distribution of forestry pests is crucial for formulating pest management strategies. Cyrtotrachelus buqueti (Guer) stands out as one of the primary pests among China's forestry hazards. This study employs the MaxEnt model, along with 19 bioclimatic variables and habitat characteristics, to predict the current and future distribution of C. buqueti under three typical emission scenarios for 2050 and 2070 (2.6 W/m2 (SSP1-2.6), 7.0 W/m2 (SSP3-7.0), and 8.5 W/m2 (SSP5-8.5)). Among the 19 bioclimatic variables, BIO 14 (precipitation of the driest month), BIO 8 (mean temperature of the wettest quarter), Elev, slope, and aspect were identified as significant contributors. These five variables are critical environmental factors affecting the suitability of habitats for C. buqueti and are representative of its potential habitat. The results indicate that C. buqueti predominantly inhabits southern regions such as Chongqing, Guizhou, Yunnan, Sichuan, Guangxi, Shaanxi, Hubei, Hainan, and Taiwan. Among them, Chongqing, Guizhou, and Yunnan are the primary distribution areas of high suitability. In the future, the centroid's movement direction will generally shift southward, with an expansion trend observed in the distribution areas of each province. This study enhances researchers' understanding of forestry pest dynamics and promotes proactive management strategies to mitigate their impact on forest ecosystems and agricultural productivity. [ABSTRACT FROM AUTHOR]

In this paper two probability distributions are analyzed which are formed by compounding inverse Weibull with zero-truncated Poisson and geometric distributions. The distributions can be used to model lifetime of series system where the lifetimes follow inverse Weibull distribution and the subgroup size being random follows either geometric or zero-truncated Poisson distribution. Some of the important statistical and reliability properties of each of the distributions are derived. The distributions are found to exhibit both monotone and non-monotone failure rates. The parameters of the distributions are estimated using the expectation-maximization algorithm and the method of minimum distance estimation. The potentials of the distributions are explored through three real life data sets and are compared with similar compounded distributions, viz. Weibull-geometric, Weibull-Poisson, exponential-geometric and exponential-Poisson distributions. [ABSTRACT FROM AUTHOR]

Abstract Shale oil refers to oil stored in organic-rich shale. It is an important part of unconventional oil and provides a large amount of resources. Based on the systematic study of the geological characteristics of shale oil in China's major continental basins, the geological connotation of the "sweet area (section)" in shale oil is proposed in this paper, and it refers to areas (sections) that can be preferentially explored and developed in oil-bearing shale formations under current economic and technical conditions. The formation conditions and distribution characteristics of continental shale oil in China are analyzed with a focus on the geological properties of the Triassic Yanchang Formation in the Ordos Basin, the Cretaceous Qingshankou Formation in the Songliao Basin and the Permian Lucaogou Formation of the Jimusar Sag in the Junggar Basin. It is found that the "sweet areas" of shale oil with medium-high maturation are mainly located in thick shales with a Ro greater than 0.9%, and the "sweet sections" are mainly located in the middle and lower parts of the shale formation. The geological resources of continental shale oil in the major continental basins in China are estimated to be approximately 3700 × 108 tons. The in situ conversion process (ICP) may be a key technology for the effective development of medium-to low-mature shale oil. The scale, maximum burial depth and present depth of the organic-rich shale are proposed as the three key parameters for the optimization of pilot sites by taking the Triassic Yanchang Formation in the Ordos Basin as an example. Using ICP, it is expected that the recoverable resources of China's continental shale oil will be approximately (400–500) × 108 tons. The terminology of "man-made reservoir" is proposed in this paper. In an "man-made reservoir", the overall industrial output of the "sweet areas (sections)" is formed by artificial intervention and the construction of an underground fracture network system with "man-made permeability". Continental shale oil may be another revolutionary source of unconventional oil and is expected to be first successfully produced in China. Highlights • The "sweet areas(sections)" of continental shale oil with medium-high maturation are illustrated with examples and the resources are assessed. • The formation conditions and distribution characteristics of continental shale oil in China are analyzed. • Some important concepts are proposed, including "exploring oil into source kitchen", "source rock oil", "man-made oil reservoir", etc. [ABSTRACT FROM AUTHOR]

In this paper, we investigated a set of narrow endemics of Centaurea subsect. Phalolepis from the mountains of South Italy (mainly Calabria and Salento), segregated from the widespread species Centaurea deusta, using microsatellite (SSR) markers. The goal was to analyse the genetic makeup (levels and structure) of C. deusta and the segregated species and verify whether genetic clusters were in agreement with current classification of the species. With C. deusta, we also carried out an ecological niche modelling (ENM) analysis to check its potential distribution under present climatic conditions and to project it to the Last Glacial Maximum (LGM). As also found in former studies with subsect. Phalolepis in Greece and Turkey using the same set of SSRs, genetic diversity for the segregated Italian species was higher than expected for narrow endemics with small populations. Genetic clusters, however, were not correlated with the described species and did not support the segregation of the purported narrow endemics from a widely defined C. deusta. The results of the ENM indicate that the Adriatic Sea was a migration corridor for C. deusta at the LGM. [ABSTRACT FROM AUTHOR]

A threshold voltage model based on the solution of the three-dimensional (3-D) Poisson's equation for an undoped triple-gate (TG) fin-shaped field-effect transistor (FinFET) with localized interface trapped charge is presented in this paper. Such localized interface charge created by either hot carrier injection or bias temperature instability degrades the threshold voltage and thereby the overall performance of FinFET devices. The proposed model considers the location of the interface traps and the length of the damaged region. The potential distribution and the threshold voltage of the TG FinFET obtained from the model are compared with data from technology computer-aided design simulations, which validates the model for different device dimensions, interface trapped charge densities, damaged region lengths, and drain biases. The results show that the variation of the threshold voltage mainly depends on the length of the damaged region and the thickness of the oxide but is independent of the fin width and height. Furthermore, short-channel effects such as threshold voltage roll-off and drain-induced barrier lowering are investigated, considering both positive and negative interface traps. [ABSTRACT FROM AUTHOR]

Highlight • Under DC voltage, surface charge indicates polarity effect. • Increasing the voltage amplitudes led to an increase of the surface charge density. • Corona voltage and the charging time for both polarities rise, the amount of charges increases linearly. • Relationship between amount of surface charges and number of photons have been carried out using corona camera. Abstract The objective of the present study is to investigate the surface charge measurement on the surface of polymeric insulator under AC and DC voltages experimentally. According to the test results, increasing the voltage amplitudes led to an increase of the surface charge density, the voltage application duration was also extended. During the tests, it was observed that as the corona voltage and the charging time for both polarities rise, the amount of charges increases linearly. The results show that more surface charge was deposited by negative corona charging when compared with positive corona charging. Also in this paper, the effect of the corona variations on the amount of surface charge have been investigated. For this purpose, relationship between amount of surface charges and number of photons have been carried out using corona camera. Moreover, attempt was made to investigate the effects of surface charges on potential and electric field distribution along polymeric insulator under AC and DC voltages using computer simulations based on finite element method (FEM). The present paper was conducted to study the effects of magnitude, polarity, and location of surface charges on surface potential distribution along the insulator. [ABSTRACT FROM AUTHOR]

Asymmetric surface dielectric barrier discharge (SDBD) plasma actuators have been intensely studied for a number of years due to their potential applications for aerodynamic control. In this paper, four types of actuators with different configurations of exposed electrode are proposed. The SDBD actuators investigated are driven by dual-power supply, referred to as a fixed AC high voltage and an adjustable DC bias. The effects of the electrode structures on the dielectric surface potential distribution, the electric wind velocity, and the mean thrust production are studied, and the dominative factors of airflow acceleration behavior are revealed. The results have shown that the actions of the SDBD actuator are mainly dependent on the geometry of the exposed electrode. Besides, the surface potential distribution can effectively affect the airflow acceleration behavior. With the application of an appropriate additional DC bias, the surface potential will be modified. As a result, the performance of the electric wind produced by a single SDBD can be significantly improved. In addition, the work also illustrates that the actuators with more negative surface potential present better mechanical performance. [ABSTRACT FROM AUTHOR]

In this paper, a pest control model with state-dependent impulses is firstly established, which relies on releasing of natural enemies, together with spraying pesticides. By using the successor function of differential equation geometry rules, the existence of order one periodic solution is discussed. According to the Analogue of Poincaré's Criterion, the orbitally asymptotic stability of the order one periodic solution is obtained. Furthermore, we investigated the global attractor of the system. From a biological point of view, our results indicate that: (1) the pest population can be controlled below some threshold; (2) compared to single measure, it is more efficient to take two measures for reducing the level of the pests. [ABSTRACT FROM AUTHOR]

We consider a two-stage distribution system, where the first stage consists of potential distribution centres (DCs) and the second stage consists of geographically dispersed existing retailers. Our goal is to determine the set of open DCs and assignment of open DCs to retailers simultaneously with inventory decisions of retailers. In addition to the DC-specific fixed facility location costs, we explicitly model the inventory replenishment and holding costs at the retailers and truckload transportation costs between the DCs and the retailers. The transportation costs are subject to truck/cargo capacity, leading to an integrated location-inventory problem with explicit cargo costs. We develop a mixed-integer nonlinear model and analyse its structural properties leading to exact expressions for the so-called implied facility assignment costs and imputed per-unit per-mile transportation costs. These expressions analytically demonstrate the interplay between strategic location and tactical inventory/transportation decisions in terms of resulting operational costs. Although both the theory and practice of integrated logistics have recognized the fact that strategic and tactical decisions are interrelated, to the best of our knowledge, our paper is the first to offer closed-form results demonstrating the relationship explicitly. We propose an efficient solution approach utilizing the implied facility assignment costs and we demonstrate that significant savings are realizable when the inventory decisions and cargo costs are modelled explicitly for facility location purposes. [ABSTRACT FROM AUTHOR]