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In order to carry out the high acceleration impact detection of the internal electronic equipment of the ship and to improve the detection capability of the impact testing machine, the traditional impact testing machine was structurally improved, and a new type of hedge type impact testing machine was designed, and the design parameters and its dynamic characteristics were studied. Firstly, the mechanical structure and control principle of the hedge impact testing machine were introduced, the kinematic model of the equipment was established, and the test action was divided into four processes, which were energy storage, release, collision and braking stages. The mathematical modeling analyses of each stage were carried out, and the maximum energy collision point was determined. Then, solid models were developed and computer simulations were performed using ANSYS software to assess structural stability and impact acceleration predictions. Finally, the dynamic characteristics of the device were examined through several tests, and the location of the collision point and the size of the impact acceleration generated by the device were repeatedly tested at different positions. The acceleration and displacement signals were collected, and the signals were processed by noise reduction filtering and differential calculation to verify the reliability of the device performance. The results of the study show that the structure of the testing machine is simple, easy to operate, and can be tested repeatedly. The dispersion of the distribution data of the collision point from the ideal position in each test is within 30 mm, the data is stable and reliable, which meets the design requirements, and the control method is reasonable. By adjusting the release position of the test bench and the impact table, the size of the acceleration generated by the impact can be changed, and the maximum impact acceleration of about 2 000 g can be generated when releasing at the limit position, which can satisfy the test requirements of various components for impact resistance testing. [ABSTRACT FROM AUTHOR]

Hospital functionality relies not only on the building's structural robustness but also on the seismic performance of its Nonstructural elements, Systems, and Contents (NSC). The objective of this study is to characterize the earthquake‐induced damage to the medical equipment deployed in the full‐scale, five‐story concrete building tested at the University of California, San Diego (UCSD) in 2012 when subjected to Design (DE) and Maximum Considered Earthquake (MCE) levels of demand with Fixed‐to‐the‐Base (FB) support condition. The experimental equipment displacement responses are extracted using the Camera Projection Technique (CPT). Then, sophisticated rolling and sliding models, including instantaneous motion tracking and impact detection are developed to reproduce the equipment behavior obtained from CPT. It was found that CPT was capable of extracting the observed responses and identifying impacts despite the severity of the shaking as long as no significant uplift of the equipment occurred. In addition, both numerical models were capable of reproducing the equipment's displacement trajectories, rotations about the vertical axis (yaw), and impacts as long as no interlocking of the equipment's parts occurred. Moreover, a case study of a partially equipped Emergency Room (ER) was set up to demonstrate that even for low‐intensity motions, the damage to equipment may be significant. Finally, the impact acceleration (a⃗imp$\vec{a}_{imp}$) is proposed as a proxy indicator of damage to medical equipment; however, more functionality tests accompanied by detailed pre‐ and post‐inspections are needed to define robust damage limit states and performance objectives for medical equipment. [ABSTRACT FROM AUTHOR]

Inpavement infrastructure rehabilitation, a comprehensive evaluation of the pavement’s bearing capacity is essential. This paper explores a new attempt for real-time assessment of pavement fracturing effectiveness, combining theoretical and simulation analyses with practical application to four typical pavement structures. The study focuses on analyzing falling weight impact signals to assess pavement load-bearing capacity and fragmentation degree. The findings reveal that: (1) The discrete-continuous coupling method shows that stronger surface and support layers result in higher peak impact accelerations and shorter impact durations. (2) Field data from semi-rigid bases highlight a significant correlation between pre-fracturing resilient modulus and peak impact acceleration, while post-fracturing resilient modulus is closely related to impact duration. (3) In cement pavements, the pre-fracturing deflection corresponds with low-frequency peak values, whereas the post-fracturing deflection aligns with high-frequency peaks. This paper introduces a new approach for real-time pavement fragmentation evaluation, providing a basic reference for the future automation of fracturing techniques.

Runners experience repeated impact forces during training, and the culmination of these forces can contribute to overuse injuries. The purpose of this study was to compare peak vertical tibial acceleration (TA) in trained distance runners on 3 surface types (grass, asphalt, and concrete) and 3 grades (incline, decline, and level). During visit 1, subjects completed a 1-mile time trial to determine their pace for all running trials: 80% (5%) of the average time trial velocity. During visit 2, subjects were outfitted with a skin-mounted accelerometer and performed 18 separate running trials during which peak TA was assessed during the stance phase. Each subject ran 2 trials for each condition with 2 minutes of rest between trials. Peak TA was different between decline (8.04 [0.12] g) and incline running (7.31 [0.35] g; P =.020). On the level grade, peak TA was greater during grass (8.22 [1.22] g) compared with concrete (7.47 [1.65] g; P =.017). On the incline grade, grass (7.68 [1.44] g) resulted in higher peak TA than asphalt (6.99 [1.69] g; P =.030). These results suggest that under certain grade conditions grass may result in higher TA compared with either concrete or asphalt. [ABSTRACT FROM AUTHOR]

Abstract Background Running-related injuries (RRIs) are a prevalent issue for runners, with several factors proposed to be causative. The majority of studies to date are limited by retrospective study design, small sample sizes and seem to focus on individual risk factors in isolation. This study aims to investigate the multifactorial contribution of risk factors to prospective RRIs. Methods Recreational runners (n = 258) participated in the study, where injury history and training practices, impact acceleration, and running kinematics were assessed at a baseline testing session. Prospective injuries were tracked for one year. Univariate and multivariate Cox regression was performed in the analysis. Results A total of 51% of runners sustained a prospective injury, with the calf most commonly affected. Univariate analysis found previous history of injury

More than two decades ago, Marmarou published a valid model for producing diffuse axonal injury (DAI) in rats. Since then, both mild and severe injuries have been obtained by researchers using the original method and a weight of 450 g. However, the diffuse brain injuries produced in rats were only similar to those seen in humans when the rats sustained severe brain injuries. In these cases, rat mortality in the original article was around 50%, and the cause of death was prolonged apnea post‐impact. Rat survival after impact is critical for studying the progression of DAI. In order to explain the cause of death in human victims with cranial trauma who do not show gross brain injury, testing for the presence of DAI is essential. Thus, in order to minimize local and cervical injuries to increase rat survival, attention should be paid to the following aspects: a wider head protector disc should be used, the head of the rat should be elevated at the time of impact, and the foam bed should be soft enough to allow the movement caused by acceleration. With our modified method, rat survival increased by 30% compared to the original model (80% versus 50%). Moreover, 85.7% of rats demonstrated DAI after 24 h of survival. With these modifications, injuries appear in the same locations as in humans; thus, the method is suitable for the study of traumatic DAI in humans. [ABSTRACT FROM AUTHOR]

Background: Running-related injuries (RRIs) are a prevalent issue for runners, with several factors proposed to be causative. The majority of studies to date are limited by retrospective study design, small sample sizes and seem to focus on individual risk factors in isolation. This study aims to investigate the multifactorial contribution of risk factors to prospective RRIs. Methods: Recreational runners (n = 258) participated in the study, where injury history and training practices, impact acceleration, and running kinematics were assessed at a baseline testing session. Prospective injuries were tracked for one year. Univariate and multivariate Cox regression was performed in the analysis. Results: A total of 51% of runners sustained a prospective injury, with the calf most commonly affected. Univariate analysis found previous history of injury < 1 year ago, training for a marathon, frequent changing of shoes (every 0–3 months), and running technique (non-rearfoot strike pattern, less knee valgus, greater knee rotation) to be significantly associated with injury. The multivariate analysis revealed previous injury, training for a marathon, less knee valgus, and greater thorax drop to the contralateral side to be risk factors for injury. Conclusion: This study found several factors to be potentially causative of injury. With the omission of previous injury history, the risk factors (footwear, marathon training and running kinematics) identified in this study may be easily modifiable, and therefore could inform injury prevention strategies. This is the first study to find foot strike pattern and trunk kinematics to relate to prospective injury. [ABSTRACT FROM AUTHOR]

Sprinting on bends demands biomechanical adjustments compared with straight-line sprinting that results in asymmetrical force production in the lower extremities. This study aimed to assess acceleration impacts in the lower extremity and impact transmission when sprinting on bend versus straight lanes. Eight experienced sprinters (age 16.3 ± 1.7 years, mass 58.5 ± 11.4 kg, and height 1.72 ± 0.10 m), specializing in the 100, 200, and 400 m events, ran two bouts of 60 m lane heats at maximum speed on the straight lane and bend lanes one and eight (with radii of 37 and 45.10 m, respectively) of a standard 400 m track. Accelerometers on the tibias and head recorded acceleration impacts. Results revealed higher impact magnitudes in the outside leg during bend sprints compared with the inside leg (p < 0.05). Additionally, bend lanes exhibited higher impact magnitudes compared with the straight lane (p < 0.05). Asymmetrical acceleration impacts were observed during bend sprints, with greater asymmetry compared to straight sprints. However, the distribution of impact forces between the legs did not appear to be influenced by lane radius. This suggests that the specific biomechanical demands of bend sprinting differ significantly from those of straight sprinting. These findings emphasize the need for coaches to account for increased asymmetry and distinct impact patterns when training athletes for bend sprints compared to straight-line sprints., (© 2024 The Author(s). European Journal of Sport Science published by Wiley‐VCH GmbH on behalf of European College of Sport Science.)

Steel sheets are used in various industries such as automotive, aerospace, fuel transport and storage tanks, metal bridges. The issue of impact and penetration in steel sheets has been the main focus of many studies. In this study, laboratory studies of flat and curved steel sheets, as well as reinforced by hardening perpendicular to sheet plate. Under the influence of impact caused by the free fall of the weights are examined. In this study, three radii of infinite curvature (flat sheet), 300 mm and 110 mm were used. This study was conducted for three levels of impact energy (three free fall crashes). Steel sheets used are steel st.12 with dimensions of 220 * 200 mm and 1 mm thicken, fastened in one direction by the fixture and is free on the other side. The material and thickness of the pendentive used are similar to the sheet and have a width of 2 cm. The results also show that the use of hardening causes a slight increase in the acceleration of the sheet and a significant reduction in its permanent deformation. The amount of energy absorbed by the reinforced sheets is slightly less than that of plain sheets. In this research, the sheet with a curvature radius of 110 mm with a pendentive has a better performance than the rest of the sheets.

The purpose of this study was to investigate the effects of prolonged high-intensity running on impact accelerations in trained runners. Thirteen male distance runners completed two 20-minute treadmill runs at speeds corresponding to 95% of onset of blood lactate accumulation. Leg and head accelerations were collected for 20 s every fourth minute. Rating of perceived exertion (RPE) scores were recorded during the third and last minute of each run. RPE responses increased (P < .001) from the start (11.8 ± 0.9, moderate intensity) of the first run to the end (17.7 ± 1.5, very hard) of the second run. Runners maintained their leg impact acceleration, impact attenuation, stride length, and stride frequency characteristics with prolonged run duration. However, a small (0.11-0.14g) but significant increase (P < .001) in head impact accelerations were observed at the end of both first and second runs. It was concluded that trained runners are able to control leg impact accelerations during sustained high-intensity running. Alongside the substantial increases in perceived exertion levels, running mechanics and frequency domain impact attenuation levels remained constant. This suggests that the present trained runners are able to cope from a mechanical perspective despite an increased physiological demand. [ABSTRACT FROM AUTHOR]

Concurrent biofeedback has been demonstrated to be an effective strategy for reducing running-related injuries (RRI) [1–3]. The majority of these RRI are overuse injuries related to impact accelerations [4,5]. However, information regarding impact accelerations is not accessible to the entire population since it requires an accelerometry system. The objective of this study was to investigate the validity and reliability of a new accelerometry system placed directly into the treadmill (AccTrea) and compare it to the traditional system placed directly on the athlete’s body (AccAthl). Thirty recreational athletes with no history of lower body injuries performed two running tests on different days. They ran for 5 min at 10 km/h and at a 0% slope and acceleration impacts and spatiotemporal parameters were collected in two sets of 10 s during the last minute taken in each measurement session. The first session intended to assess the validity of an AccTrea versus an AccAthl, and the second session intended to test its reliability. The results showed that AccTrea is a valid and reliable tool for measuring spatiotemporal parameters such as step length (validity intraclass correlation coefficient (ICC) = 0.94; reliability ICC = 0.92), step time (validity ICC = 0.95; reliability ICC = 0.96), and step frequency (validity ICC = 0.95; reliability ICC = 0.96) during running. The peak acceleration impact variables manifested a high reliability for both left (reliability ICC = 0.88) and right legs (reliability ICC = 0.85), and the peak impact asymmetry demonstrated a modest validity (ICC = 0.55). The valid and reliable results make the AccTrea system an appropriate tool with which to inform athletes about their running mechanics, bringing the laboratory data closer to the running community.

To analyze the maximum acceleration (amax) of a potato colliding with different objects, both experimental test and finite element analysis (FEA) methods were used. Results showed that when potatoes were collided with the single rod, the steel plate and the double rods, the average discrepancies of FEA and experimental test values were 5.3%, 3.95% and 5.04%. The amax increased with the increase of potato drop height, and decreased with the increase of potato mass. Under the same conditions, the amax decreased in turn when the potatoes were collided with the steel plate, the single rod and the double rods. The FEA results showed that the amax in collision with the steel plate was 60.78% to 96.29% higher than that with the double rods. The amax in collision with the steel plate was 53.89% to 83.27% higher than that with the double rods. The amax in collision with the single rod covered with soil was 37.65% and 31.54% lower than that without soil from different drop height or with different potato mass. The research methods and conclusions of this article provided a basis for the analysis of impact mechanics and damage mechanism of potatoes, and contributed to further researches related to solid-like agricultural and food products. [ABSTRACT FROM AUTHOR]

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Several issues concerning shock accelerations production by pneumatic shock machines are considered in the paper. A new method of the required half-sine pulses amplitude ensuring is proposed and theoretically justified. The method is based on the dependence of a shock machine rising height on speed and duration of compressed air supply to pneumatic cylinders that ensure rising and dropping of a test object. A design of the SMU300 pneumatic shock machine used to conduct the method experimental research is considered here. Experimental data have confirmed the effectiveness of the method. An algorithm for setting the design and technological parameters of a shock machine ensuring the required test parameters is proposed. [ABSTRACT FROM AUTHOR]

Suppression of noise from recorded signals is a critically important data processing step for biomechanical analyses. While a wide variety of filtering or smoothing spline methods are available, the majority of these are not well suited for the analysis of signals with rapidly changing derivatives such as the processing of motion data for impact-like events. This is because commonly used low-pass filtering approaches or smoothing splines typically assume a single fixed cut-off frequency or regularization penalty which fails to describe rapid changes in the underlying function. To overcome these limitations we examine a class of adaptive penalized splines (APS) that extend commonly used penalized spline smoothers by inferring temporal adaptations in regularization penalty from observed data. Three variations of APS are examined in which temporal variation of spline penalization is described via either a series of independent random variables, an autoregressive process or a smooth cubic spline. Comparing the performance of APS on simulated datasets is promising with APS reducing RMSE by 48%–183% compared to a widely used Butterworth filtering approach. When inferring acceleration from noisy measurements describing the position of a pendulum impacting a barrier we observe between a 13% (independent variables) to 28% (spline) reduction in RMSE when compared to a 4th order Butterworth filter with optimally selected cut-off frequency. In addition to considerable improvement in RMSE, APS can provide estimates of uncertainty for fitted curves and generated quantities such as peak accelerations or durations of stationary periods. As a result, we suggest that researchers should consider the use of APS if features such as impact peaks, rates of loading, or periods of negligible acceleration are of interest. [ABSTRACT FROM AUTHOR]

Running retraining programs focused on concurrent feedback of acceleration impacts have been demonstrated to be a good strategy to reduce running-related injuries (RRI), as well as to improve running economy and reduce acceleration impacts and injury running incidence. Traditionally, impacts have been registered by mean of accelerometers attached directly to the athletes, which is inaccessible to the entire population, because it requires laboratory conditions. This study investigated the validity and reliability of a new device integrated directly into the treadmill, compared to a traditional acceleration impact system. Thirty healthy athletes with no history of RRI were tested on two separate days over the instrumented treadmill (AccTrea) and simultaneously with an acceleration impact system attached to the participant (AccAthl). AccTrea was demonstrated to be a valid and reliable tool for measuring spatio-temporal parameters like step length (validity intraclass correlation coefficient (ICC) = 0.94; reliability ICC = 0.92), step time (validity ICC = 0.95; reliability ICC = 0.96), and step frequency (validity ICC = 0.95; reliability ICC = 0.96) during running. Peak acceleration impact variables showed a high reliability for the left (reliability ICC = 0.88) and right leg (reliability ICC = 0.85), and peak impact asymmetry showed a modest validity (ICC = 0.55). These results indicated that the AccTrea system is a valid and reliable way to assess spatio-temporal variables, and a reliable tool for measuring acceleration impacts during running.

The characteristics of a treadmill and the environment where it is based could influence the user's gaze and have an effect on their running kinematics and lower limb impacts. The aim of this study was to identify the effect of visual focus on spatio-temporal parameters and lower limb kinematics during treadmill running. Twenty six experienced runners ran at 3.33ms-1 on a treadmill under two visual conditions, either looking ahead at a wall or looking down at the treadmill visual display. Spatio-temporal parameters, impact accelerations of the head and tibia, and knee and ankle kinematics were measured for the final 15s of a 90s bout of running under each condition. At the end of the test, participants reported their preference for the visual conditions assessed. Participants' stride angle, flight time, knee flexion during the flight phase, and ankle eversion during contact time were increased when runners directed visual focus toward the wall compared to the treadmill display (p<0.05). Whilst head acceleration was also increased in the wall condition (p<0.05), the other acceleration parameters were unaffected (p>0.05). However, the effect size of all biomechanical alterations was small. The Treadmill condition was the preferred condition by the participants (p<0.001; ESw=1.0). The results of the current study indicate that runners had a greater mass centre vertical displacement when they ran looking ahead, probably with the aim of compensating for reduced visual feedback, which resulted in larger head accelerations. Greater knee flexion during the flight phase and ankle eversion during the contact time were suggested as compensatory mechanisms for lower limb impacts. [ABSTRACT FROM AUTHOR]

Mechanical loads cause severe damage to perishable agricultural products. In order to quantify the mechanical impact during harvest and postharvest processes, several electronic fruits have been developed. The objective of the work described here was to compare on a laboratory scale different types of impact acceleration recording electronic fruits: Mikras implanted in a real potato tuber as well as in a dummy tuber, IRD, Smart Spud and TuberLog. The acquisition of mechanical impacts was performed using a drop simulator with optional steel or PVC as impact material as well as a processing line simulator. Our results show that drops from 10 cm height on PVC caused similar peak accelerations of Mikras implanted in a real potato or a dummy, IRD and TuberLog. When dropped onto steel however, IRD, TuberLog and Mikras implanted in a dummy recorded higher peak values than Mikras in real potatoes. Impact on the flat side of a tuber led to higher peak values than impact on the apical region. This could be caused by different elastic compliance of synthetic materials as well as material thickness. Running through the processing line simulator TuberLog recorded the most impact; Smart Spud recorded a low number of impacts compared to the other electronic fruits. In all experiments the least sensitive measurements were recorded using Smart Spud.

This paper presents new experimental techniques utilizing a smart debris device for direct measurement of the impact acceleration forces associated with tsunami-borne debris that impact inland structures. The resulting experimental data will lead to advanced predictive capabilities of such forces for use in design guidelines. The measured debris acceleration data were used to calculate impact forces (mass × acceleration). An image processing technique was used to detect the debris impact angle. The debris impact tests were conducted using a disc-shaped smart debris device with masses of 550, 800 and 1000 g. For calculation of the debris force it was found necessary to include the mass of entrained water. The impact acceleration was found to be a function of debris mass, velocity, and contact duration. An equation is developed to allow estimation of the debris velocity for a known distance between the debris pick-up location by a tsunami and the structure. [ABSTRACT FROM PUBLISHER]

A simplified analysis method for large proton exchange membrane fuel cell (PEMFC) stack is proposed to obtain the optimal clamping force if the stack is subjected to an impact acceleration. The PEMFC stack is first simplified to an equivalent stiffness-mass model consisting of a number of springs and point masses in order to get the parameterized structural characteristics. Based on this model, the effects of the structural parameters and impact acceleration on the structural stress of components can be analyzed efficiently. We then discuss how to obtain the proper range of clamping force for a given PEMFC stack according to the structural strength, gas tightness, and non-slippage between the contact components under impact. [ABSTRACT FROM AUTHOR]

Mechanical impact on fresh agriculture commodities may be a criterial issue during mechanical processes such as grading, sorting, conveying, packing or transport. The applications of electronic measuring devices in form of artificial fruits like 'Instrumented Spheres' (IS) are an aid to quantify influences of mechanical impact on the value of fruit, vegetable and potato. Additionally, modelling and simulation of impact on fruits help to identify those influencing parameters. In this study, modelling and simulation runs were performed based on the Finite Element Method (FEM). The relevant parameters modulus of Young, density, mass, fruit dimensions, and dropping test heights were varied for the simulation tests. FEM simulation results were compared with measured acceleration values and impact force values and obtained in a previous work from dropping potato tuber tests, by using a force sensor and an 'Acceleration Measuring Unit' (AMU). The AMU can be implemented into real or artificial fruits to measure the acceleration upon impact. From previous work it was found that, when dropping potato tubers with mass of 100 120 g from 25 cm height onto steel plates, the impact force ranged from 190 to 220 N. Simulations showed that the impact force in similar conditions (mass of 102 113 g and modulus of Young of 2.5 3.5 MPa) ranged from 198 to 242 N, which is in good agreement with the experimental results. When the tuber mass was 190 210 g, the measured impact force varied from 310 to 325 N. Simulations for masses of 199-221 g resulted in impact forces of 306 325 N, again in good agreement with the experimental results. However, AMU acceleration values ranged from 922 932 m/s2 for masses of 100 120 g to 765 824 m/s2 for masses of 190 210 g. Simulations, in similar conditions, provided acceleration values of 1934 2314 m/s2 for masses of 102 113 g (modulus of Young 2.5 3.5 MPa) and ranging from 1497 to 1843 m/s2 for masses of 199 221 g, which are about twice higher than measured, probably due to effects from imperfect fit when the AMU was implanted into the test fruit. [ABSTRACT FROM AUTHOR]

Excessive and prolonged exposure to impact acceleration during running is associated with increased injury rate. Acute use of compressive garments has been speculated to improve attenuation. However, it is unknown how longer interventions of compressive garments influence attenuation in running. 40 runners trained with compressive and placebo stockings for 3 weeks. Perception of comfort, stride parameters (rate, length) and impact acceleration (head and tibial peak acceleration, magnitude, acceleration rate and attenuation) were measured every 5min during a fatigue run (30min at 80% of the individual's maximal aerobic speed). Compressive stockings reduced tibial peak acceleration and magnitude compared to placebo stockings at every minute (p<0.05) except for the initial measurement (p>0.05). Moreover, compressive stockings led to a lower rate of increase in tibial peak acceleration (14 %, p < 0.005) and magnitude (16%, p< 0.001) as a result of the development of fatigue compared to placebo stockings (24% and 26% increase, p = 0.014 and p = 0.003, respectively). Similar perception of comfort was reported for both garments. Training with compressive stockings for 3 weeks reduced impact acceleration and the rate of increase in acceleration compared to placebo stockings. These findings suggest that compressive stockings may play a protective role by reducing impact accelerations during running. [ABSTRACT FROM AUTHOR]

Pounding damage to bridges and buildings is observed in most major earthquakes. The damage mainly occurs in reinforced concrete slabs, e.g. building floors and bridge decks. This study presents the results from pounding of reinforced concrete slabs. A parametric investigation was conducted involving the mass of the pendulums, the relative velocities of impact and the geometry of the contact surface. The effect of these parameters on the coefficient of restitution and peak impact acceleration is shown. In contrast to predictions from numerical force models, it was observed that peak acceleration is independent of mass. The coefficient of restitution is affected by the impact velocity, total participating mass and the mass ratio of striker and struck block. [ABSTRACT FROM AUTHOR]

The impact acceleration curves and impact mechanism of the ball-firing-strength test are analyzed and studied for improving the strength test methods of aiming devices for weapon systems, based on which an integrative impact and vibration system with continuous impact capability and high acceleration value is designed instead of ball firing for strength test of aiming devices of weapons systems. In the strength test of optical sight of a certain small arms, 710 bullets and test cost of RMB 284 thousand have been saved by using this system, which solves the problems of high cost and low efficiency of test to achieve pretty well economic benefit. [ABSTRACT FROM AUTHOR]

Mechanical loads cause severe damage to perishable agricultural products. In order to quantify the mechanical impact during harvest and postharvest processes, several electronic fruits have been developed. The objective of the work described here was to compare on a laboratory scale different types of impact acceleration recording electronic fruits: Mikras implanted in a real potato tuber as well as in a dummy tuber, IRD, Smart Spud and TuberLog. The acquisition of mechanical impacts was performed using a drop simulator with optional steel or PVC as impact material as well as a processing line simulator. Our results show that drops from 10 cm height on PVC caused similar peak accelerations of Mikras implanted in a real potato or a dummy, IRD and TuberLog. When dropped onto steel however, IRD, TuberLog and Mikras implanted in a dummy recorded higher peak values than Mikras in real potatoes. Impact on the flat side of a tuber led to higher peak values than impact on the apical region. This could be caused by different elastic compliance of synthetic materials as well as material thickness. Running through the processing line simulator TuberLog recorded the most impact; Smart Spud recorded a low number of impacts compared to the other electronic fruits. In all experiments the least sensitive measurements were recorded using Smart Spud. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to observe the acceleration responses of the key body segments to the landing impact in selected body positions. 5 young male subjects in 45 experiments were voluntarily exposed to the peak from 4 to 10g and duration from 50 to 80 ms acceleration pulses at 20° supine angle and the peak 10g and duration 50 ms impact at the supine angles from 20 to 60°. The acceleration responses on the dropping platform of the impact tower, the seat, the subject''s head, shoulder, chest and ilium, as well as ECG of the subject were measured. The results demonstrated that the acceleration peaks of these key body segments in the chest-back direction had a highly significant positive correlation with the impact level. But their correlation in the head-foot direction was lower than that in the chest-back direction except that of the head. The acceleration peaks of these key body segments in the chest-back direction had a negative correlation with the supine angle. But the acceleration peaks of ilium in the head-foot direction had a positive correlation with the supine angle, and that of the chest almost bore no correlation. There were nonlinear relations between acceleration peak and supine angle at the head and the shoulder respectively, and the acceleration peaks of the head and shoulder in the head-foot direction reached minimum at about 40° supine angle. It is concluded that the acceleration responses of the key body segments demonstrate different properties between the chest-back direction and the head-foot direction. It is recommended that the angle of the seat back be adjusted about 40° before the spacecraft landing in order to prevent potential head injuries. [Copyright &y& Elsevier]

Abstract: Sand cushions against impact force are widely used for rockfall prevention covers. The objective of this paper is to investigate the effects of the dry density and thickness of a sand cushion on an impact response due to a falling weight likened to a rockfall. A series of laboratory experiments for a decomposed granite soil was executed in the combination of the mass and drop height of the weight. As a result, the impact pressure applied to the soil surface increases with the dry density, but it does not depend on the thickness of the soil. The earth pressure at the bottom of the mold increases with the dry density, and it decreases with the thickness of the soil. Therefore, the transmissibility of the impact pressure decreases rapidly with the thickness of the soil. [Copyright &y& Elsevier]

In this paper, we propose a novel shockproof head gimbals assembly (HGA) structure incorporated with "a balanced-type head suspension" for 0.85-in hard disk drives (HDD5), and investigated its performance on external shock resistance during read/write operations. Experimental drop impact test results confirm that the 0.85-in drive equipped with the new suspension structure is durable over 2000 G (1.0 ms duration) of external shock, ensuring no head slider and/or disk surface damage. According to computer simulation and experimental results, potential shock resistance of more than 2000 G may also be possible with the head actuator itself, which points to its application in cellular phones. [ABSTRACT FROM AUTHOR]