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As a main functional component of rock sheds in rockfall protection projects, traditional sand cushions have shortcomings such as heavy weight and weak buffering capacity. EPS bead-sand cushion can effectively solve these problems, but its buffering mechanism has not been fully revealed. In this study, a series of impact tests were carried out to investigate the performance of EPS bead-sand cushions with different EPS bead contents, and the evolutions of rockfall impact force, penetration depth, earth pressure, and slab vibration under single impact and multiple impacts were comparatively analyzed. The results show that with the addition of EPS beads, the maximum impact force, the peak earth pressure, and the vibration acceleration are significantly reduced. However, the cushion with high EPS bead content is at risk of being penetrated under high energy or multiple impacts, leading to excessive concentration of impact stresses. Furthermore, the EPS beads can alleviate the hardening of the sand cushion under impact through their deformation coordination, but excessive penetration should be prevented in the design of EPS bead-sand cushions. On this basis, combined with traditional sand cushion design theory, an estimation method for the maximum impact force applicable to EPS bead-sand cushion was proposed. The research results can provide a reference for the design and optimization of cushions in actual projects. [ABSTRACT FROM AUTHOR]

Background and Aims: Wheelchairs are a basic necessity for people with disabilities, especially people with physical disabilities. Although conventional wheelchairs have aided the mobility of people with disabilities, they are limited in scope due to physical exhaustion and health problems from sitting in wheelchairs for a long time. This research is important to develop seatback and cushion features for Health Electric Wheelchair Portable IoT-Based wheelchairs, for easy and comfortable mobility for people with disabilities. The development of wheelchairs aims to reduce the negative impact of prolonged immobilization on people with physical disabilities. Methods: Research & Development method. The development stage: 1). The development of pads for Health Electric Wheelchair Portable IoT-Based seatback and cushion needed by wheelchair users; 2). Development of expert-validated Health Electric Wheelchair Portable IoT-Based ergonomics and seatback in accordance with the needs of wheelchair users to improve physical independence; 3). Modify components and equipment for Health Electric Wheelchair Portable IoT-Based cushion and seatback. Results: The result of this development of this wheelchair pays attention to ergonomic design by developing seatback and chair features for Health Electric Wheelchair Portable IoT-Based wheelchairs to provide safety and comfort when using wheel-chairs, especially physical disability. Conclusion: The development of cushion and seatback on wheelchairs can reduce the negative impact of immobilization on people with physical disabilities and is able to provide broad access for users to mobilize on wheelchairs and can adjust to the ergonomics of each user's body. [ABSTRACT FROM AUTHOR]

Pile-slab rockfall retaining wall is a novel passive protective structure designed to intercept falling rocks. It is made up of cantilever piles, pile-intermediate slabs, and cushion layers. This structure features strong terrain adaptability, small footprint, and high interception height, making it applicable in high-risk rockfall areas. However, due to the lack of detailed reports on the ultimate bearing capacity of cantilever piles, guidance for engineering practice is unavailable. This paper first proposes a reasonable thickness for the cushion layer based on the characteristics of the propagation of falling rock impact forces. Then, according to the stress and deformation characteristics of the pile body, theoretical calculation methods of the internal forces and displacements of the pile body are derived using the elastic support cantilever beam model and the Winkler elastic foundation beam model, enabling the automatic determination of design parameters for cantilever pile under falling rock impact. The results indicate that for a rockfall with a diameter of 2 m, impact height of 7.0 m, impact velocity of 10 m/s, and a cushion layer thickness of 1.5 times the rockfall diameter, a double-row triple-limb steel-reinforced 1.5 m x 1.2 m cantilever pile can withstand an impact force of 2.51 x 106 N and impact energy of 565 kJ. For cases with higher falling rock impact energy, it is recommended to prioritize enhancing the bending resistance of the retaining wall. This research provides a scientific basis for disaster prevention and reduction in rockfall-prone areas in the western mountainous regions of China. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To describe the current seating recommendations made by a seating clinic for wheelchair users who presented with a Pressure Injury (PrI) or history of PrI. Retrospective review of electronic medical records of 133 adults who used a wheelchair as their primary means of mobility who had a cushion evaluation during which interface pressure mapping data was documented. Clinicians adjusted 71% of participants' wheelchair cushions, including 49% who received a new cushion, and 37% of participants' wheelchairs. The most common adjustments besides receiving a new cushion were: addition of an underlay, adjusting the inflation of a cushion, and adjustments to the foot or back support of the wheelchair. Forty-five participants only received adjustments (i.e. no new cushion), while 23 participants only received education and feedback rather than equipment modifications. Those 23 participants had significantly lower Peak Pressure Index (PPI) than those who received equipment modifications (mean [95% CI] 76.7 [59.1, 94.3] versus 111.6 [102.1, 121.2] respectively, p = 0.001). The PPI was reduced by an average of 22.5 mmHg from the initial to final seating system amongst those who received modifications ([13.9–31.0], p<.001). The seating clinicians considered interface pressure mapping in their decision-making and effectively reduced interface pressures with their interventions. Cushion replacement is important when someone presents with a PrI. However, adjusting an existing wheelchair cushion and/or seating system provides important additions and alternatives to consider for reducing interface pressure. There is also a role for education about proper use of equipment, weight shifts, and alternate seating surfaces. A cushion evaluation may involve evaluating more than one cushion configuration and using pressure mapping to compare the best options. To address perceived wheelchair cushion issues, posture and positioning should be evaluated and adjusted as necessary, in addition to evaluating the cushion itself. Common positioning modifications include: modifying/adding cushion underlays or inflation and foot and back supports in response to clients' changing postural needs and wheelchair components coming out of optimal position due to wear and tear. Adjustments to the wheelchair and cushion aim to distribute body weight over a larger surface area, reduce pressure at high-risk locations, improve posture, and increase function. These adjustments should consider individual's specific needs and goals, while also being mindful of funding barriers. [ABSTRACT FROM AUTHOR]

Background: The perception of tactile-stimulation locations is an important function of the human somatosensory system during body movements and its interactions with the surroundings. Previous psychophysical and neurophysiological studies have focused on spatial location perception of the upper body. In this study, we recorded single-trial electroencephalography (EEG) responses evoked by four vibrotactile stimulators placed on the buttocks and thighs while the human subject was sitting in a chair with a cushion. Methods: Briefly, 14 human subjects were instructed to sit in a chair for a duration of 1 h or 1 h and 45 min. Two types of cushions were tested with each subject: a foam cushion and an air-cell-based cushion dedicated for wheelchair users to alleviate tissue stress. Vibrotactile stimulations were applied to the sitting interface at the beginning and end of the sitting period. Somatosensory-evoked potentials were obtained using a 32-channel EEG. An artificial neural net was used to predict the tactile locations based on the evoked EEG power. Results: We found that single-trial beta (13–30 Hz) and gamma (30–50 Hz) waves can best predict the tactor locations with an accuracy of up to 65%. Female subjects showed the highest performances, while males' sensitivity tended to degrade after the sitting period. A three-way ANOVA analysis indicated that the air-cell cushion maintained location sensitivity better than the foam cushion. Conclusion: Our finding shows that tactile location information is encoded in EEG responses and provides insights on the fundamental mechanisms of the tactile system, as well as applications in brain–computer interfaces that rely on tactile stimulation. [ABSTRACT FROM AUTHOR]

Culverts are essential under earth embankments to allow watercourses, such as streams and nallas, to pass through without obstructing the natural flow. They help manage floodwaters on both sides of the embankment, reducing water levels and mitigating flood risks. Culverts come in various shapes, including arch, slab, and box configurations, and can be constructed from materials such as masonry or reinforced concrete. Culverts, embedded within earth embankments, are subjected to traffic loads similar to those on the road and must be designed to accommodate these loads. This paper focuses on the structural design and parametric analysis of RCC box culverts, both with and without cushion. Design parameters such as size, invert level, and layout are determined based on hydraulic considerations and site conditions, with the cushion depending on the road profile at the culvert location. The study examines various load cases (e.g., empty box, full box, surcharge loads) and factors such as effective width, braking force, load dispersion through fill, impact factor, and earth pressure coefficient as per IRC codes. It provides a comprehensive discussion on code provisions, design considerations, and justifications for the structural design of RCC box culverts, ensuring they can withstand maximum bending moments and shear forces. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Firat University Journal of Experimental & Computational Engineering (FUJECE) is the property of Firat University Journal of Experimental & Computational Engineering (FUJECE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Piled raft foundations, wherein a small number of connected piles are utilized as settlement reducers, have been widely used for high-rise buildings. Recently, a new technique has been introduced by disconnecting the piles from the raft and inserting a cushion layer between them. In such cases, the piles are considered as soil reinforcement components rather than structural members. To explore the feasibility of utilizing the disconnected piled raft foundation, a series of experimental model tests were conducted to examine the load–settlement behavior and pile load sharing ratio of the connected piled raft (CPR) and disconnected piled raft (DCPR) foundation systems using cushions of different thicknesses and stiffnesses. In addition, ABAQUS 3D finite element analyses were performed to analyze the axial stress along the piles and the bending moments along the raft. The results indicated that the total settlement of the system was minimized significantly when disconnected piles were used. In addition, the disconnected technique provided a significant reduction in the axial stress along the piles and the bending moment along the raft compared with that of the CPR. These findings may be accompanied by economic and environmental benefits. [ABSTRACT FROM AUTHOR]

Precast concrete block slope protection is widely used due to its advantages of easy detection and laying, ease of organization, and the limited time required for construction. In order to prevent the soil or gravel bedding of precast concrete from being subjected to wind and wave pressures, the joints between precast concrete blocks are usually filled with mortar. However, the existing standards do not specify the width or material of the joints. Furthermore, excessively wide mortar joints or shrinkage of the mortar can result in loss, a hollowed-out cushion, and damage to the slope, thus compromising the quality of slope protection engineering. To establish standards for controlling the quality of slope protection seams, this paper designed and conducted a physical model test of precast concrete block revetment seams. By embedding pore water pressure sensors in the cushion layer, changes in the pore water pressure were observed under varying conditions, including different water pore pressure sensor locations, water levels in front of the embankment, and different joint widths. Based on the test results, design standards for joint widths and recommendations for the treatment of joint mortar materials were proposed. After adding different amounts of a calcium oxide–calcium sulfoaluminate composite expansion agent (HME) into a joint mortar material, the paper also carried out a shear test on the contact surface between the joint mortar and the slope protection concrete after adding varying amounts of a calcium oxide-calcium sulfoaluminate composite expansion agent (HME) to the joint mortar material. Following a microporous structure test, recommendations for joint mortar construction treatment were proposed. The results indicate that the pore water pressure of the precast concrete slope protection cushion is closely related to the position of the cushion, the water level in front of the embankment, and the width of the paving seam. When the masonry seam width increased from 0.5 mm to 1 mm and from 1 mm to 1.5 mm, the variation ranges of the pore water pressure were 40–80% and 6–20%, respectively, with the latter being significantly lower than the former. Therefore, in practical engineering, joint treatment should take into account the impact of the cushion position, the water level in front of the dike, and the joint mortar width. Mortar shedding within the range of wave climbing height should be addressed promptly, and joint width should be controlled to below 1 cm as much as possible to effectively prevent damage to the cushion surface. The addition of an expansion agent can improve the bond strength of the concrete and mortar to a certain extent. The study found that an 8% content of the expansion agent resulted in the best mortar bond strength and the densest microstructure. These research findings can serve as a basis for the development of quality control standards for precast concrete slope protection. [ABSTRACT FROM AUTHOR]

Practicing geoengineers and researchers generally consider the load sharing behavior in multi-type pile composite foundation as an important design aspect. On the other hand, due to urbanization, such foundation system in cities will inevitably appear next to supported excavation. This paper discusses the result from relatively largescale indoor experiment conducted to investigate the load sharing behavior of loaded long-short CFG pile composite foundation behind a neighboring rigid retaining wall undergoing rotation around the bottom. It was found that with progression of wall movement, the hidden load from soil displacement was borne by the piles with marked reduction in soil load sharing. At the end of wall rotation, the percentage of long piles’ head load increment needed to arrive at a new static equilibrium was about 12.57~32.22% while the end bearing increased by more than 97%. The consequences on the short piles, however, were manifested with an increasing pile head (13.42%) and toe (28.9%) load for the pile far from the wall whereas the closest one experienced a certain increment up to 15×10-4rad wall rotation and finally the head load and end bearing decreased to 8.28% and 12.63%, respectively. The 3D numerical back analysis conducted using FE software ABAQUS yielded the pile – soil stress ratio lower than the value obtained from the experiment but provided great insight into pile settlement characteristics during wall rotation. [ABSTRACT FROM AUTHOR]

Background: Custom orthoses are becoming more commonly prescribed for upper and lower limbs. They require some form of shape-capture of the body parts they will be in contact with, which generates an STL file that designers prepare for manufacturing. For larger devices such as custom-contoured wheelchair cushions, the STL created during shape-capture can contain hundreds of thousands of tessellations, making them difficult to alter and prepare for manufacturing using mesh-editing software. This study covers the development and testing of a mesh-to-surface workflow in a parametric computer-aided design software using its visual programming language such that STL files of custom wheelchair cushions can be efficiently converted into a parametric single surface. Methods: A volunteer in the clinical space with expertise in computer-aided design aided was interviewed to understand and document the current workflow for creating a single surface from an STL file of a custom wheelchair cushion. To understand the user needs of typical clinical workers with little computer-aided design experience, potential end-users of the process were tasked with completing the workflow and providing feedback during the experience. This feedback was used to automate part of the computer-aided design process using a visual programming tool, creating a new semi-automated workflow for mesh-to-surface translation. Both the original and semi-automated process were then evaluated by nine volunteers with varying levels of computer-aided design experience. Results: The semi-automated process showed a 37% reduction in the total number of steps required to convert an STL model to a parametric surface. Regardless of previous computer-aided design experience, volunteers completed the semi-automated workflow 31% faster on average than the manual workflow. Conclusions: The creation of a semi-automated process for creating a single parametric surface of a custom wheelchair cushion from an STL mesh makes mesh-to-surface conversion more efficient and more user-friendly to all, regardless of computer-aided design experience levels. The steps followed in this study may guide others in the development of their own mesh-to-surface tools in the wheelchair sector, as well as those creating other large custom prosthetic devices. [ABSTRACT FROM AUTHOR]

Settlement of the pile ends in end-bearing rigid pile composite foundations is generally minimal, so only relying on the cushion to coordinate the pile soil deformation may result in insufficient deformation adjustment capacity. Using a deformation adjustor with a specific stiffness on the top of the pile is a method to coordinate pile–soil deformation, and the stiffness value of the deformation adjustor depends on the accurate calculation of soil deformation; however, the calculation of soil deformation is not mature at present. A new deformation adjustor based on strengths used in composite foundations is proposed, in which foam slabs with different yield strengths are placed on the top of the pile to coordinate the pile–soil deformation. Five tests are used to study the mechanical and deformation properties of a composite foundation with a foam slab. The test results show that when the stress at the top of the pile is less than the yield strength of the foam slab, the coordination of the pile–soil deformation mainly depends on the cushion. When the stress of a rigid pile exceeds the yield strength of foam concrete, the foam slab begins to yield and coordinate the deformation of pile and soil, and the settlement coordination ability of a rigid pile composite foundation with a foam slab is significantly improved. Finally, an engineering case is used to simulate the pile–soil stress sharing when the actual settlement is greater than the calculated settlement. The case analysis shows that the pile-top stress can be well controlled by the successive yielding of foam concrete slabs of different strengths, which reduces the influence of settlement error on the pile–soil stress sharing, and further promotes the engineering application of end-bearing rigid pile composite foundations. [ABSTRACT FROM AUTHOR]

Develop an anthropomorphic model cushion rigid loading indenter with embedded sensors (AMCRLI-ES) to assess compression and shear forces at key locations such as trochanters and ischial tuberosities. The sensor design was optimized using finite element analysis. The AMCRLI-ES was designed with the same dimensions as specified in ISO 16840–2 tests. The AMCRLI-ES is divided into eight independent sections, and each section consists of one 3-axis load cell sensor to measure compression and shear forces normal to the compression direction. Six commercial cushions were tested using the AMCRLI-ES with standard ISO 16840–2 testing procedures. Statistical differences were found for energy dissipation between cushions. Statistical differences (p < 0.001) were found in all stiffness values. Test results showed that energy dissipation (ED) was correlated with hysteresis at 500 N with moderate to high Pearson product correlation r = -0.537, p = 0.022. The hysteresis at 250 N did not show a statistical correlation with ED. The AMCRLI-ES demonstrated the ability to measure compression and shear forces at key locations on the cushion including the thigh, trochanter, ischial tuberosity, and sacral area. It provides in-depth information about how the weight was distributed on the cushions. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this experimental study was to compare the ability of polyurethane cushions of three arbitrary selected thicknesses to minimize vibrations transmitted from the wheelchair to its user. Methods: Measurements were made during passive motion on five different surfaces often found in public spaces. Two tests were carried out during the measurements. In the first test, the sensor was located directly on the surface of the wheelchair seat. In the second test, a polyurethane cushion was placed on the seat, on which the measuring sensor was then placed. Results: The study showed that regardless of the surface on which the wheelchair user moves, the threshold defined in the ISO standard for frequencies in the range of 4-40 Hz was exceeded. However, thanks to the use of polyurethane cushions, vibration damping was visible for frequencies ranging from 10 to 40 Hz. The impact of the user's weight on the magnitude of the perceived vibrations was also observed. Conclusions: Studies show that wheelchair users are exposed to whole body vibration that can negatively affect their health. Cushions made of polyurethane seem to be a promising solution to reduce whole body vibration in the frequency range that is burdensome and harmful to human health. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study proposes a high‐resilience foam‐core composite with bionic micro‐interface lattice structure using columnar lattice mold and two‐step foaming technique. This foam‐core composite uses polyamides nonwoven fabrics as the bionic surface layers and polyurethane foam as the bionic core layer. The foam cavity diameter and columnar interface area are adjusted by the polyols content and the column diameter, respectively. Effects of the cavity diameter and the column diameter on the compression resistance, static‐bursting strength, low‐velocity impact, and dynamic cushion efficacy of foam‐core composites are investigated. The results show that compression resistance, bursting strength, and cushion efficacy of the foam‐core composites are all increased by degrees with the cavity diameter when the content of polyols increases. When the cavity diameter was 195 μm, bionic micro‐interface foam‐core composite absorbed 99% low‐velocity impact energy. Existence of bionic micro‐interface lattice obviously improved the static compression and bursting properties. Bionic micro‐interface foam‐core composites with 16 mm‐diameter column have the lower and wider contact force peak compared to pomelo, 8 mm and 12 mm‐diameter column, indicating higher dynamic cushion efficacy. The resulted composite provides an idea of establishing bionic foam‐core cushion composites by foam interface, which is expected to be used as energy absorption material for commercial application. [ABSTRACT FROM AUTHOR]

Ensuring the safety of existing structures is an important issue when planning and executing adjacent new foundation pit excavations. Hence, understanding the stress state conditions experienced by the soil element behind a retaining wall at a given location during different excavation stages has been a key observational modelling aspect of the performance of excavations. By establishing and carrying out sophisticated soil–structure interaction analyses, stress paths render clarity on soil deformation mechanism. On the other hand, column-type soft ground treatment has recently got exceeding attention and practical implementation. So, the soil stress–strain response to excavation-induced disturbances needs to be known as well. To this end, this paper discusses the stress change and redistribution phenomena in a treated ground based on 3D numerical analyses. The simulation was verified against results from a 1 g indoor experimental test conducted on composite foundation reinforced with long and short cement–fly ash–gravel (CFG) pile adjacent to a moving rigid retaining wall. It was observed that the stress path for each monitoring point in the shallow depth undergoes a process of stress unloading at various dropping amounts of principal stress components in a complex manner. The closer the soil element is to the wall, the more it experiences a change in principal stress components as the wall movement progresses; also, the induced stress disturbance weakens significantly as the observation point becomes farther away from the wall. Accordingly, the overall vertical load-sharing percentage of the upper soil reduces proportionally. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mosaic Research is the property of Uludag University, Mosaic Research Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The cushion of a geomembrane surface barrier of a high rockfill dam built on deep overburden is prone to crack and fail because of excessive flexural deformation. This study proposes a geomembrane surface barrier for a high rockfill dam on deep overburden. The proposed geomembrane surface barrier uses polyurethane bonded aggregates as the cushion material. The loading and deformation performance of the barrier system under uniform water pressure was investigated using a self-developed structure model test device. The mechanical and deformation property of each layer of the barrier, and the interaction mode between adjacent layers, were obtained through external videos and internal sensor monitoring. The results demonstrated that the polyurethane bonded aggregate cushion exhibited good adaptability to flexural deformation during the entire loading process and maintained good contact and coordinate deformation with the upper protective and the lower transition layers. The geomembrane surface barrier created using polyurethane bonded aggregates as the cushion material can adapt to the flexural deformation of a high rockfill dam surface on deep overburden. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the effects a cushion has on electrophysiological signals and to identify the important design elements required for manufacturing better therapy cushions. Design/methodology/approach: Four types of attachment cushions were manufactured by changing the shell fiber (cotton or microfiber) and the interlining (synthetic loose fiber or buckwheat). The products were evaluated by 20 healthy individuals (10 stable cushions and 10 unstable cushions). We examined the participants by electroencephalography (EEG) and electrocardiography (ECG). Findings: The authors found significant differences in both EEG and ECG between participants with unstable and stable attachment types. Originality/value: A complex approach to emotional product evaluation was attempted by analyzing differences due to design variables of cushions through subjective evaluation as well as EEG and ECG. [ABSTRACT FROM AUTHOR]

Reinforced soil wall has proved to have excellent impact resistance in engineering, but less attention has paid to their failure process and dynamic response subjected to impact loading. The authors performed model tests and numerical simulations of reinforced soil walls with and without cushion under differential impact loading. The deformation, failure process and impact stress of three retaining walls were mainly analyzed, and the influence mechanism of geosynthetic and cushion on the impact performance of retaining wall were discussed qualitatively. The results showed that the impact deformation of reinforced soil wall with cushion was mainly concentrated on the cushion. The failure process of retaining wall could be divided into two stages: the soil around the impact point of retaining wall was compacted (stage I), a sliding surface formed in retaining wall gradually and retaining wall would failure (stage II). Geosynthetics benefited the sliding surface move back and cushion improved the impact resistance of retaining wall. Furthermore, stress absorption of geosynthetic and cushion was confirmed. The absorption rate of geosynthetic was related to the impact energy positively. The absorption rate of cushion was related to the impact energy positively and related to the thickness of cushion negatively. Engineers can consider the impact energy and the absorption rate of geosynthetic and cushion to design reinforced soil wall with cushion under impact loading. [ABSTRACT FROM AUTHOR]

Understanding the load transfer mechanism and the load settlement behavior of non-connected piled raft foundations with cushion is so complicated. In the present research, based on the assumption of an axisymmetric cylindrical unit cell including pile, subsoil, cushion, and raft, an analytical model is developed and introduced. This model is capable of estimating the transferred vertical stress from raft to piles head and subsoil, compression of cushion, and differential settlement between pile head and subsoil. Also, an experimental test program has been introduced to investigate the behavior of non-connected piled raft foundations and to validate the proposed model. To represent the effectiveness of using non-connected piled raft with different cushion thickness, number, and length of piles measure with the unpiled raft, the load improvement ratio and the settlement efficiency ratio are used. According to the results, the minimum increase in the bearing capacity and the reduction in the settlement of non-connected piled raft to the unpiled raft are 42% and 38% respectively. Also, increasing the cushion thickness increases the differential settlement at the pile head elevation, and for a given number and length of pile, reduced the bearing capacity of the piled raft by 30%. The good agreement of model predictions with the experimental results is verified. The difference between the experimental and analytical values of the cushion compression above the pile head is within an acceptable range. [ABSTRACT FROM AUTHOR]

Questions: Studies in alpine environments have highlighted dominant facilitative effects of cushion species for diversity. Many fewer studies have assessed the effects of cushion shrubs in drier and less cold mountain habitats and how these effects vary within the shrub canopy and with increasing drought stress with exposure and disturbance by fire. Location: A mountain steppe of the Golestan National Park in the semi-arid climate of northeast Iran. Methods: We quantified the cover of understorey species at the center and edge of the canopy of the thorny cushion shrub Onobrychis cornuta and in paired open areas, in north and south exposures and unburned and burned plots, two years after a fire. Soil chemical variables and moisture were measured in treatments. We quantified cushions' center and edge effects on understorey species cover with the Relative Interaction Index (RII). Treatment effects on RII cover were analyzed with generalized linear mixed-effects models (GLMM) and species composition with Correspondence Analysis. Results: In unburned plots, competition for cover was very high at cushion centers and strongly decreased at cushion edges. Exposure stress did not affect competition in unburned plots. Fire slightly decreased competition but only at center cushion shrub position and at south exposure. Species composition was mostly affected by exposure and fire treatments, although there was subtle variation in species composition among patches due to fire. Cushion position, fire and exposure treatments affected soil moisture and chemical variables, but soil changes did not explain cushion effects on understorey cover and their variations along treatments. Conclusions: The effects of the cushion shrub were highly negative and in particular at cushion center, likely due to interference and competition for light in a dry and not too cold environment. Fire only slightly decreased competition in the short term, likely due to the delayed response of understorey species to disturbance induced by fire. [ABSTRACT FROM AUTHOR]

A sustained quasi‐dipolar magnetic field between the current sheet outer edge and the magnetopause, known as a cushion region, has previously been observed at Jupiter, but not yet at Saturn. Using the complete Cassini magnetometer data, the first evidence of a cushion region forming at Saturn is shown. Only five examples of a sustained cushion are found, revealing this phenomenon to be rare. Four of the cushion regions are identified at dusk and one pre‐noon. It is suggested that greater heating of plasma post‐noon coupled with the expansion of the field through the afternoon sector makes the disc more unstable in this region. These results highlight a key difference between the Saturn and Jupiter systems. Plain Language Summary: The presence of the moons Enceladus and Io provide an internal source of plasma to the magnetospheres of Saturn and Jupiter, respectively. This, coupled with their rapid rotation rates (approximately 10 h), radially stretches the magnetic field at the equator away from a dipole configuration to what is known as a magnetodisc. However, this structure can break down at large distances where the magnetic field can no longer contain the plasma and the field becomes dipolar, known as a "cushion region." This has previously been observed at Jupiter, but not at Saturn. We present the first evidence of a cushion region forming at Saturn. We find only five examples, showing it to be rare, with four at local time dusk and one pre‐noon. The dusk cushion we have observed could be due to asymmetric heating of plasma in the Saturn system, as well as the changing magnetic field configuration as the plasma moves through noon into a less compressed region, resulting in disc instabilities. These results show a key difference between the Saturn and Jupiter system, where at Jupiter the cushion is a result of large‐scale reconnection in the tail and return flow. Key Points: The first example of a cushion region at Saturn is identifiedOnly five examples of a cushion are identified, showing this phenomenon to be rare, with four at dusk and one at dawnThe dusk cushion could form due to the greater heating of plasma and the expansion of the field in the afternoon sector [ABSTRACT FROM AUTHOR]

Study aim: The aim of this study was to determine the optimal angle for maximizing pressure distribution in two types of wheelchairs (tilting and reclining) while using a ROHO cushion, which offers relatively effective pressure distribution. Material and methods: This study enrolled 28 male and female college students who understood the purpose of the study and agreed to participate. This study aimed to determine the optimal angle for tilting and reclining wheelchairs when using a ROHO cushion at angles of 10°, 20°, and 30° with tilted wheelchairs and 90°, 110°, and 130° with reclining wheelchairs. Results: The analysis showed that an improved pressure distribution when a tilting wheelchair was used versus a reclining one. A reclining position of ≥110° and a tilt angle of ≥20° led to significant pressure-reducing effects. Conclusion: The results of this study will help wheelchair users or their guardians to select the optimal wheelchair angle when changing their posture to prevent bedsores. Although no slippage was observed in our study, it is important to remember the proper back position to prevent unnecessary slippage. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Anterior cervical discectomy and fusion is considered as a standard procedure for treating cervical degenerative disc disease. This retrospective study aimed to analyze the radiographic outcome of using a novel cushion titanium cage (Baui Z-Brace Dynamic Fusion Cage). Methods: Fifty-seven patients who received either single-, double-, or three-level interbody fusion surgeries were enrolled. Data from initial status after surgery and postoperative follow-ups for five years were obtained. The patients were divided into three groups according to different levels of cage implantation: 1-level (n = 2 7), 2-level (n = 2 5), and 3-level (n = 6). Follow-up time and fusion rate of radiographs were subjected to evaluation. Results: The lateral view of plain radiographs manifests no evident cage subsidence (> 3 mm) and dislodgment in 1-, 2-, and 3-level cage implantation. The follow-up time is three years in 1-level and two years in 2- and 3-level. The CT scans at the final follow-up among different levels of cage implantation manifested bony fusion. The measurement of the Hounsfield unit indicates the bone growth inside the cage compared with control case, demonstrating solid bony fusion among groups at the final follow-up. Conclusions: The data confirm that the specialized Z-shaped structure of the cushion titanium cage may provide the interfragmentary motion stimulating innate bony fusion for sustained improvement. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Culverts are often required under earth embankment to allow for the crossing of a watercourse, like streams, to prevent the road embankment from obstructing the natural waterway. The opening of the culvert is determined based on the waterway required to accommodate the design flood, whereas the thickness of the culvert section is designed based on the loads applied to the culvert. From the previous literature review, it is noted that the effect of haunch on the stresses of the culvert was not studied. Therefore, this research focuses on the impact of using haunches on the economy of the culvert design. This paper studies some design parameters of box culverts, such as the thickness of the haunch, the coefficient of earth pressure, the thickness of box culvert, and depth of fill on the top slab. The objectives show the effect of haunch on the stresses of the box culvert. The study investigated the variation in stresses and the cost comparison made for different width of the box culvert. The percentage reduction in the cost of culvert based on the presence of haunch is presented. At last, several significant conclusions are given based on numerical results as the presence of haunch is the best solution for decreasing the values of stresses from the economic point of view. [ABSTRACT FROM AUTHOR]

Purpose: Pressure injuries are a complication due to spinal cord injury. The objective of the study is to compare the pressure distribution in the wheelchair seat of subjects with spinal cord injury using 3 pads (Roho®, Varilite® and Jay®). Methods: Pressure analysis was performed on 10 participants in two situations: (a) the participant sitting in static posture and (b) with the wheelchair being used for locomotion. Results: In the static position: Jay® showed the best rates for average pressure and also the contact area, the Roho® had the lowest average for the peak pressure. During the wheelchair moving, Jay® showed the best average pressure, Roho® had a lower average for peak pressure and Varilite® provided a highest means for the contact area of the buttocks and thighs. Conclusions: The use of appropriate cushion is an effective measure in people with spinal cord injury. Pressure injuries are a complication due to spinal cord injury. Study to compare the pressure distribution in the wheelchair seat of subjects with spinal cord injury is important to minimize the injuries resulting from pressure injuries. The comfort resulting from the use of the cushion suited to the demands of the subjects with spinal cord injury is fundamental for the process of rehabilitation and social participation of the people affected. Understanding and minimizing pressure points can contribute to the appropriate rehabilitation process. [ABSTRACT FROM AUTHOR]

Results of calculations for determining the critical angular speed of saw cylinder are presented in the paper with account of a mass of raw material roll in the form of an ideal incompressible fluid. Comparison of the values of critical angular speed of a saw cylinder with an analytical method, not accounting the load from the raw material roll, made it possible to establish a difference in the calculations up to 3.5%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mechanical & Electrical Engineering is the property of Mechanical & Electrical Engineering Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, electric vehicles are developing rapidly in automotive industry. When involved in accidents, if the batteries of electric cars break, it is likely to cause a short circuit and start a fire. Aimed at this issue, a car battery protection device based on torsion spring has been designed. The car battery protection device can deform in a particular pattern in a collision accident. Impact energy of the accident is absorbed by the deformation, which can significantly reduce impact force on the batteries. Meanwhile, based on the principle of maximum energy absorption, some crucial parameters of the device can be determined. Furthermore, an impact simulation conducted on ANSYS software shows that maximum safety factors can be obtained when the material of car battery protection device is carbon steel. The analysis of 'safe space' in the car battery protection device shows that the device can prevent battery damage effectively in general circumstances, which means the reliability of the device has been verified. Therefore, when applied to electric vehicles, the car battery protection device, which can prevent secondary accidents, significantly improves the vehicle security in accidents. [ABSTRACT FROM AUTHOR]

During everyday operations with tractors, drivers are exposed to harmful effects of various factors. In addition to unfavourable temperature and humidity, dust and noise, one of the factors harmful to driver's health is vibrations. They come from the tractor engine and from the roughness of the ground and are transferred to the cab and through the seat to the body of the driver. In case of high level magnitude vibrations and a long period of exposure to them, many health problems occur. The harmful effect of the vibrations is especially obvious in older models of tractors. High intensities of vibrations (above permitted limits) were found during the measurements of vibrations at the driver seat in such tractors. This study is an attempt to reduce the vibration levels using various vibration-absorbing components, such as cushions, at driver's seat. The results of the measurements showed that the vibration levels were significantly lower in comparison to original seats. [ABSTRACT FROM AUTHOR]

Little is known about the changes in moisture that occur at the body-seat interface during sitting. However, as increased moisture can add to the risk of skin damage, we have developed an array of MEMS (Micro-Electro-Mechanical System) humidity sensors to measure at this interface. Sensors were first evaluated against traceable standards, followed by use in a cross-over field test (n = 11; 20 min duration) using different wheelchair cushions (foam and gel). Relative humidity (RH) was measured at the left mid-thigh, right mid-thigh and coccyx. Sensors were shown to be unaffected by loading and showed highly reliable responses to measured changes in humidity, varying little from the traceable standard (<5%). Field-test data, smoothed through a moving average filter, revealed significant differences between the three chosen locations and between the gel and foam cushions. Maximum RH was attained in less than five minutes regardless of cushion material (foam or gel). Importantly, RH does not appear to distribute uniformly over the body-seat interface; suggesting multiple sensor positions would appear essential for effectively monitoring moisture in this interface. Material properties of the cushions appear to have a significant effect on RH characteristics (profile) at the body-seat interface, but not necessarily the time to peak moisture. [ABSTRACT FROM AUTHOR]

Expansive soils undergo alternate swelling and shrinkage with changes in the moisture regime. As a result, structures founded in these soils undergo distress. Among the several techniques available to mitigate the problem, CNS layer technique is the one commonly adopted. Since this technique has certain limitations, an alternative method was tried with stabilized blast furnace slag for better results. Granulated blast furnace slag is one of the major by-products of steel plant industry. The disposal of it poses a big problem which, if not solved, causes environmental pollution. Detailed laboratory studies were carried out on this material to investigate its suitability as a construction material. Experiments were conducted to study the effect of the cement content as well as the cushion thickness on the heave of the expansive soil bed. Expansive soil for the study was collected from a depth of 1.5 m in order to see whether it contains no organic matter. The liquid limit is 73% and the plasticity index is 45%, which are very high and show that the soil has high potential for undergoing volume changes. A free swell index of 150% shows that the soil has a high degree of expansiveness. The expansive soil was compacted to its MDD at OMC and above it cement-stabilized blast furnace slag in the form of a cushion compacted to MDD at OMC was placed and the resulting heave was measured. Cement content, varying from 2% to 10%, with increments of 2% by weight, was added to GBS in dry condition and mixed thoroughly. Then, water corresponding to OMC was added and the layer placed above expansive soil bed and compacted to its MDD. Experiments were conducted for different thickness ratios of soil (ts) and cement-treated GBS (tc) given by tc/ts = 0.25, 0.5 and 0.75. Studies were also conducted using cement-stabilized ground granulated blast furnace slag cushion in the same way as mentioned above. It was found that granulated blast furnace slag cushion, stabilized with cement, was effective in arresting heave of expansive soils. [ABSTRACT FROM AUTHOR]

In order to quantitatively study the seismic absorption effect of the cushion on a superstructure, a numerical simulation and parametric study are carried out on the overall FEA model of a rigid-pile composite foundation in ABAQUS. A simulation of a shaking table test on a rigid mass block is first completed with ABAQUS and EERA, and the effectiveness of the Drucker-Prager constitutive model and the finite-infinite element coupling method is proved. Dynamic time-history analysis of the overall model under frequent and rare earthquakes is carried out using seismic waves from the El Centro, Kobe, and Bonds earthquakes. The different responses of rigid-pile composite foundations and pile-raft foundations are discussed. Furthermore, the influence of thickness and modulus of cushion, and ground acceleration on the seismic absorption effect of the cushion are analyzed. The results show that: 1) the seismic absorption effect of a cushion is good under rare earthquakes, with an absorption ratio of about 0.85; and 2) the seismic absorption effect is strongly affected by cushion thickness and ground acceleration. [ABSTRACT FROM AUTHOR]

A small, non-controlled evaluation set out to assess the effectiveness of the Airospring AS200 cushion in preventing the development of pressure ulcers in patients in nursing/care home and hospice settings. Ten patients, assessed as being at low-to-medium risk of pressure ulceration, were recruited into the evaluation; the mean age was 82.7 years. Of these, nine were living in nursing/care homes and one in a hospice. The follow-up period was 4 weeks for nursing/care home patients and 2 weeks for the hospice patient. Seven patients had a cognitive impairment. All patients were chairfast or had limited mobility. Of the 10 patients, one (from a care home) was withdrawn from the evaluation at week 2 because of a deterioration in her condition, although her skin remained intact. At the end of the follow-up period, the sacral skin was still intact in seven patients out of the nine remaining, but one patient developed persistent signs of blanching erythema. These preliminary results indicate that this pressure-redistributing cushion is largely effective in preventing pressure ulceration. [ABSTRACT FROM AUTHOR]

The Prestressed Concrete Pipe (PCP) pile-composite foundation was initially employed in the foundation of a culvert in the ancient Yellow River of China. To analyze the reinforcement effect of the foundation, a composite foundation composed of PCP piles was investigated with field tests and numerical simulations. A static load test was conducted to investigate the stress and deformation of the PCP pile-composite foundation, and a finite element model under three-dimensional (3D) axisymmetric conditions was developed to simulate the stress and deformation of the foundation. The Finite Element (FE) model used a nonlinear constitutive model for the soil, cushion and pile-soil interface. The results of the numerical simulations correspond with the load sharing, stress and displacement results of the static load test and indicate that the soil stress is primarily compressive. The cushion reduces the difference in settlement between the middle region and the side region of the bearing plate and increases the bearing capacity of the PCP pile-composite foundation. The stress of the pile significantly varies in the upper 1 m. The pile-soil load-sharing ratio increases with an increase in external load. This paper is expected to be useful for scientific research and efficient applications of PCP pilecomposite foundations. [ABSTRACT FROM AUTHOR]

In this article, the mesh fabric and porous filler are combined with polyurethane (PU) foam to fabricate sound-absorbing composite boards with puncture resistance and cushion protections, after which sound absorption and static puncture resistance are improved. Effects of fillers (vermiculites and perlites) content and mesh opening ratio on sound absorbing, puncture resisting and cushioning properties are explored respectively. Result shows that, mesh fabric improves the low-frequency coefficients, and also increases the puncture resistance by 2 times and 1.5 times for 2-mm-diameter and 4.5-mm-diameter probes penetrations. Absorption peak shifts to the lower frequency with increase of fillers content and mesh opening, but static puncture resistance against 4.5-mm-diameter probe decreases with mesh opening ratio. The fabricated composite foam boards can absorb 90 % of impact energy when compounding with 10 wt% vermiculite fillers and 45 % opening fabric, which shows the favorable cushioning protection. This mesh-reinforced composite foam boards can be applied as protective compartment walls whatever in gerocomium, women and children care center, kindergarten or karaoke TV room. [ABSTRACT FROM AUTHOR]

This article highlights the potential of the application of the cause-effect model for the ergonomic evaluation in the field of cushions. User involvement in the prescription and development of assistive devices have been identified a key aspect for positive interventions, although the reality is that we lack of systematic approaches and examples of best practices. The potential benefits are identified for the development of new products and in the prescription process. Additional research would be necessary to better link the characteristics of the cushions and users with the biomechanical and physiological performance of the interface cushion-user and the consequences measured in health, user perception and activity performance. This article shows examples of the relationship in this three levels from the point of view of the user perception. [ABSTRACT FROM AUTHOR]