Forward Inclination Research Articles

Experimental study on the dam-break-induced surge impact on an inclined wall

The front faces of coastal structures are not always perpendicular to its foundation. To investigate the surge impact characteristics on an inclined wall, laboratory experiments about the dam-break-induced surge impact were conducted on downstream walls with four different inclination angles, i.e., −30°, −10°, 0°, and 10° (positive for forward inclination). Before the water tongue forms, surge water in front of the wall can be classified into the bottom solid water and the upper aerated water. Although the measured maximum water level is the largest in front of the vertical wall, it contains a large proportion of aerated water. In contrast, the −30° wall exhibits the largest proportion of solid water, which is associated with the force exerted on the wall. As the wall inclines forward, the impact pressure experiences an increase in its peak value and spatial extent, while a decrease in its duration. The maximum impact pressure and the maximum horizontal force induced by the initial impact increase from the backward to forward inclination, while the maximum horizontal force in the transition or quasi-static phase increases as the wall inclines. In addition, it is found that the calculation method for designing breaking wave loads on nonvertical walls underestimates the surge-induced maximum horizontal force. Regarding the potential sliding/overturning failure, the 10°/−30° wall presents the highest risk among the considered cases under the same incoming hydrodynamic conditions. These findings extend our understandings on the surge–structure interactions, being helpful for the safe design of relevant coastal structures.

Postoperative Changes of Spinopelvic Sagittal Parameters After Cervical Laminoplasty for Cervical Spondylotic Myelopathy.

A retrospective analysis of prospectively collected data. To investigate postoperative changes of spinopelvic sagittal parameters after laminoplasty for cervical spondylotic myelopathy (CSM) accompanying postoperative cervical kyphotic deformity or cervical regional sagittal imbalance. To the best of our knowledge, no study has been reported concerning postoperative changes of spinopelvic sagittal parameters accompanying postoperative deterioration of cervical sagittal alignment or balance after cervical laminoplasty. Forty-five CSM patients without preoperative cervical kyphosis who underwent laminoplasty were included. None of the 45 patients had a medical history of previous spine surgery, hip joint surgery, or knee joint surgery. The patients were divided into 2 groups (kyphosis and lordosis groups) according to postoperative C2-7 angle, and they were also divided into 2 other groups (imbalance and balance groups) according to postoperative C1-7 sagittal vertical axis. Postoperative changes (Δ) of T1 slope (T1S), thoracic kyphosis, thoracolumbar kyphosis (TLK), lumbar lordosis (LL), Pelvic tilt, and C7 sagittal vertical axis were measured comparing lateral radiographs of the whole spine in the standing position taken at 1 year postoperatively with those before surgery. Both T1S and TLK significantly decreased after cervical laminoplasty in the kyphosis group compared with the lordosis group. On the other hand, both T1S and TLK increased significantly, and LL significantly decreased after surgery in the imbalance group compared with the balance group. At 1 year after laminoplasty for CSM, both T1S and TLK significantly decreased accompanying postoperative cervical kyphotic deformity as a compensatory action for postoperative cervical kyphosis to maintain the global sagittal balance of the spine, whereas both T1S and TLK increased significantly, and LL significantly decreased accompanying postoperative cervical reginal sagittal imbalance which resulted in postoperative forward inclination of the whole spine.

Inclined battery cells for mitigating damage in undercarriage collision

Undercarriage collision is dangerous for electric vehicle as battery pack is usually integrated into the vehicle floor. If battery pack is ploughed by obstacle on road, battery cells could be damaged, increasing risk of occurrence of internal short circuit and thermal runaway. To tackle the problem, we came up with inclined layout of battery cells for reducing damage in undercarriage collision. Using numerical simulations, we show why inclined battery cells can alleviate damage in undercarriage collisions. The load cases include vehicle’s initial speeds from 20 to 100 km/h and battery pack clearance overlapped with obstacle from 10 to 30 mm. Aligned with the new cell-to-pack packaging trend, the battery pack model used in this study only includes large size battery cells and has no module-level assemblies. A homogenised model of deformable battery cell was adopted for assessing damage. The results have shown that forward inclination of battery cells can reduce scraping resistance to battery pack, and thus lower the impact energy transferred to battery cells and jellyrolls. The 20° forward inclination was found to deliver better safety performance than the other layouts. Optimal inclination angle depends on structural design of battery pack and battery cells. In general, the safety enhancement is more prominent in severer undercarriage collisions.

Design and Experiment of Row Cleaner with Staggered Disc Teeth for No-Till Planter

In view of the large amount of wheat straw coverage and the difficulty with the high-speed working process used in traditional rotary tillage row cleaner. A row cleaner with staggered disc teeth for no-till planting was designed. It was determined that installation with a forward inclination α, horizontal declination β, and forward speed v0 of the machine were the main factors affecting the straw cleaning rate Y1 and working resistance Y2, and the range of values for structural parameters and motion parameters of the row cleaner were determined. Taking α, β, and v0 as the factors and Y1 and Y2 as the response indexes, using EDEM 2018 software to simulate the straw cleaning process under different parameters and determine the influence of each parameter on the straw cleaning performance. After performing a soil bin test, the results showed that there was no straw entanglement and blockage, and the passability was better than that of the traditional flat disc separated row cleaner. When α was 70°, β was 30°, v0 was 8 km/h, and the embedded depth h of the soil (straw) was 55 mm, the average straw cleaning rate was the highest, which was 90.59%. This study provides a new idea for the design of high-speed corn no-till planters in the Huang-Huai-Hai area of China.

A comprehensive study of the aerodynamic characteristics of an aspect ratio of 6.25:1 inclined square prism

Inclined prismatic structures have grown in popularity in civil engineering due to increased architectural and aesthetic demands, leading to a surging need to study their aerodynamic properties. In this study, an inclined square prism was examined using wind tunnel tests and numerical simulations with an aspect ratio of 6.25:1. The Synchronous Multi-Pressure Sensing System (SMPSS) wind tunnel technique was used to evaluate the aerodynamic characteristics of the structure, including surface pressure distribution, local force spectra, force coefficient, coherence, and the Strouhal number. Moreover, the numerical Large-eddies simulation (LES) were also deployed to investigate the flow field morphology around the structure. Results show that the orientation, direction, and angle of inclination direction significantly affect the prism’s aerodynamic characteristics. Several flow field phenomena were also revealed. Forward inclination enhances the downwash flow, whereas the backward counterpart enhances the upwash flow, and transverse inclination produces a noticeable modification in the vortex morphology near the prism base. These findings can inform structural design and contaminant dispersion efforts.

Characteristics of Pressure on the Apophysis in the Course of Paediatric Heel Pain—Preliminary Report

Increased pressure on the heel apophysis is often implicated as a cause of paediatric heel pain. However, there are few reports on the causes of the increased pressure and its origin. Therefore, the aim of this study was to analyse the distribution of pressure on the feet in children with heel pain. The study included 33 paediatric patients with non-traumatic heel pain, i.e., 24 boys (73%) and 9 girls (27%), aged on average 11.2 years (±3 years). Pedobarographic diagnostics proved a decrease in the pressure on the heels in relation to the ground and the transfer of the projection of the centre of gravity to the forefoot. While standing, the average contribution of the pressure on the heel was 0.52, SD = 0.14 in children with normal and reduced weight. In overweight children, the average pressure on the heel was higher (0.60, SD = 0.08), but the small number of children with this characteristic (n = 4) did not allow conclusions to be drawn in this area. Heel underload was also demonstrated during gait. However, the assessment of this aspect requires additional observational analyses in the field of propulsion and gait phases. The reduced pressure on the heel promotes apophysis traction, causing intracanal compression. Studies have shown that the causes of apophysis traction may be postural defects (in particular, forward inclination of body posture) and overpronation of the foot, or defects in the metatarsal area.

Parameter Optimization and Experiment of a Seed Furrow Cleaning Device for No-Till Maize Seeding

To avoid the issues of seeds lying atop straw, where the seeds cannot germinate, during no-till maize seeding, a seed furrow cleaning device is proposed. The device uses rotating spring teeth and a curved sliding shovel to clear the straw from the seed furrow to the outside. The critical components of the side throwing mechanism, rotary disc and spring teeth design are analyzed, and the value range of the installation inclination angle, rotating speed and bending angle of spring teeth are determined. The force on the straw at the moment of starting to touch and throw it is analyzed theoretically in the three installation directions of forward inclination, radial and backward inclination on the rotary disc, and the backward inclination of the spring teeth is determined. A simulation model of the seed furrow cleaning device is established by using the discrete element method simulation software; the forwarding speed, rotating speed, installation inclination angle, and bending angle of spring teeth are used as influencing factors to carry out single-factor experiments. The influence characteristics of different parameters on seed ditch cleaning effect are analyzed from the aspects of straw cleaning quantity and soil disturbance. A field validation experiment is carried out, and the results show that when rotating speed is 180 r/min, installation inclination angle of spring teeth is 40°, and bending angle is 30°, the straw cleaning rate is 82.26%. The research could provide references to develop the no-till seeder for maize seeding.

Effects of a postural cueing for head and neck posture on lumbar lordosis angles in healthy young and older adults: a preliminary study

BackgroundPostural rehabilitation plays an important role in the treatment of non-specific low back pain. Although pelvic inclination has been widely used to improve lumbar lordosis, the effect of cervical anterior inclination on lumbar lordosis in young and older adults in sitting and standing posture is still unclear. This preliminary study was designed to examine the influence of changing the cervical anterior angle on the lumbar lordosis angle, through alterations of the head position under the natural sitting and standing conditions, aiming to provide a basis for establishing a new postural rehabilitation strategy.MethodsThirty-six young (24.0 ± 2.2 years, 14 females and 22 males) and 38 older (68.4 ± 5.9 years, 36 females and 2 males) healthy adults participated in this study. The four spinal regional angles—cervical anterior angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic forward inclination angle, were measured in standing and relaxed sitting postures to determine the effects of a postural cueing for the head and neck posture, “inclining head backward and performing chin tuck,” on lumbar lordosis angle.ResultsIn the standing posture, the pelvic forward inclination angle in the older adult group was significantly smaller (P < 0.001, by ANOVA) than that in the young adult group and increased significantly (P < 0.001) in response to the postural cueing. In addition, the thoracic kyphosis angle in the standing (P = 0.001) and sitting (P = 0.003) positions was significantly reduced in response to the postural cueing. However, the lumbar lordosis angle in response to the postural cueing increased significantly in both the standing position (P < 0.001) and sitting position (P < 0.001).ConclusionThe results suggest that increasing the cervical anterior angle can increase the lumbar lordosis angle, and the cervical anterior inclination can be used as an alternative to pelvic forward inclination to improve the lumbar lordosis angle. Furthermore, the change in head and neck posture can reduce the thoracic kyphosis angle, making it possible to establish a new noninvasive body posture rehabilitation strategy.

Improvement of an exhaust gas recirculation cooler using discrete ribbed and perforated louvered strip vortex generator

This CFD study represents the improvement of cooling performance of Exhaust Gas Recirculation (EGR) by adding newly designed vortex generators inside the engine space of an automobile. The simulation of EGR cooler model was validated comparing with the available data and a reasonable agreement has been observed. A total of twelve different shapes of proposed wing-type vortex generators were numerically investigated to compare the cooling effect of a single VG in the duct. For all the studies, a forward inclination angle of 135° was considered as it is the best inclination angle to get the highest vorticity. Among all, it was found that kite type wing VG provides the best cooling effect. Later, the VGs were arranged in several array configurations with 5 different pitch distances to find the best pitch distance. With the 3mm pitch distance in an array, among twelve different VGs, Gothic type wing VG showed the best performance in terms of cooling performance and 11% cooling improvement rather than a single placed VG was determined. Vorticity and cooling effect were also compared by changing the inlet velocity of the exhaust gas. A comparative study was carried out to highlight that Gothic type wing VG performed best in lowering the outlet temperature. Gothic type VG is 12% and 4% more effective than the discrete ribbed and perforated louvered strip VGs respectively.

Dynamic stability analysis of inclined galloping based piezoelectric energy harvester employing finite element method

A finite element model is proposed for a galloping based piezoelectric energy harvester (GPEH) with an inclined square prism. The absence of any numerical model to capture the effects of inclinations of the bluff body on the performance of GPEH system necessitate the present study. The proposed model is solved in MATLAB environment and validated using the available experimental data. Dynamic stability analysis of the system is done at various vertical inclinations. A substantial decrease in power generation is noticed with the increment of the forward inclination angle. Again, large backward inclinations reduce the power output but perform well compared to forward inclinations. The present work aims to enhance the probability of power generation (GPEH system) in extreme natural flow conditions with negligible structural damage.

Numerical simulation of coupled arc-droplet-weld pool behaviors during compound magnetic field assisted gas metal arc welding

A compound external magnetic field (EMF) can be used to prevent weld bead defects by controlling the metal transfer and arc behaviors during high-speed gas metal arc welding. A unified model containing the filler metal, arc, weld pool, and compound EMF was established to study the effect of the compound EMF on the welding process. The heat and mass transfer among the filler metal, arc, and weld pool under the action of the EMF was numerically analyzed. The simulation results showed that the high-temperature region in the molten pool was reduced and the temperature distribution was more uniform after the EMF was introduced. The speed of the forward liquid metal flow in the front of the molten pool increased due to the forward inclination of the filler metal and arc plasma, and a small metal bulge formed at the leading edge of the molten pool. Because of the periodic swing of the arc and the droplet, the transverse filling of the liquid metal strengthened. The generated additional electromagnetic force inside the weld pool was analyzed, and it had limited impact on the weld pool behavior.

The impact of the foot contact position and cutting angle during cutting on the risk of anterior cruciate ligament injury.

[Purpose] This study aimed to clarify the impact of the foot contact position and cutting angle on the risk of anterior cruciate ligament injury during cutting. [Participants and Methods] Seven healthy males performed cuttings under four tasks by changing the foot contact position and cutting angle. A three-dimensional motion analysis system and force plates were used for taking measurements. The peak vertical ground reaction force and loading rate were calculated. The pelvic, hip, and knee joint angles were measured at the peak vertical ground reaction force. [Results] The loading rate was significantly higher in the lateral foot contact than in the anterior foot contact when the cutting angle was large. The knee flexion angle at the peak vertical ground reaction force was significantly smaller in the lateral foot contact than in the anterior foot contact when the cutting angle was large, similar to the pelvic forward inclination angle, regardless of the foot contact position. [Conclusion] As the cutting angle increased, the knee flexion and pelvic forward inclination angles decreased, resulting in an increase in the loading rate during cutting with the lateral foot contact. Therefore, an increase in the cutting angle can increase the risk of anterior cruciate ligament injury.

ОСОБЕННОСТИ ПРИМЕНЕНИЯ ВЕРТИКАЛЬНОЙ ФРЕЗЫ ДЛЯ ОБРАБОТКИ ПОЧВЫ В МЕЖДУРЯДЬЯХ МАЛИНЫ

When tilling the soil with a vertical-rotary limiter of the raspberry row width, rotating knives perform its transverse transferring. In this regard, it is advisable to fi nd the means to control the process. The study revealed the infl uence of the design parameters of the raspberry row width limiter on the pattern and degree of the lateral displacement of the cross-section of the cultivated soil strip. The authors assessed the intensity of the process of transverse soil redistribution by comparing the positions of the gravity centers of the treated strip cross-section before and after the tillage operation. The studies analyzed medium and heavy loams with a humus content of less than 2.5% and a wide range of variation in moisture content and contamination of the treated strip. With a rotor diameter of about 900 mm, the lateral displacement of the gravity center of the strip cross-section varies within the range of 50…100 mm. The authors found that the lateral displacement control of the soil layer is possible at a constant forward inclination angle of the rotation axis of the knife rotor, which is equal to 18º. This can be done by changing the lateral inclination angle of the specifi ed axis towards the row spacing center in the range between 10 and 20º. As a result, a signifi cant portion of the discarded soil returns to the treated strip surface, minimizing its outside throw-off and eliminating the possibility of injuring the raspberry shoots. The limiter proposed by the authors has a longitudinal baffl e installed at an angle to the vertical with a minimum energy intensity of the process. It helps to maintain the cross-section of the surface of the row spacing of raspberries in a leveled state throughout the entire life of the plantation.possibility of ensuring the maximum propagation range of a non-isothermal supply air jet by angular correction of the fl ow vector at the outlet of the ventilation unit. Based on the theory of free air distribution, the author analyzed and graphically visualized the fl ow trajectories of the supply air from the combined climate control unit with heat recovery in the production room in the range of outdoor temperatures from +10 to –40°C. Given the time period of outdoor temperatures, fl at sections of a three-dimensional graph were built with a step of 10°C in the range from +10 to –30°C. The author found that the maximum service area of the installation is limited by the propagation range of the supply air jet. The area can be increased by changing the direction of the fl ow vector by an angle ranging between 0 and 34°. The value of the inclination angle of the fl ow vector of the supply air jet is determined by the obtained approximation dependency. Considering the regulation of the fl ow vector, the author used the formula of M.Z. Pechatnikov to determine the propagation range of a limited axisymmetric jet. The studies carried out made it possible to establish the relationship between the propagation range of the supply air jet of the installation and the outside temperature, the inclination angle of the fl ow vector, and the theoretical variation range of the inclination angle of the fl ow vector, ranging between 0 and 34°.

Postural phenotype assessment in pupils: a new clinic approach

Introduction: Most of the postural problems originate during puberty, when the body structure is in the process of development and the hormonal release predisposes the differentiated growth between the gender, which can interfere in the posture and balance of the individual. Objective: To analyze the postural phenotypic parameters in school adolescents. Method: A cross-sectional study was carried out in 72 adolescents with age between 10 and 15 years from a public school in the city of Lagarto, Sergipe. The subjects were divided into two groups according to gender (G1: female group; G2: male group) and age subgroups (SB1: adolescents with 10-12 years; SB2: adolescents with 13-15 years), homogeneous in relation to BMI. The research consisted of the collection of anthropometric and clinical data, backpack weighing, static postural evaluation through biophotogrammetry and measurement of stabilometric parameters through a force platform. Results: The individuals presented reduced mobility of the spine and did not overload the school backpack. The prevalence of scoliosis and scoliotic attitudes was 33.32% and more frequentily in the G2. As for the postural angles, the G1 presented knee valgus, hyperextension of the knee and lumbar hyperlordosis, differently, the G2 was characterized with forward inclination of the body, knee flexion, cervical hyperlordosis and thoracic hyperkyphosis. There was no difference in body balance variables between gender, besides the correlation between postural alignment and balance. Conclusion: The study suggests that the phase of corporal development in the school period favors postural phenotypic differentiations.

Numerical simulations of arc plasma under external magnetic field-assisted gas metal arc welding

The arc plasma behavior for gas metal arc welding (GMAW) with an external compound magnetic field was numerically investigated. A three-dimensional finite element model for the external magnetic field (EMF) and a three-dimensional finite volume model for the arc plasma were established. The effects of the EMF on the redistribution of the temperature, fluid flow, pressure, and electromagnetic force in the arc plasma were compared with traditional GMAW under the same welding parameters. The control mechanism of the external compound magnetic field on the arc plasma behavior was analyzed. The results show that the magnitude of the additional electromagnetic force was much lower than that of the self-induced electromagnetic force, but it caused forward inclination and periodic swinging of the arc plasma. When an EMF was applied, the peak temperature decreased, and the temperature distribution was more uniform. The peak pressure was also much smaller than that without an applied EMF.

Effect of changing water depth on muscle activity and motion kinematics during sit-to-stand motion

BackgroundSit-to-stand (STS) movement is a fundamental activity in daily life. Studies have examined the effect of water depth during aquatic exercise; however, no investigation has examined the effect of water depth on STS movements. Research questionThis study examined whether changing water depth affected muscle activity and motion kinematics during the STS movement. MethodsEleven participants performed the STS movement on the ground (land) and at different water depths (1.0-m [deep] and 0.6-m [shallow]) at a self-determined pace. Lower extremity and trunk muscle activity, lower extremity joint angle, and trunk segment inclination angle were measured. Mean muscle activity during STS movement, initial and final postures, and range of motion of each angle was evaluated. Correlations of a normalised time-series pattern of electromyography and motion kinematics measures between land and shallow (land-shallow) and between land and deep (land-deep) were investigated. ResultsThe rectus femoris was more active in shallow than in deep water STS movement but less than that in land STS. Other muscles showed no significant differences between shallow and land STS movement. Correlation of the time series pattern in the tibialis anterior, rectus femoris, and erector spinae muscles was higher in the land-shallow than the land-deep STS. The trunk showed more forward inclination in the shallow STS than the land but less than the deep. Correlation of the time series pattern in the hip joint and trunk inclination angles was higher in the land-shallow STS than in the land-deep STS. SignificanceSTS exercise in the shallow water depth reduced muscle load for the knee extensor but not for other muscles. The muscle activity pattern showed a higher correlation between the land STS and shallow water than deep. Sitting posture becomes upright when the water depth decreases, but a similar motion pattern could be attained regardless of water depth.

Dispersion and upwind-side shear-layer characteristics of forward-inclined transverse jet in crossflow

The effects of the forward inclination of a jet in crossflow on the jet fluid dispersion and upwind-side shear-layer characteristics were studied experimentally in an open-loop wind tunnel. The jet forward-inclination angle θ was varied from 0° to 50°, and the jet-to-crossflow momentum–flux ratio was adjusted between 1 and 2. Short- and long-exposure flow patterns were examined using the laser-assisted smoke flow visualization technique. The binary edge-detection technique was applied to the long-exposure flow images to obtain the jet penetration height. The instantaneous velocities in the upwind-side shear layer of the bent jet were captured by a hot-wire anemometer through a high-speed data acquisition system. The fast Fourier transform method was used to convert the instantaneous velocities from time to the frequency domain. Transverse dispersion of the jet fluids and jet trajectories described by the maximum jet-fluid concentrations were determined using the tracer-gas concentration detection method. The results revealed that at the same jet-to-crossflow momentum–flux ratio, a forward inclination did not significantly influence the flow characteristics and dispersion properties when the inclination angle was smaller than about 12°. At moderate forward inclinations (about 12°–42°), the upstream-side coherent flow structures appeared periodically. The penetration height, transverse width, and dispersion of jet fluids were greater than those of the elevated transverse jet and the slightly forward-inclined transverse jet. At forward inclinations larger than about 42°, the upstream-side coherent flow structures, penetration height, transverse width, and dispersion of jet fluids became the largest when compared with those of the elevated transverse jet as well as the slight and moderate inclination ranges. The jet trajectories in the moderate and large inclination ranges were located at transverse levels higher than those in the slight inclination range and elevated transverse jet due to the appearance of the large upwind-side shear-layer coherent flow structures. The effects of the forward inclinations on the time and length scales of the upwind-side coherent flow structures and the time and length scales of the turbulent eddies were presented and discussed.

Control system based on tracking balance car

For balanced cars, to achieve high-speed and stable operation, two efforts should be made. The first is to make the center of gravity of the car model as low as possible, which is conducive to upright stability. The second is to make the quality as concentrated as possible. Make the vehicle's steering more flexible and reduce the vehicle's moment of inertia. At the same time, the approach angle and departure angle of the car are very important considerations, because the running speed of the car model requires the car model to maintain a certain forward inclination to obtain acceleration. When the car model goes uphill, it also needs to consider the impact of the slope. Hanging the chassis requires a certain distance from the ground while lowering the center of gravity. The battery is the heaviest piece in the entire car. The location of the battery almost determines the height of the center of gravity, the size of the moment of inertia, and the departure angle of the approach angle. In order to reduce the noise of the car to the accelerometer and gyroscope, the sensor should be installed as low as possible.

Assessment of Exposure to Whole-Body Vibration of Dozer Operators Based on Postural Variability

The main aim of this work is to evaluate whole-body vibration (WBV) of dozer operators based on three sitting postures (i.e., with 15° lean forward inclination posture, vertically erect posture with no inclination, and with 15° lean backward inclination posture) in Indian surface coal mines. A seat pad tri-axial accelerometer was used to collect WBV data from six dozer operators for three different sitting postures. Results showed that except for Dozer-1, 2, 4, and 5 operators during lean forward sitting posture and Dozer-4 operator during vertical erected posture, no other dozer operators have exceeded an exposure limit value (ELV) of 1.15 m/s2 in any of the considered sitting postures. Similarly, the vibration dose value (VDV) based on exposure action value (EAV) of 9.1 m/s1.75 has surpassed for all the dozers. But no dozer operator has exceeded an exposure limit value of 21 m/s1.75. The outcome of the study infers that based on “above health guidance caution zone (HGCZ)” for daily vibration exposure, i.e., A(8) measurements, for the operator sitting in lean backward postures the vibration amplification was reduced by 32.89% less compared with lean forward posture and 16.23% less when compared with vertically erected posture. Similarly, based on VDV(8), the exposure to vibration for the lean backward posture was reduced by 33.34% when compared with lean forward posture and 17.11% less when compared with vertically erected posture. Based on the above observation, it is concluded that lean back inclination with a trunk flexion of 15° is a favorable sitting posture, as it exposes the dozer operators to minimum vibration.

Study Regarding the Use of Basketball Elements in the Correction of Kyphotic Postures in Middle Schoolers

Who should observe the deformation of the spine should be the parents or school doctors. Dorsal kyphosis causes an upper body compensation through a forward inclination of the neck and head, and a lower body one through an accentuation of the lumbar curvature. The scapulae get further apart from the thorax through the extension of the trapezius and rhomboid muscles and the shortening of the pectoralis major. The thorax is caved in and the shoulders are brought forward. Physical therapy uses movement for rehabilitation - somatic-functional, motor and psychomotor, or for reeducating the compensatory functions, in the case of the partially reversible or irreversible deficiencies. It is indispensable to medical rehabilitation, mental re-adaptation, professional reeducation and social re-adaptation. Thus, physical therapy refers to the rehabilitation of certain body functions, while prophylactic physiotherapy helps prevent the disorders, regardless of their nature, or even prevent recurrences of and complications from previous disorders.