270 research outputs found
Cushion hypothesis and credit risk: Islamic versus conventional banks from the MENA region.
No full textConventional banks are 'indirectly' allowed to take more risk under the shadow of sovereign guarantees. Banks commit moral hazards as any major banking crisis will be 'cushioned' by deposit insurance and bailed out using the taxpayer's money. This study offers an alternative explanation for the determinants of banks' credit risk, particularly those from the Islamic regions. Although conventional banks and Islamic banks may share state and social cushioning systems, Islamic banks are strictly prohibited by moral and religious principles from gambling with depositors' funds, even if there is a cushion available to bail them out. However, banks belonging to collective societies, such as those in the MENA area, may be inclined to take more risks due to the perception of having a larger safety net to protect them in the event of failure. We analyse these theoretical intersections by utilising a dataset consisting of 320 banks from 20 countries, covering the time span from 2006 to 2021. Our analysis employs a combination of Ordinary Least Squares (OLS), Fixed Effects (FE), and 2-step System-GMM methodologies. Our analysis reveals that Islamic banks are less exposed to credit risk compared to conventional banks. We contend that the stricter ethical and moral ground and multi-layer monitoring system amid protracted geopolitical and post-pandemic crises impacting Islamic countries contribute to the lower credit risk. We examine the consequences for credit and liquidity management in Islamic banks and the risk management strategies employed by Islamic banks, which can serve as a valuable reference for other banks. [Abstract copyright: Copyright: © 2024 Abdeljawad et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Designing a shaped seat-pan cushion to improve postural (dis)comfort reducing pressure distribution and increasing contact area at the interface
No full textRemaining seated for extended periods increases the risk health issues and discomfort perception. Consequently, the seat-pan design is crucial and could be mainly influenced by two factors: pressure distribution and seat contour. For seat pan discomfort, the lower average pressure is accompanied by less discomfort. Moreover, a seat contour with a large contact area is correlated with more comfort. Thus, a shaped cushion had been accurately designed (Virtual Prototype) and realized (Physical Prototype) aiming to translate the pressure distribution due to interaction between seat and buttock in a geometric shape, suitable for the international population (including P5 females and P95 males). With this shape, the pressure should be more uniform and lower, the contact area at interface bigger, and the perceived comfort higher. Both Virtual and Physical Prototype design had been described in this paper through a repeatable and straightforward approach. Also, experiments had been performed to validate the hypothesis through a comparison with a standard flat cushion. Results showed the goal of the design had been reached: the shaped cushion scored less pressure distribution and higher contact area than the flat cushion.Materials and ManufacturingMechatronic Desig
Analytical Studies of the Lift and Roll Stability of a Ram Air Cushion Vehicle
No full textDOT-FR-307A ram air cushion vehicle (a type of ram wing) is described schematically and compared with a conventional air cushion vehicle design. The nonlinear equations for the flow in the cushion region are derived. A review is made of the most recent literature on the subject of wings operating in a rectangular channel, and an approximate solution is developed which shows the relative effects of momentum and viscosity on the pressure distribution. Several analytic solutions are presented which show the effect of a small roll angle on the flow pattern; equations for the rolling moment coefficient are also obtained. It is recommended that future efforts be aimed at developing proper numerical techniques which can solve the nonlinear flow relations and that recent experimental efforts to obtain the lateral stability coefficients be continued and expanded. (Author
The Postcricoid Cushion: An Unusual and Surgically Treatable Cause of Infant Aspiration
No full text© The Author(s) 2020. Objectives: To highlight the importance of recognizing the postcricoid cushion as a surgically treatable cause of newborn aspiration in select cases unresponsive to conservative measures. Methods: A retrospective review was performed on a single case of neonatal aspiration at a tertiary care pediatric hospital. Results: Resolution of aspiration was achieved in an otherwise healthy six-week old term infant following ablation of a postcricoid cushion using microlaryngeal instrumentation and coblation. Prior airway and swallowing evaluations, along with a trial of reflux therapy and pacing of feeds, preceded the surgical excision, successfully avoiding gastrostomy tube placement. Conclusions: Otolaryngology consults for neonatal dysphagia and aspiration are challenging. The postcricoid cushion is considered an anatomic variant that can engorge with crying. When large, it can prevent feeds from entering the esophagus and lead to pooling and aspiration. The postcricoid cushion is evident on flexible fiberoptic laryngoscopy, but without a vigilant eye may be easily overlooked. This single case report suggests that surgical ablation may be effective management in select cases after ruling out concomitant aerodigestive pathology and neurodevelopmental causes of aspiration and only after conservative therapy has failed. A video demonstrating the surgical ablation is included
Objective comparison of two cushions: pressure distribution and postural perceived discomfort
No full textDesigning seats is crucial not only for health issues but also for the (dis)comfort perception. The seat pan design could be mainly influenced by two factors: pressure distribution and seat contour. For seat pan discomfort, the lower average pressure is accompanied by less discomfort. Moreover, a seat contour with a large contact area is correlated with more comfort. So, a shaped seat pan was accurately realized following the buttock-thigh shape of an international population (including P5 females and P95 males). For the comfort assessment, a comparison was made between this shaped seat pan (shaped cushion) and a standard aircraft seat pan (flat cushion). Twenty-two internationalparticipants (11 males and 11 females, with BMI between 16 and 30) took part in the blind experiment assuming six different postures. Subjective data were gained from questionnaires, whose results showed that the shaped cushion is better in terms of perceived postural comfort. Also, 64% of participants chose the shaped cushion as a preferred cushion because it was more comfortable and suitable for the buttock shape. Objective data were gathered with a pressure mat, and results showed a higher contact area and lower mean pressure distribution for shaped cushion. Significant correlations were calculated between objective and subjective data with Spearman Correlation coefficients.Mechatronic DesignMaterials and Manufacturin
Processed measurement data of shear stresses distribution in the cushion filled with magnetorheological (MR) fluid
No full textProvided here csv files cointain processed data gathered during experiments described in the article entitled: Design and Optimization of a Magnetic Field Exciter for Controlling Magnetorheological Fluid in a Hybrid Soft-Rigid Jaw Gripper. https://doi.org/10.3390/en16052299The data are under Creative Commons License CC BY. It is though recommended to manipulate along with the author to fully understand the outcomes. If you have any questions do not hesitate to contact: marcin.bialek@put.poznan.plThis research was funded by the National Science Centre, Poland grant number: 2021/41/N/ST8/02619. https://ror.org/03ha2q922 DESCRIPTION:The dataset provides the outcome of the finite element study of the shear stress distributions in the magnetorheological fluid (MRF) when subjected to magnetic field excitation. Different dimensions of permanent magnet, yoke, and air gap were examined. The work focused on optimizing the magnetic circuit of a field exciter used to control magnetorheological fluid (MRF) in a hybrid soft-rigid jaw gripper. Specifically, it addresses the sealing of MRF within a cushion made of thermoplastic polyurethane (TPU). A parametric numerical model of the magnetic field exciter was developed, allowing for the analysis of over 4600 variations of the magnetic circuit. The model, implemented in Ansys Electronics Desktop 2020 finite element method (FEM) package, determines the shear stress distribution in the MRF inside the cushion. The research focused on finding magnetic circuit dimensions that result in the desired shear stress distribution within the MRF. Both undeformed and deformed cushion geometries, caused by axial plunging of the pin, were analyzed. The evaluation criteria include achieving the highest possible shear stress value and ensuring its uniform distribution within the specific cross-sectional area of the MRF cushion. The main objective was to design a magnetic field exciter suitable for jaw pads in a gripper that utilizes MRF cushions.MR fluid applied: LORD MRF-140CG ---------------------------------------- FILES: 1. "processedDataset__not_pressed_2mm.csv" - This file contains measurement data along a section parallel to the bottom of the cushion at a height of 2 mm. The cushion is in its undeformed state - not pressed. 2. "processedDataset__pressed_2mm.csv" - This file contains measurement data along a section parallel to the bottom of the cushion at a height of 2 mm. The cushion is in its deformed state - pressed. 3. "processedDataset__pressed_6-4mm.csv" - This file contains measurement data along a section parallel to the bottom of the cushion at a height of 6.4 mm. The cushion is in its deformed state - pressed. For proper interpretation, please refer to the images provided in the Readme files. ---------------------------------------- COLUMNS: gm [mm] - Thickness of the permanent magnet in mm. kj [] - The ratio of the width of the yoke with respect to the sum of the width of the yoke and the air gap. The percentage value expressed as a decimal fraction. kpm [] - The ratio of the diameter of the permanent magnet with regard to the diameter of the entire magnetic field source 23.7 mm. The percentage value expressed as a decimal fraction. pos_Z [mm] - Distance of the face of the magnetic field source to the base of the cushion in mm. Expressed as "z" in the picture below. Distance [mm] - Distance of the cross section measurement segment in mm. Expressed as "r" in the picture below. TauB [] - The value of shear stress occurring in the cross-section in kPa.</p
Determining the mechanisms causing the hydraulic damping during ship berthing: Comprehending the water cushion effect
No full textWhen a large ship enters a port the vessel is navigated by the pilots instead of the captain due to safety reasons. The final part of the berthing manoeuver is the most critical and consists of the vessel moving laterally towards the quay wall. At this point the vessel does not use its own propulsion force anymore but is pushed by the tugboats. During this lateral berthing manoeuver a resistance force can be noticed counteracting the lateral manoeuver to the quay which acts as hydraulic damping. A large force is needed to overcome this hydraulic damping which is known as the water cushion effect. There are a handful of circumstances that are suspected to enhance the effect of hydraulic damping, but a substantiated conclusion is not yet drawn. To determine the mechanisms causing the hydraulic damping during ship berthing, field experiments in the Port of Rotterdam are carried out and analysed. In addition, a one-dimensional theoretical model is developed to simulate the field experiments and investigate the flow behaviour around a berthing ship.Civil Engineering | Hydraulic Engineerin
Processed measurement data of the experimental study of the cushion stiffness - a component of a hybrid soft-rigid gripper jaw
No full textDESCRIPTION:The dataset consists of measurements of experimental studies of stiffness during plunging the pin into the cushions (soft-rigid robotic jaw fignertip) and soft-rigid robotic jaw (Fig. 1).The measurement system consists of a Panasonic HG-C1100/HL-G112 laser distance sensor and a HBM U9C force sensor mounted on a linear actuator with a stepper motor (Fig. 2).Studies were conducted for different fillings and cushion geometries (Fig. 3, "dataset_1.csv"), as well as for two different springs in the jaw mechanism (Fig. 4,"dataset_2.csv").LICENSE:The data are under Creative Commons License CC BY. It is though recommended to manipulate along with the author to fully understand the outcomes. If you have any questions do not hesitate to contact: marcin.bialek@put.poznan.plThis research was funded by the National Science Centre, Poland grant number: 2021/41/N/ST8/02619. https://ror.org/03ha2q922FILES:"dataset_1.csv" - processed measurement data obtained during the experiment - cushion stiffness measurement"dataset_2.csv" - processed measurement data obtained during the experiment - measuring the reaction of the jaw with an MR fluid filled cushion and a spring-permanent magnet mechanism.For proper interpretation, please refer to the images provided below.COLUMNS in "dataset_1.csv": - Fingertip[-] - type of the cushion determined by its filling, which was placed on the fingertip (please check the table below for more details); - Sample[-] - sample number for each object configuration; - Time[s] - the measurement time at which the force was recorded; - PosSM[] - the set position of the linear drive moving the force sensor; - Distance[mm] - the value of the displacement of the plunger (force sensor), measured with a Panasonic sensor HG-C1100/HL-G112; - Force[N] - the value of the force exerted by the plunger (force sensor) into the cushion, measured with HBM U9C.COLUMNS in "dataset_2.csv": - Spring[-] - type of the spring determined by its parameters (please check the table below for more details); - Sample[-] - sample number for each object configuration; - Time[s] - the measurement time at which the force was recorded; - PosSM[] - the set position of the linear drive moving the force sensor; - Distance[mm] - the value of the displacement of the plunger (force sensor), measured with a Panasonic sensor HG-C1100/HL-G112; - Force[N] - the value of the force exerted by the plunger (force sensor) into the cushion, measured with HBM U9C.</p
Assessing the ability of filtering unwanted sound pressure peaks via a Meta Cushion during pile driving of a monopile: An analysis using small-scale testing: Saving lives of marine life during off-shore wind turbines installation
No full textOne of the biggest challenges of the century is the fight against global warming. In all sectors people are doing their best to reduce their carbon footprints and their impact on the environment. In the energy sector this is done by making use of renewable energy sources (RES), such as wind turbines, instead of fossil fuels. This transition to RES and the growing demand of energy results in extensive off-shore wind farms containing large wind turbines. During the installation of these wind turbines, the monopile (MP) foundation is driven into the seabed using an impact hammer, which dissipates a high amount of energy into the water in the form of sound pressure waves. The intensity of these sound pressure waves can be expressed in sound levels and is used to quantify the effects of such waves in underwater environment.These high underwater noise levels have a large impact on its marine life as marine mammals rely on sound waves, particularly low-frequency wave. The noise from pile driving damages their auditory systems and can lead to multiple injuries making them more vulnerable to predators. For this reason, it is crucial to research methods for predicting underwater noise and reducing the noise during off-shore pile driving operations.The mitigation techniques currently in use or in development lack the ability to filter the sound pressure peaks at a specific frequency band. For this reason, an elastic meta material-based structure, called Meta Cushion, is designed to reduce low-frequency noise during off-shore impact pile driving. To assess the functionality of the Meta Cushion in reducing low-frequency noise during offshore impact pile driving, a small-scale pile driving test setup was designed and built. The small-scale test aimed to validate the numerical results and to provide a better understanding of the cushion's effectiveness. This test was a joint effort of Delft University of Technology and Huisman Equipment B.V..The small-scale impact test setup was scaled using scaling laws on the large-scale appliance, and the instrumentation was selected to perform the required measurements to quantify wave propagation. The test setup was built using a test tank with sound-absorbing foam attached to its walls and soil at the bottom to reduce the reflection waves of the tank sides. In the middle of the tank a small-scaled MP was placed on top of a damping plate, to protect the MP and the bottom of the tank. This damping plate was changed during the experiments, because the initial plate caused a large backlash on the MP after impact. On top of the MP, different cushions were placed, and on the MP wall, a set of strain gauges and an accelerometer was attached to measure the behaviour of the MP throughout the tests. In the tank, a hydrophone was placed to measure the sound pressure as a result of the impact force.The small-scale test setup had three test rounds; the first round assessed the functionality of the meta-material unit cell by testing a modular Meta Cushion made from three different materials: aluminium, acrylic, and nylon, while using a pivot impact hammer; the second and third test rounds were performed on two aluminium non-modular cushions, which were designed and built to withstand the stresses during an impact test with a higher impact force, using a drop weight impact hammer. The FRF-experiments were conducted to extract the actual TL frequency and the attenuation caused by it for each cushion...Mechanical Engineering | Multi-Machine Engineerin
Is sea-basing a viable method of providing logistic support to the UK amphibious force?
No full textMaritime power has traditionally been a central part of the UK’s defence planning and is well
suited to supporting a wide range of military operations. The littoral area has always created
problems for naval planners as most landings historically have had to endure a tactical
separation of the naval and land components, and hence an artificial seam between the Navy
and the Marines. With the end of the Cold War, amphibious operations are going to be more
difficult to conduct than in the past, and amphibious forces are going to have to adopt
manoeuvre warfare capabilities in order to successfully complete their missions. It is very
likely that amphibious forces will have to conduct operations against a numerically superior
enemy, who is on his own terrain, and be surrounded by a neutral, if not hostile populace. As
such, the concept of Operational Manoeuvre From The Sea (OMFTS) whereby the sea is used
as a manoeuvre space, and command and control is fast enough to cope with large amounts of
information, but at the same time allow subordinates maximum flexibility to use their
initiative, is increasingly attractive. It will be important not only for the combat elements to be
able to use this new concept, but the Combat Service Support (CSS) elements as well
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