Low Speed Research Articles

Improving large angle flow measurement accuracy of five-hole probe using novel calibration coefficient and accuracy progressive neural network

Novel calibration coefficients and data-fitting techniques based on a two-stage accuracy progressive neural network were developed to improve the accuracy of a five-hole probe in measuring large-angle flows. By modifying the denominator and numerator of traditional calibration coefficients, the novel coefficients can solve the singularity and multi-value problems of large-angle flow measurement. By training the neural network using both global calibration data and the calibration data of large measurement error points, the two-stage accuracy progressive neural network can effectively improve the measurement accuracy of a five-hole probe when flow separation occurs around the probe head at large flow angles. The experimental results demonstrate that applying the novel calibration coefficients and accuracy progressive neural network ensures that the calibration error of the flow angle is less than 0.8°, and the flow pressure error is less than 0.1% when the flow angle reaches 50° at low subsonic speeds.

Development of high hard TiB–TiB2 coatings on Ti implants for bio-tribological applications; applying Box-Behnken design and actual wear analyzing in simulated body fluids

This research focuses on the enhancement of the tribological behavior of commercial pure titanium (Cp-Ti) in a simulated body fluid (SBF) via surface reinforcement by titanium borides. The protective boride coatings were formed through the pack cementation process at two different temperatures (950 and 1050 °C) to create diverse hard compositions of TiB and TiB–TiB2 in the coating, with hardness of 1032 and 1291 Hv, respectively. The roughness and wettability of top surfaces were evaluated before the tribology studies due to their impacts on the tribology behavior. Box-Behnken design (BBD) was applied to investigate the effects of the wear parameters in dry and SBF environments. The duration of the wear tests was 53, 35, and 26 min for low, medium, and high speed. It was found that the abrasion wear type was dominant at the beginning of sliding, and then changed to the plastic deformation in the dry conditions, while there is no sign of the abrasion and adhesion wear features at the surface of the reinforced samples abraded in the SBF solution. Results confirmed a high coincidence between BBD predictions and actual findings. The released debris from the coatings was also investigated to find origins. Results showed that majority of the debris in the SBF solution belonged to the calcium phosphate particles demonstrating the bioactivity of the TiB–TiB2 coatings. According to findings, hard TiB–TiB2 coatings could significantly improve the tribological behavior of the Ti implants, which could in turn result in expanding the biological application of Cp-Ti.

The effect of process parameters on a continuous blending process monitored in-line by near-infrared spectroscopy

The continuous feeding-mixing system ensures the composition uniformity down to the tableting continuous manufacturing line so that a quality end-product is consistently delivered. Near-infrared spectroscopy (NIRS) enables in-line assessment of the blend's critical quality attributes in real-time. In this study, the effect of total feed rate and impeller speed on the continuous blending process monitored in-line by NIRS was examined by principal component analysis (PCA), ANOVA simultaneous component analysis (ASCA) and partial least squares (PLS) regression. Process data were generated by a factorial experimental design with process parameters and a constant formulation comprised of: 30% (wt/wt) ibuprofen, 67.5% (wt/wt) microcrystalline cellulose, 2% (wt/wt) of sodium starch glycolate and 0.5% (wt/wt) of magnesium stearate. The PCA hinted at the prevalence of impeller speed effect on ibuprofen concentration due to path length variation of the NIR light caused by the fluidized behaviour in the powder blend as a result of high speed ranges (>300 rpm). The ASCA model indicated that while both impeller speed and total feed rate effects were statistically significant (p-value=0.004), the impeller speed was the factor that contributed the most to the spectral variance (55.5%). The PLS regression model for the ibuprofen content resulted in a RMSECV of 1.3% (wt/wt) and showed that impeller speed was yet again the factor that exerted the major influence on spectral variance, owing to its wavelength-dependent effect that prevents common pre-processing techniques from eliminating it across the entire NIR range. The best sample presentation to the NIR probe was achieved at low impeller speed ranges (<600 rpm) and low total feed rates (<15 kg/h), such that it enhanced the PLS model ability to predict the ibuprofen concentration in the blend.

Effect of Expressway Exit Deceleration Markings on Distracted Drivers in China

Expressway exit areas experience traffic diversion and complex road conditions, making them accident-prone areas. In this study, transverse and fishbone visual illusion deceleration markings were selected to optimize the induction facilities at expressway exits. The research aims to investigate the impact of these markings on the driving behavior, cognitive load, and physiological characteristics of drivers in various distracted scenarios at expressway exit areas. Furthermore, a comprehensive evaluation of each experimental scheme is conducted using the Matter-Element Extension Model. The study found that the implementation of deceleration markings can effectively enhance driver alertness and lane change awareness, enabling drivers to reduce their speed to near the speed limit in exit areas without compromising driving comfort. Compared to the situation without markings, drivers begin to decelerate approximately 600 meters earlier and exit the ramp when markings are present. Fishbone deceleration markings, in contrast to transverse markings, result in lower vehicle speeds, smoother deceleration, and more effectively stimulate drivers' intention to change lanes, guiding them to make the final lane change earlier. Based on the comprehensive evaluation results, it is recommended that transverse or fishbone deceleration markings be considered in engineering practice. These markings have not produced significant effects on driver visual fatigue and driving load, with fishbone markings demonstrating superior comprehensive evaluation outcomes. These research findings can provide valuable insights for future expressway exit area marking design schemes, further enhancing driver safety.

Study on microstructure and mechanical properties of 5052 aluminum alloy MIG welded joint for high-speed train

In this paper, the MIG welding process is utilized to weld a 3 mm thick 5052 aluminum alloy plate by using ER5356 welding wire as filler. The effects of different welding speeds on the microstructure and mechanical properties of the weld are systematically studied utilizing a metallographic microscope, x-ray diffractometer, scanning electron microscope, room temperature tensile, and microhardness. It was found that there were pore defects in the samples at lower or higher welding speeds, and there was no penetration at the maximum welding speed. When the welding speed is 650 mm min−1, the weld is well-formed, the surface is flat without pores, the fish scale is evenly distributed, and the weld shows good penetration. The intermetallic compounds of all the welds are mainly composed of α(Al), Mg2Si, Al3Fe, and Al3Mg2. The mechanical properties of the samples show that the hardness of the weld reaches the maximum value of 56.7HV at this welding speed, and the tensile strength and elongation are 210 MPa and 14.3%, respectively. The fracture is located at the junction of the base metal and the heat-affected zone, and the fracture type showed typical ductile fracture.

Modelling Loans to Non-Financial Corporations in the Eurozone: A Long-Memory Approach

This paper uses fractional integration and cointegration methods to analyze the long-run relationship between loans to non-financial corporations, real gross domestic product, real gross fixed capital formation, the cost of borrowing differential between long- and short-term rates, and a proxy for the cost of debt, securities, and equity issuance. The analysis includes four Eurozone countries, namely Germany, France, Italy, and Spain, and spans the most recent decades. More precisely, fractional integration and cointegration models are estimated to investigate the persistence of the series as well as their long-run relationships and short-run dynamics using both unrestricted and restricted specifications. The univariate results are heterogeneous, the highest degrees of integration being found in the case of loans to non-financial corporations, whilst the multivariate ones provide evidence of a single fractional cointegration vector as well as of a lower adjustment speed to the long-run equilibrium compared to previous studies in all four countries. Moreover, both the short- and long-run response of loans to exogenous shocks to real gross domestic product and the cost of borrowing differentials differs across countries because of country-specific factors.

Disparities in precipitation effects on PM2.5 mass concentrations and chemical compositions: Insights from online monitoring data in Chengdu

Precipitation plays a pivotal role in wet deposition, significantly affecting aerosol purification. The efficacy of precipitation in removing aerosols depends on its type and the characteristics of the particulates involved. However, further research is necessary to fully understand how precipitation impacts PM2.5 components. This study utilized high-temporal-resolution data on PM2.5, its components and meteorological factors to examine varying responses influenced by precipitation intensity and duration. The findings indicate that increased rainfall intensity and duration enhance PM2.5 and its constituents removal efficiency. Specifically, longer precipitation periods significantly improve PM2.5 purification, especially with drizzle and light rain. Moreover, there is a direct correlation between pre-precipitation PM2.5 levels and its scavenging rates, with drizzle potentially exacerbating PM2.5 pollution under cleaner conditions (≤ 35 µg/m3). Seasonally, the efficacy of removing PM2.5 components varies notably in response to drizzle and light rain. In spring, higher PM2.5 levels after drizzle were primarily due to increased organic carbon concentrations favored by higher relative humidity and lower pH conditions compared to other seasons, conducive to secondary organic aerosol production. Lower wind speeds and higher temperatures further contribute to water-soluble organic carbon accumulation. Daytime and nighttime precipitation exerted differing influences on PM2.5 components, particularly in spring where daytime drizzle and light rain significantly increased PM2.5 and its constituents, notably NO3-, potentially associated with phase distribution changes between gas and aerosol phases in low-temperature, high-RH conditions compared to nighttime. These results propose a dual-impact mechanism of precipitation on PM2.5 and provide scientific basis for designing effective control strategies.

Raw bioelectrical data and physical performance in track and field athletes: Are there differences between the sexes in the relationship?

ObjectivesThe study aimed to investigate the relationship between raw bioelectrical data and physical performance in track and field athletes. Specifically, the objectives were to determine: 1) whether a regional bioelectrical impedance approach provides additional insights compared to whole-body analysis, 2) the reliability of the Levi Muscle Index (LMI) in this context, and 3) whether there are differences in these relationships between male and female athletes. DesignThis study utilized a cross-sectional design involving thirty-one female athletes (mean age 21.4 ± 3.8 years) and thirty male athletes (mean age 21.1 ± 2.6 years) from track and field. On a single day, participants underwent whole-body and regional bioelectrical impedance assessments focusing on the lower limbs, alongside strength and speed performance tests. ResultsThe study found no significant differences in the relationship between whole-body versus regional bioelectrical impedance and performance tests. Resistance (R) demonstrated an inverse correlation, while phase angle (PhA) and Levi Muscle Index (LMI) showed direct correlations with most performance variables in track and field athletes. Significant differences were observed between male and female athletes across all parameters, with male athletes exhibiting superior performance, higher PhA and LMI values, and stronger correlation coefficients compared to females. ConclusionsIn summary, this study highlights the intricate relationship between body composition and physical performance in athletes. It underscores the importance of considering sex differences and the reliability of raw bioelectrical data, whether obtained through regional or whole-body approaches, in assessing athletic performance.

Spatio-Temporal Variability of Algal Bloom in the Caspian Sea

Seasonal, interannual variability and spatial distribution of algal bloom in the North, Middle and South Caspian Sea has been investigated on the basis of Aqua MODIS chlorophyll-a (Chl-a) concentration data. Multi-year data demonstrate that over the two past decades Chl-a concentration has increased only in the North Caspian where the main rivers Volga and Ural enter the sea. In the Middle and South Caspian, it has shown weak negative linear trends. Special attention is paid to anomalous phytoplankton bloom, first of all cyanobacteria, in the South Caspian. Over 24 years of satellite observation, 1999-2022, abnormally intense phytoplankton bloom has been detected 8 times. Till present, it remains an open question what causes such outbreaks of intense algal bloom in the South Caspian. Generally, the literature and our studies suggest a variety of possible drivers of algal bloom, such as high sea surface and air temperature, low wind speed, high Chl-a concentration in periods preceding the development of phytoplankton bloom, atmospheric precipitation, and even dust storms. However, for the South Caspian we have found no clear correlation with any of these factors. Satellite monitoring of intense blooms, especially cyanobacteria, is of vital importance because cyanobacteria can produce potent toxins that can cause negative consequences for wildlife, ecosystems and even affect human health.

An energy management strategy based on dynamic programming for fuel cell hybrid trucks in ports

The deterioration of environment and the proposal of carbon neutrality are causing the transformation of port freight transportation. Fuel cell hybrid trucks (FCHTs) may be a promising solution for port logistic with the characteristics of low speed, heavy duty and frequent start-stops. How to achieve efficient energy management for FCHTs in ports is a key issue, which is still in the initial stage. The objective of this study is to investigate the effects of dynamic programming (DP) strategy on energy management of FCHTs. With the intention of calculating power demands, the FCHT structure and the models of each component are established. In the DP method, the state of charge (SOC) of the battery, the power supplied by the battery, and hydrogen fuel consumption are regarded as the state variable, the decision variable, and the objective function, respectively. The simulation results under two different typical working conditions in ports show that the proposed DP outperforms existing genetic algorithm (GA) and rule-based strategy for reducing hydrogen fuel consumption by over 10%. Moreover, a set of instances among several FCHTs with different parameters and conditions suggest different influences of key feature parameters on hydrogen fuel consumption and SOC. Nearly 50% cost reduction of the FCHT in the "quay crane-yard " (QCY) cycle compared with diesel trucks at the current price indicates wide application prospect of FCHTs. At last, the results under different conditions reconfirm that DP is an excellent strategy to tackle energy management of FCHTs in ports with frequent start-stops and heavy-load scenarios.

QRNet: Query-based reparameterization net for real-time detection of power adapter surface defects

In industrial production, automated surface defect detection holds paramount importance. While current techniques can handle complex background power adapter surface defect detection with high precision, they have many parameters, low speed, slow convergence, and complex post-processing (such as non-maximum suppression). To this end, this study aims to develop a more efficient and effective method for surface defect detection. The primary objective of this research is to enhance the speed of detection without sacrificing accuracy. This paper designs the Separable-reparam Feature Module (SFM), which is based on depth-wise convolution, to fuse multi-branch features through reparameterization techniques. SFM has low parameters and excels in feature extraction without increasing the model’s Memory Access Cost (MAC). SFM combines cross-stage fusion to construct the backbone, enabling the extraction of multi-scale features. Following the standard query decoder architecture, a QRNet was built to learn the query set of objects, and predict the surface defect set for power adapter. Additionally, a novel two-stage mixed-supervised transfer-learning approach is proposed to expedite the convergence process. Experimental results on the power adapter defect dataset demonstrate QRNet’s remarkable performance. It achieved a mean average precision (mAP) of 98.94 % with just 0.841 M parameters and a latency of 5.72 ms. In conclusion, QRNet represents an advancement in surface defect detection, offering a balance between accuracy and efficiency.

Numerical and Experimental Investigation of the Aerodynamic for the IceWind Blades VAWT

The main aim of the present work is the numerical and experimental investigation carried out in, for the IceWind blade type with two heights (Model 1=250 mm) and (Model 2=125 mm). In this study a computational fluid dynamic CFD is used to simulate the aerodynamic characteristics modelled medals at 10 m/s. The finite volume method and SST (k-ω) turbulent model were used in this simulation. In the experimental part the models are manufactured by three dimensions printing machine (3D printing) using Polylactic acid (PLA), and the experimental work was implemented by using low speed wind tunnel that is available at University of Baghdad/College of Engineering/Mechanical Engineering Department/Fluid Mechanics Laboratory. The finding results from the numerical simulation show that the maximum static pressure at (Model 1) was 69.39 (pa) and the maximum velocity was 13.5 (m/s). For (Model 2) it was 62.58 (pa) and the maximum velocity was 12.69 (m/s). The minimum static pressure at (Model 1) was -66.69 (pa) and the minimum velocity was 1.04 (m/s). For (Model 2) it was -47.94 (pa) and the minimum velocity was 0.98 (m/s). The experimental results showed that (Model 1) give high performance in comparison with (Model 2) , because rotational speed 610 RPM and the power coefficient was 0.0688 also the tip speed ratio was 0.4533, when (Model 2) give rotational velocity were 265 RPM and the power coefficient was 0.03551 also the tip speed ratio was 0.2601.

The effect of plyometric training (hurddle jumps), body weight training (lunges) and speed on increasing leg muscle explosive power of futsal players: a factorial experimental design

Futsal games have high intensity and dynamics that require good skills and physical conditions, one of which is leg muscle explosiveness. By doing plyometric training (hurddle jump), body-weight training (lunges), and paying attention to explosive power factors including speed as a group determinant is believed to affect the explosive power of the player's leg muscles. However, despite recognizing the importance of both training methods in improving leg muscle explosive power, there is still a lack of a thorough understanding of their combined effect on players' leg muscle explosive power during futsal play. This study aims to analyze the differences in the effect of the intervention groups of plyometric training methods and body weight training by considering the level of running speed on explosive power results. Training groups include plyometric training groups and body weight training groups, while speed is categorized as high or low. Using an experimental approach with a 2 x 2 factorial design, this study randomly selected 20 players aged 17.1 ± 0.768 years. Training was conducted in three sessions per week for approximately six weeks. Training focused on fast/explosive movements. Speed data was collected using the 30m acceleration test and the leg muscle explosiveness standing broad jump test. The data were then statistically analyzed using a two-way ANOVA at the 0.05 level of significance. The results showed that both training methods can benefit individuals with high speed (P&lt;0.05). However, leg muscle explosive power training with plyometric exercise was more effective on individuals with high speed (P&lt;0.05). As for those with low speed, plyometric exercise can provide better results (P&lt;0.05). These findings provide valuable insights for futsal coaches and instructors in designing customized training programs to improve leg muscle explosiveness. Keywords: Plyometric, Body Weight, Speed, Power

An accelerated sequential function specification method based on LM gradient for transient inverse heat conduction problem

The sequential function specification method (SFSM) and the Levenberg-Marquardt method (LM) are two typical methods for inverse heat conduction problems (IHCP). However, these two methods have poor convergence and low convergence speed. Therefore, the combination of LM with SFSM is depended on to propose a modified Sequential Levenberg-Marquardt gradient method (SLM). The computation results of three shapes of heat fluxes with noise show the SLM is averagely improved over 16.3% more than SFSM in computation accuracy, but equally reduced over 39.9% less than in computation time. On other hand, when the emphasis is on the effect of the Aitken acceleration method, Tikhonov regularization and polynomial order on SLM, a neural network prediction model of the root mean square error is trained by regularization factor, polynomial order and the number of future time steps. Subsequently, the genetic algorithm optimization method is proposed for the minimum root mean square error so that it can improve the computation accuracy and efficiency of IHCP to the maximum extent. Finally, Second-order polynomial order and small order-of-magnitude regularization factor are highly recommended for parameter selection with multiple choices. The ASLM only needs to determine the optimal number of future time steps.

Ab initio simulation of the dynamic shock response of single crystal and lightweight multicomponent alloy

The dynamic response of shock wave impact on single crystal aluminium and lightweight multicomponent alloy Al-Cu-Li-Mg is simulated by using the combination of Ab initio Molecular Dynamics (AIMD) and Multi-Scale Shock Technique (MSST), with the analysis carried out at the atomic/electronic levels. The simulation is verified by comparing the particle velocity of single crystal obtained in this work with the data in literature. The shock compression process not only involves the migration of atoms, but also is related to electronic transition. Two stages could be found in the shock compression process: oscillatory compression of the crystal cell and oscillatory migration of the atoms. The crystal structure of the multicomponent alloy could be disordered even at low shock speed, due to the difference in the ability to migrate between different kinds of atoms. As the sample is shock-compressed, the contribution proportion of crystal orbitals shows a sharp decrease for D orbital, while it increases significantly for S orbital and P orbital. The electron structure shows a quicker response to the shock wave compression process than the crystal structure. The orbital contribution from P orbital of the crystal is mainly due to the P orbital of Al atoms, while the orbital contribution from D orbital of the crystal is mainly due to the D orbital of Cu atoms. Total Density of States (TDOS) is mainly contributed by the Projected Density of State (PDOS) of Cu atoms in the occupied state of energy levels, while it is close to the PDOS of Al atoms in the non-occupied state of energy levels.

Experimental study on knock suppression by direct water injection and direct ammonia-water injection based on low-flow injector under high load

Under the appropriate injection strategies, both direct water injection and direct ammonia-water injection can effectively suppress the knock, but the effect of the knock suppression is slightly different. In this paper, water and ammonia-water were respectively injected directly into the cylinder of a high performance port gasoline injection engine by modified low-flow direct injectors. The effects of direct injection timing and injection ratio on knock, combustion and emission were investigated. Both water and ammonia-water can effectively suppress knock in SI mode. Compared to water, ammonia-water exhibits a more prominent inhibitory effect on knock at lower DI ratios. However, when the ratio was further increased, the difference between the effects of ammonia-water and water on the inhibition of knockdown became less pronounced. Water and ammonia-water DI affect the knock through different mechanisms due to their unique chemical properties. While water predominantly influences the later combustion phases due to its rapid vaporization and high specific heat capacity. Ammonia-water primarily impacts the early combustion phase because of its complex combustion process and lower laminar flame speed.

Boosting NIR Laser Marking Efficiency of a Transparent Epoxy Using a Layered Double Hydroxide.

Efficient near-infrared (NIR) laser marking on transparent polymers like polypropylene, epoxy, and polyethylene has posed a big challenge due to their lack of absorption in the NIR. Currently, inorganic additives are used to improve NIR laser marking efficiency, but they come with issues such as toxicity, high loading requirement, adverse effects on color/opaqueness, and the need for low laser head speeds. Herein, we report a new strategy of incorporating a food-grade, Mg2Al-CO3 LDH as a boosting coadditive alongside the commercial NIR laser marking additive (Iriotech 8815) in an epoxy system. Our findings demonstrate that the incorporation of Mg2Al-CO3 LDH can significantly increase both the darkness and contrast of marking even at high laser head speed (5000 mm/s), while minimizing surface damage. Notably, by replacing 95% of Iriotech 8815 with Mg2Al-CO3 LDH, an epoxy plate can exhibit high transparency, while producing dark, sharply defined markings with excellent readable QR code markings at high laser speeds. This result offers a promising solution for enhancing high-speed NIR laser marking on transparent polymers with additional advantages of lower toxicity and cost and with minimal optical interference from high additive loadings.

Adaptive unified gas-kinetic scheme for diatomic gases with rotational and vibrational nonequilibrium

Multiscale nonequilibrium physics at large variations of local Knudsen number are encountered in applications of aerospace engineering and micro-electro-mechanical systems, such as high-speed flying vehicles and low pressure of the encapsulation. An accurate description of flow physics in all flow regimes within a single computation requires a genuinely multiscale method. The adaptive unified gas-kinetic scheme (AUGKS) is developed for such multiscale flow simulation. The AUGKS applies discretized velocity space to accurately capture the non-equilibrium physics in the multiscale UGKS, and adaptively employs continuous distribution functions following Chapman–Enskog expansion to efficiently recover near-equilibrium flow region in GKS. The UGKS and GKS are dynamically connected at the cell interface through the fluxes from the discretized and continuous gas distribution functions, which avoids any buffer zone between them. In this study, the AUGKS with rotation and vibration non-equilibrium is developed based on a multiple temperature relaxation model. The real gas effect in different flow regimes has been properly captured. To capture aerodynamic heating accurately, the heat flux modifications from the rotation and vibration modes are also included in the current scheme. Unstructured discrete particle velocity space is adopted to further improve the computational performance of the AUGKS. Numerical tests, including Sod tube, normal shock structure, high-speed flow around the two-dimensional cylinder and three-dimensional sphere and space vehicles, and an unsteady nozzle plume flow from the continuum flow to the background vacuum, have been conducted to validate the current scheme. In comparison with the original UGKS, the current scheme speeds up the computation, reduces the memory requirement, and maintains the equivalent accuracy for multiscale flow simulation, which provides an effective tool for nonequilibrium flow simulations, especially for the flows at low and medium speed.

Dynamics and mitigation strategies of knock in hydrogen-fueled internal combustion engines

In the context of utilizing hydrogen as a fuel for internal combustion engines, it is crucial to address its tendency to induce knock more readily under certain conditions compared to gasoline. Knock not only reduces fuel efficiency but also has the potential to inflict detrimental effects on engine components. It is generally believed that knock is primarily caused by the spontaneous combustion of the end-gas mixture. Current research focuses on the frequency, intensity, and statistical characteristics of knock signals.This study aims to introduce two prevalent and effective methods for mitigating knock: increasing the Exhaust Gas Recirculation (EGR) ratio and water injection into the engine. Experimental observations suggest that at low rotational speeds (n=900 rpm), the amplitude spectra of knock induced by hydrogen and gasoline show similarities. However, at higher speeds (n&gt;3000 rpm), the amplitude of hydrogen-induced knock not only exhibits a greater number of peak values but also intensifies in strength. Notably, the efficacy of increasing the EGR ratio diminishes at high speeds, potentially due to the propensity of methane to also cause knock under high-temperature conditions. In contrast, water injection, while generally effective, may adversely impact the lifespan of engine components.In summary, effective suppression of knock in hydrogen-fueled internal combustion engines is vital for accelerating the adoption of hydrogen in the power sector and making significant contributions to environmental conservation. This paper aims to delve into the analysis of these methods effectiveness and proposes directions for future research.

Computerized assessment of handwriting in de novo Parkinson's disease: A kinematic study

IntroductionDysgraphia, a recognized PD motor symptom, lacks effective clinical assessment. Current evaluation relies on motor assessment scales.Computational methods introduced over the past decade offer an objective dysgraphia assessment, considering size, duration, speed, and handwriting fluency. Objective evaluation of dysgraphia may be of help for early diagnosis of PD. ObjectiveComputerized assessment of dysgraphia in de novo PD patients and its correlation with clinical scales. MethodsWe evaluated 38 recently diagnosed, premedication PD patients and age-matched controls without neurological disorders. Participants wrote “La casa de Pamplona es bonita” three times on paper and once on a Wacom tablet under the paper, totaling four phrases. Writing segments of 5–10 s were analyzed. The Wacom tablet captured kinematic data, including mean velocity, mean acceleration, and pen pressure. Data were saved in.svc format and analyzed using specialized software developed by Tecnocampus Mataró. Standard clinical practice data, Hoehn & Yahr staging, and UPDRS scales were used for evaluation. ResultsSignificant kinematic differences existed; patients had lower mean speed (27 ± 12 vs. 48 ± 18, p < 0.0001) and mean acceleration (7.2 ± 3.9 vs. 15.01 ± 7, p < 0.0001) than controls. Mean speed and mean acceleration correlated significantly with UPDRS III scores (speed: r = −0.52, p < 0.0007; acceleration: r = 0.60, p < 0.0001), indicating kinematic parameters' potential in PD evaluation. ConclusionsDysgraphia is identifiable in PD patients, even de novo, indicating an early symptom and correlates with clinical scales, offering potential for objective PD patient evaluation.