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In this study, we aimed to compare and contrast the intralimb coordinative patterns of habitual forefoot strikers (FFS) and rearfoot strikers (RFS) during steady‐state running across three different shoe types: minimalist, neutral and cushioned shoes. To describe these coordinative patterns, we implemented the concept of the 'preferred movement path' which represents the movement path that runners naturally select in response to their physical capacity and external environment. We quantified cycle‐to‐cycle consistency (ACC) and within‐trial variance in coordination patterns (SoV) using joint angle data from the ankle and knee for ankle‐knee coupling and from the knee and hip for knee‐hip coupling. Additionally, we calculated the measure of shape difference in joint coupling as the sum of squared distances (SSD) between/within conditions and groups. The percentage of runners who displayed shape differences below certain SSD thresholds was also evaluated. Our findings revealed no significant group or shoe type effect on any of the variability measures (ACC: p = 0.460 for ankle‐knee and p = 0.832 for knee‐hip; SoV: p = 0.345 for ankle‐knee and p = 0.755 for knee‐hip). However, there was a significant (p < 0.001) shape difference observed between the most extreme shoe conditions. Despite this, when runners switched shoes, 70%–90% of them maintained their original coordinative pattern across both joint couplings, indicating a strong adherence to their preferred movement path. This suggests that while shoe type can influence the shape of the coordinative pattern, the inherent movement tendencies of the runners remain largely consistent. Highlights: The study found no differences in the cyclogram variability between habitual foot strike classification groups when wearing different shoes.The largest number of different movement responses was present at the ankle‐knee coupling.A significantly greater proportion of participants changed their ankle‐knee and knee‐hip coordinative patterns between the High versus Low Minimal Index (MI) conditions compared to the other shoe comparisons.No differences were found between the groups in terms of cyclogram variability. [ABSTRACT FROM AUTHOR]

Neuromuscular deficits at the proximal or distal to the knee may contribute to knee valgus and anterior cruciate ligament (ACL) injury. A valgus or abducted position of the knee greater than 12° for females is suggested to be an indicator of the risk of lower extremity injuries. However, there is a lack of examination regarding neuromuscular patterns in both proximal and distal kinetic chains. The purpose of this study was to investigate the effect of 8 weeks of neuromuscular training on knee valgus and co‐activation of the hip and ankle muscles during a countermovement jump in female athletes with a high risk of ACL injury. Twenty‐eight female athletes, with knee valgus greater than 12°, were randomly assigned into two groups: training (n = 14) and control (n = 14). The following measurements were taken before and after the intervention: co‐activation of Gluteus Maximus‐Tensor Fasciae Latae (GMax‐TFL), Gluteus Medius‐Adductor Longus (GMed‐AL), Tibialis Anterior‐Medial Gastrocnemius (TA‐MG), Tibialis Anterior‐Lateral Gastrocnemius (TA‐LG), Medial Gastrocnemius‐Lateral Gastrocnemius (MG‐LG) muscles, and DKV angle during single‐leg countermovement jump task. Following the intervention, the training group demonstrated increased co‐activation of muscles (except TA‐LG) (P < 0.05). The knee valgus angle in the training group decreased by 5.9° (P = 0.001). Our results demonstrated that neuromuscular training alters muscle activity patterns and the neuromuscular group demonstrated a clinically meaningful and statistical reduction in knee valgus. Highlights: Dynamic knee valgus (DKV) is a risk factor for identifying women with a risk of lower extremity injuries.Muscle activity patterns of the hip and ankle, such as DKV, may be modifiable through neuromuscular training.Neuromuscular training with feedback could reduce excessive DKV at a clinically meaningful level. [ABSTRACT FROM AUTHOR]

This paper presents a four-fingered robotic hand, designed to carry out grasping operations along with different object manipulation tasks. The design of this hand resembles a human hand which is the perfect dexterous robotic gripper. In this paper, the forward kinematics of the designed hand is carried out using the Denavit-Hartenberg (D-H) parameters, to calculate the position and orientation of each of the fingertips. Inverse kinematics of the hand is formulated to compute the different joint angles for different fingertip configurations. Kinematic simulations are realised to estimate the workspace of the four finger robotic hand using the MATLAB interface. All possible fingertip trajectories are plotted in joint space to determine the motion constraints of the developed hand model. The results obtained confirm that the hand is suitable for grasping objects of variable geometry and materials within its workspace. The motion of the fingers is flexible enough for different object manipulation. These analysis shows that this hand is capable to perform the desired tasks successfully. [ABSTRACT FROM AUTHOR]

Rock glaciers are typical periglacial landforms with tongue or lobate morphological shapes and characterized by the distinct front, lateral margins, and often by ridge-and-furrow surface topography textures as well as kinematic characteristics, widely distributed in alpine environments. Multitemporal Synthetic aperture radar interferometry (MT-InSAR), is a remote sensing technique with demonstrated effectiveness for detecting landform kinematics. However, its application to rock glaciers is challenged by temporal decorrelation and atmospheric phase noises due to complex topography and snow cover. We designed a quadtree segmentation and parallel computing-based MT-InSAR method to improve the quality and efficiency of deformation measurement of rock glaciers. We applied the method to a rock glacier inventory of the Nyainqêntanglha Range, China, derived from high-resolution Gaofen-2 images, to quantify the activity rate of each rock glacier. Results showed that 32.1% (6,389) of the identified rock glaciers exhibited slope-parallel deformation rates exceeding 100 mm/y. The activities of the rock glaciers exhibited strong correlations with their distance to glaciers, precipitation, freeze–thaw magnitude, and permafrost occurrence probability. The results demonstrate the effectiveness of the developed segmentation-parallel MT-InSAR method for monitoring rock glacier deformation over a large region. [ABSTRACT FROM AUTHOR]

A new geological-structural map of the southern Serre Massif (SM), in the south-central part of the Calabrian-Peloritani-Orogen (CPO), is provided. CPO is a ribbon-like microplates puzzle, originally belonging to the southern European Variscan Belt and, later involved into the Alpine geodynamics of the central Mediterranean Area. The SM represents one of the key European Variscan basement relicts, because of its exhumation mechanisms as well as for the absence of any Alpine metamorphic overprint. This map has the aim to better delineate the sequence of the Variscan blasto-deformational relationships consisting in a prograde multistage history, followed by an extensional/transpressional multistage retrograde evolution, which triggered the intrusion of the former plutonic products. The mylonitic fabric resulted finally replaced by the effects of the late- to post-kinematic plutonic intrusions coeval with a former late-Variscan exhumation stage, followed, during Mesozoic, by carbonate platform sedimentation, before to be completed exhumed during the Oligocene-Miocene Alpine stages. [ABSTRACT FROM AUTHOR]

This research presents the mathematical modelling of kinematic and complete dynamic analysis of a novel over-constrained parallel mechanism, which consists of two universal-prismatic-revolute joint limbs and one revolute-revolute-universal joint limb. The kinematic model is constructed based on the closed-loop vector method and the velocity Jacobian matrix is deduced, velocity-mapping relationships between all moving components and moving platform are also performed. Afterwards, inertia and applied forces are analysed, the complete dynamic equations with the classical Stribeck friction model of the proposed structure is established based on the principle of virtual work. A theoretical numerical example is given to solve kinematics and dynamics solutions, and theoretical forces from developed dynamic formulation are verified by the physic model simulation in Simscape and the rigid-flexible coupling model simulation in Adams. A good agreement between the theoretical results and multi-body software simulation is found. [ABSTRACT FROM AUTHOR]

Due to limited weight and stiffness, large-scale robots are susceptible to structural oscillations during operation. In this publication, a model for the vertical dynamics of an aerial rescue ladder as an application example for large scale flexible robots is derived based on the Lagrange formalism. The model consists of five flexible segments, each using an arbitrary number of flexible modes. Kinematic loops occurring due to the type of interconnection between the telescopic elements are implicitly solved by the chosen assumed modes. Linearized system matrices are extracted from the model directly and very efficiently. In the resulting modelling process, the manipulator is solely described by its position and orientation kinematics and thus an adaption to different kinds of manipulators is straightforward. A validation against real world measurement data confirms the high accuracy of the derived model. [ABSTRACT FROM AUTHOR]

With the development of science and technology, robots have become an integral part of human life. To ease human efforts in tedious and repetitive tasks, robots are used in human platforms. The current analysis is focused on the design and development of a robotic manipulator to perform pick and place like operations. First, the kinematic analysis is performed on different links of the designed manipulator to know its workspace and singularity. Each link of the manipulator is modelled in SOLIDWORKS software and simultaneously imported to V-REP software. In the V-REP software, links are grouped to form the manipulator arm. Each link is attached to a joint. After formation of the manipulator arm, simulations for different physical operations are performed. While performing different physical operations with the manipulator arm, graphical analysis is performed for position, velocity and acceleration of revolute joints. The force required for the prismatic joint to hold the object is also calculated. The results obtained from the simulation analysis reveal that the manipulator can work satisfactorily in the practical environment. Finally, the results are compared for manipulators of different degrees of freedom to obtain the workspace required for a smooth operation. The current study holds a large importance in robotics field as mobile manipulators are extensively used in different industries and the same analysis can also be extended towards other forms robots. Abbreviation: DLS: Damped Least Square DH: Denavit-Hartenberg V-REP: Virtual Robot Experimentation Platform IK: Inverse Kinematics [ABSTRACT FROM AUTHOR]

Tensegrity mechanisms are lighter weight, lower inertial force and higher strength to weight ratio compared with conventional ones. This paper proposes a four-DOF automatic device for polishing the surface of a workspiece, in which a passive tensegrity-based parallel mechanism is connected to an industrial robot arm through an adjustable spring-loaded prismatic joint. The device consists of moving and base platforms that are connected by three compliant spring legs and one rigid central leg. A major advantage of this device is that attitude of polishing tool mounted on the moving platform can be changed automatically to fit the polished workspiece surface without any sensors, due to the three compliant spring legs. The kinematics, statics and stiffness problems of the mechanism are considered and solved. Finally, an experiment is executed on the surface of a discarded car shell, to verify the reliability of the polishing device within ranges of some parameters. [ABSTRACT FROM AUTHOR]

In the present study, an innovative concept of axial flapping wing model is analysed to study and improve the aerodynamic efficiency for vertical takeoff microaerial vehicle. The flapping kinematics are inspired by merging aquatic jellyfish locomotion, and umbrella's in and out mechanisms with the flappers hinged around a central hub. Also, additional flappers are placed beneath the primary flappers at varied distances. The analysis is performed using FLUENT to study the effect of placing axial flappers that maximize the lift/drag ratio. The chord length of the primary flappers is fixed at 10 cm, and axial flappers at 5 cm as the model needs to be constrained according to DARPA regulations of 15cm. The flapping kinematics are chosen as inward, outward, and symmetrical based on the feasibility of flapping in the axial direction to produce the airflow for generating lift in the vertical direction. The amplitude of the flappers is set at 30° to have a comparative study of other kinematics. The flow structures developed by the interactions of vortices of flapping wings influence the aerodynamic characteristics of the model. The velocity and vorticity magnitude of the flappers are studied and analysed in detail to understand the mechanism of axial flappers in providing better lift/drag ratio. The effect of adding additional flappers underneath the primary flapper model under inwards kinematics was better than primary flapper (Model 0) which significantly increased the aerodynamic performance of axial flapper's inter-distance variations at 5 cm by 18.3% (Model 1), at 10 cm by 15.2% (Model 2) and at 15 cm by 10.5% (Model 3). The outward and symmetric kinematics models exhibit a decrease in aerodynamic efficiency compared to inward kinematic models. [ABSTRACT FROM AUTHOR]

Background: In infants with indications of upper cervical dysfunction, the Flexion-Rotation-Test and Lateral-Flexion-Test are used to indicate reduced upper cervical range-of-motion (ROM). In infants, the inter-rater reliability of these tests is unknown. Objective: To assess the inter-rater reliability of subjectively and objectively measured ROM by using the Flexion-Rotation-Test and Lateral-Flexion-Test. Methods: 36 infants (<6 months) and three manual therapists participated in this cross-sectional observational study. Pairs of two manual therapists independently assessed infants' upper cervical ROM using the Flexion-Rotation-Test and Lateral-Flexion-Test, blinded for each other's outcomes. Two inertial motion sensors objectively measured cervical ROM. Inter-rater reliability was determined between each pair of manual therapists. For subjective outcomes, Cohen's kappa (ĸ) and the proportion of agreement (Pra) were calculated. For objectively measured ROM, Bland Altman plots were conducted and Limits of Agreement and Intraclass Correlation Coefficients (ICC) were calculated. Results: The inter-rater reliability of the Flexion-Rotation-Test and Lateral-Flexion-Test for subjective (ĸ: 0.077–0.727; Pra: 0.46–0.86) and objective outcomes (ICC: 0.019–0.496) varied between pairs of manual therapists. Conclusion: Assessed ROM largely depends on the performance of the assessment and its interpretation by manual therapists, leading to high variation in outcomes. Therefore, the Flexion-Rotation-Test and Lateral-Flexion-Test cannot be used solely as a reliable outcome measure in clinical practice and research context. [ABSTRACT FROM AUTHOR]

Objectives: This study compares people with recurrent low back pain (rLBP) and people with pre-clinical low back pain (standing-induced low back pain developers; PDs) to each other and back-healthy controls (non-pain developers; NPDs). Movement variability and muscular co-activity related to coordination are important for both rLBP and PDs, and these two groups also have altered static spine extension. Methods: Eleven participants with recurrent low back pain, and twenty-one asymptomatic participants, categorized as PDs (11) and NPDs (10) through an established standing protocol, volunteered for this study. Three phases of standing extension motion (lean, hold, and return to neutral) were analyzed. Root mean square angular jerk was calculated from trunk and pelvis kinematics, co-activation of the trunk and hip musculature were assessed in four-muscle sets. Results: Root-mean-square jerk was greater when returning to neutral than when leaning back during standing extension in all three groups. People with rLBP had reduced co-activity in their trunk extensors, people classified as PD had more co-activity in their hip extensors compared with the other groups, and anterior trunk co-activity was phase-dependent, and similar between groups. Discussion: Movement control alterations with low back pain may start as an over-protective co-activation strategy in those with standing-induced LBP and progress to an under-protective strategy in those with recurrent low back pain. Level of Evidence: 3. [ABSTRACT FROM AUTHOR]

In this work, Multi Temporal Interferometry techniques (MTI) based on advanced synthetic aperture radar differential interferometry (A-DInSAR) have been investigated for the monitoring of deformation phenomena in slow kinematics. A-DInSAR methodologies include both Coherence-based type, as well as Small Baseline Subset (SBAS) that Permanent Scatterers (PS). These techniques are capable to provide wide-area coverage and precise, spatially dense information on ground surface deformations. MTI techniques have been applied to the town of Stigliano (MT) in Basilicata Region (Southern Italy), where the social center building has been destroyed after the reactivation of a known landslide. A direct comparison of the results has been shown that PS and SBAS techniques are comparable in terms of obtained coherent areas and displacement patterns, with slightly different velocity values for individual points. In particular, PS furnished a range of velocity between −5/−25 mm/year, while for SBAS we found values around −5/−15 mm/year. Furthermore, on the crown of the landslide body, a Robotics Total Station measuring distance values on 24 points has been installed. The displacement values obtained are in agreement with the results of the MTI analysis, showing as these techniques could be a useful in the case of early-warning situations. [ABSTRACT FROM AUTHOR]

Research being done on a stable platform is to isolate moving carrier's motion, which can keep attached equipment stable and reduce the influence of the moving carrier. Motion compensation is analysed for a horizontal stable platform by means of coordination transformation and the parallel mechanism's direct and inverse kinematics solution. The platform has only three rotational degrees of freedom (DOFs) in three directions, which is composed of a 2-DOF spherical mechanism and a motor on it in series. When the carrier's orientation has changed, the 2-DOF spherical parallel mechanism can keep the platform horizontal by utilising the motors' drive. Firstly, the platform's kinematics are analysed and the transformation matrix of the 2-DOF parallel platform, independent of motion carrier is derived. Then by the method of coordination transformation the analytical resolution of motors' compensation is obtained, which is for keeping the parallel platform horizontal when the motion carrier's orientation changed, the result is verified by the numerical method and experimental process. Because of the influence of objective factors, the experimental results are approximately in agreement with the theoretical results, but there are numerical deviation and time lags. Finally, when the parallel mechanism is used for stable platform, some of the research work that should be solved is discussed. The research of this paper provides a theoretical basis for the application of a stable platform, and lays the foundation of the experiment. [ABSTRACT FROM AUTHOR]

Cenozoic convergence, collision and subsequent subduction between African and Eurasian plates are accommodating in overriding Eurasian plate both forming the Aegean extension and the North & East Anatolian fault zones. To understand the kinematic evolution of upper crust, here we provide new paleostress data from the Havran-Balıkesir Fault Zone located at the interaction area between the North Anatolian Fault Zone (NAFZ) and west Anatolian extensional structures. Paleostress reconstructions of fault-slip data reveal that three distinct deformation phases have been experienced in the region. Phase 1 is represented by left-lateral strike-slip faulting with reverse component in the pre-Pliocene period. The Phase 2 is characterized by approximately N-S trending contraction and associated E-W trending extension in Plio-Quaternary, which is spatiotemporally linked to the initiation of NAFZ through the area. The youngest deformation, Phase 3 is attributed to NE-SW trending extension and NW-SE-trending contraction commenced by the Quaternary transpressional tectonics in Southern Marmara Region. These results show that the main contraction axes have been experienced a spectacular anticlockwise rotation (from NW-SE to E-W), which is associated with; (i)the propagation geometry of the NAFZ into the region (ii)slab roll-back and retreat and tearing process on the Aegean subduction system, and (iii)the existence of inherited structures of the İzmir-Balıkesir Transfer Zone. [ABSTRACT FROM AUTHOR]

In the present work, a new class of finite elements (FEs) for the analysis of composite and sandwich plates embedding piezoelectric skins and patches is proposed. By making use of node-by-node variable plate theory assumptions, the new finite element allows for the simultaneous analysis of different subregions of the problem domain with different kinematics and accuracy, in a global/local sense. As a consequence, the computational costs can be reduced drastically by assuming refined theories only in those zones/nodes of the structural domain where the resulting strain and stress states, and their electro-mechanical coupling present a complex distribution. The primary advantage is that no ad-hoc techniques and mathematical artifices are required to mix the fields coming from two different and kinematically incompatible adjacent elements, because the plate structural theory varies within the finite element itself. In other words, the structural theory of the plate element is a property of the FE node in this present approach, and the continuity between two adjacent elements is ensured by adopting the same kinematics at the interface nodes. The finite element arrays of the generic plate element are formulated in terms of fundamental nuclei, which are invariants of the theory approximation order and the modeling technique (Equivalent-Single-Layer, Layer-Wise). In this work, the attention is focused on the use of Legendre polynomial expansions to describe the through-the-thickness unknowns to develop advanced plate theories. Several numerical investigations, such as composite and sandwich multilayered plates embedding piezoelectric skins and patches with various load, boundary conditions, and piezoelectric material polarizations, are carried out to validate and demonstrate the accuracy and efficiency of the present plate element, including comparison with various closed-form and FE solutions from the literature. [ABSTRACT FROM AUTHOR]

We propose a novel method for estimating population-level and subject-specific effects of covariates on the variability of functional data. We extend the functional principal components analysis framework by modeling the variance of principal component scores as a function of covariates and subject-specific random effects. In a setting where principal components are largely invariant across subjects and covariate values, modeling the variance of these scores provides a flexible and interpretable way to explore factors that affect the variability of functional data. Our work is motivated by a novel dataset from an experiment assessing upper extremity motor control, and quantifies the reduction in movement variability associated with skill learning. The proposed methods can be applied broadly to understand movement variability, in settings that include motor learning, impairment due to injury or disease, and recovery. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

In this work, a new class of finite elements for the analysis of composite and sandwich shells embedding piezoelectric skins and patches is proposed. The main idea of models coupling is developed by presenting the concept of nodal dependent kinematics where the same finite element can present at each node a different approximation of the main unknowns by setting a node-wise through-the-thickness approximation base. In a global/local approach scenario, the computational costs can be reduced drastically by assuming refined theories only in those zones/nodes of the structural domain where the resulting strain and stress states, and their electro-mechanical coupling present a complex distribution. Several numerical investigations are carried out to validate the accuracy and efficiency of the present shell element. An accurate representation of mechanical stresses and electric displacements in localized zones is possible with reduction of the computational costs if an accurate distribution of the higher-order kinematic capabilities is performed. On the contrary, the accuracy of the solution in terms of mechanical displacements and electric potential values depends on the global approximation over the whole structure. The efficacy of the present node-dependent variable kinematic models, thus, depends on the characteristics of the problem under consideration as well as on the required analysis type. [ABSTRACT FROM AUTHOR]

This paper suggests the dimensional synthesis of a planar five-bar mechanism of variable topology using dyadic and triadic techniques. The mechanism consists of two binary links with two offset tracing points and transmits motion between two extreme positions. Synthesis of mechanism for standard kinematic task is considered. The analytical displacement equations have been written using complex numbers. The effectiveness of mechanism synthesis has been demonstrated on a numerical example. The equations are solved and verified using MATLAB. The main attractions of method are simplicity, reduced solution space, non-iterative results and better accuracy due to non-dependence on graphical techniques. [ABSTRACT FROM AUTHOR]

The Mount Pizzuto earth flow has been periodically active in recent decades. Early in 2006, it surged and created a dam across the Ginestra torrent. Episodic floods induced by the earth-flow dam periodically damaged a section of a local road and power and telephone service lines. This paper presents a map showing deformational structures along the flow and a geometric reconstruction of thrust faults at the earth-flow toe from 2006 to 2014. The map, produced on the basis of field observations, shows the spatial distribution of back-tilted surfaces, flank ridges and normal, thrust, and strike-slip faults. Springs, creeks, and ponds are also shown on the map. The map indicates that the earth flow is composed of five kinematic zones. Cartographic data and the spatial–temporal reconstruction of the thrusting evolution offer the basis for interpreting the (mid-term) kinematics of the flow and its controlling factors, and for assessing the influence of earth-flow movement on torrent channel capacity. [ABSTRACT FROM AUTHOR]

This paper proposes a novel full kinematic incremental forming process, called three opposite point incremental forming (TOPIF), in which one pair of main opposite forming tools and two pairs of auxiliary opposite tools as the supporting dynamic die are utilized to perform the components along a predefined path. Compared to the conventional kinematic incremental sheet forming (KISF) and SPIF, the process can effectively control the local deformation, improve geometric accuracy and increase the ability to form complex curved surface. The deformation analysis on TOPIF is the key to control the local deformation. A deformation analysis and the strain distributions are proposed based on a plane strain deformation mode. The results by the deformation analysis of a truncated conical shape are in accord with experimental values for 1 mm Al5052. [ABSTRACT FROM AUTHOR]

Monitoring the response of engineering structures, such as tall buildings, tower and large-scale bridges, under severe loading conditions, such as strong earthquake or wind storm, is an important requirement to verify their design and construction and to evaluate structural condition and reliability. In the last two decades, high-rate real-time or post-processed kinematic differential Global Positioning System (DGPS) has been widely used in dynamic displacement measurements of civil engineering structures. In recent years, interest has increased for Precise Point Positioning (PPP) due to its capability to generate positioning solutions as accurate as DGPS. In this study, the potential of post-processed kinematic PPP in terms of monitoring dynamic displacement response of a structure has been explored based on free damped oscillation events obtained from a model structure, which is able to vibrate in the fundamental and higher modes of vibration. A number of experiments have been carried out and five events, each of which is different character, have been selected to compare PPP results with DPGS results in the time and frequency domain. The results clearly demonstrate that the PPP method, like the DGPS method, offers great potential for the measurement of horizontal and vertical dynamic movement of structures. The impact of a short period (one minute) of observation length on the result of the kinematic PPP method was also investigated in terms of sensing the dynamic movement of a structure. Twenty selected one-minute data-sets extracted from a one-hour original data-set were processed by Canadian spatial reference system PPP and each one-minute PPP solution was compared with the corresponding segment obtained from the one-hour PPP solution. The results show that the one-minute PPP solution is able to extract the fundamental natural frequency of the oscillation in the horizontal and vertical component just like the one-hour PPP solution after the offset is removed and the lower frequency trend component is filtered out. [ABSTRACT FROM PUBLISHER]

Steep mountainous areas account for 70% of all river catchments in Japan. To predict river discharge for the mountainous catchments, many studies have applied distributed hydrological models based on a kinematic wave approximation with surface and subsurface flow components (DHM-KWSS). These models reproduce observed river discharge of catchments in Japan well; however, the applicability of a DHM-KWSS to catchments with different geographical and climatic conditions has not been sufficiently examined. This research applied a DHM-KWSS to two river basins that have different climatic conditions from basins in Japan to examine the transferability of the DHM-KWSS model structure. Our results show that the DHM-KWSS model structure explained flow regimes for a wet river basin as well as a large flood event in an arid basin; however, it was unable to explain long-term flow regimes for the arid basin case study. [ABSTRACT FROM AUTHOR]

In this work, a novel planar compliant tensegrity-like parallel mechanism composed of a set of rods and strings is introduced. The mechanism has low mass and high strength to weight ratio compared with conventional parallel mechanisms. An energy based method is employed to find the analytical solutions to the forward and inverse position analysis. Afterwards, the singular configurations are detailed. The actuator and output workspaces are then mapped. Moreover, an analytical approach based on an energy formulation is used to evaluate the stiffness of the mechanism. Finally the characteristics of the mechanism are reported. [ABSTRACT FROM AUTHOR]

Titanium oxide is as ancient in age as our planet but its use for photoanode is more recent. It exists naturally as rutile (the second most abundant), anatase and brookite ores. The anatase several metastable states trigger diverse spectral responses with Magnifera Indica Linn. (M.indica L) dye as it is synthesized with an N719 dye grown on its matrix. Facile doctor blade method and high temperature sintering at 723 K were used in fabrication. Doping of titanium oxide in effect lowers the band gap of TiO2 for photo-excitation caused by a bathochromic shift and simultaneously decreases the rate of recombination in photogenerated electron-hole pairs. This study explored the visible light induced photocatalytic action of doped M.indica L DSSC towards reduction of titanium oxide bandgap. The SEM micrographs reveal the molecular interactions and the interplay as electrolytes percolate the intricate N719 dye/Titania framework. Detailed analysis stem from comparison of M.indica L crude faction and the batch separated faction using FTIR spectroscopy. The absorbance peak, rates of reaction and % transmittance identify the particular chromophores responsible for the reaction. Result shows the batch-separated hexane faction approximately 1000 times more efficient than its crude faction although the ff of the crude was only about twice that of the hexane faction. The optical study showed that doping ions lead to an increase in the absorption edge wavelength, and a decrease in the band gap energy of TiO2 nanoparticles. The doped TiO2 nanoparticles in general showed higher photocatalytic activities than the pure ones. [ABSTRACT FROM AUTHOR]

Measuring cervical spine kinematics in rugby scrummaging is important from an injury prevention perspective. However, choosing an appropriate measurement system is challenging. Since reliability of a measurement system is critical for meaningful interpretation of results, this study evaluated test-retest reliability of an electromagnetic tracking and optoelectronic motion capture system for measurement of cervical spine kinematics during scrummaging. Reliability of joint kinematics at discrete time points was evaluated using intraclass correlation coefficients (ICC), standard error of measurement (SEM), and minimal detectable change (MDC). Reliability of kinematic curves was assessed using coefficient of multiple correlations (CMC) and standard deviations (curve SD). In both systems, seven ICC values were considered to be excellent (>0.75), while two were fair to good (0.44-0.66). Minimal detectable change values for flexion/extension were found to be higher than for other movement directions, and CMC values were only moderate. Overall, reliability was comparable in both systems. [ABSTRACT FROM AUTHOR]

With ergometers being frequently used in training programmes of rowers, consensus is needed to identify which design most closely reproduces the biomechanics of on-water rowing. Discussion exists about the movement allowed to the stretcher, with static designs fixating it, while dynamic models allowing displacement. To investigate how this affects muscular and kinematic coordination patterns, a group of nine male rowers were analysed whilst exercising on three ergometer designs, a static ergometer and two dynamic versions. 3D motion analysis was applied to measure displacement of body segments, joint angles and angular velocities. Electromyography was used to record activation patterns of major muscles. All participants were measured on all three ergometer designs; data were analysed using repeated measures ANOVA. Duration of the stroke phase turned out to be longer on the static ergometer and tibialis anterior and biceps femoris coordination patterns differed between static and dynamic ergometers. Kinematic data showed a more squatted posture at the end of recovery on the static ergometer. These differences were interpreted as distorted movement coordination resulting from the more inert moving mass on the static ergometer. [ABSTRACT FROM AUTHOR]

Background: Missing active ankle control limits prosthetic walkers in their ability to control mediolateral balance. Mediolateral balance control may be improved by increasing hip strategy effectiveness. To this purpose, a new, patented prosthetic device has been developed. This paper presents the design of a study focused on validating the prototype on improvements of mediolateral balance control by comparing it to a classic prosthetic set-up. Methods: Ten adult unilateral transfemoral amputees and ten age- and weight-matched (± 10%) able-bodied individuals will walk on the Gait Real-time Analysis Interactive Lab. Subjects will perform three walking tasks: (1) Unperturbed walking at 80%, 100%, and 120% of comfortable velocity, (2) walking while being mediolaterally perturbed, and (3) walking while stepping on projected light beams. Full-body kinematic and kinetic data will be recorded. Various walking and balance parameters will be analysed. Discussion: It is expected that by increasing hip ab-/adduction effectiveness, the prototype will improve mediolateral balance control in prosthetic walking. Also, it is expected that the prototype will reduce asymmetric lateral trunk bending. Finally, this study will provide valuable new insights into mediolateral balance control during prosthetic walking. [ABSTRACT FROM AUTHOR]

Gear-shifting mechanism has a key role in transmission system of a vehicle. During gear shifting, there is a risk of losing the engine optimal speed that will ultimately lead to more emission from the vehicle. It is demanded for optimal performance of transmission systems to increase quality of synchronizer used for gear shifting. Especially in the case of heavy vehicles, the synchronizer performance needs to be robust more even during different operating scenarios. Synchronization process varies by changing its parameters values. So one of the ways to improve performance of the synchronizer is to optimizing its parameters. In the paper, a generic synchronizer mechanism (GSM) is considered. Mathematical model of GSM is presented based on constrained Lagrangian formalism (CLF) and detailed kinematics of synchronization process in transmission system. Speed difference at the end of the main synchronization phase and synchronization time are chosen as two objectives. The following eight parameters of the synchronizer have taken as input parameters: cone angle, cone coefficient of friction, cone radius, rate of shift force, blocker angle, blocker coefficient of friction, gear moment of inertia, and ring moment of inertia. Influence of the parameters on objectives is studied. The values of the objective functions decrease with increasing some of the parameters and increase with increasing others. Not only the objective functions have opposite behavior between the parameters but also have opposite behavior with variation of the same parameters. For example, the synchronization time decreases but the speed difference increases with increasing cone coefficient of friction. The Matlab routine of multi-objective optimization is applied to obtain the optimized parameter values of the generic synchronizer at different operating conditions. In the first case, the sleeve is considered as a master, in the second case the gear is considered as master, and in the third case both sleeve and gear are considered as slaves. In each case, three different operating conditions are studied which are nominal, transmission vibrations, and road grade. The obtained results of biobjective optimization (Pareto fronts, Pareto sets, and corresponding performance diagrams) are analyzed and the most influencing synchronizer parameters have been identified. [ABSTRACT FROM AUTHOR]

A railway derailment is usually an unpredictable event where the damage could range from a simple train delay to a big loss of goods, assets (rolling stock and permanent way) and, in extreme cases, even human lives. Therefore, Brazil’s railways are always implementing actions that minimize the risk of a derailment. One of the main actions is to establish tight maintenance criteria for rolling stock and for track geometry. However, these criteria usually do not consider the vehicle dynamics and the geometry of the permanent way together. Thus, this paper develops a mathematical model of a high capacity railcar together with the flexible support of the track to determine a method of assessing bounce, roll and pitch motions from instrumented wagons, so this method can be used in routine inspections. The mathematical model was satisfactorily validated by comparing the natural frequencies obtained from the model and from a real vehicle tested in the field. In addition, the model results were compared against field measurements from an instrumented wagon and a track geometric vehicle. A strategic method for operational safety analysis was suggested and used, which was able to determine the wavelength of permanent way anomalies that should be given priority for maintenance actions as well as considered when adopting speed restrictions. [ABSTRACT FROM PUBLISHER]

The ability of animals to propel themselves efficiently through a fluid medium is ecologically advantageous. Flexible components that influence vortex interactions are widespread among animal propulsors. However the mechanisms by which vortices are enhanced and appropriately positioned for thrust generation are still poorly understood. Here, we describe how kinematic propulsor movements of a jellyfish can enhance and reposition a vortex ring that allows the recapture of wake energy for secondary thrust generation and efficient locomotion. We use high-speed video and digital particle image velocimetry (DPIV) to resolve kinematics simultaneously with fluid structures. These results provide new insight into how animals can manipulate fluid structures to reduce metabolic energy demands of swimming muscles and may have implications in bio-inspired design. [ABSTRACT FROM PUBLISHER]