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In this paper, an electro-hydraulic exciter controlled by an alternating current distribution valve is proposed, and a systematic analysis of the influence of pipe effect on the vibration characteristics of the electro-hydraulic exciter is investigated by simulation and experiments. The vibration characteristics curves for different pipe parameters are obtained, and the relative errors between simulation and experiment are evaluated. Moreover, a significant regression model of pipe parameters and vibration characteristics of the electro-hydraulic exciter is established by using the quadratic regression analysis method and the Box-Behnken experiment design method. Significant differences in the influence of pipe parameters on vibration characteristics are obtained by ANOVA (Analysis of Variance), and the influence of pipe parameter interaction on vibration characteristics is discussed. The results show that the relative importance of pipe parameters on the vibration characteristics of electro-hydraulic exciter, from high to low, is as follows: pipe diameter, elastic modulus, and pipe length. Notably, there is also an interaction between the pipe parameters, and the significance of these interactions is ranked from high to low as the interaction between the layers of steel wire and diameter, the interaction between diameter and length, and the interaction between the layers of steel wire and length. [ABSTRACT FROM AUTHOR]

A dc voltage restorer (dc‐VR) with optimal droop control is developed to reduce the power loss and solve the dynamic current imbalance simultaneously of the zonal dc distribution system integrating multi‐parallel energy storage. Firstly, the power loss model composed of line loss and converter loss is built and it is proved to be a strictly convex function with respect to droop coefficients, which indicates the power loss can be mitigated by optimizing the current distribution. Thus, an image‐based droop optimization method is proposed to search for the optimal droop coefficients. Then, the economy of voltage compensation on power loss reduction is investigated and an ESS‐combined dc‐VR is designed, including an interleaved parallel architecture and a capacitor‐integrated electric spring (C‐ES). Unified virtual inertia is proposed for interleaved parallel bridge arms to make their dynamic performance consistent. And the newly introduced C‐ES can keep the bus voltage at the rated level to reduce the system cost. Therefore, the problem of dynamic currents imbalance is addressed from the points of converter structure (dc‐VR) and control system (unified inertia), and the power loss can be reduced by voltage recovery (C‐ES) and optimizing the current reallocation which is achieved by updating sharing coefficients from the image‐based droop optimization method. Finally, the simulation cases validate the effectiveness of the proposed optimal‐droop dc‐VR on dynamic current balance and power loss reduction, and hardware in the loop experiment results prove the consistent dynamic characteristics of the dc‐VR's arms. [ABSTRACT FROM AUTHOR]

Transparent heaters are gaining significant attention for applications such as antifog glass, smart windows, and smart farm greenhouses. A transparent heater basically consists of transparent conducting materials that serve as a heating area and contact pad electrode to apply power. To fabricate a transparent heater, materials with excellent light transmittance and low sheet resistance are required. Among various transparent conducting materials, such as Indium Tin Oxide (ITO), carbon nanotube (CNT), graphene, and silver nanowires (AgNWs), AgNWs are particularly favored due to their good electrical, optical, and mechanical properties. However, in order to improve the heating characteristics of transparent heaters, research is essential not only on improving the properties of transparent conducting materials but also on the design of contact pad electrodes that can uniformly improve current distribution. Here, we explore various shapes of contact pad electrodes for AgNW-based transparent heaters to improve current distribution. Shapes such as line, spot, twisted, and parallel-type contact pad electrodes are designed and investigated to optimize overall heating characteristics. We analyze the heating properties of these transparent heaters with various contact pad electrodes, demonstrating how their specific shape and size affect heating characteristics and uniformity. We also investigate the optimal shape of the contact pad electrode to minimize transmission loss through UV-VIS spectroscopy. As a result, we confirm that the shape of the contact pad electrode was important for simultaneously achieving high heating characteristics of 120 °C, good heating uniformity, and over 80% transparency in an AgNW-based transparent heater. [ABSTRACT FROM AUTHOR]

A low-noise amplifier (LNA) is one of the most crucial components of a communication system. The current low-noise amplifier design faces challenges due to intrinsic noise sources in CMOS transistors and trade-offs to maximize gain and bandwidth. Hence the Optimal design of a low-power ultra-wideband low-noise transconductance amplifier in 0.18 µm CMOS is introduced to minimize the noise figure of the amplifier. Ultra wideband (UWB) signals cover a wide frequency range making it challenging to achieve good input and output matching across the entire band. Thus, Cascode inductive degenerative using pi matching network enhances input–output matching by providing impedance transformation, matching source impedance to low input impedance, and improving power transfer rate. However, the cascode configuration with pi matching offers superior performance over a wide frequency range, but it requires careful consideration of gain and noise figures. Therefore, a current reuse technique is utilized to improve gain and reduce noise figures by optimizing the distribution of bias currents and enhancing the overall performance of the amplifier. Furthermore, the main design challenge for LNAs is achieving high linearity in interference-filled environments. Hence novel Cascade inductive degenerative using T matching network addresses low-frequency signal interference by utilizing multiple amplifier stages for gain and high linearity. Thus, the result obtained showed that the proposed model outperforms the existing design with high gain of 17.7 dB, high input return loss of 10.6 dB, high FOM of 24.4 and low noise figures of 0.573 dB, thus improves the overall performance of the system. [ABSTRACT FROM AUTHOR]

The current distribution network is developing toward the direction of information and intelligent distribution Internet of Things (IoT). In order to explore the online monitoring system for transient electromechanical simulation of distribution networks, this paper is based on the equivalent model of generator sets. Firstly, it describes the relevant theoretical knowledge of edge computing, designs the distribution IoT based on edge computing, and briefly introduces its network architecture. Secondly, based on the discrete-time domain equivalent model of generators, the electromechanical transient simulation distribution network is constructed by introducing the machine network division of the power network. Finally, the Western System Coordinating Council (WSCC)-3 units and 9 nodes are taken as an example, and simulation experiments are conducted under two fault simulation conditions to verify the effectiveness of the simulation model. The results show that under the two fault simulation conditions, the results of equivalent model simulation of generator terminal voltage and relative power angle change are like those of the Power System Analysis Software Package (PSASP). The changing trend of the two is similar and stable. After the PSASP results are stabilized at a value, the simulation results fluctuate extremely up and down the value. For example, under fault condition 1, the changing trend of the relative power angle of the No. 2 generator is first fluctuating and then becomes stable. After violent fluctuation, the relative power angle tends to be stable from about 20s to -12.35°. The result of PSASP software is stable at -12.35°. The transient electromechanical simulation of the generator equivalent model can provide some ideas for the online monitoring system of the distribution network. [ABSTRACT FROM AUTHOR]

With the high penetration and flexible access of inverter‐interfaced distributed generators (IIDGs), it is gradually becoming difficult for traditional protection schemes to meet the requirements for the safe operation of distribution networks (DNs). Active protection schemes based on power electronic equipment provide a new approach. On the basis of the controllability of voltage source converters, a method for active high‐frequency signal injection and a selection principle for the corresponding control parameters are proposed. Considering the impact of T‐connected load branches on the protected line, the high‐frequency current characteristics at the three terminals during internal and external faults are analysed. On this basis, an active protection scheme based on high‐frequency current is proposed for DNs with IIDGs. The performance of the proposed scheme is verified via PSCAD/EMTDC simulation software. The test results show that the proposed scheme can reliably trip during internal faults and identify faulty phases, which has better endurance to fault resistance. [ABSTRACT FROM AUTHOR]

The coffee sector in Ethiopia is the livelihood of more than 20% of the population and accounts more than 25% of the country's foreign exchange earnings. Climate change is expected to affect the climatic suitability of coffee in Ethiopia, and this would have implications for global coffee output, the national economy, and farmers' livelihoods in Ethiopia. The objective of this paper is to assess the current and future impacts of climate change on bioclimatic suitability to C.arbica production in Ethiopia. Based on the current distribution of coffee production areas and climate change predictions from HadGEM2 and CCSM2 models and using the Maximum Entropy (MaxEnt) bioclimatic modeling approach, future changes in climatic suitability for C. arabica were predicted. Coffee production sites in Ethiopia were geo-referenced and used as input in the MAXENT model. The findings indicated that climate change will increase the suitable growing area for coffee by about 44.2% and 30.37% under HadGEM2 and CCSM2 models, respectively, by 2080 in Ethiopia. The study also revealed a westward and northwestward shift in the climatic suitability to C. arabica production in Ethiopia. This indicates that the suitability of some areas will continue with some adaptation practice, whilst others currently suitable will be unsuitable, yet others that are unsuitable will be suitable for arabica coffee production. These findings are intended to support stakeholders in the coffee sector in developing strategies for reducing the vulnerability of coffee production to climate change. Site-specific strategies should be developed to build a more climate resilient coffee livelihood in the changing climate. [ABSTRACT FROM AUTHOR]

Rubus idaeus is a pivotal cultivated species of raspberry known for its attractive color, distinct flavor, and numerous health benefits. It can be used in pharmaceutical, cosmetics, agriculture and food industries not only as fresh but also as a processed product. Nowadays due to climatic changes, genetic diversity of cultivars has decreased dramatically. However, until now, the status of wild R. idaeus resources in China have not been exploited. In this study, we investigated the resources of wild R. idaeus in China to secure its future potential and sustainability. The MaxEnt model was used to predict R. idaeus suitable habitats and spatial distribution patterns for current and future climate scenarios, based on wild domestic geographic distribution data, current and future climate variables, and topographic variables. The results showed that, mean temperature of the coldest quarter (bio11), precipitation of the coldest quarter (bio19), precipitation of the warmest quarter (bio18), and temperature seasonality (bio4) were crucial factors affecting the distribution of R. idaeus. Presently, the suitable habitats were mainly distributed in the north of China including Xinjiang, Inner Mongolia, Gansu, Ningxia, Shaanxi, Shanxi, Hebei, Beijing, Liaoning, Jilin, Heilongjiang. According to our results, in 2050s, the total suitable habitat area of R. idaeus will increase under SSP1-2.6 and then will be decreased with climate change, while in the 2090s, the total suitable habitat area will continue to decrease. From the present to the 2090s, the centroid distribution of R. idaeus in China will shift towards the east and the species will always be present in Inner Mongolia. Our results provide wild resource information and theoretical reference for the protection and rational utilization of R. idaeus. [ABSTRACT FROM AUTHOR]

The coupling effects of clamping pressure and catalyst distribution are comprehensively considered to improve proton exchange membrane fuel cell (PEMFC) performance. Numerical models were constructed to study the performance changes and the corresponding internal states of PEMFC under different clamping pressures. Since the increased clamping pressure reduces the uniformity of current density, non-uniform designs with decreased catalyst loading under channel and increased catalyst loading under rib are proposed for performance improvement. A weighted objective function considering current density magnitude and uniformity was constructed, and the performances of different catalyst loading distributions were analyzed. Compared to the uniform distribution, the optimized distribution with a variation of −15% and 15% under channel and rib had the maximum objective function value of 17.24%. The deformation analysis of the gas diffusion layer and optimization of catalyst loading distribution based on deformation analysis provided a reference for the assembly of PEMFC and the production of MEA. [ABSTRACT FROM AUTHOR]

Ultra-high-pressure tubular reactors are crucial pieces of equipment for polyethylene production. Long-term operation under high temperature, high pressure, and other extremely harsh conditions can lead to various defects, with circumferential cracks posing a major safety risk. Detecting cracks is challenging, particularly when they are under a protective layer of a certain thickness. This study designed a pulsed eddy current differential probe to detect circumferential cracks in ultra-high-pressure tubular reactors, with the lift-off distance acting as a protective layer. Detection models for traditional cylindrical and semi-circular excitation differential probes were established using finite element simulations. Corresponding experiments under different lift-off conditions were carried out, and the model's accuracy was verified by the consistency between the simulation results and experimental data. The distribution of the eddy current field under different conditions and the disturbances caused by cracks at various positions to the detection signal were then calculated in the simulations. The simulation results showed that the cracks significantly disturbed the eddy current field of the semi-circular excitation differential probe compared with that of the traditional cylindrical probe. The designed differential probe effectively detected circumferential cracks of specific lengths and depths using the difference in the voltage signals. The experimental results were in agreement with the simulation results, showing that the designed probe could effectively detect 20 mm-long circumferential cracks at a lift-off of 60 mm. The experimental results also show that the probe's detection coverage area in the axial direction varied with the lift-off height. The probe design and findings are valuable for detecting cracks in ultra-high-pressure tubular reactors with protective layers. [ABSTRACT FROM AUTHOR]

This paper introduces a novel finite control set predictive direct power control method for grid‐connected converters without cost function evaluations. Unlike conventional predictive direct power control, since the proposed method does not use the model parameters, their uncertainties do not cause prediction error and inappropriate voltage vector selection. The method employs a new form of voltage vector selection based on the slopes of active and reactive powers. The slopes are predicted in a manner with a low sensitivity to sampling noise, without updating a look‐up table, and recursive methods. Hence, there are no stagnation and convergence issues. Also, the proposed method avoids startup problems caused by data‐lacking due to directly regulating the active and reactive power by a switching logic. Flexible power oscillations control with balanced sinusoidal grid currents without any signal sequence extraction can also be achieved under this method in unbalanced grid conditions. The proposed method is assessed by both simulation and experimental studies, and its performance is compared with existing robust combined and model predictive control methods. The outcomes highlight the influence of the proposed approach and establish its superiority over the other considered methods. [ABSTRACT FROM AUTHOR]

Global climate change is one of the most critical challenges facing natural ecosystems. As sedentary organisms, plant communities are especially vulnerable, with climate change significantly impacting their development, productivity, and distribution. This study focuses on modelling and mapping the potential distribution of black pine (Pinus nigra) within the Antalya Regional Forest Directorate under the SSP1 2.6 climate scenario for the years 2040, 2060, 2080, and 2100. The MaxEnt modelling method, combined with the HadGEM3-GC31-LL climate model from WorldClim, was used to assess the impact of climate change on black pine. The current distribution model results showed "good" predictive performance, with AUC values of 0.855 for training data and 0.851 for testing data. Key variables influencing the model included precipitation during the wettest quarter, annual precipitation, maximum temperature of the warmest month, and elevation. Projections indicate that the black pine's distribution will shrink by 2040, become increasingly fragmented by 2060, and decline further by 2080, with near-total disappearance by 2100. In conclusion, this study highlights the urgent need for adaptive management strategies to address the effects of climate change on black pine forests. [ABSTRACT FROM AUTHOR]

Climate change has a pivotal impact on the potential distribution of endangered and relic tree species. Probably due to unrepresentative sampling and single algorithm, at present, there are different views on the potential range of the endangered tree Emmenopterys henryi, endemic to China. Here, we first collated 612 occurrence records and 22 environmental variables including climate, topography, and soil. Combined the Biomod2 with MaxEnt, we then predicted its past, current, and future potential suitable area in China, and determined the key factors influencing its distribution. The ensemble model results showed that the main environmental variables affecting this species were the minimum temperature of the coldest month (BIO6), precipitation of warmest quarter (BIO18), and temperature seasonality (BIO4). Its current potential distribution area was 176.53 × 104 km2, mainly concentrated in eastern, central, and southwestern China. Collectively, the suitable area of E. henryi would averagely decrease by 3.90% in all 16 future scenarios, with its centroid largely migrating northeastward. Our findings indicate that the endangered E. henryi covered 18 provinces in China, having a larger area than known. Moreover, climate change may have an adverse effect on its potential distribution. In addition, the ensemble model can produce more effective prediction outcomes than MaxEnt for such endemic tree species with large environmental range. We recommend increasing sample representativeness by analyzing the completeness properties of sample coverage, and simultaneously selecting appropriate algorithms to ensure the reliability of distribution prediction for endangered and relict tree species. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used to project how species distributions may vary over time, particularly in response climate change. Although the fit of such models to current distributions is regularly enumerated, SDMs are rarely tested across longer time spans to gauge their actual performance under environmental change. Here, we utilise paleozoological presence/absence records to independently assess the predictive accuracy of SDMs through time. To illustrate the approach, we focused on modelling the Holocene distribution of the hartebeest, Alcelaphus buselaphus, a widespread savannah‐adapted African antelope. We applied various modelling algorithms to three occurrence datasets, including a point dataset from online repositories and two range maps representing current and 'natural' (i.e. hypothetical assuming no human impact) distributions. We compared conventional model evaluation metrics which assess fit to current distributions (i.e. True Skill Statistic, TSSc, and Area Under the Curve, AUCc) to analogous 'paleometrics' for past distributions (i.e. TSSp, AUCp, and in addition Boycep, F2‐scorep and Sorensenp). Our findings reveal only a weak correlation between the ranking of conventional metrics and paleometrics, suggesting that the models most effectively capturing present‐day distributions may not be the most reliable to hindcast historical distributions, and that the choice of input data and modelling algorithm both significantly influences environmental suitability predictions and SDM performance. We thus advocate assessment of model performance using paleometrics, particularly those capturing the correct prediction of presences, such as F2‐scorep or Sorensenp, due to the potential unreliability of absence data in paleozoological records. By integrating archaeological and paleontological records into the assessment of alternative models' ability to project shifts in species distributions over time, we are likely to enhance our understanding of environmental constraints on species distributions. [ABSTRACT FROM AUTHOR]

Simple Summary: The water primrose (Ludwigia peploides) is believed to have been planted as an ornamental aquatic plant in South Korea. It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites. The species was observed to primarily inhabit aquatic environments but were also observed to inhabit moist terrestrial areas such as riverbanks or wet grasslands. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing vital information for the development of effective management strategies. The number of alien species introduced into South Korea continues to increase over the years. In particular, several plants have been introduced as ornamentals. Ludwigia peploides, which is native to the Americas and Australia, is believed to have been planted as an ornamental aquatic plant called "water primrose" and "primrose". It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites, with high-density mats of a single species forming along the water's edge and on the water surface. The maximum distribution area was 13,922 m2 in Chilgok Reservoir in Anseong. Stems and plant fragments transported along waterways were continuously forming colonies through vegetative propagation. When evaluating the overall risk, it is determined that L. peploides has a high potential to cause significant damage to the ecosystem if not managed promptly. Therefore, continuous monitoring is necessary to effectively manage and prevent the habitat expansion of L. peploides. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing essential data for ecological risk assessment and the development of effective management strategies. [ABSTRACT FROM AUTHOR]

Simple Summary: The Syringophilidae family is one of the most diverse groups of prostigmatic mites (Acari: Prostigmata) parasitising birds. In this paper, we describe a new genus and species, Corvisyringophilus krummi, which parasitises the Common Raven (Corvus corax) in Iceland. This new genus belongs to a group of primitive genera that retain a complete set of idiosomal and leg setae. Our phylogenetic analysis suggests that Corvisyringophilus is morphologically closely related to the genera Blaszakia Skoracki & Sikora, 2008 and Charadriphilus Bochkov & Mironov, 1998, which are associated with birds of different and phylogenetically unrelated orders: Musophagiformes and Charadriiformes, respectively. This research highlights the importance of examining the genus Corvus in order to better understand the specialised host–parasite relationships. Furthermore, the study emphasises the significance of using museum collections to study parasitic interactions. Syringophilidae is one of the most species-rich families in the superfamily Cheyletoidea, comprising approximately 420 species across 62 genera and two subfamilies. In this paper, we propose a new genus, Corvisyringophilus, and a new species, C. krummi gen. n. et sp. n., found in the wing covert quills of the Common Raven, Corvus corax Linnaeus, in Iceland. Corvisyringophilus is placed among the primitive genera of syringophilid mites, which possess the full complement of idiosomal and leg setae. Phylogenetic analysis based on morphological characters suggests that this genus forms a sister clade to Blaszakia Skoracki & Sikora, 2008, and Charadriphilus Bochkov & Mironov, 1998, which inhabit birds of the orders Musophagiformes and Charadriiformes, respectively. The study proposes that the current distribution patterns of quill mites, based on their morphological characteristics, may result from multiple host switching followed by co-speciation events, highlighting the complex evolutionary dynamics within this family. [ABSTRACT FROM AUTHOR]

Resolving laser-driven electron dynamics on their natural time and length scales is essential for understanding and controlling light-induced phenomena. Capabilities to reveal these dynamics are limited by challenges in interpreting wave mixing of a driving and a probe pulse, low energy resolution at ultrashort time scales and a lack of atomic-scale resolution by standard spectroscopic techniques. Here, we demonstrate how ultrafast x-ray diffraction can access fundamental information on laser-driven electronic motion in solids. We propose a method based on subcycle-resolved x-ray-optical wave mixing that allows for a straightforward reconstruction of key properties of strong-field-induced electron dynamics with atomic spatial resolution. Namely, this technique provides both phases and amplitudes of the spatial Fourier transform of optically-induced charge distributions, their temporal behavior, and the direction of the instantaneous microscopic optically-induced electron current flow. It captures the rich microscopic structures and symmetry features of laser-driven electronic charge and current density distributions. Manipulation of materials properties by laser driving can lead to future technological applications, but a complete picture of its mechanisms is missing. In their paper, authors propose a method based on ultrafast x-ray diffraction that allows for resolving laser-driven electron dynamics on their natural time and length scales. [ABSTRACT FROM AUTHOR]

Decision support systems are being developed to assist clinicians in complex decision-making processes by leveraging information from clinical knowledge and electronic health records (EHRs). One typical application is disease risk prediction, which can be challenging due to the complexity of modelling longitudinal EHR data, including unstructured medical notes. To address this challenge, we propose a deep state-space model (DSSM) that simulates the patient's state transition process and formally integrates latent states with risk observations. A typical DSSM consists of three parts: a prior module that generates the distribution of the current latent state based on previous states; a posterior module that approximates the latent states using up-to-date medical notes; and a likelihood module that predicts disease risks using latent states. To efficiently and effectively encode raw medical notes, our posterior module uses an attentive encoder to better extract information from unstructured high-dimensional medical notes. Additionally, we couple a predictive clustering algorithm into our DSSM to learn clinically useful representations of patients' latent states. The latent states are clustered into multiple groups, and the weighted average of the cluster centres is used for prediction. We demonstrate the effectiveness of our deep clustering-based state-space model using two real-world EHR datasets, showing that it not only generates better risk prediction results than other baseline methods but also clusters similar patient health states into groups. [ABSTRACT FROM AUTHOR]

Atlantic White Cedar (Chamaecyparis thyoides) (AWC) anchors a globally threatened ecosystem that is being impacted by climate change, as these trees are vulnerable to hurricane events, sea-level rises, and increasing salinity at the forest–marsh ecotone. In this study, we determined the current amount and distribution of AWC in an area that is experiencing sea-level rises that are higher than the global average rate. We used a combination of a field investigation and aerial photo interpretation to identify known locations of AWC, then integrated Sentinel-1 and 2A satellite data with abiotic variables into a species distribution model. We developed a spectral signature of AWC to aid in our understanding of phenology differences from nearby species groups. The selected model had an out-of-bag error of 7.2%, and 8 of the 11 variables retained in the final model were derived from remotely sensed data, highlighting the importance of including temporal data to exploit divergent phenology. Model predictions were strong in live AWC stands and, accurately, did not predict live AWC in stands that experienced high levels of mortality after Hurricane Sandy. The model presented in this study provides high utility for AWC management and tracking mortality dynamics within stands after disturbances such as hurricanes. [ABSTRACT FROM AUTHOR]

This paper proposes a novel THz band 2-D wide-angle scanning phased-array antenna (PAA) based on a decoupling surface. The simulated S11 bandwidth under periodic boundary conditions is 106–119 GHz, with stable gain within the bandwidth. The designed decoupling surface effectively reduces the coupling between elements, and the simulated active VSWR performance and ground surface current distribution under periodic boundary conditions confirm this. An 8 × 8 (64-element) planar PAA is modeled and simulated in CST2022 to verify the beam-scanning performance of the PAA. According to the simulation results, a 2-D wide-angle scanning of ±48° is achieved in the 106–114 GHz range, while in the 115–119 GHz range, a wide-angle scanning of ±48° is achieved on the E-plane, and the beam-scanning range on the H-plane reaches ±40°. Moreover, the normal peak gain is stably maintained at 21.9–22.8 dBi, with a normalized radiation efficiency as high as 95%, and the scanning radiation efficiency is higher than 81%. Due to its stable gain and 2-D wide-angle scanning performance, the proposed PAA has a broad application prospect in terahertz wireless communication equipment. [ABSTRACT FROM AUTHOR]

Hollow Enemy Towers, as iconic structures of the Ming Great Wall, are renowned for their roles in defense surveillance, weapon storage, and firearm operation. Recent studies have indicated that certain Hollow Enemy Towers along the Ji Town section of the Ming Great Wall also serve the function of Beacon Towers for beacon signaling. However, previous studies have not definitively determined if these towers were distinctively marked, nor have they provided a comprehensive account of their current distribution and original historical appearance. This paper initially examined the historical documentation of white lime markings employed on the outer walls of certain Hollow Enemy Towers, which served as Beacon Towers during the middle and late Ming periods. Utilizing multidisciplinary methodologies, this research identified remains of lime markings of the Beacon-Equipped Hollow Enemy Towers along the Ji Town section of the Ming Great Wall, illustrating their extensive distribution. We analyzed the material composition and construction techniques of the lime mortar. This analysis clarifies the scope of lime plastering on the exterior walls of these towers and offers a point of reference for restoring their original historical appearance. The results make a significant supplement to the types of signaling structures on the Great Wall, enriching existing understanding of the original appearance of the Great Wall's historical landscape. [ABSTRACT FROM AUTHOR]

The charging load of electric vehicles (EV) is one of the most rapidly increasing loads in current power distribution systems. It may cause distribution transformer/feeder overload without proper coordination or control, especially in residential area where household load and EV charging load are sharing transformer capacity. Existing smart meter-based orderly charging control (OCC) approaches commonly require costly but unreliable communication schemes to control EV charging behavior. In this work, a smart meter-based distributed controller is designed to establish a meter-to-EV communication interface with low cost and enhanced reliability, based on the state-of-the-art charging standard. An event-driven OCC algorithm is developed, and then, deployed in the data hub (concentrator) of the AMI with an easy-to-implement optimization formulation. The effectiveness of the proposed approach is validated using a numerical case study and a practical field test in Hangzhou, China. Both results indicate promising advantages of the proposed OCC approach in reducing the peak load of emerging EV charging demand by more than 30 % . [ABSTRACT FROM AUTHOR]

Because of the low voltage level and high current in the distribution system, as well as the high ohmic resistance of the conductors, the majority of power system losses are attributed to the distribution system. As a result, it is necessary to address the issue of reducing distribution system losses. To reduce losses in distribution systems, a wide variety of methods and algorithms have been proposed and are still being developed. The allocation of capacitors in a distribution system is one of the earliest and most effective methods for reducing system losses. With the growth of distributed generations and the diversity of their productive power, the use of capacitors in distribution systems has decreased slightly. Distributed generation resource allocation has replaced this method. Conversely, the reconfiguration of distribution systems has proven to be one of the easiest and cheapest methods for reducing distribution system losses in the past half‐century. Distribution system reconfiguration has been the subject of many studies, each with different objectives. Many studies have also reconfigured the distribution system on a daily and hourly basis. A novel method for dynamic distribution network reconfiguration is presented in this study, which utilizes capacitors and distributed generation resources simultaneously. This method divides 24 h into several periods instead of considering real‐time and hourly data. By reconfiguring and allocating capacitors and distributed generation resources during these periods, the voltage profile is improved and losses are reduced. An IEEE 33 bus network is used to test the simulations. A genetic algorithm was used to reduce losses and improve the voltage profile using MATLAB software. Based on the simulation results, this model provides better results than previous approaches. [ABSTRACT FROM AUTHOR]

Introduction: Soft rot Pectobacteriaceae (SRP) bacteria are globally dispersed pathogens that cause significant economic loss in potato and other crops. Our understanding of the SRP species diversity has expanded in recent years due to advances and adoption of whole-genome sequence technologies. There are currently 34 recognized SRP species that belong to the Dickeya and Pectobacterium genera. Methods: We used whole-genome sequencing based analysis to describe the current distribution and epidemiology of SRP isolated from diseased potato samples obtained from commercial potato cropping systems in the United States. Our primary objectives in the present study were to: (1) identify the species of these SRP isolates recovered from potato samples across 14 states in the US, (2) describe the variation among SRP isolates from various US locations and track their temporal changes, and (3) evaluate the evolutionary relationships among these SRP isolates to deduce their source. We collected 118 SRP strains from diseased potato plants and tubers in 14 states between 2015 and 2022. Results: We identified three Dickeya and eight Pectobacterium species from diseased potato samples. Dickeya dianthicola, Pectobacterium parmentieri, P. carotovorum, and P. versatile appeared to be the predominant species, constituting 83% of the isolates. Furthermore, all D. dianthicola strains studied here as well as 90% of US D. dianthicola isolates sequenced to date exhibit significant clonality. Discussion: The prevalence of this specific group of D. dianthicola, temporally and geographically, aligns with the occurrence of blackleg and soft rot outbreaks in the northeastern US after 2014. The genomic diversity observed in P. parmentieri implies multiple introductions to the US from at least four distinct sources, earlier than the arrival of the predominant group of D. dianthicola. In contrast, P. carotovorum and P. versatile appear to be widespread, long-term endemic strains in the US. [ABSTRACT FROM AUTHOR]

The discovery of the quantum Hall effect has established the foundation of the field of topological condensed matter physics. An amazingly accurate quantization of the Hall conductance, now enshrined in quantum metrology, is stable against any reasonable perturbation due to its topological protection. Conversely, the latter implies a form of censorship by concealing any local information from the observer. The spatial distribution of the current in a quantum Hall system is such a piece of information, which, thanks to spectacular recent advances, has now become accessible to experimental probes. It is an old question whether the original and intuitively compelling theoretical picture of the current, flowing in a narrow channel along the sample edge, is the physically correct one. Motivated by recent experiments locally imaging quantized current in a Chern insulator (Bi, Sb)2Te3 heterostructure [Rosen et al., Phys. Rev. Lett. 129, 246602 (2022); Ferguson et al., Nat. Mater. 22, 1100-1105 (2023)], we theoretically demonstrate the possibility of a broad "edge state" generically meandering away from the sample boundary deep into the bulk. Further, we show that by varying experimental parameters one can continuously tune between the regimes with narrow edge states and meandering channels, all the way to the charge transport occurring primarily within the bulk. This accounts for various features observed in, and differing between, experiments. Overall, our findings underscore the robustness of topological condensed matter physics, but also unveil the phenomenological richness, hidden until recently by the topological censorship--most of which, we believe, remains to be discovered. [ABSTRACT FROM AUTHOR]

The transformer grounding is typically inserted across a transformer or generator's ground. In a transformer and generator, this ground is often used to reduce the current of a disturbance from phase to earth. During a ground fault in a transformer, a very high current can flow, posing a danger to equipment and personnel. By connecting a resistor between the neutral point of the transformer and ground, the NGR limits this fault current. In the following paper, the protection mechanism of two high-voltage to medium-voltage transformers which connected in parallel during routine operation as well as in emergency situations will be explored. Protecting two parallel transformers with two different neutral grounding resistors involves ensuring proper coordination of protective devices to detect and isolate faults while minimizing damage to equipment and ensuring system stability. Another scenario under discussion involves a generator linked to the medium-voltage (MV) system, which distinct had a distinct ground value. A short circuit occurring in different neutral grounding resistor (NGR) systems refers to a fault scenario where more than one transformer or generator linked in parallelly, each with its own NGR of varying resistance values. This situation poses challenges for protection coordination and fault current distribution. To address this issue, a protective scheme is suggested, which modifies its configurations according to the operational status of the system. [ABSTRACT FROM AUTHOR]

The ghost bat Macroderma gigas (Megadermatidae) is native to Australia. Its current distribution has dramatically contracted northwards in the past 150 years and the extant populations are scattered and isolated due to climatic and anthropogenic factors. To investigate the potential for reintroductions of wild ghost bats into suitable habitats, we examined the potential for refuges located in the southern-most parts of the species' former range to once again support populations. We identified Drovers Cave, located in Drovers Cave National Park in Western Australia, as a potential reintroduction site and used thermo-hygrochron iButtons to demonstrate that the microclimate conditions within the cave are suitable for ghost bats with temperatures close to 20 °C and 99% humidity throughout a ten-month period (December to September). We also showed that in the Pilbara region, ghost bats are opportunistic and flexible predators relying on small birds and mammal species. After comparing these data with the local fauna species list reported from Drovers Cave National Park, we concluded that the habitat at the proposed reintroduction site could provide sufficient diversity of potential prey species in terms of species richness, but we had no data on their relative abundance. [ABSTRACT FROM AUTHOR]

Climate change has been disturbing the present species distribution ranges, resulting in the shifting of cultivation areas and decreases in production and quality. Tea (Camellia sinensis L.), which seeks optimum climatic resources, is a key cash crop economically in Kenya. In this study, the shifting of tea suitability was projected with the MaxEnt model under the SSP (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) climate scenarios for the 2050s and 2090s relative to the 1970–2000 distribution. Analysis under the current climatic condition showed that the proportions of optimal and medium- and marginal-suitable areas were 2%, 3%, and 24% of the total area, respectively, and located in south-western (SW), central, and north-eastern (NE) Kenya and, to some extent, in the Rift Valley. It was projected that the potential suitable tea-growing areas would migrate from the western areas to the central, eastern, and north-eastern highlands in Kenya. It was detected that the precipitation of the driest period (July), precipitation of the wettest quarter (April, May, and June), and annual temperature range could be the main climatic factors determining the shift in tea distribution. Compared to the current distribution (29%), the climatically suitable areas for tea production could reach 32.58% of Kenya's land area under the SSP1-2.6 scenarios in the 2050s and 35.08% in the 2090s under the SSP5-8.5 scenario. On the contrary, it was found that the optimal climate-suitable habitats were projected to shrink by 2% and 1% in the 2050s and 2090s under all scenarios on the west side of the Great Rift Valley compared to the current distribution. In comparison, the sizes of medium- and marginal-suitable habitats would increase by 1% and 3%, respectively. The findings indicated that unless adaptive climate actions are taken, climate change could reduce the tea planting areas in western Kenya. Meanwhile, climate suitability was projected to expand upward on the east side of the Rift Valley, enhancing the potential distribution of tea. The developed climate information could be used to design and implement adaptation interventions in the lower elevation areas. Finally, we highlight that the available scientific literature on the climate suitability of tea in Kenya should be broadened by adding non-climatic factors. [ABSTRACT FROM AUTHOR]

The dried roots of Scutellaria baicalensis (S. baicalensis) have been widely used as a traditional medicine. Recently, climate change and human activities have caused the degeneration of its wildlife habitat. However, there is rare knowledge on the effect and interactive effect of different variables on the spatial heterogeneity of S. baicalensis and how the pattern of suitable cultivation area in China would shift in response to climate change. Based on the Geodetector and Habitat Suitability Index (HSI) method, we proposed an assessment model to identify the critical environmental variable(s) affecting the distribution of suitable cultivation area for S. baicalensis in China and to project its shift under climate change. The results showed that soil and mean annual temperature are two determining variables in its spatial heterogeneity in China. Compared to 1981–2010, future climate change may result in a decrease in its suitable area, and yet may result in an increase in the extremely suitable area (about 1.00–1.35 million km2). S. baicalensis in the southern and northwestern part of its current distribution and the southwestern part and small area of northern China may experience expansion during the 21st century, while S. baicalensis in southern China, the Huang-Huai-Hai plain, and the midwest of northwestern China may experience contractions. Meanwhile, climate warming is expected to shift its distribution northwest through an expansion at the northern (at least 84 km) and western (at least 62 km) boundary and contraction at the southern (at least 529 km) boundary, respectively. These results could provide valuable information to policy-makers for the conservation and scientific introduction of S. baicalensis. [ABSTRACT FROM AUTHOR]

Simple Summary: Hydrocera triflora is primarily distributed across southeastern and southern Asia and is classified as endangered within China. The impact of climate change on the spatial distribution of this species remains uncertain. In this study, we employed the MaxEnt model to examine the migration patterns of H. triflora under the influence of climate change. Our findings indicate that the current potential distribution area is more extensive than during the three historical periods analyzed. Furthermore, projections suggest that the potential habitable area for H. triflora will continue to expand to higher altitudes by the year 2100. It is advised that protected areas be established within the current core distribution regions. Concurrently, public awareness and educational initiatives should be enhanced to mitigate the impact of human activities on wild populations. Strengthening the conservation of wild resources is imperative. Hydrocera triflora is a perennial herb found in southeastern and southern Asia. In China, it is only found in Hainan Province. With global climate change, studying the impact of climate change on the distribution of H. triflora can provide a theoretical basis for the scientific protection of this species. In this study, the MaxEnt model was used to predict the potential distribution area of H. triflora in China under historical, current, and future periods based on 66 distribution points and 12 environmental variables. The results were as follows: (i) The main environmental variables affecting the distribution of H. triflora were precipitation in the coldest month and in the wettest quarter, with elevation also being a significant factor. (ii) Over the past three periods, the last interglacial, last glacial maximum, and mid-Holocene, the suitable area for H. triflora initially decreased and then increased. The suitable area reached the lowest value in the last glacial maximum period, at only 27.03 × 104 km2. (iii) The current potential distribution area is 67.81 × 104 km2, and the optimal area is mainly distributed in the Guangxi, Guangdong, and Hainan provinces. (iv) Under future climate scenarios, the potential distribution area of H. triflora is projected to increase by 11.27~90.83 × 104 km2. It is expected to reach a maximum value (158.64 × 104 km2) in 2081~2100 under the SSP-585 climate scenario, with the distribution centroid shifting to higher latitudes. The newly gained optimal habitats will provide potential areas for introduction and ex situ conservation of this species. [ABSTRACT FROM AUTHOR]

Simple Summary: Lucanidae (stag beetles) is a small family and one of the most ancient groups within the Scarabaeoidea superfamily. Most adult lucanids exhibit clear sexual dimorphism, with males often having impressive mandibles that are used in fierce competition for mates. Fossils of Lucanidae from the Mesozoic era are rare. In this study, we describe a new lucanid fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., found in mid-Cretaceous Burmese (Kachin) amber, which shares similar features with the modern Lampriminae. This discovery marks the first fossil record of Lampriminae in mid-Cretaceous amber from northern Myanmar and is the oldest reliable record of the subfamily. The well-developed mandibles and curved claws of Prostreptocerus Yu & Cai provide additional evidence for sexual dimorphism and combat behavior in Mesozoic lucanids. This new taxon also enhances our understanding of early biodiversity and the biogeographic implications of stag beetles. A new stag beetle fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., is described based on a single male specimen. This is the first representative of the subfamily Lampriminae (Coleoptera: Scarabaeoidea: Lucanidae) from mid-Cretaceous Burmese amber. The new species is distinctive among Lucanidae due to its well-developed, right-angled mandible, frons featuring a pair of large protuberances, a coarse and sparsely punctate elytral disc, and large tubercles on the humeri. Prostreptocerus Yu & Cai is placed within Lampriminae based on several key characteristics. Morphologically, it is most similar to the extant Streptocerus Fairmaire, 1850. The current distribution of Streptocerus and Lampriminae is primarily restricted to the Southern Hemisphere, suggesting that this lineage is ancient and existed on Gondwanaland, which has significant geographical implications. This discovery extends the fossil record of Lampriminae and provides additional evidence for the existence of sexual dimorphism and potential combat behavior in Mesozoic lucanids. Additionally, Electraesalopsis Bai, Zhang & Qiu, 2017, previously placed as Lucanidae incertae sedis, shares many characteristics with Prostreptocerus Yu & Cai and is also assigned to Lampriminae based on a suite of traits. [ABSTRACT FROM AUTHOR]

Climate change is a major threat to the Middle East and North Africa (MENA) region, which can cause significant harm to its plant and animal species. We predicted the habitat distribution of Cataglyphis nodus (Brullé, 1833) in MENA using MaxEnt models under current and future climate conditions. Our analysis indicates that the cooler regions of the MENA are projected to experience temperature increases of 1–2 °C by 2040 and 2–4 °C by the 2070s. Similarly, the warmer regions may anticipate rises of 0.5–2 °C by 2040 and 2–4 °C by the 2070s. MaxEnt model results for the current climate show good agreement with observations (mean area under the curve value of 0.975 and mean true statistical skill value of 0.8), indicating good potential habitat suitability for C. nodus. Significant factors affecting habitat suitability are elevation, mean monthly precipitation of the coldest quarter, temperature seasonality, and precipitation amount of the driest month. The research predicts that under Shared Socioeconomic Pathway (SSP) 1.2.6, the habitat suitability area may increase by 6% in 2040, while SSP 3.7.0 (0.3%) and SSP 5.8.5 (2.6%) predict a decrease. For 2070, SSP 5.8.5 predicts a 2.2% reduction in habitat suitability, while SSP 1.2.6 (0.4%) and SSP 3.7.0 (1.3%) predict slight increases. The results provide insight into the potential impacts of climate change on the species and regional biodiversity changes associated with the projected species distribution. [ABSTRACT FROM AUTHOR]

Climate change will have various impacts on the survival and development of species, and it is important to explore whether plants can adapt to future climate conditions. Dipteronia dyeriana is an endangered species with a narrow distribution in Yunnan, characterized by a small population size. However, studies on its current distribution and the impact of climate change on its future survival and distribution are very limited. In this study, the current and future (2050 and 2090) potential habitats under the SSP1-2.6, SSP3-7.0, and SSP5-8.5 scenarios were predicted using both maximum entropy (MaxEnt) and random forest (RF) models based on the current range points of D. dyeriana, soil, topographical, land cover, and climate data. The results showed that the RF model demonstrated significantly higher AUC, TSS, and Kappa scores than the MaxEnt model, suggesting high accuracy of the RF model. Isothermality (bio_3), minimum temperature of the coldest month (bio_6), and annual precipitation (bio_12) are the main environmental factors affecting the distribution of D. dyeriana. At present, the high suitability area of D. dyeriana is mainly concentrated in the eastern part of Yunnan Province and part of southern Tibet, covering an area of 3.53 × 104 km2. Under future climate change scenarios, the total area suitable for D. dyeriana is expected to increase. Although, the highly suitable area has a tendency to decrease. With regards to land use, more than 77.53% of the suitable land area (29.67 × 104 km2) could be used for D. dyeriana planting under different SSP scenarios. In 2090, the centroid shifts of the two models exhibit a consistent trend. Under the SSP1-2.6 scenario, the centroids transfer to the southeast. However, under the SSP3-7.0 and SSP5-8.5 scenarios, the centroids of high suitability areas migrate toward the northwest. In summary, this study enhances our understanding of the influence of climate change on the geographic range of D. dyeriana and provides essential theoretical backing for efforts in its conservation and cultivation. [ABSTRACT FROM AUTHOR]

Past climate changes have had large impacts on modern ecological patterns. Understanding if legacies are distinguishable in the climatic niches of extant and locally extinct taxa can provide insight into the importance of climate in extinction events. To better understand mid‐ to late‐Cenozoic New Zealand plant extinctions, which are often attributed to Cenozoic climate cooling, we identify 13 con‐familial extinct and extant New Zealand genus pairs, which have modern distributions in Australia. Using climatic niches derived from current geographic distributions in Australia, we compared (i) total niche breadth, (ii) niche overlap, and (iii) individual climate parameters, to investigate potential climate drivers of intrafamilial extinction and persistence patterns in New Zealand. A majority of New Zealand extinct genera (9 out of 13 pairs) do not indicate climate niche legacies consistent with susceptibility to extinction from changing climates, while the remaining four extinct/extant pairs show slight climatic niche legacies. Three extinct genera have warmer niches than their extant counterpart, which is consistent with extinction reflecting intolerance of cooling Cenozoic climates. The other genus pair with a climatic niche legacy has an extinct genus that is distinguished by a niche with smaller precipitation seasonality than its extant counterpart, suggesting that climate metrics other than temperature may also be important extinction drivers in some taxa. Our results show that the mechanisms of Cenozoic extinctions of New Zealand genera are likely more complex than taxa reaching environmental tolerances due to cooling climates. Comparisons of current climatic niches between extant and extinct sister taxa can provide useful insights into large‐scale, long‐term climatic legacies but more analyses, including trait and phylogeographic patterns, would lead to additional insights into alternative pathways of extinction. [ABSTRACT FROM AUTHOR]

Noninvasive imaging of circuit breakers under short-circuit testing is addressed by recording the magnetic field produced over an array of external sensors and by solving an inverse problem to identify the causing current distribution. The temporal and spatial resolution of the sensing chain are studied and implemented in a physical set-up. A wire model is adopted to describe electrical current distribution. Additionally, the simpler, more direct approach to evaluating the passage of electric current in front of sensors is proposed. The dynamics of suitable approximating models of the electric arc that forms across contacts is obtained and agrees with multi-physical simulations and with experimental time histories of current and voltage. The two methods are flexible and allow the analysis of different types of circuit breakers. [ABSTRACT FROM AUTHOR]

To solve the problem of the large size of traditional industrial frequency phase-shift transformers and the harmonic distortion of multi-pulse wave rectifier systems, this paper proposes a three-stage shunt zigzag power electronic phase-shift transformer based on a double-tap multi-pulse wave rectifier, which combines the power factor correction (PFC) converter with the voltage-type SPWM inverter circuit to form a power electronic converter to realize the frequency boost and power factor correction. Through AC–DC–AC conversion, the frequency of the three-phase AC input voltage is increased, the number of core and coil turns in the transformer is reduced to reduce the size of the phase-shifter transformer, a zigzag structure of the phase-shifter transformer is used to solve the unbalanced distribution of current between the diode bridges, and a passive harmonic suppression method on the DC side is used to generate a loop current by using a group of single-phase rectifier bridges to regulate the input line current of the phase-shifter transformer. The phase-shifted voltage is input into two three-phase diode rectifier bridges to rectify and supply power to the load. Simulation and semi-physical test results show that the proposed method reduces the total harmonic distortion (THD) value of the input current of the phase-shifted transformer to 7.17%, and the THD value of the grid-side input current is further reduced to 2.49%, which meets the harmonic standard and realizes the purpose of power factor correction as well as being more suitable for high-power applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach to determining the ampacity of DC and AC railway overhead contact lines, considering both operational and design factors. The ampacity of contact lines is influenced by several design parameters, including materials, cross section and the number of catenary and contact wires, etc. Additionally, the permissible long-term and short-term current values, which correspond to the permissible temperatures defined by EN 50119:2020, are affected by operational factors such as ambient temperature, solar radiation, heat exchange conditions, wind speed, wear of contact wires. Existing methods for determining the ampacity of overhead contact lines often fail to account adequately for these critical factors and lack the necessary procedures to calculate the 30 min ampacity required by EN 50119:2020. In response, the method proposed in this study adapts the procedures of IEEE 738-2012 to the specific needs of railway contact lines, taking into account the effect of contact wire wear on current distribution and overall ampacity. The proposed method offers a more realistic and practical approach to determining the ampacity of contact lines, thereby enhancing the reliability and efficiency of the traction power supply infrastructure. This method could be useful for railway infrastructure managers to ensure the safe and efficient operation under varying environmental and operational conditions. [ABSTRACT FROM AUTHOR]

The Chesapeake Logperch, Percina bimaculata, is a small fish endemic to the upper Chesapeake Bay drainage with a range significantly reduced by water quality and habitat degradation. It was described by Haldeman in 1842 and 1844 from the Susquehanna River, Pennsylvania, synonymized with the Logperch (Percina caprodes) by Jordan in 1877, and redescribed by Near in 2008. It is extirpated from the Potomac River drainage and extant in a portion of its historic range within the Susquehanna River drainage of Pennsylvania and Maryland in the United States of America. We reviewed available historic field survey information and defined the likely extent of the historic distribution of P. bimaculata and its change in response to historic environmental perturbations. We performed fisheries surveys during 2004–2023 to fill data gaps and to define the current distribution and abundance in the Susquehanna River drainage within Pennsylvania. Our surveys utilized electrofishing gears, electrified benthic trawls, and seines. Our surveys targeting P. bimaculata on the Susquehanna River and tributaries from York Haven to Holtwood, Pennsylvania, combined with available fisheries surveys conducted by others, confirm it was extirpated from that portion of the drainage. We documented the continued usage of Conowingo Pond, Susquehanna River, and tributaries below Holtwood by populations known to exist in historic field surveys. These populations appear to have been stable since at least the 1960s based on historic data and our current surveys. We documented previously unknown populations in the Octoraro Creek drainage, Octoraro Reservoir, and Muddy Run Pumped Storage Facility. Habitat utilization observations during our surveys indicate that clean sand, gravel, rubble, boulders, and large woody debris are preferred substrates. In the lower Susquehanna River and two tributaries, P. bimaculata has demonstrated a plasticity of habitat usage by continuing to occur in environments converted into impoundments by dams. In these impoundments, shorelines and connections with clean tributaries containing preferred substrates appear to be important given their utilization by P. bimaculata during our surveys. It is our opinion that the Susquehanna River and tributaries above Holtwood once again constitute suitable habitats. Conservation efforts focused on reintroductions, water quality, habitat, and connectivity have the potential to increase the extent of occurrence, abundance, and security of P. bimaculata. [ABSTRACT FROM AUTHOR]

This paper presents an integrated coil design method for inductive power-transfer (IPT) systems. Because a medium-voltage direct current (MVDC) distribution network transmits power at relatively high voltages (typically in the tens of kV), accurate fault diagnosis using high-performance sensors is crucial to improve the safety of MVDC distribution networks. With the increasing power consumption of high-performance sensors, conventional power supplies using optical converters with 5 W-class output characteristics face limitations in achieving the rated output power. Therefore, this paper proposes a safe and reliable power supply method using the principle of IPT to securely maintain the insulation distance between the distribution network and the current sensor-supply line. A 100 W prototype IPT system is investigated, and its feasibility is validated by comparing its performance with conventional optical converters. [ABSTRACT FROM AUTHOR]

To improve the current density distribution and electromagnetic performance of air-core inductors, a structural optimization method combining back-propagation(BP) neural network and genetic algorithm(GA) is proposed for the study of axial and radial spiral multi-winding inductors. The Monte Carlo method was used to extract the structural size samples of the inductors, and the training dataset was obtained through the finite element calculation of electromagnetic fields. Based on BP neural networks, nonlinear mapping models between the inductance value, volumetric inductance density, current distribution non-uniformity coefficient, and inductor structural parameters were constructed. A sensitivity analysis of the inductor inductance value affected by the structural parameters was conducted using the Sobol index calculation. Using the current distribution non-uniformity coefficient as the fitness function and the volumetric inductance density as the constraint condition, a genetic algorithm was applied to globally optimize the structural parameters of the inductor. The optimization results were verified through a finite element comparison. The results show that, under the requirement of satisfying the volumetric inductance density, the current distribution non-uniformity coefficient of the Axial Helical Inductor (AHI)-type inductor was reduced by 4.57% compared with the best sample in the sampling, while that of the Radial Helical Inductor (RHI)-type inductor was reduced by 5.33%, demonstrating the practicality of the BP-GA joint algorithm in the structural optimization design of inductors. [ABSTRACT FROM AUTHOR]

The accurate representation of lithium plating and aging phenomena has posed a persistent challenge within the battery research community. Empirical evidence underscores the pivotal role of cell structure in influencing aging behaviors and lithium plating within lithium‐ion batteries (LIBs). Available lithium‐ion plating models often falter in detailed description when integrating the structural intricacies. To address this challenge, this study proposes an innovative hierarchical model that intricately incorporates the layered rolling structure in cells. Notably, our model demonstrates a remarkable capacity to predict the non‐uniform distribution of current density and overpotential along the rolling direction of LIBs. Subsequently, we delve into an insightful exploration of the structural factors that influence lithium plating behavior, leveraging the foundation laid by our established model. Furthermore, we easily update the hierarchical model by considering aging factors. This aging model effectively anticipates capacity fatigue and lithium plating tendencies across individual layers of LIBs, all while maintaining computational efficiency. In light of our findings, this model yields novel perspectives on capacity fatigue dynamics and local lithium plating behaviors, offering a substantial advancement compared to existing models. This research paves the way for more efficient and tailored LIB design and operation, with broad implications for energy storage technologies. [ABSTRACT FROM AUTHOR]

In this study, the Regional Ocean Modeling System (ROMS) is employed to construct a three-dimensional barotropic ocean model with a monodirectional upper boundary and homogeneous and steady wind covering the entire computation area. Eight perturbation experiments are designed to determine the vertical grid distribution difference with high resolution at the surface and bottom. Two types are considered in the model, including removing the Coriolis force (type 1) and employing a different Coriolis force (type 2). According to the experiments, the velocity of the current in type 1 yields uncertainty, and wind energy could penetrate the upper ocean and reach the abyss. The surface velocity in type 2 is fundamentally compatible with the empirical relationship constructed by Ekman, and the curved lines of the vertical distribution of horizontal currents nearly match. For type 1, the velocity is very strong from the sea surface to the bottom. When comparing type 1 and type 2 cases, the Coriolis force obstructs the wind energy transfer into the deep ocean. In addition, the European Centre for Medium-Range Weather Forecasts (ECMWF)'s global surface wind distribution indicates that the realistic ocean upper wind boundary is similar to the numerical experiment in the Pacific and Atlantic oceans, where the wind direction is along the latitude line at the equator. In order to make the experimental situation as close as possible to the real ocean, validation experiments are conducted in this study to consider the uncertainty in the current profile at the equator. The simulation results of type 1 differ significantly from the data obtained from the real ocean. This uncertainty may transfer the signal to higher latitudes, causing incorrect simulation results, especially in the critical region. Overall, this research not only makes discoveries in physical ocean theory but also guides predictive and forecasting techniques for ocean modeling. [ABSTRACT FROM AUTHOR]

Carex pilulifera L., a perennial herb native to Europe, was recently introduced and found in subalpine vegetation of Reunion Island. In this study, we assessed the current distribution and cover of C. pilulifera within the subalpine vegetation (Piton des Neiges and Piton de la Fournaise) of the National Park of Reunion. We used GLM models to analyse relationships between C. pilulifera and habitat, disturbance type, and proximity to fodder and grazing areas. We evaluated the potential distribution of C. pilulifera using species distribution models. Presence of C. pilulifera was only found on Piton de la Fournaise with a mean cover of 16.6% (where present). Carex pilulifera was the fourth most observed alien species (27% of all observations). According to the SDM, it could also occur in Piton des Neiges but was not found. Carex pilulifera was significatively more present in subalpine grasslands and close to grazing and fodder areas. We believed fodder and grazing areas to be the introduction pathways of this species. This study confirmed the status of C. pilulifera as an invasive species in the subalpine vegetation of Reunion Island which comprises a high level of plant endemism. We suggest that management should primarily focus on surveying potentially suitable areas in Piton des Neiges to eradicate new introduction and to control the species within high biodiversity areas in Piton de la Fournaise. [ABSTRACT FROM AUTHOR]

Climate change has significantly altered in the distribution of plant and animal species, potentially resulting in either species expansion or extinction. The genus Chimonanthus, an economically significant and endemic group in China, holds substantial medicinal and ornamental value; however, its wild resources are limited. There is a paucity of knowledge regarding the distribution characteristics of the genus Chimonanthus species and the critical ecological factors influencing habitat suitability. Utilizing species distribution data and environmental variables, we performed simulations and analyses to identify suitable habitats, evaluate the primary environmental factors influencing distribution, determine potential distribution areas and centroids, and predict changes in suitable areas under three future climate scenarios (SSP-126, SSP-245, SSP-585) employing MaxEnt and ArcGIS. These findings indicated that the Area Under Curve (AUC) values exceeded 0.97 for all five Chimonanthus species, suggesting that the model predictions are highly accurate. The primary environmental variables influencing the distribution of C. grammatus are temperature, particularly isothermality (BIO3), and the mean temperature of warmest quarter (BIO10). However, precipitation of warmest quarter (BIO18) was an important environmental factor limiting the distributions of C. praecox, C. nitens, C. salicifolius and C. zhejiangensis. In the current period, the area of habitat suitability for C. praecox is the largest, at 2,498,600 km2, while that for C. zhejiangensis is the smallest, at 700,400 km2. The five Chimonanthus species are distributed mainly in southern China under the current climate scenario and will migrate to higher latitudes under future climate scenarios. C. nitens had high niche overlap and range overlap with C. zhejiangensis and C. salicifolius, respectively. A similar situation occurs between C. zhejiangensis and C. salicifolius. These findings suggest that there may be strong interspecific competition among adjacent species. Our results indicate that the establishment of nature reserves at current distribution sites within optimal areas is crucial for the conservation of germplasm resources, particularly for C. grammatus and C. salicifolius. The data generated from this research can serve as a valuable reference for the selection of in situ conservation sites, the determination of appropriate planting locations, the scientific introduction of species, and the development of long-term conservation and management strategies for Chimonanthus. [ABSTRACT FROM AUTHOR]

Türkiye is one of the first regions where olives were domesticated, and olives reflect the country's millennia-old agricultural and cultural heritage. Moreover, Türkiye is one of the leading nations in olive and olive oil production in terms of quality and diversity. This study aims to determine the current and future distribution areas of olives, which is important for Türkiye's socio-economic structure. For this purpose, 19 different bioclimatic variables, such as annual mean temperature (Bio1), temperature seasonality (Bio4), and annual precipitation (Bio12), have been used. The RCP4.5 and RCP8.5 emission scenarios of the CCSM4 model were used for future projections (2050 and 2070). MaxEnt software, which uses the principle of maximum entropy, was employed to determine the current and future habitat areas of the olives. Currently and in the future, it is understood that the Mediterranean, Aegean, Marmara, and Black Sea coastlines have areas with potential suitability for olives. However, the model projections indicate that the species may shift from south to north and to higher elevations in the future. Analyses indicate that the Aegean Region is the most sensitive area and that a significant portion of habitats in the Marmara Region will remain unaffected by climate change. [ABSTRACT FROM AUTHOR]

Background. The work is aimed at developing and researching rigorous methods for solving internal problem of electrodynamics for multi-element structures (metastructures) consisting from the final number of elements, as well as to study the physical processes occurring in them. A special case of such structures are two-dimensional lattices with a fixed interelement distance, consisting of identical elements having the same spatial orientation (regular lattices). Aim. In this work, based on an iterative approach, the internal solution is solved. problems of electrodynamics for a finite regular two-dimensional lattice of spiral elements. In order to obtain a priori information about the electrodynamic characteristics of elements lattice and justification for the choice of projection function systems are analyzed spectral characteristics of the integral operator of the internal problem for a single spiral element. Then the currents on the structure elements are calculated, their spectral characteristics are determined. The results of spectral analysis allow increase the efficiency of solving an internal problem. Methods. The research is based on a strict electrodynamic approach, within the framework of which, for the specified structure in the thin-wire approximation, an integral representation of the electromagnetic field is formed, which, when considered on the surface of conductors together with boundary conditions, is reduced to a system of Fredholm integral equations of the second kind, written relative to unknown current distributions on conductors (internal task). The solution of the internal problem within the framework of the method of moments is reduced to solving a SLAE with a block matrix. Results. A mathematical model of a finite two-dimensional lattice of spiral elements is proposed radiating structure. For the specified structure, in the case of its excitation by a flat electromagnetic wave, based on the iterative approach, the internal problem of electrodynamics was solved. The following were carried out in a wide frequency range: analysis of the convergence of the iterative process, spectral analysis of the integral operator of the internal problem for a single spiral element, as well as spectral analysis of external field and current functions functions on lattice elements. Conclusion. The feasibility of determining the spectral characteristics of integral operators is shown internal task for the elements forming the metastructure. A relationship has been identified between the frequency dependence eigenvalues of the integral operator of the internal problem of single elements, forming a metastructure, with resonance phenomena arising in the metastructure, the influence of resonances on the convergence of the iterative process was confirmed. The feasibility of considering averaged amplitude current spectra is shown. It was revealed that the averaged spectrum of current functions is close to degenerate, especially near resonant frequencies. This allows for use as projection functions a compact set of eigenfunctions that have significant amplitudes in the vicinity of the frequency under study, which significantly simplifies the solution of the internal problem.

Background. The work is aimed at developing and researching rigorous methods for calculating thin-wire structures with a complex generatrix shape, having small wave sizes, as well as studying the physical processes occurring in them. A special case of such structures is a sinusoidal antenna operating in a standing current wave mode. Aim. In progress the solution of internal and external problems of electrodynamics is carried out for a sinusoidal antenna of small wave sizes located above an infinitely extended ideal reflector. The currents on the elements of the structure are calculated, its input resistance and radiation characteristics are determined. Methods. The research is based on a strict electrodynamic approach, within the framework of which, for the specified structure in the thin-wire approximation, an integral representation of the electromagnetic field is formed, which, when considered on the surface of conductors together with boundary conditions, is reduced to a system of Fredholm integral equations of the second kind, written relative to unknown current distributions on conductors (internal task). Results. A mathematical model of the radiating structure is proposed, determined: the input resistance of the structure and the basic characteristics of its radiation. It is shown that the operating range of a sinusoidal antenna in the standing wave mode is determined by the quality factor of the input impedance resonances; An increase in the width of the sinusoidal conductor leads to a decrease in the resonant frequencies of the input resistance with a simultaneous increase in the quality factor of the resonances. Conclusion. From a practical point of view, the use of the considered structure allows significantly reduce the dimensions in comparison with a thin electric vibrator, however in this case, the operating range will be correspondingly narrowed, which is determined, due to the weak dependence of the radiation characteristics on frequency, by the quality factor of the resonances. The current distribution on the generatrix of the structure can be considered as a «projection» standing surface wave localized in the plane of a sinusoidal conductor, and resulting from the superposition of forward and backward surface (slow) waves propagating at a speed significantly lower than the speed of light. To further clarify the physics of the processes occurring in the structure, one should use spectral analysis of current functions and study the distributions of the electromagnetic field in the near zone of the structure.

Abstract This paper introduces a novel finite control set predictive direct power control method for grid‐connected converters without cost function evaluations. Unlike conventional predictive direct power control, since the proposed method does not use the model parameters, their uncertainties do not cause prediction error and inappropriate voltage vector selection. The method employs a new form of voltage vector selection based on the slopes of active and reactive powers. The slopes are predicted in a manner with a low sensitivity to sampling noise, without updating a look‐up table, and recursive methods. Hence, there are no stagnation and convergence issues. Also, the proposed method avoids startup problems caused by data‐lacking due to directly regulating the active and reactive power by a switching logic. Flexible power oscillations control with balanced sinusoidal grid currents without any signal sequence extraction can also be achieved under this method in unbalanced grid conditions. The proposed method is assessed by both simulation and experimental studies, and its performance is compared with existing robust combined and model predictive control methods. The outcomes highlight the influence of the proposed approach and establish its superiority over the other considered methods.

An approximate analytical solution of a problem concerning the radiation of electromagnetic waves by regular and biconical dipoles with constant and variable complex distributed surface impedance and arbitrary excitation is derived. Solution correctness is confirm by satisfactory agreement of experimental and numerical results from well-known literary sources. Numerical results are given for the input characteristics and radiation fields of the dipoles in the cases of its symmetric and asymmetric excitation by a point source.

Pyroprocessing for the recycling of light water reactor spent fuel into metal nuclear fuel involves the electrolytic reduction process to convert oxides into metals. Optimization of the electrolytic cell is essential in the current engineering-scale development stage of electrolytic reduction research. This study investigates the effects of the conventional impermeable anode shroud, typically used in the development of laboratory-scale electrolytic reducers, and the effects of parallel multiple electrode configurations, aimed at the scale-up of the electrolytic reducer, on the current density distribution of the electrolytic reducer. The current density distribution was analyzed using COMSOL modeling. The exclusion of the impermeable anode shroud resulted in increased total currents under constant cell voltage conditions and contributed to the narrowing of the current density distribution on the electrodes. In addition, parallel multiple electrode configurations proved effective in increasing total currents and narrowing the current density distribution on the electrodes. These results emphasize the need to use a permeable anode shroud and a parallel multiple electrode configuration to scale-up the electrolytic reducer.