wear and tear
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PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0261891
Author(s):  
David G. Blanchflower ◽  
Alex Bryson

A recent paper showed that, whereas we expect pain to rise with age due to accumulated injury, physical wear and tear, and disease, the elderly in America report less pain than those in midlife. Further exploration revealed this pattern was confined to the less educated. The authors called this the ‘mystery of American pain’ since pain appears to rise with age in other countries irrespective of education. Revisiting this issue with the same cross-sectional data we show that what matters in explaining pain through to age 65 is whether one is working or not. The incidence of pain across the life-course is nearly identical for workers in America and elsewhere, but it is greater for non-working Americans than it is for non-workers elsewhere. As in other countries, pain is hump-shaped in age among those Americans out of work but rises a little over the life-course for those in work. Furthermore, these patterns are apparent within educational groups. We show that, if one ascribes age-specific employment rates from other OECD countries to Americans, the age profile of pain in the United States is more similar to that found elsewhere in the OECD. This is because employment rates are lower in the United States than elsewhere between ages 30 and 60: the simulation reduces the pain contribution of these non-workers to overall pain in America, so it looks somewhat similar to pain elsewhere. We conclude that what matters in explaining pain over the life-course is whether one is working or not and once that is accounted for, the patterns are consistent across the United States and the rest of the OECD.


Technologies ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 7
Author(s):  
Christos Sevastopoulos ◽  
Stasinos Konstantopoulos ◽  
Keshav Balaji ◽  
Mohammad Zaki Zadeh ◽  
Fillia Makedon

Training on simulation data has proven invaluable in applying machine learning in robotics. However, when looking at robot vision in particular, simulated images cannot be directly used no matter how realistic the image rendering is, as many physical parameters (temperature, humidity, wear-and-tear in time) vary and affect texture and lighting in ways that cannot be encoded in the simulation. In this article we propose a different approach for extracting value from simulated environments: although neither of the trained models can be used nor are any evaluation scores expected to be the same on simulated and physical data, the conclusions drawn from simulated experiments might be valid. If this is the case, then simulated environments can be used in early-stage experimentation with different network architectures and features. This will expedite the early development phase before moving to (harder to conduct) physical experiments in order to evaluate the most promising approaches. In order to test this idea we created two simulated environments for the Unity engine, acquired simulated visual datasets, and used them to reproduce experiments originally carried out in a physical environment. The comparison of the conclusions drawn in the physical and the simulated experiments is promising regarding the validity of our approach.


2022 ◽  
Vol 16 (4) ◽  
pp. 102-108
Author(s):  
I. N. Novoseletskii ◽  
S. V. Fedotov

The article is devoted to the problem of the validity of determining the wear of component parts when calculating the damage caused to a vehicle due to its deterioration. The authors address the legal line of arguments of the differentiated approach when deciding on the need to consider wear and tear. They also make suggestions on its practical reflection in forensic expert opinions. Finally, it is highlighted that when making decisions regarding wear and tear, it is essential to consider the method of compensation for damage caused and official legal information.The authors justify the necessity to use the provisions of the methodological recommendations developed in the Federal State Budgetary Institution of the Russian Federation under the Ministry of Justice of the Russian Federation in the calculations, which will allow experts to formulate categorical and not relative or multivariate conclusions.


Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 87
Author(s):  
Turki M. Habeebullah ◽  
Said Munir ◽  
Jahan Zeb ◽  
Essam A. Morsy

In this paper, atmospheric water-soluble cation and anion contents of PM10 are analysed in Makkah, Saudi Arabia. PM10 samples were collected at five sites for a whole year. PM10 concentrations (µg/m3) ranged from 82.11 to 739.61 at Aziziyah, 65.37 to 421.71 at Sanaiyah, 25.20 to 466.60 at Misfalah, 52.56 to 507.23 at Abdeyah, and 40.91 to 471.99 at Askan. Both daily and annual averaged PM10 concentrations exceeded WHO and Saudi Arabia national air quality limits. Daily averaged PM10 concentration exceeded the national air quality limits of 340 µg/m3, 32% of the time at Aziziyah, 8% of the time at Sanaiyah, and 6% of the time at the other three sites. On average, the cations and anions made a 37.81% contribution to the PM10 concentrations. SO42−, NO3−, Ca2+, Na+, and Cl− contributed 50.25%, 16.43%, 12.11%, 11.12%, and 8.70% to the total ion concentrations, respectively. The minor ions (F−, Br−, Mg2+, NO2−, and PO43−) contributed just over 1% to the ion mass. Four principal components explained 89% variations in PM10 concentrations. Four major emission sources were identified: (a) Road traffic, including emission from the exhaust, wear-and-tear, and the resuspension of dust particles (F−, SO42−, NO3−, Ca2+, Na+, Mg+, Br−, Cl−, NO2−, PO43−); (b) Mineral dust (Cl−, F−, Na+, Ca2+, Mg2+, PO43−); (c) Industries and construction–demolition work (F−, SO42−, Ca2+, Mg2+); and (d) Seaspray and marine aerosols (Cl−, Br−, Mg2+, Na+). Future work would include an analysis of the metal contents of PM10 and their spatiotemporal variability in Makkah.


2022 ◽  
Author(s):  
Anthony Ong ◽  
Betul Urganci ◽  
Anthony L. Burrow ◽  
Tracy DeHart

The wear and tear of adapting to chronic stressors such as racism and discrimination can have detrimental effects on mental and physical health. Here, we investigate the wider implications of everyday racism for relationship quality in a sample of 98 heterosexual African American couples. Participants reported on their experiences of racial discrimination and positive and negative affect for 21 consecutive evenings. Using dyadic analyses, we show that independent of age, gender, marital status, income, racial discrimination frequency, neuroticism, and mean levels of affect, participants’ relationship quality was inversely associated with their partner’s negative affective reactivity to racial discrimination. Associations did not vary by gender, suggesting that the effects of affective reactivity were similar for men and women. These findings highlight the importance of a dyadic approach and call for further research examining the role of everyday racism as a key source of stress in the lives of African American couples.


2021 ◽  
Vol 12 (1) ◽  
pp. 30
Author(s):  
Waseem Amjad ◽  
Adil Nawaz ◽  
Anjum Munir ◽  
Faisal Mahmood

The heat extraction from and cooling of computer microprocessors are challenging tasks in the modern era. Previously, the microprocessors were usually cooled by air, but now industry is shifting towards using nanofluids, as their properties are more thermo-physically stable. The experimental and numerical studies have revealed that the rate of heat transfer depends both on the thermal characteristics of the coolant and the geometry of the heat sink. For optimized results, it is recommended to analyze the combined effect of nanofluids and the geometry of the heat sink. Mini-channel heat sinks in combination with a nanofluid offered an excellent rate of heat transfer. However, passing nanofluids continuously through the system causes various problems over time; for example, the thermal stresses on the components are increased, which may lead to wear and tear of the system. In this study, a numerical investigation of mini-channel heat sinks was conducted through thermal-FSI. A numerical model was established with airfoil and Savonius pin-fin mini channel heat sinks, and they were analyzed at different flow rates from 0.25 LPM to 0.75 LPM with an increment of 0.25 LPM with different fluids, i.e., water, Al2O3–H2O, and Fe2O3–H2O nanofluids, varying their volumetric concentration. The minimum stresses were obtained while increasing the temperature drop and decreasing the pressure drop. The thermal stresses were calculated using the thermal-FSI technique and were found to be in the threshold range, and hence the material was within the yield limit at 0.75 LPM when using the Fe2O3-H2O Nanofluid at a 0° angle using the Savonius heat sink.


2021 ◽  
Author(s):  
Mananathan R

With over thirty years of experience in the design, development, and patenting of some products in the field of wheel alignment, the author shares his knowledge on the importance of wheel maintenance to the overall performance of a vehicle. From the ancient bullock carts to chariots to automobiles, wheels have undergone many changes to serve the purpose of mankind's mobility. Mobility is inevitable in today's life. A world without wheels is unimaginable. Every vehicle owner expects his tires to last longer and perform better. But improper wheel alignment and wheel balancing can drastically impact the wear and tear on a tire. This book walks the readers through the basics to techniques for wheel alignment on light vehicles, commercial vehicles, and trailers. In addition, illustrations present various types of tire wear and the cause of each. Finally, the author delves into tire safety from understanding how air pressure effects a tire to the importance of tire rotation.


2021 ◽  
Vol 8 ◽  
pp. 41-49
Author(s):  
Dongdong Song ◽  
Yingxin Yang ◽  
Haitao Ren

PDC (Polycrystalline Diamond Compact bit) composite is the most important cutting element of petroleum bit, which performance directly affects the service effect and service life of the bit. During the drilling process, the cutter will produce a large amount of friction heat when cutting the rock, resulting in a sharp increase in the internal temperature of the cutter. When the temperature reaches a certain value, thermal wear and tear are very easy to occur, which will not only cause diamond delamination but also reduce the wear resistance of the cutter. Under the action of impact load, impact failure is more likely to occur, which greatly reduces the service life of the cutter and the rock-breaking efficiency of the drill bit. Therefore, this paper studies the composite interface suitable for high-temperature drilling through the changes of cutting tooth temperature field and stress field with different interface shapes, which shows that the non-planar interface is more suitable for improving the cutting tooth life of composite under the action of comprehensive stress field.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Venkatesa Prabhu Sundramurthy ◽  
Thirumullaivoyal G. Nithya ◽  
Chandran Masi ◽  
Chinnasamy Gomadurai ◽  
Ebrahim M. Abda

Abstract Any material when utilized for a required period of time and segment, the leftover residues of those materials are known as waste. Enormous waste is generated during such wear and tear process of materials depending on the usage and functions in a routine lifestyle. Those generated waste when overloaded beyond the capacity of natural recycling processes, would influence the environment and human health. Hence, the waste generated from used materials should be managed according to the environmental impact. Even though wastes are also sometimes rich in organic compounds, nutrients, and energy resources, they are not experimented and managed appropriately. Recently, different feasible techniques are invented and followed to recover and reuse the efficient resources that can create and support sustainable livelihood by creating green economy effects by reducing waste. In this chapter, the emphasis has been given to providing an overview of recent advancements on bio-based waste management and product recoveries such as microbes mediated approaches, biorefineries for waste valorization, and bioenergy from industrial waste.


2021 ◽  
Author(s):  
◽  
Lakjith Manapaya Weeratunge

<p>Physical moving parts are prone to wear and tear. A pixel display can manifest complex motion and realistic images in full colour offering a form of tangibly while being less likely to suffer from wear and tear however, it remains restricted to 2D surfaces. The recent development in voxel-based printing (voxel = 3D pixel) allows multi-material and multi-colour 3D printing to transform images into physical objects. However, during the printing process the capacity to change the pixels colour and position in the future are lost, effectively fusing the digital information. The high demand for immersive experiences in video games, films, museums and interactive products are omnipresent. The combination of pixel display technology and multi-material 3D printing is a potential avenue to create immersive experiences to feed this high demand.</p>


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