Low Speed Research Articles

Resolution Dependence of Extreme Wind Speed Projections in the Great Lakes Region

Abstract The effect of anthropogenic climate change on extreme near-surface wind speeds is uncertain. Observed trends are weak and difficult to disentangle from internal variability, and model projections disagree on the sign and magnitude of trends. Standard coarse-resolution climate models represent the fine structures of relevant physical phenomena such as extratropical cyclones (ETCs), upper-level jet streaks, surface energy fluxes, and land surface variability less skillfully than their high-resolution counterparts. Here, we use simulations with the NCAR Community Earth System Model with both uniform (110 km) resolution and the variable-resolution configuration (VR-CESM-SONT, from 110 to 7 km) to study the effect of refined spatial resolution on projections of extreme strong and weak wind speeds in the Great Lakes region under end-of-century RCP8.5 forcing. The variable-resolution configuration projects strengthening of strong-wind events in the refined region with the opposite occurring in the uniform-resolution simulation. The two configurations provide consistent changes to synoptic-scale circulations associated with high-wind events. However, only the variable-resolution configuration projects weaker static stability, enhanced turbulent vertical mixing, and consequentially enhanced surface wind speeds because boundary layer dynamics are better captured in the refined region. Both models project increased frequency of extreme weak winds, though only VR-CESM-SONT resolves the cold-season inversions and summertime high temperatures associated with stagnant wind events. The identifiable mechanism of the changes to strong winds in VR-CESM-SONT provides confidence in its projections and demonstrates the value of enhanced spatial resolution for the study of extreme winds under climate change. Significance Statement In this study, we compare climate change projections of high and low extreme wind speeds in the Great Lakes region between a standard coarse-resolution simulation and a high-resolution simulation performed using the same climate model. The fine-resolution simulation projects strengthening high wind speeds, opposite to the coarse-resolution simulation. Both project increasing frequency of extreme weak winds, but the human-health-related impacts of stagnant winds are only captured at fine resolution. The changes in the coarse-resolution simulation are explained by changes to large-scale circulation, while the fine-resolution changes are linked to local processes the coarse model does not resolve. This helps explain the diverging projections of strong winds and gives greater credibility to the fine-resolution simulation.

Оценка нестабильности последовательных впрыскиваний топливной аппаратуры дизелей

The issues of uneven cyclic feed in sequential injections by diesel fuel equipment are considered, which is directly related to solving the problem of ensuring the quality of operation of engines of various types and purposes when operating at low loads and rotational speeds. The special importance of solving these problems from the standpoint of ensuring fuel efficiency, environmental pollution, solving issues of engine reliability and improving their operational properties was noted. The features of the formation of residual fuel pressure in the high-pressure pipeline are revealed. The periodic fluctuations of the cyclic feed and injection parameters from cycle to cycle are estimated. A study of possible options for the operation of fuel equipment in low fuel supply modes has been carried out. Based on the analysis, a criterion for evaluating the instability of successive injection cycles for diesel fuel equipment during its operation in various modes has been introduced. By studying numerical examples, the conditions of unstable fuel supply processes in successive injections of various characteristic modes are determined. The criterion determines the quality of the fuel equipment of marine diesel engines and diesel generators in terms of ensuring a minimum stable idle speed and the possibility of ensuring stable reduced fuel supplies. The variability of fuel supply processes in sequential feeds is the cause of increased exchange processes of electric power flow during parallel operation of diesel alternators and reduces the performance characteristics of diesels for various purposes when operating in partial modes. In the process of carrying out development work, scientific research and during the refinement of diesels, the instability criterion allows us to assess the quality of the fuel equipment precisely in partial modes. This is of particular importance for diesel engines of fishing vessels operating for a long time at shared loading modes and low idle speeds, as well as for engines of the tugboat fleet and auxiliary diesel generator sets of all types of facilities used.

Evaluating the Microhardness Profiles in Friction Stir Welding of Dissimilar Alloys

Abstract: Friction stir Welding (FSW) advancement is used generally in the utilization of present-day flying and vehicle industry for predominant fundamental mentioning. Such a joining technique is displayed to avoid serious twists and the made excess weights are exhibited as low when it is stood out from the traditional welding structure. In this research, focus on to identify the parameters that will provide the dissimiliar alloys of aluminium AA6061 and AA8011 with good microhardness properties. From the current study microhardness strength of dissimiliar alloys of aluminium varies with the rpm, feed rate and shoulder diameter of the tool. At 2000 rpm and 15mm/min welding speed strength of joints is low and at high rpm 2400 and welding speed 20mm/min micro hardness strength is always low but at a rotation speed of 2200 rpm and welding speed 20 mm/min maximum strength of the weld joint . Hence at high rotational speed rise in the temperature occurs and cause dissolution of precipitates which lowers the hardness and at low rotational speed less heat generation at the tool workpiece interface causing less refinement of grains which lower the hardness value. During tensile strength test fracture and cracks occurs at weld center line.

Task Scheduling by Hybrid Metaheuristic Approach in Cloud Environment

Abstract: Recent advancements in hardware, virtualization technology, distributed computing, and service delivery over the Internet have led to the formation of cloud computing. In a distributed computing platform, the scheduling of task workflow is a well-known NP-hard problem. This becomes more complex and challenging if the virtualized clusters execute a large number of tasks in a cloud computing platform. From low-level execution tasks in multiple processors to high-level execution tasks, many heuristics have been proposed. This chapter deals with the proposed min-min algorithm, max-min algorithm, PSO, and TS. The max-min and min-min algorithms estimate the execution time and overall completion time of all the tasks Then assign the tasks on better suitable resource. PSO is simple and effective in a wide range of applications with low computational cost and fast speed. TS approach is one of the popular local search techniques based on neighborhood search algorithm. TS can be directly applied to any kind of virtual optimization problem.

Изотермическое прессование в конической матрице релаксирующего материала

The relations for calculating the deformation mode and force conditions of isothermal extrusion of blanks made of high-strength metallic alloys are proposed. Under isothermal deformation, the material is hardened and softened, which is associated with the manifestation of the viscous properties of the material (creep). In this regard, the state of viscoplasticity is taken on. The deformation state is accompanied by stress relaxation, which is greater the lower the speed (longer duration) of the operation. Based on the mechanics of deformation, the dependence of moulding conditions (deformation, force, damage to the work material) is expressed by analytical relations. The power balance of activity of forces results in a pressure estimation for isothermal exposure. In this case, a discontinuous field of path velocities is used, which consists of a block of deformations and rigid blocks. The blocks are separated by slip surfaces. Deformations occur in the deformation block and on slip surfaces. Since pressing leads to the occurrence of micro-damages, the damage rate of the coating material was estimated. In this case, the criteria of fracture kinetics are used: energy and deformation equations. The damage rate of the material depends on the speed and degree of deformation, or solely on the degree of deformation. For a number of materials, reducing the speed helps to reduce damage and, consequently, the possibility of increasing the degree of shaping of the primary blank. The relations for stiffness analysis of the stress pattern are given, on which the damage also depends. Calculations of the pressure and damage of the material under compaction for blanks made of titanium and high-strength aluminum alloys have been performed. It is shown that at low operation speeds on the appropriate hydraulic forging equipment, the exposure pressure decreases significantly. The aluminum alloy damaging is also reduced, and for titanium it depends only on the degree of forming.

Stepless Transmission Optimization for Green Micromobility

Small, electrified vehicles are becoming possible for urban environmental mobility due to their environmental performance, including zero-emission driving. Vehicles of this type use electric motors as sources of mechanical energy. Today, two types of transmission are most used in electrical micromobility vehicles (skateboards, scooters, tricycles, quadricycles, mopeds, motorcycles, go-karts, etc.): chain transmission and belt transmission. This transmission types provides a constant gear ratio that can only compromise between the maximum speed and the starting torque values, thus reducing the usage efficiency of the engine. This reduces vehicle manufacturers’ choice of less powerful drive and control elements, as well as balancing performance and efficiency at low and high speeds as well as on terrain.A novel design of a continuously variable transmission (CVT) for an electric go-kart is presented in this paper. The CVT consists of an inertial driving pulley mounted on an electric motor shaft, a timing V-belt, a gear wheel on the drive axle and 2 pressure rolls, which are moved by a servo motor for tensioning the V-belt. Gear ratio of a transmission can change seamlessly in the range of 1.5 - 2.2. The CVT has been tested under real conditions. The top speed of the electric go-kart with the given CVT and motor power 24.7 kW is 133km/h; time to accelerate to the top speed is 25 s. Total efficiency of the transmission (motor shaft, CVT, drive axle and wheels) is 65-72 % now, but there exist a lot of possibilities to improve it in the future. The conditions under which the novel CVT has an advantage over belt and chain transmissions with constant gear ratios have been studied. The developed mathematical model, the method for determination its constants, the algorithm for numerical calculations and the optimization criterion makes it possible to determine the optimal gear ratio for a vehicle with various CVT (not only belt) at any point in time in different racing modes. The model has been proved experimentally during acceleration and deceleration tests of the go-kart; it describes precisely the motion of the go-kart within the speed measurement error.The developed solution is applicable in urban micromobility. An optimized and stable transmission system focused on energy efficiency, resource saving, using less powerful drive and zero-emission.

Analysis of Shield Tunneling Parameters and Research on Prediction Model of Tunneling Excavation Speed in Volcanic Ash Strata of Jakarta–Bandung High-Speed Railway Project

Insufficient investigations have been conducted on the analysis of shield tunneling parameters and the prediction of the tunneling excavation speed in formations composed of volcanic ash strata. To address this issue, we employ a comprehensive approach utilizing literature research, mathematical statistics, and other methodologies, centered on the analysis of the No. 1 Tunnel of the Jakarta–Bandung High-Speed Railway. Our focus is on examining the evolution patterns and inter-relationships of shield tunneling parameters within volcanic ash strata. Subsequently, we propose an optimized strategy for these tunneling parameters. By employing six machine-learning algorithms to construct prediction models, we compare and analyze their performance in predicting the tunneling excavation speed. The results indicate a positive correlation between slurry pressure and tunnel depth in volcanic ash strata, suggesting that the grouting pressure should exceed the slurry pressure by approximately 0.22 MPa. In the composite stratum of “volcanic ash debris + round gravel”, the cutter torque exhibits a strong negative correlation with the total thrust (−0.77). Due to tool wear and ground resistance, the excavation speed and cutter speed are weakly negatively correlated. Compared to other strata, shield tunneling in volcanic ash strata exhibits larger grouting pressure fluctuations, slower tunneling excavation speed, greater total thrust, higher cutter torque, and lower cutter speed. Regarding shield tunneling excavation speed prediction, the ranking of the algorithm performance is RF > DNN > ANN > BPNN > MNR > SVM, with RF achieving a decision coefficient of 0.829. The RF model is well-suited for predicting the shield structure tunneling excavation speed.

Perceived built environments correlated to route choice for healthy leisure walking

ABSTRACT This study aimed to identify the environmental factors of pedestrians’ preferred route and examine which factors are related to the choice of a healthy route. This study set the shortest and healthy routes in Ayanggyo neighborhood in Daegu Metropolitan City, South Korea. A healthy route is longer than the shortest route but has rich greenery and low traffic. A survey of 203 respondents was conducted from October 12 to 8 November 2022. This study used a logistic regression model with a walking route choice as the dependent variable. Results showed that 65% of participants chose a healthy route. People who considered low noise levels, presence of greenery and waterfront areas, low traffic speed, and presence of traffic safety facilities as important were likelier to choose healthy routes. The results suggest that pleasant and safe routes and built environments can make people walk longer. The findings of this study provide evidence to urban planners and policymakers that the built environmental conditions play an important role in encouraging residents’ walking behavior. This can contribute to urban policies supporting citizens’ active and healthy walking.

New technology to address affected vs nonaffected arm contributions to ergometer performance in people poststroke

ABSTRACT Background When pedaling a coupled-crank arm ergometer, individuals with hemiplegia may experience nonparetic arm overcompensation, and paretic arm resistance, due to neuromechanical deficits. Technologies that foster independent limb contributions may increase the effectiveness of exercise for people poststroke. Objective Examine the speed during uncoupled pedaling with the Advanced Virtual Exercise Environment Device among individuals poststroke and non-impaired comparisons. Methods We recruited 2 groups:Poststroke and Comparison. Participants attended one lab session and performed peak speed tests and a graded exercise repeated for bilateral pedaling, unilateral (left, right). Results Thirty-one participants completed the protocol (16 women, 15 men). Poststroke participants pedaled slower during the bilateral speed test (64 ± 39 RPM, p < .001), and graded exercise, (54 ± 28 RPM, p < .001) versus comparisons (141 ± 19, 104 ± 12 RPM). Poststroke individuals had lower peak RPM during the unilateral speed test with their paretic arm (70 ± 46 RPM, p < .001) and graded exercise (58 ± 33 RPM, p < .001) compared to their unilateral speed test (130 ± 37 RPM) and graded exercise (108 ± 25 RPM) with their nonparetic arm. Comparisons did not differ between arms during speed tests and graded exercise. Poststroke participants demonstrated lower peak speed with their affected arm during the bilateral speed test (52 ± 42 RPM, p < .001) and graded exercise (49 ± 28 RPM, p = .008) compared to the same arm during unilateral speed (70 ± 46 RPM) and graded exercise (58 ± 33 RPM). Conclusions Poststroke participants pedaled faster with their affected arm unilaterally versus bilateral pedaling, suggesting interhemispheric interference that reduces the ability to recruit the paretic arm during bilateral exercise.

Oropharyngeal swallowing hydrodynamics of thin and mildly thick liquids in an anatomically accurate throat-epiglottis model

Understanding the mechanisms underlying dysphagia is crucial in devising effective, etiology-centered interventions. However, current clinical assessment and treatment of dysphagia are still more symptom-focused due to our limited understanding of the sophisticated symptom-etiology associations causing swallowing disorders. This study aimed to elucidate the mechanisms giving rise to penetration flows into the laryngeal vestibule that results in aspirations with varying symptoms. Methods: Anatomically accurate, transparent throat models were prepared with a 45° down flapped epiglottis to simulate the instant of laryngeal closure during swallowing. Fluid bolus dynamics were visualized with fluorescent dye from lateral, rear, front, and endoscopic directions to capture key hydrodynamic features leading to aspiration. Three influencing factors, fluid consistency, liquid dispensing site, and dispensing speed, were systemically evaluated on their roles in liquid aspirations. Results: Three aspiration mechanisms were identified, with liquid bolus entering the airway through (a) the interarytenoid notch (notch overflow), (b) cuneiform tubercle recesses (recess overflow), and (c) off-edge flow underneath the epiglottis (off-edge capillary flow). Of the three factors considered, liquid viscosity has the most significant impact on aspiration rate, followed by the liquid dispensing site and the dispensing speed. Water had one order of magnitude higher aspiration risks than 1% w/v methyl cellulose solution, a mildly thick liquid. Anterior dispensing had higher chances for aspiration than posterior oropharyngeal dispensing for both liquids and dispensing speeds considered. The effects of dispending speed varied. A lower speed increased aspiration for anterior-dispensed liquids due to increased off-edge capillary flows, while it significantly reduced aspiration for posterior-dispensed liquids due to reduced notch overflows. Visualizing swallowing hydrodynamics from multiple orientations facilitates detailed site-specific inspections of aspiration mechanisms.

Cross-Cultural Adaptation and Validation of the Portuguese Version of the SARC-F in Community-Dwelling Older Adults

(1) Background: The goal of this study was to analyze the reliability and validity of the Portuguese version of the SARC-F in older adults. (2) Methods: A total of 100 participants (77.1 ± 7.36 years, 73% women) were included in the study. In a first phase, the Portuguese SARC-F was adapted following the standardized forward–backward translation procedure, and internal consistency as well as inter-rater and test–retest reliability of the Portuguese SARC-F were analyzed. Secondly, clinical validation was evaluated by comparing the SARC-F total score with five operational definitions of sarcopenia and with other sarcopenia-related measurements. Discriminant validity, with respect to low muscle mass and strength and physical function were analyzed. (3) Results: The Portuguese SAR-F showed acceptable internal consistency (Cronbach α = 0.82), excellent inter-rater reliability (total score), and substantial to excellent test–retest reliability (ICC = 0.891 for the total score). Specificity ranged from 72.5% (FNIH) to 73.4 (IGWS), and negative predictive values went from 91.8% (EWGSOP1) to 97.3% (FNIH), but low sensitivity and positive predictive value were observed. The Portuguese SARC-F showed a moderate ability to discriminate people with low muscle strength (AUC = 0.78) and gait speed (AUC = 0.89). (4) Conclusions: The Portuguese SARC-F is a valid and reliable tool for ruling out sarcopenia in community-dwelling older adults and can discriminate between people with low handgrip strength and gait speed.

Detection of tetanus toxoid with iron magnetic nanobioprobe

Diagnosis of diseases with low facilities, speed, accuracy and sensitivity is an important matter in treatment. Bioprobes based on iron oxide nanoparticles are a good candidate for early detection of deadly and infectious diseases such as tetanus due to their high reactivity, biocompatibility, low production cost and sample separation under a magnetic field. In this study, silane groups were coated on surface of iron oxide nanoparticles using tetraethoxysilane (TEOS) hydrolysis. Also, NH2 groups were generated on the surface of silanized nanoparticles using 3-aminopropyl triethoxy silane (APTES). Antibody was immobilized on the surface of silanized nanoparticles using TCT trichlorothriazine as activator. Silanization and stabilized antibody were investigated by using of FT-IR, EDX, VSM, SRB technique. UV/vis spectroscopy, fluorescence, agglutination test and ELISA were used for biosensor performance and specificity. The results of FT-IR spectroscopy showed that Si–O–Si and Si-O-Fe bonds and TCT chlorine and amine groups of tetanus anti-toxoid antibodies were formed on the surface of iron oxide nanoparticles. The presence of Si, N and C elements in EDX analysis confirms the silanization of iron oxide nanoparticles. VSM results showed that the amount of magnetic nanoparticles after conjugation is sufficient for biological applications. Antibody stabilization on nanoparticles increased the adsorption intensity in the uv/vis spectrometer. The fluorescence intensity of nano bioprobe increased in the presence of 10 ng ml−1. Nanobio probes were observed as agglomerates in the presence of tetanus toxoid antigen. The presence of tetanus antigen caused the formation of antigen-nanobioprobe antigen complex. Identification of this complex by HRP-bound antibody confirmed the specificity of nanobioprobe. Tetanus magnetic nanobioprobe with a diagnostic limit of 10 ng ml−1 of tetanus antigen in a short time can be a good tool in LOC devices and microfluidic chips.

Adaptive Mobility-Based IoT LoRa Clustering Communication Scheme

Long Range (LoRa) as a low-power wide-area technology is distinguished by its robust long-distance communications tailored for Internet of Things (IoT) networks. Because LoRa was primarily designed for stationary devices, when applied to mobile devices, they become susceptible to frequent channel attenuation. Such a condition can result in packet loss, higher energy consumption, and extended transmission times. To address these inherent challenges posed by mobility, we propose an adaptive mobility-based IoT LoRa clustering communication (AMILCC) scheme, which employs the 2D random waypoint mobility model, strategically partitions the network into optimal spreading factor (SF) regions, and incorporates an adaptive clustering approach. The AMILCC scheme is bolstered by a hybrid adaptive data rate (HADR) mechanism categorized into two approaches, namely intra-SF and inter-SF region HADRs, derived from the standard network-based ADR mechanism for stationary devices, to ensure efficient resource allocation for mobile IoT LoRa devices. Evaluation results show that, based on simulations at low mobility speeds of up to 5 m/s, AMILCC successfully maximizes the packet success ratio to the gateway (GW) by over 70%, reduces energy consumption by an average of 55.5%, and minimizes the end-to-end delay by 47.62%, outperforming stationary schemes. Consequently, AMILCC stands as a prime solution for mobile IoT LoRa networks by balancing the high packet success ratio (PSR) with reliability with energy efficiency.

An integrated three-dimensional aeromechanical analysis for the prediction of stresses on modern coaxial rotors

This paper presents the first application of an Integrated Three-Dimensional aeromechanical analysis—defined as the coupled solution of three-dimensional finite element-based structural dynamics with a three-dimensional Reynolds-Averaged Navier-Stokes-based fluid dynamics—to predict the stresses on a modern coaxial rotor. The coupling was carried out with the University of Maryland’s structural dynamic solver X3D and the U.S. Army’s CREATETM–AV Helios suite of fluid dynamic solvers. A modern four-bladed hingeless coaxial rotor model—inspired by the gross dimensions of the Sikorsky S-97 Raider but generic and open source otherwise—is developed as a demonstration test case. The new structural solver is driven by parallel and scalable solvers and advanced high performance computing. It is enabled by high-order three-dimensional brick finite elements unified with multibody dynamics, integrated aerodynamics, and a special 3D-to-1D fluid-structure interfaces refines the power of delta-coupling procedure while retaining the advantages of existing CFD mesh motion schemes. The analysis predicts the three-dimensional stresses on the rotor blades and hub, together with the deformations, airloads, and wake, in an integrated manner. Two flight conditions are studied: a low-speed flight at 37 knots and a high-speed flight at 150 knots. Interesting three-dimensional unsteady stress patterns are revealed all across the blade but particularly inboard of 50% rotor radius—patterns that change from flight to flight and have remained invisible until now—since they could neither be predicted nor measured in flight. The maximum axial stresses exhibited 3/rev variation at low speed, and 2/rev variation at high speed flight. The lower rotor carried higher oscillatory stress burden at low speed, whereas both the rotors shared the same stress burden at high speed flight. The key conclusion is that such analysis is now indeed possible, and the stress patterns they reveal provide deeper insights into the dynamics of advanced rotors, and these might provide a path toward mitigating them in the future.

#1874 Comparative analysis of rehabilitation outcomes in hospitalized hemodialysis vs. non-hemodialysis patients: a retrospective cohort study

Abstract Background and Aims The hospitalization rate of patients undergoing hemodialysis (HD) is high, due to complications related to renal failure and hemodialysis treatment. Therefore, it is crucial to provide rehabilitation for hospitalized HD patients to improve their activities of daily living (ADL) and physical functions, so as to enable them to be discharged home, resume outpatient dialysis, and avoid re-hospitalization. However, the effectiveness of rehabilitation to improve the ADL and physical functions may differ between hospitalized patients undergoing HD (HD patients) and hospitalized patients not undergoing HD (non-HD patients), depending on their pathological conditions and influence of the HD treatment. The aim of the present study was to compare the outcomes of rehabilitation between hospitalized HD patients and non-HD patients. Method This was a retrospective cohort study. The inclusion criteria were hospitalized patients who received rehabilitation between April 2017 and February 2023. The exclusion criteria were patients who discontinued rehabilitation, were transferred to other hospitals, or died during the rehabilitation period. Rehabilitation consisted of physical therapy and/or occupational therapy provided six times a week, for both hospitalized HD and non-HD patients. The rehabilitation program comprised balance training, aerobic exercises, resistance training, and ADL training to prepare the patients for discharge to their homes. We measured several outcomes in the study, including the daily duration of rehabilitation (min/day), length of hospital stay (days), Barthel index (BI), as the ADL index, at the time of admission and discharge, grip strength and isometric knee extension strength (IKES) as muscle strength indices, and the 10-meter walking speed, timed up and go test (TUG), and short physical performance battery (SPPB) as mobility function indices. For the statistical analysis, missing values were completed by using multiple imputation methods. The inverse probability weighting (IPTW) method was used to match the HD group and non-HD group to adjust for confounding factors. The outcomes between the groups were then compared using a generalized linear model analysis. All procedures in the present study were conducted with the approval of the ethics committee of Seirei Christopher University. Results Of 1002 patients who were registered for the study, 100 patients who discontinued rehabilitation, were transferred to other hospitals, or died were excluded, and the data of the remaining 902 patients (765 of the non-HD group and 137 of the HD group) were included in the analysis in this study. The results of the generalized linear model analysis revealed a lower daily duration of rehabilitation [43.3(0.6) vs. 38.8(1.2) min/day, p=0.0003] and longer length of hospital stay [48.5(0.5) vs. 58.1(2.3) days, p=0.0108] in the HD group. In addition, the 10-meter walking speed [0.75(0.02) vs. 0.66(0.03) m/s, p=0.003] and scores on the TUG [20.8(0.7) vs. 24.3(1.0) sec, p=0.0021] and SPPB [6.3(4.57) vs. 4.7(0.6) points, p=0.0415] at discharge were also significantly lower in the HD group as compared with the non-HD group. There was no difference in the ability for ADL or muscle strength at discharge between the two groups. Conclusion This study was the first to demonstrate a lower daily duration of rehabilitation and longer hospital stay in hospitalized HD patients. Furthermore, rehabilitation had a lower impact on the mobility indices in HD patients as compared with non-HD patients. Although there was no difference in the ability for ADL or muscle strength at discharge between the two groups, HD patients exhibited a significantly lower ability for mobility functions, including a lower gait speed and lower scores on the TUG, and SPPB assessments. Therefore, rehabilitation efforts in HD patients need to be improved by securing more time for inpatient rehabilitation and promoting mobility function improvement.

Electric vehicles as an emission mitigation option: expectations and reality

AbstractGlobally, the reliance on thermal power, constituting 67% of electricity generation, prompts questions for many countries regarding the viability of electric vehicles (EVs) for emission reduction in the transportation sector. This study comprehensively analyzes CO2 emissions in the small family car segment, considering engines powered by different energy sources. The analysis is coupled with Worldwide Harmonized Light Vehicle Test Procedure driving profiles, accounting for specific ambient temperature structures representative of densely populated areas in Türkiye. The constructed model incorporates the hourly temperature of the relevant cities and the hourly electricity production mix by considering the indirect emissions and comparing the ICEVs (Internal Combustion Engine Vehicles) and EVs in different time frames from 2015 to 2020. The resulting emissions from each vehicle type in each city and driving profile, along with the ratio of instances in which EVs exhibit higher emissions than ICEVs, are presented.The findings reveal the intricate interplay between vehicle type, climate conditions, and driving profiles. While the urban driving profile emerges as superior for EVs regarding CO2 reduction, offering a comfortable driving experience without range anxiety and mitigating local pollutants, it exhibits less significant carbon emission reductions at lower and higher speed profiles, particularly in cold climate conditions. EVs are not a silver bullet but a valuable technology for emissions reduction under specific conditions. Policymakers are urged to consider factors favoring EVs over ICEVs regarding CO2 emissions, such as driving profiles, time and climatic conditions when formulating investment policies and subsidies. Graphical abstract

Quay-to-quay mission with autonomous docking: a model-scale experimental validation

Transport of cargo by short-sea shipping is at the forefront of the European Union's transportation policy. It has the promise to alleviate congested land transport and decrease pollution [European Commission. 2021. Putting European transport on track for the future]. However, the shortage of qualified personnel might impede this solution. Autonomous sailing of ships could help, especially if the whole trip is automated. In this study a control system is designed that is capable of sailing a round-trip with a model-scale feeder vessel in Marin's Seakeeping and Manoeuvring Basin. The Guidance-Navigation-Control framework is used to sail this journey with attention given to smooth switching between the operational modes. A set of experiments is conducted to validate the controller and identify crucial parts in the operation. The experiments showed that the controlled vessel can sail a round-trip with different levels of waves and wind disturbances coming from different directions. Furthermore, the round-trip can be modified such that the approach angle to the quay changes and the ship still successfully docks at the quay. It was found that the approach to the quay is most difficult during transition from high to low speed, when the bow thrusters have yet to become effective, and a large change in course is needed. This can be circumvented by changing the trajectory to the quay to have a longer straight approach, or it can be corrected when the bow thrusters become active.

Gait Characteristics over the Six-minute Walk Test in Older Women of a Specific Portuguese Community: A Cross-Sectional Study.

There is limited research on the changes that can occur in the gait biomechanical parameters of older adults over long-distance walking. Thus, this study aimed to evaluate the gait characteristics of older women of a specific Portuguese community over the six-minute walk test (6MWT) along with gait spatial and temporal parameters and angular kinematics of the lower limb joints. Twenty-six older women voluntarily participated. Each woman performed the 6MWT, and during this, their spatial and temporal parameters were collected through plantar pressure data (100Hz) and angular kinematics through an inertial sensor system (100Hz). The 6MWT was divided into four intervals, and the Friedman test was used to compare them. The median age of the women was calculated, and the Mann-Whitney test was used to compare women above and below the median age value. An increase in gait speed, stance phase, and double stance phase along the intervals was observed, as well as larger angular displacements of the hip, knee, and ankle (p<0.05). Women below or above the median age value also yielded these behaviours. Gait speed, cadence, stride length, and step length were higher in women below the median age value, while stride and step duration were lower (p<0.05). Older women yielded changes in gait spatial and temporal parameters along the 6MWT, as well as larger angular displacements of the lower limb joints. Older women (compared to younger ones) yielded lower gait speed, cadence, stride length, and step length, higher stance and double stance phases, and shorter angular displacements of the lower limb joints.

Epidemiological characteristics of tuberculosis incidence and its macro-influence factors in Chinese mainland during 2014–2021

BackgroundTuberculosis (TB) remains a pressing public health issue, posing a significant threat to individuals' well-being and lives. This study delves into the TB incidence in Chinese mainland during 2014–2021, aiming to gain deeper insights into their epidemiological characteristics and explore macro-level factors to enhance control and prevention.MethodsTB incidence data in Chinese mainland from 2014 to 2021 were sourced from the National Notifiable Disease Reporting System (NNDRS). A two-stage distributed lag nonlinear model (DLNM) was constructed to evaluate the lag and non-linearity of daily average temperature (℃, Atemp), average relative humidity (%, ARH), average wind speed (m/s, AWS), sunshine duration (h, SD) and precipitation (mm, PRE) on the TB incidence. A spatial panel data model was used to assess the impact of demographic, medical and health resource, and economic factors on TB incidence.ResultsA total of 6,587,439 TB cases were reported in Chinese mainland during 2014–2021, with an average annual incidence rate of 59.17/100,000. The TB incidence decreased from 67.05/100,000 in 2014 to 46.40/100,000 in 2021, notably declining from 2018 to 2021 (APC = -8.87%, 95% CI: -11.97, -6.85%). TB incidence rates were higher among males, farmers, and individuals aged 65 years and older. Spatiotemporal analysis revealed a significant cluster in Xinjiang, Qinghai, and Xizang from March 2017 to June 2019 (RR = 3.94, P < 0.001). From 2014 to 2021, the proportion of etiologically confirmed cases increased from 31.31% to 56.98%, and the time interval from TB onset to diagnosis shortened from 26 days (IQR: 10–56 days) to 19 days (IQR: 7–44 days). Specific meteorological conditions, including low temperature (< 16.69℃), high relative humidity (> 71.73%), low sunshine duration (< 6.18 h) increased the risk of TB incidence, while extreme low wind speed (< 2.79 m/s) decreased the risk. The spatial Durbin model showed positive associations between TB incidence rates and sex ratio (β = 1.98), number of beds in medical and health institutions per 10,000 population (β = 0.90), and total health expenses (β = 0.55). There were negative associations between TB incidence rates and population (β = -1.14), population density (β = -0.19), urbanization rate (β = -0.62), number of medical and health institutions (β = -0.23), and number of health technicians per 10,000 population (β = -0.70).ConclusionsSignificant progress has been made in TB control and prevention in China, but challenges persist among some populations and areas. Varied relationships were observed between TB incidence and factors from meteorological, demographic, medical and health resource, and economic aspects. These findings underscore the importance of ongoing efforts to strengthen TB control and implement digital/intelligent surveillance for early risk detection and comprehensive interventions.Graphical

Novel Hybrid Mexican Axolotl Optimization with Fuzzy Logic for Maximum Power Point Tracker of Partially Shaded Photovoltaic Systems

Due to the nonlinear relation between the generated power and voltage of photovoltaic (PV) arrays, there is a need to stimulate PV arrays to operate at maximum possible power. Maximum power can be tracked using the maximum power point tracker (MPPT). Due to the presence of several peaks on the power–voltage (P–V) characteristics of the shaded PV array, conventional MPPT such as hill climbing may show premature convergence, which can significantly reduce the generated power. Metaheuristic optimization algorithms (MOAs) have been used to avoid this problem. The main shortcomings of MOAs are the low convergence speed and the high ripples in the waveforms. Several strategies have been introduced to shorten the convergence time (CT) and improve the accuracy of convergence. The proposed technique sequentially uses a recent optimization algorithm called Mexican Axolotl Optimization (MAO) to capture the vicinity of the global peak of the P–V characteristics and move the control to a fuzzy logic controller (FLC) to accurately track the maximum power point. The proposed strategy extracts both the benefits of the MAO and FLC and avoids their limitations with the use of the high exploration involved in the MOA at the beginning of optimization and uses the fine accuracy of the FLC to fine-track the MPP. The results obtained from the proposed strategy show a substantial reduction in the CT and the highest accuracy of the global peak, which easily proves its superiority compared to other MPPT algorithms.