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In this study, we aimed to demonstrate the importance of diabatic heating in extreme rainstorm weather events induced by the Southwest China vortex (SWCV) in different precipitation regions with a similar circulation background. The results showed that atmospheric diabatic heating had indicative significance for the intensity evolution of the SWCV and the precipitation area. Changes in the diabatic heating intensity preceded the intensity evolution of the SWCV, and the diabatic heating region was consistent with the heavy precipitation region. The variation in diabatic heating was mainly due to the positive contribution of its vertical transport term. The two types of spatially non-uniform heating effects were similar; however, the western type was located southeast of the SWCV, with an asymmetric distribution on the southeastern and northwestern sides. The eastern type was located in the northeast of the SWCV, with an asymmetric distribution on the northeastern and southwestern sides. The vertically non-uniform heating effect played a decisive role in the distribution and evolution of the spatially non-uniform heating terms. The vertically non-uniform heating effect affected the intensity evolution of the SWCV. In contrast, the horizontally non-uniform heating effect, in opposition to the vertically non-uniform heating effect, had a slightly weaker intensity than the vertically non-uniform heating effect. For the SWCV system, which induces extreme rainstorms, the magnitude of the horizontally non-uniform heating effect could reach that of vertically non-uniform heating; thus, the possible impact of horizontally non-uniform heating should be considered.

In this study, design considerations of a new device structure are presented to improve the self‐heating effect (SHE) and the breakdown voltage of the Deep Gate LDMOS (Lateral Double Diffused Metal Oxide Semiconductor) transistor and compared with a conventional LDMOS (C‐LDMOS). In this case, triple oxide trenches with an N+ trench are embedded in the drift region. These trenches create additional peaks in the electric field profile, so the electric field is modified. The authors demonstrate that by optimising the trenches, the breakdown voltage of the device increases. Also, a partially buried oxide is used in the proposed structure to create a conduction path that significantly reduces the SHE. Moreover, the results indicate that the specific on‐resistance, lattice temperature, and breakdown voltage of the proposed device are improved considerably compared to the C‐LDMOS.

The self-heating effect can be considered as a catastrophic phenomenon that occurs in polymers and polymer–matrix composites (PMCs) subjected to fatigue loading or vibrations. This phenomenon appears in the form of temperature growth in such structures due to their relatively low thermal conductivities. The appearance of thermal stress resulting from temperature growth and the coefficient of thermal expansion (CTE) mismatch between fibers and neighboring polymer matrix initiates and/or accelerates structural degradation and consequently provokes sudden fatigue failure in the structures. Therefore, it is of primary significance for a number of practical applications to first characterize the degradation mechanism at the nano-, micro- and macroscales caused by the self-heating phenomenon and then minimize it through the implementation of numerous approaches. One viable solution is to cool the surfaces of considered structures using various cooling scenarios, such as environmental and operational factors, linked with convection, contributing to enhancing heat removal through convection. Furthermore, if materials are appropriately selected regarding their thermomechanical properties involving thermal conductivity, structural degradation may be prevented or at least minimized. This article presents a benchmarking survey of the conducted research studies associated with the fatigue performance of cyclically loaded PMC structures and an analysis of possible solutions to avoid structural degradation caused by the self-heating effect.

Introduction While many epidemiological studies have shown that low outdoor temperatures are associated with increased rates of hospitalisation and mortality (especially for respiratory or cardiovascular disease), very few studies have looked at the association between indoor temperatures and health. Such studies are clearly warranted, as people have greater exposure to the indoor environment than the outdoor environment. Objectives To examine the relationship between various metrics of indoor temperature and lung function in children with asthma. Our specific research questions were: (1) In which room of the home is temperature most strongly associated with lung function? (2) Which exposure metric best describes the relationship between indoor temperature and lung function? (3) Over what lag/time period does indoor air temperature affect lung function most strongly? Methods The Heating Housing and Health Study was a randomised controlled trial that investigated the effect of installing heaters in the homes of children with asthma. This study collected measurements of lung function (daily) and indoor temperature (hourly). Lung function and indoor temperature were measured for 309 children over 12 049 child-days. Statistical models were fitted to identify the best measures and metrics. Results The strongest association with lung function was found for the severity of exposure to low bedroom temperatures averaged over the preceding periods of 0–7 to 0–12 days. A 1°C increase in temperature was associated with an average increase of 0.010, 0.008, 10.06, 12.06, in our four measures of lung function (peak expiratory flow rate (PEFR) morning, PEFR evening, forced expiratory volume in 1 s (FEV1) morning and FEV1 evening). Conclusions Indoor temperatures have a small, but significant, association with short-term variations in the lung function of children with asthma.

The self-heating effect is a dangerous phenomenon that occurs in polymers and polymer matrix composites during their cyclic loading, and may significantly influence structural degradation and durability as a consequence. Therefore, an analysis of its criticality is highly demanding, due to the wide occurrence of this effect, both in laboratory fatigue tests, as well as in engineering practice. In order to overcome the problem of the accelerated degradation of polymer matrix structures, it is essential to evaluate the characteristic temperature values of self-heating, which are critical from the point of view of the fatigue life of these structures, i.e., the temperature at which damage initiates, and the safe temperature range in which these structures can be safely maintained. The experimental studies performed were focused on the determination of the critical self-heating temperature, using various approaches and measurement techniques. This paper present an overview of the research studies performed in the field of structural degradation, due to self-heating, and summarizes the studies performed on the evaluation of the criticality of the self-heating effect. Moreover, the non-destructive testing method, which uses the self-heating effect as a thermal excitation source, is discussed, and the non-destructivity of this method is confirmed by experimental results.

Dynamical downscaling generally performs poorly on the Tibetan Plateau (TP), due to the region’s complex topography and several aspects of model physics, especially convection and land surface processes. This study investigated the effects of the cumulus parameterization scheme (CPS) and land-surface hydrology scheme (LSHS) on TP climate simulation during the wet season using the RegCM4 regional climate model. To address these issues and seek an optimal simulation, we conducted four experiments at a 20 km resolution using various combinations of two CPSs (Grell and MIT-Emanuel), two LSHSs (the default TOPMODEL [TOP], and Variable Infiltration Capacity [VIC]). The simulations in terms of 2-m air temperature, precipitation (including large-scale precipitation [LSP] and convective precipitation [CP]), surface energy-water balance, as well as atmospheric moisture flux transport and vertical motion were compared with surface and satellite-based observations as well as the ERA5 reanalysis dataset for the period 2006–2016. The results revealed that the model using the Grell and TOP schemes better reproduced air temperature but with a warm bias, part of which could be significantly decreased by the MIT scheme. All schemes simulated a reasonable spatial distribution of precipitation, with the best performance in the experiment using the MIT and VIC schemes. Excessive precipitation was produced by the Grell scheme, mainly due to overestimated LSP, while the MIT scheme largely reduced the overestimation, and the simulated contribution of CP to total precipitation was in close agreement with the ERA5 data. The RegCM4 model satisfactorily captured diurnal cycles of precipitation amount and frequency, although there remained some differences in phase and magnitude, which were mainly caused by the CPSs. Relative to the Grell scheme, the MIT scheme yielded a weaker surface heating by reducing net radiation fluxes and the Bowen ratio. Consequently, anomalous moisture flux transport was substantially reduced over the southeastern TP, leading to a decrease in precipitation. The VIC scheme could also help decrease the wet bias by reducing surface heating. Further analysis indicated that the high CP in the MIT simulations could be attributed to destabilization in the low and mid-troposphere, while the VIC scheme tended to inhibit shallow convection, thereby decreasing CP. This study’s results also suggest that CPS interacts with LSHS to affect the simulated climate over the TP.

Purpose Despite the rapid development of fused deposition modeling (FDM), the insufficient mechanical strength of the printed objects is one of the biggest stumbling blocks for practical applications. Therefore, the purpose of this study is to emphasize on the importance of homogeneous heating condition and heating effect in the improvement of the mechanical strength of objects. Design/methodology/approach The authors first analyze the problem of the present heating system under a heating bed and chamber by using a commonly used home FDM printer. Next, they investigate the heating effect on the mechanical properties of FDM-printed objects in terms of layer thickness, heating duration and additional pressure with heating. The printed objects are treated in a mold by forced convection heating. Findings As the layer thickness decreases, the mechanical performance of the FDM-printed objects is remarkably enhanced by thermal heating because of the result of strong interfacial bonding among the rasters and layers. In addition, longer heating duration and higher external pressure play pivotal roles in the mechanical performance by reducing voids in the internal structure of the printed objects, leading to high densification and complete filling at the interfaces. Originality/value The present findings, for the first time, show that controlling uniform heat transfer is highly important for the mechanical performance of FDM three-dimensional printed objects. The authors suggest that the future developed home or personal FDM types should consider the homogeneous temperature environment during the printing process by properly heating the inside chamber. In addition, the results indicate the effectiveness of heating and pressure treatment to the objects for the reinforced mechanical performance and better surface finish.

Background Approximately 70,000 to 75,000 proximal femoral fracture repairs take place in the UK each year. Hemiarthroplasty is the preferred treatment for adults aged over 60 years. Postoperative infection affects up to 3% of patients and is the single most common reason for early return to theatre. Ultraclean ventilation was introduced to help mitigate the risk of infection, but it may also contribute to inadvertent perioperative hypothermia, which itself is a risk for postoperative infection. To counter this, active intraoperative warming is used for all procedures that take 30 min or more. Forced air warming (FAW) and resistive fabric warming (RFW) are the two principal techniques used for this purpose; they are equally effective in prevention of inadvertent perioperative hypothermia, but it is not known which is associated with the lowest infection rates. Deep surgical site infection doubles operative costs, triples investigation costs and quadruples ward costs. The Reducing Implant Infection in Orthopaedics (RIIiO) study seeks to compare infection rates with FAW versus RFW after hemiarthroplasty for hip fracture. A cost-neutral intervention capable of reducing postoperative infection rates would likely lead to a change in practice, yield significant savings for the health economy, reduce overall exposure to antibiotics and improve outcomes following hip fracture in the elderly. The findings may be transferable to other orthopaedic implant procedures and to non-orthopaedic surgical specialties. Methods RIIiO is a parallel group, open label study randomising hip fracture patients over 60 years of age who are undergoing hemiarthroplasty to RFW or FAW. Participants are followed up for 3 months. Definitive deep surgical site infection within 90 days of surgery, the primary endpoint, is determined by a blinded endpoint committee. Discussion Hemiarthroplasty carries a risk of deep surgical site infection of approximately 3%. In order to provide 90% power to demonstrate an absolute risk reduction of 1%, using a 5% significance level, a full trial would need to recruit approximately 8630 participants. A pilot study is being conducted in the first instance to demonstrate that recruitment and data management strategies are appropriate and robust before embarking on a large multi-centre trial. Trial registration ISRCTN, ISRCTN74612906 . Registered on 27 February 2017.

The gate-all-around (GAA) nanosheet (NS) field-effect-transistor (FET) is poised to replace FinFET in the 3 nm CMOS technology node and beyond, marking the second seminal shift in device architecture across the extensive 60-plus-year history of MOSFET. The introduction of a new device structure, coupled with aggressive pitch scaling, can give rise to reliability challenges. In this article, we present a review of the key reliability mechanisms in GAA NS FET, including bias temperature instability (BTI), hot carrier injection (HCI), gate oxide (Gox) time-dependent dielectric breakdown (TDDB), and middle-of-line (MOL) TDDB. We aim to not only underscore the unique reliability attributes inherent to NS architecture but also provide a holistic view of the status and prospects of NS reliability, taking into account the challenges posed by future scaling.

Metal nanoparticle@porous material composites have attracted increasing attention due to their excellent synergistic catalytic performance. However, it is a challenge to introduce metal nanoparticles into cavities of porous materials without agglomeration on the exterior. Despite the progress achieved, a universal approach that can integrate different kinds of metal nanoparticles and porous materials is still highly desirable. Here we report a facile and general approach to fabricating metal nanoparticle@porous materials by microwave-triggered selective heating. The microwave can pass through the non-polar solvent and act on the polar solvent in the porous materials, causing the polar solvent to be heated, vaporized, and away from the pores of porous materials. The local void produced by the escape of polar solvent facilitates non-polar solvent containing metallic precursor to be dragged into the narrow pores, followed by further reduction, resulting in the complete encapsulation of nanoparticles. A series of metal nanoparticles@porous materials, ranging from metal-organic frameworks (MOFs) to zeolites, are successfully prepared by this method and show excellent size selectivity in catalytic reactions.