Differential roles of brain oscillations in numerical processing: evidence from resting-state EEG and mental number line.

Recent works point to the importance of emotions in special-numerical associations. There remains a notable gap in understanding the electrophysiological underpinnings of such associations. Exploring resting-state (rs) EEG, particularly in frontal regions, could elucidate emotional aspects, while other EEG measures might offer insights into the cognitive dimensions correlating with behavioral performance. The present work investigated the relationship between rs-EEG measures (emotional and cognitive traits) and performance in the mental number line (MNL). EEG activity in theta (3-7 Hz), alpha (8-12 Hz, further subdivided into low-alpha and high-alpha), sensorimotor rhythm (SMR, 13-15 Hz), beta (16-25 Hz), and high-beta/gamma (28-40 Hz) bands was assessed. 76 university students participated in the study, undergoing EEG recordings at rest before engaging in a computerized number-to-position (CNP) task. Analysis revealed significant associations between frontal asymmetry, specific EEG frequencies, and MNL performance metrics (i.e., mean direction bias, mean absolute error, and mean reaction time). Notably, theta and beta asymmetries correlated with direction bias, while alpha peak frequency (APF) and beta activity related to absolute errors in numerical estimation. Moreover, the study identified significant correlations between relative amplitude indices (i.e., theta/beta ratio, theta/SMR ratio) and both absolute errors and reaction times (RTs). Our findings offer novel insights into the emotional and cognitive aspects of EEG patterns and their links to MNL performance.

Main focus of parents of children with attention deficit hyperactivity disorder and the effectiveness of early clinical screening.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common mental and behavioral disorder among children. AIM: To explore the focus of attention deficit hyperactivity disorder parents and the effectiveness of early clinical screening. METHODS: This study found that the main directions of parents seeking medical help were short attention time for children under 7 years old (16.6%) and poor academic performance for children over 7 years old (12.1%). We employed a two-stage experiment to diagnose ADHD. Among the 5683 children evaluated from 2018 to 2021, 360 met the DSM-5 criteria. Those diagnosed with ADHD underwent assessments for letter, number, and figure attention. Following the exclusion of ADHD-H diagnoses, the detection rate rose to 96.0%, with 310 out of 323 cases identified. RESULTS: This study yielded insights into the primary concerns of parents regarding their children's symptoms and validated the efficacy of a straightforward diagnostic test, offering valuable guidance for directing ADHD treatment, facilitating early detection, and enabling timely intervention. Our research delved into the predominant worries of parents across various age groups. Furthermore, we showcased the precision of the simple exclusion experiment in discerning between ADHD-I and ADHD-C in children. CONCLUSION: Our study will help diagnose and guide future treatment directions for ADHD.

Comparative analysis of standard and contrast elastic resistance band training effects on physical fitness in female adolescent handball players.

This study aimed to compare the effects of two elastic band 10-week training programmes on the athletic performance in adolescent female handball players. Participants aged 16.0 ± 0.5 years were randomly assigned to control (CNT, n = 12), standard elastic band (SEB, n = 12), or contrast elastic band (CEB, n = 12) programmes, each performed twice a week supplementing the regular training. The sprint (10 m and 20 m), modified Illinois change-of-direction test (COD), squat jump (SJ), countermovement jump (CMJ), standing long jump (SLJ), back extensor strength (BES), medicine ball throw (MBT), 1-RM bench press, 1-RM half squat, repeated sprint ability, and force-velocity (F-V) tests were measured before and after the intervention. Both CEB and SEB similarly improved sprint (p < 0.01 and p < 0.01) and COD (p < 0.001 and p < 0.01) when compared to CNT. Jumping performance improved significantly (SJ p < 0.01; CMJ p < 0.05) only in CEB, compared to CNT. Strength improved in both experimental groups (p < 0.01; ES: 0.73 < d < 1.59) compared to CNT, and there was a greater increase for CEB than SEB (p < 0.05) in the medicine ball throw (Table 3). Both CEB and SEB increased all RSA scores compared to CNT (p < 0.01; ES: 0.10 < d < 1.22), without significant difference between them. All F-V scores increased significantly in CEB and SEB compared to CNT (p < 0.01; ES: 0.45 < d < 2.47). In addition, CEB showed substantial gains in performance for PPabs, PPrel, and F0 (p < 0.001, p < 0.001 and p < 0.05, respectively) compared to SEB. Ten-week elastic band training conducted within the competitive season improved limb strength, power and F-V profile in female handball players, with a superior effect of the contrast elastic band training mode for upper-limb strength and F-V characteristics.

Laboratory investigations of wave-induced transport of plastic debris over a rippled bottom.

Laboratory experiments are conducted in a wave flume to investigate the effect of water waves on the transport of plastic pellets over a rippled bottom. The horizontal velocities of plastic debris are analyzed over the rippled bottom for different wave conditions and plastic elements with different properties. Laboratory investigations determined the characteristic transport patterns of wave-induced plastic debris with a density of ∼2.0g/cm3 moving along the rippled bottom. In the first, swing-type motion, the grains move only in the ripple trough with velocities lower than 0.10 m/s. For sliding-type movement, the grains move along the entire rippled surface with velocities in the range of 0.10-0.13 m/s. For higher velocities in the range of 0.15-0.20 m/s, a saltation-type motion becomes dominant. The results show that plastic grains may move up to 2-3 cm above the ripple crest depending on hydrodynamic conditions. The analysis shows that for velocity-skewed flows, sliding-type motion and onshore transport dominate. For acceleration-skewed flows, saltation-type motion and offshore transport dominate, which is attributed to higher boundary layer thickness and phase lag effects. The analysis of the relationship between the particle Reynolds number and the thickness of the turbulent boundary layer reveals that for values of Rep≥1000 and a boundary layer thickness mm saltation-type motion becomes dominant. The direction of transport is affected not only by the density of the sediment and the wave skewness coefficients but also by the dimensions of the bottom ripples. The laboratory investigations also provide insight into the hydrodynamic conditions affecting the transport of plastic debris along the bottom covered with ripples in oscillating nonlinear water flows.

Direction-of-Arrival Estimation for Unmanned Aerial Vehicles and Aircraft Transponders Using a Multi-Mode Multi-Port Antenna.

Increasing airspace safety is an important challenge, both for unmanned aerial vehicles (UAVs) as well as manned aircraft. Future developments of collision avoidance systems are supposed to utilize information from multiple sensing systems. A compact sensing system could employ a multi-mode multi-port antenna (M 3PA). Their ability to radiate multiple orthogonal patterns simultaneously makes them suitable for communication applications as well as bearing and ranging applications. Furthermore, they can be designed to flexibly originate near-omnidirectional and/or directional radiation patterns. This option of flexibility with respect to the radiation characteristic is desired for antennas integrated in collision avoidance systems. Based on the aforementioned properties, M 3PAs represent a compelling option for aircraft transponders. In this paper, direction-of-arrival (DoA) estimation using an M 3PA designed for aerial applications is put to the test. First, a DoA estimation scheme suitable to be employed with M 3PAs is introduced. Next, the validity of the proposed method is confirmed through numerical simulations. Lastly, practical experiments are conducted in an antenna measurement chamber to verify the numerical results.

Advancing Robotic Single-Site Cholecystectomy: Innovations, Challenges, and Future Directions.

The crystalization of the components of bile within the gallbladder can lead to the formation of gallstones (cholelithiasis), which may often require surgical removal of the gallbladder, a procedure known as cholecystectomy, in symptomatic cases. Robotic single-site cholecystectomy (RSSC) is a recently introduced groundbreaking minimally invasive procedure for gallbladder removal. RSSC utilizes robotic technology, offering enhanced dexterity through a single-incision approach, promising improved outcomes such as reduced postoperative pain and superior cosmesis. However, certain limitations, such as restricted instrument movement and heightened hernia risk, necessitate a critical evaluation of this modality. Furthermore, as the widespread adoption of RSSC remains undecided due to concerns over its costs, efficiency, and overall superiority over prior models, this paper assesses future possibilities for RSSC's evolution. In vivo robotics, improved digital imaging, and re-engineering of the surgical instruments themselves are all potential avenues to augment the current RSSC design, although it is currently unclear as to what extent they could impact the procedure's viability. This review critically examines the available literature on the effectiveness and potency of RSSC compared to its predecessors in the modern healthcare setting and proposes future directions through which innovation could more firmly establish the procedure as the standard of care for cholecystectomy.

Hyperpolarization-activated currents drive neuronal activation sequences in sleep.

Sequential neuronal patterns are believed to support information processing in the cortex, yet their origin is still a matter of debate. We report that neuronal activity in the mouse postsubiculum (PoSub), where a majority of neurons are modulated by the animal's head direction, was sequentially activated along the dorsoventral axis during sleep at the transition from hyperpolarized "DOWN" to activated "UP" states, while representing a stable direction. Computational modeling suggested that these dynamics could be attributed to a spatial gradient of hyperpolarization-activated currents (Ih), which we confirmed in ex vivo slice experiments and corroborated in other cortical structures. These findings open up the possibility that varying amounts of Ih across cortical neurons could result in sequential neuronal patterns and that traveling activity upstream of the entorhinal-hippocampal circuit organizes large-scale neuronal activity supporting learning and memory during sleep.

Enhancement on migration and biodegradation of Diaphorobacter sp. LW2 mediated by Pythium ultimum in soil with different particle sizes.

Introduction: The composition and structure of natural soil are very complex, leading to the difficult contact between hydrophobic organic compounds and degrading-bacteria in contaminated soil, making pollutants hard to be removed from the soil. Several researches have reported the bacterial migration in unsaturated soil mediated by fungal hyphae, but bacterial movement in soil of different particle sizes or in heterogeneous soil was unclear. The remediation of contaminated soil enhanced by hyphae still needs further research. Methods: In this case, the migration and biodegradation of Diaphorobacter sp. LW2 in soil was investigated in presence of Pythium ultimum. Results: Hyphae could promote the growth and migration of LW2 in culture medium. It was also confirmed that LW2 was able to migrate in the growth direction and against the growth direction along hyphae. Mediated by hyphae, motile strain LW2 translocated over 3 cm in soil with different particle size (CS1, 1.0-2.0 mm; CS2, 0.5-1.0mm; MS, 0.25-0.5 mm and FS, <0.25 mm), and it need shorter time in bigger particle soils. In inhomogeneous soil, hyphae participated in the distribution of introduced bacteria, and the total number of bacteria increased. Pythium ultimum enhanced the migration and survival of LW2 in soil, improving the bioremediation of polluted soil. Discussion: The results of this study indicate that the mobilization of degrading bacteria mediated by Pythium ultimum in soil has great potential for application in bioremediation of contaminated soil.

The effects of vehicle color and travel direction on perceived speed error varies by judgment type among older pedestrians.

OBJECTIVE: Misjudgments of vehicle speed or distance frequently lead to collisions, particularly among older pedestrians who are less accurate in estimating vehicle speeds than younger individuals. However, comprehensive studies that assess multiple factors influencing speed perception in older pedestrians are lacking. METHODS: This research utilized computer simulations to explore how vehicle color (red, green, blue) and direction of travel (approaching or receding) affect perceived speed errors in both relative and absolute judgment scenarios among older pedestrians. RESULTS: Data from 38 older adults and 40 college students indicated that red vehicles were associated with fewer perceived speed errors than either green or blue vehicles. Errors increased for vehicles moving away, with absolute judgments showing greater discrepancies than relative ones. Analysis revealed that, across various combinations of the three independent variables-vehicle color, vehicle direction, and judgment type-the older participants exhibited significantly larger perceived speed errors compared to college students. Furthermore, the study identified significant interactions between vehicle color and direction, and between judgment type and vehicle direction. CONCLUSION: Our findings are beneficial in understanding the factors influencing older pedestrians' speed perceptions, aiding public safety and informing car design to ensure safer roads for older pedestrians.

Effects of Postactivation Potentiation enhacement on sprint and change-of-direction performance in athletes: A systematic review.

BACKGROUND: Training interventions like Resisted Sled Training, Complex Training, Plyometric training, and recently, Postactivation Potentiation Enhancement (PAPE) protocols are being employed by sportsmen for performance enhancement. Currently, there is no conclusive evidence on the effectiveness of the PAPE protocols and methods to integrate them into the training. The current systematic review aims to critically summarize the current evidence on PAPE protocols' effect on Sprint and Change of Direction (COD) performance in Athletes and study the influence of the Type of PAPE protocols, Recovery duration, Volumes, and loads of PAPE protocols. METHODS: A systematic computerized literature search was performed from December 2020 to June 2022 on the databases: MEDLINE (assessed by PubMed), CENTRAL (Cochrane Library Central Register of Controlled Trials), PeDro, and Science direct. The major criteria for inclusion were Athletes (Population) who performed PAPE protocol as Intervention before Sprint and/or COD assessment tests. The studies were individually assessed for Risk of Bias using EPHPP (Effective Public Health Practice Project) Tool. RESULTS: A total of sixteen studies were included. For Linear sprint, nine studies reported a significant PAPE effect whereas, six studies reported insignificant effects. Whereas, for COD performance, two studies reported insignificant results and one study reported significant CODS enhancements The recovery duration ranged from 15 s up to 16 min. CONCLUSION: PAPE protocols can be incorporated provided the recovery duration is of Moderate duration (3-8mins) or Individualized durations, using multiple sets (2-6), moderate-high loads (>85% 1-RM), type of protocol is Barbell Hip Thrust, Plyometrics or Unilateral biomechanically similar exercises to Running.

Dynamic behavior of electro-osmosis in variable charge soils: Insights on termination and direction reversal.

Electro-osmosis offers an effective method for dewatering and remediating low permeability soil. Long-term observations on nonlinear behavior of electro-osmosis and the influencing factors are not commonly reported. Connection between cessation and direction reversal of electro-osmotic flow (EOF), and the evolution of electro-chemical parameters inside of the soil mass thus remains unclear. The dynamic response of EOF in variable charge soil could be significant, whereas the investigations on which are currently lacking. A series of electro-osmotic experiments were performed with two natural variable charge soils. The results indicated that initial electro-osmotic rate was positively proportional to electric current and initial electrical conductivity of the pore fluid, which could be explained by the ion migration model. The dynamic evolution of electro-osmotic rate and electro-chemical parameters corresponding to the solute and pH conditionings at the electrode compartments demonstrated that: 1) coupling effects of non-uniform distribution of voltage gradient and pH determined the magnitude and direction of EOF rate; 2) compared to the final pHIEP value, the bigger, close and smaller values of the novel index "voltage gradient weighed mean of spatial pH″ represented the forward, terminated and reversed EOF respectively; 3) the classical Helmholtz-Smoluchowski model are proved to be more applicable interpreting the coupled nonlinearity of electro-osmosis during the later steady phase. This work would facilitate future research for a comprehensive electro-osmotic model, and provide guidance to condition the initial and boundary conditions in application of electro-osmotic dewatering and electrokinetic remediation.

Identification of environmental, socioeconomic, water, sanitation, and hygiene (WaSH) factors associated with COVID-19 incidence in the Philippines: A nationwide modelling study.

Despite the implementation of non-pharmaceutical interventions, the threat of coronavirus disease 2019 (COVID-19) remains significant on a global scale. Identifying external factors contributing to its spread is crucial, especially given the World Health Organization's recommendation emphasizing access to water, sanitation, and hygiene as essential in curbing COVID-19. There is a notable discrepancy in access to sanitation facilities, particularly evident in low- and middle-income countries. However, there is a lack of quantitative assessments regarding these factors. This study examines various environmental, socioeconomic, water, sanitation, and hygiene factors and their associations with COVID-19 incidence. All regions in the Philippines were categorized into clusters based on socioeconomic factors. A conceptual structural equation model (SEM) was developed using domain knowledge. The best-fitting SEM for each cluster was determined, and associations between factors and COVID-19 incidence were estimated. The correlation analysis revealed that rainfall, minimum temperature, and relative humidity were positively correlated with weekly COVID-19 incidence in urban regions. Maximum temperature, mean temperature, wind speed, and wind direction were negatively correlated with weekly COVID-19 incidence in rural regions, with time lags of 0, 3, and 7 weeks. In urban regions (Cluster 1), factors such as urbanization rate (1.00), area (-0.93), and population (0.54) were found to be associated with weekly COVID-19 incidence. Conversely, in rural regions (Cluster 2), factors including area (0.17), basic sanitation (0.84), and wind direction (0.83) showed associations with weekly COVID-19 incidence. These factors were causally associated with a latent variable reflecting the hidden confounders associated with COVID-19 incidence. It is important to note that sanitation factors were associated only in rural regions. Improving access to sanitation facilities in rural regions of the Philippines is imperative to effectively mitigate disease transmission in future pandemics. Identification of the causal effect of unobserved confounders with COVID-19 incidence is recommended for future research.

[Basic MRI Study in the Imaging Direction of a Diffusion-weighted Whole Body with Background Body Signal Suppression].

A diffusion-weighted whole body with background body signal suppression (DWIBS) is usually imaged as a whole body with Transverse (Tra). However, Tra has a large number of stations and a larger number than Coronal (Cor), so the scan time is longer. There are also drawbacks, such as signal unevenness between series. It is known that the effect of distortion is large in Cor. There is no report on it in Sagittal (Sag). Therefore, in this study, we focused on Sag and examined the imaging time, image distortion, fat suppression effect, and continuity between stations. In the examination by the phantom, the scan time was the shortest for Cor and the longest for Sag. In the strain evaluation, the effect of strain could be suppressed compared to Cor by using a rectangle field of view (FOV) in the anterior to posterior (AP) direction in Tra and Sag. There was no difference in the fat suppression effect depending on the imaging direction. Similar results were obtained in a study of 10 healthy volunteers, with Sag having the best continuity between stations.

Human foot muscle strength and its association with sprint acceleration, cutting and jumping performance, and kinetics in high-level athletes.

The primary objective of this study was to investigate the relationship between metatarsophalangeal joint (MTPj) flexion torque and sprint acceleration, cutting and jumping performance, and kinetics. A secondary aim was to explore this relationship when MTP flexion strength was associated with other foot and lower limb neuromuscular outputs. After an initial MTPj flexion torque assessment using a custom-built dynamometer, 52 high-level athletes performed the following tasks on a force platform system: maximal sprint acceleration, 90-degree cutting, vertical and horizontal jumps, and foot-ankle hops. Their foot posture, foot passive stiffness and foot-ankle reactive strength were assessed using the Foot Posture Index, the Arch Height Index Measurement System and the Foot-Ankle Rebound Jump Test. Ankle plantarflexion and knee extension isometric torque were assessed using an isokinetic dynamometer. During maximal speed sprinting, multiple linear regressions suggested a major contribution of MTPj flexion torque, foot passive stiffness and foot-ankle reactive strength to explain 28% and 35% of the total variance in the effective vertical impulse and contact time. Ankle plantarflexor and quadriceps isometric torques were aggregately contributors of acceleration performance and separate contributors of cutting and jumping performance. In conclusion, MTPj flexion torque was more strongly associated with sprinting performance kinetics especially at high-speed.

Self-Directed Home- and Community-Based Services Improve Outcomes for Family Caregivers: A Systematic Review.

BACKGROUND AND OBJECTIVES: Self-direction is an approach that allows older adults and people with disabilities to determine the home- and community-based services they receive, including the ability to hire caregivers of their choice. Self-direction has been shown to improve outcomes for the service recipients. The promotion of choice and control in self-direction may also affect family caregivers. We conducted a systematic review examining the impact of self-direction on a broad range of caregiver outcomes. RESEARCH DESIGN AND METHODS: We conducted a systematic review guided by PRISMA guidelines. Literature search was conducted in 8 databases. We appraised risk of bias using the Joanna Briggs Institute critical appraisal checklists and assessed certainty of evidence using the GRADE framework. RESULTS: Sixteen studies meeting inclusion criteria were included. We found, with moderate certainty, that self-direction is associated with improved caregivers' personal and social well-being. Caregivers also reported reduced unmet needs and increased access to care for the care recipients under self-direction. Self-direction did not appear to reduce caregiving hours. With less certainty, self-direction was also positively associated with increased respite care use, perception of choice, and intention to continue caregiving by caregivers. DISCUSSION AND IMPLICATIONS: Beyond delivering person-centered services that improve recipient outcomes, self-direction may also improve the outcomes of family caregivers.

Distance- and Angle-Based Hybrid Localization Integrated in the IEEE 802.15.4 TSCH Communication Protocol.

Accurate localization of devices within Internet of Things (IoT) networks is driven by the emergence of novel applications that require context awareness to improve operational efficiency, resource management, automation, and safety in industry and smart cities. With the Integrated Localization and Communication (ILAC) functionality, IoT devices can simultaneously exchange data and determine their position in space, resulting in maximized resource utilization with reduced deployment and operational costs. Localization capability in challenging scenarios, including harsh environments with complex geometry and obstacles, can be provided with robust, reliable, and energy-efficient communication protocols able to combat impairments caused by interference and multipath, such as the IEEE 802.15.4 Time-Slotted Channel Hopping (TSCH) protocol. This paper presents an enhancement of the TSCH protocol that integrates localization functionality along with communication, improving the protocol's operational capabilities and setting a baseline for monitoring, automation, and interaction within IoT setups in physical environments. A novel approach is proposed to incorporate a hybrid localization by integrating Direction of Arrival (DoA) estimation and Multi-Carrier Phase Difference (MCPD) ranging methods for providing DoA and distance estimates with each transmitted packet. With the proposed enhancement, a single node can determine the location of its neighboring nodes without significantly affecting the reliability of communication and the efficiency of the network. The feasibility and effectiveness of the proposed approach are validated in a real scenario in an office building using low-cost proprietary devices, and the software incorporating the solution is provided. The experimental evaluation results show that a node positioned in the center of the room successfully estimates both the DoA and the distance to each neighboring node. The proposed hybrid localization algorithm demonstrates an accuracy of a few tens of centimeters in a two-dimensional space.

A Novel Generalized Nested Array MIMO Radar for DOA Estimation with Increased Degrees of Freedom and Low Mutual Coupling.

In array signal processing, the mutual coupling among physical sensors can inevitably affect the estimation of the direction of arrival (DOA). Despite the fact that multiple-input and multiple-output (MIMO) radar can provide greater degrees of freedom (DOFs), the influence of mutual coupling is largely overlooked in many current MIMO radar designs. To tackle this issue, we propose the utilization of a generalized nested array (GNA) in transmitter array and we introduce an expansion factor into the nested array in the receiver array. Thereby, a novel GNA-MIMO radar is put forward. The proposed MIMO radar offers O(N4) consecutive DOFs with N sensors and avoids the adverse effects of high mutual coupling caused by closely located sensors. Furthermore, we derive the closed-form expressions for the position of physical sensors and the attainable consecutive DOFs of the proposed MIMO radar. Through simulation experiments, we demonstrate the superior accuracy of the proposed MIMO configuration in DOA estimation and angle resolution under the condition of mutual coupling effect.

Pipeline Embolization Device (PED) and Flow Re-Direction Endoluminal Device (FRED) for Intracranial Aneurysms; A Comparative Systematic Review and Meta-Analysis Study.

BACKGROUND: When it comes to intracranial aneurysms, the quest for more effective treatments is ongoing. Flow diversion represents a growing advancement in this field. This review seeks to compare two variants of the endovascular flow diversion method: the Flow Re-Direction Endoluminal Device (FRED) and the Pipeline Embolization Device (PED). METHODS: A systematic review was conducted according to the PRISMA guideline using PubMed, Scopus, Web of Science, and Embase, using appropriate terms to compare PED and FRED in double-arm studies from conception until October 8th, 2023. RESULTS: The meta-analysis encompassed 1,769 patients, with a predominance of females (75.5%), among whom 973 patients underwent FRED procedures, while 651 received PED interventions. At six months, complete occlusion rates were 0.62 for FRED and 0.68 for PED (P = 0.68). At one year and the last follow-up, no significant differences were observed between FRED and PED, respectively. Adequate occlusion rates were similar between FRED and PED (0.82 vs 0.79, P = 0.68). FRED showed a statistically significant higher rate of good mRS scores at follow-up (1.00 vs. 0.97, P = 0.03). Hemorrhage and re-treatment rates were higher in PED (P < 0.01) without considering the rupture status of the aneurysms due to the lack of data. CONCLUSION: This meta-analysis suggests comparable efficacy but different safety profiles between FRED and PED in treating intracranial aneurysms. FRED demonstrated a higher rate of good mRS scores, while PED showed increased hemorrhage and re-treatment rates. Understanding these differences is crucial for informed decision-making in clinical practice.

A Circular-Linear Probabilistic Model Based on Nonparametric Copula with Applications to Directional Wind Energy Assessment.

The joint probability density function of wind speed and wind direction serves as the mathematical basis for directional wind energy assessment. In this study, a nonparametric joint probability estimation system for wind velocity and direction based on copulas is proposed and empirically investigated in Inner Mongolia, China. Optimal bandwidth algorithms and transformation techniques are used to determine the nonparametric copula method. Various parameter copula models and models without considering dependency relationships are introduced and compared with this approach. The results indicate a significant advantage of employing the nonparametric copula model for fitting joint probability distributions of both wind speed and wind direction, as well as conducting correlation analyses. By utilizing the proposed KDE-COP-CV model, it becomes possible to accurately and reliably analyze how wind power density fluctuates in relation to wind direction. This study reveals the researched region possesses abundant wind resources, with the highest wind power density being highly dependent on wind direction at maximum speeds. Wind resources in selected regions of Inner Mongolia are predominantly concentrated in the northwest and west directions. These findings can contribute to improving the accuracy of micro-siting for wind farms, as well as optimizing the design and capacity of wind turbine generators.

Study of Coating Growth Direction of 6061 Aluminum Alloy in Soft Spark Discharge of Plasma Electrolytic Oxidation.

Conventional plasma electrolytic oxidation treatments produce oxide coatings with micron-scale discharge pores, resulting in insulation and wear and corrosion resistance far below that expected of highly dense Al2O3 coatings. The introduction of cathodic polarization during the plasma electrolytic oxidation process, especially when the applied cathode-to-anode current ratio (Rpn) is greater than 1, triggers a unique plasma discharge phenomenon known as "soft sparking". The soft spark discharge mode significantly improves the densification of the anode ceramic layer and facilitates the formation of the high-temperature α-Al2O3 phase within the coating. Although the soft spark discharge phenomenon has been known for a long time, the growth behavior of the coating under its discharge mode still needs to be studied and improved. In this paper, the growth behavior of the coating before and after soft spark discharge is investigated with the help of the micro-morphology, phase composition and element distribution of a homemade fixture. The results show that the ceramic layer grows mainly along the oxide-electrolyte direction before the soft spark discharge transformation; after the soft spark discharge, the ceramic layer grows along the oxide-substrate direction. It was also unexpectedly found that, under soft spark discharge, the silicon element only exists on the outside of the coating, which is caused by the large size and slow migration of SiO32-, which can only enter the ceramic layer and participate in the reaction through the discharge channel generated by the strong discharge. In addition, it was also found that the relative phase content of α-Al2O3 in the coating increased from 0.487 to 0.634 after 10 min of rotary spark discharge, which is an increase of 30.2% compared with that before the soft spark discharge transition. On the other hand, the relative phase content of α-Al2O3 in the coating decreased from 0.487 to 0.313 after 20 min of transfer spark discharge, which was a 55.6% decrease compared to that before the soft spark discharge transformation.