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This study investigates the variation in available potential energy of stationary eddies in the mid‐troposphere over the midlatitude Northern Hemisphere (30°–60°N) from 1950 to 2021, based on the ERA5 reanalysis and its preliminary back extension. The variation is attributed mainly to changes in the wavenumber‐1 eddy. It is also noted that potential energy conversion from the zonal mean flow in early winter plays an important role in the 20‐year variation. In addition, statistical analysis and numerical simulation of an ICTP model demonstrate that the potential energy conversion is controlled by the North Pacific Gyre Oscillation, which induces anomalous meridional temperature advection in the mid‐troposphere over Northeast Asia. Plain Language Summary: Low‐frequency variation in atmospheric eddies can influence large‐scale and regional climate on a decadal timescale. In addition, the conversion among different forms of energy can be used to diagnose the mechanism leading to the low‐frequency variation of eddies. In this study, we focus on the available potential energy of stationary eddies in the midlatitude Northern Hemisphere. The findings illustrate that available potential energy shows a significant 20‐year variation, which is driven by the North Pacific Gyre Oscillation. Key Points: Available potential energy in the midlatitude Northern Hemisphere demonstrates significant 20‐year variationThe wavenumber‐1 eddy dominates the decadal variation of available potential energy in the midlatitude Northern HemisphereThe North Pacific Gyre Oscillation induces meridional temperature advection, which influences potential energy conversion [ABSTRACT FROM AUTHOR]

Abstract: While separated by large expanses of dry terrain unsuitable for aquatic biota, aridland waters possess high biodiversity. How aquatic micrometazoans disperse to, and colonize, these isolated ephemeral habitats are not well understood. We used a multi‐faceted approach including wind tunnel and rehydration experiments, and next‐generation sequencing to assess potential movement of diapausing propagules of aquatic invertebrates by anemochory across regional scales (102–105 km). Wind tunnel experiments using dry playa sediments with added micrometazoan propagules demonstrated that after entrainment by saltation and downwind transport, propagules could be subsequently rehydrated and were viable. Further, rehydration of fallen natural dust yielded micrometazoans, including rotifers, gastrotrichs, microcrustaceans, and nematodes. Using conserved DNA primers, we identified > 3300 eukaryotic Operational Taxonomic Units (excluding fungi) in the dust including some taxa found in rehydration experiments. Thus, we provide strong evidence that anemochory can disperse micrometazoans among isolated, ephemeral ecosystems in North American deserts and likely elsewhere. [ABSTRACT FROM AUTHOR]

The proportion of elderly persons aged 65 and over in Hong Kong is currently 13.3% and is expected to reach 26.5% by 2031. When experiencing failing health, most elders rely heavily on the indoor facilities available in public housing. However, most public housing is not purposely built for the elderly. To improve elderly quality of life (QoL), appropriate facilities should be provided. Hence, this paper aims to investigate the relationship between the indoor facilities management (FM) of public housing and elderly QoL by a questionnaire survey using the post-occupancy evaluation method. In order to understand the complicated relationships among FM and elderly QoL, reliability analysis, t-test, and correlation analysis were adopted. The results of the ttest and correlation analysis indicated that (1) FM components presented significant differences between old and new public housing; and (2) several FM components, such as distance, lighting, non-slip flooring, and doors, had a significant relationship with final elderly QoL in public housing. Based on the findings, several practical recommendations are proposed, including wide entrances with barrier-free access, the repositioning of power sources to seating or table level and installation of non-slip floors in the bathrooms, and handrails near bath cubicles, toilets, and beds. [ABSTRACT FROM AUTHOR]

A study on low temperature processed solid state dye sensitized solar cell (LT-SDSC) is reported. The LT-SDSC uses a photoelectrode with a mesoporous TiO2 (mp-TiO2) film fabricated from a binder-free nanoparticle-TiO2 paste at room temperature, and a blocking layer of an amorphous TiO2 thin film deposited by atomic layer deposition (ALD) at 150 °C. A power conversion efficiency of 1.30% is obtained from the LT-SDSC with 0.9 μm mp-TiO2 layer and 20 nm ALD-TiO2 blocking layer, in cooperating with organic indoline dyes and a hole conductor, 2,2′,7,7′-Tetrakis-(N,N-di-4-methoxyphenylamino)-9,9′-spirobifluorene (Spiro-OMeTAD). The lower electron conductivity of the low-temperature-processed mp-TiO2 film and the amorphous blocking layer is equilibrated by using smaller thicknesses of the films. Ways to further boost the LT-SDSC performance are proposed. These LT-SDSC are potentially compatible with low cost plastic substrates and show promising manufacturing potential for low cost flexible SDSCs. [ABSTRACT FROM AUTHOR]

A serious difficulty in concurrent programming of a distributed system is how to deal with scheduling and load balancing of such a system which may consist of heterogeneous computers. In this paper, we formulate the static load-balancing problem in single class job distributed systems as a cooperative game among computers. The computers comprising the distributed system are modeled as M/M/1 queueing systems. It is shown that the Nash bargaining solution (NBS) provides an optimal solution (operation point) for the distributed system and it is also a fair solution. We propose a cooperative load-balancing game and present the structure of NBS. For this game an algorithm for computing NBS is derived. We show that the fairness index is always equal to 1 using NBS, which means that the solution is fair to all jobs. Finally, the performance of our cooperative load-balancing scheme is compared with that of other existing schemes. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Due to the increase in the applications of foils, fibres, and yarns under dynamic loading, characterizing the behaviour of small-scaled material samples at high strain rates has become important. However, owing to the low mechanical impedance and the small size of such samples, the conventional split Hopkinson bar technique encounters serious problems, such as high noise-to-signal ratios, an undistinguishable transmitted signal, a short loading time, and difficulty in achieving large strain. A mini-split Hopkinson tensile bar (mini-SHTB) system has been developed to measure the constitutive relation of micro-scaled material specimens under high strain rates. The system employs polymeric bars of small diameter to achieve a closer impedance match with the specimens. This match ensures a lower noise-to-signal ratio in the transmitted signals and hence allows correct interpretation of the transmitted strain profiles. A series of experiments were carried out on different types and forms of material, such as aluminium foil, cellulose nitrate foil, badminton racket string, and so forth, to verify the applicability of the apparatus. Strain rates in the order of 102 were attained under this mini-SHTB system. The results confirm that the tensile stress–strain behaviour of small-sized specimens, with low mechanical impedance and under high strain rates, can be determined effectively and efficiently using this technique. [ABSTRACT FROM AUTHOR]

Fibers/fabrics coated with conductive polymers exhibit sensing capacities for external stimuli like strain, temperature, relative humidity, etc. In this paper, we present our recent investigation of the sensing behavior and mechanical analysis of polymer fibers coated with an intrinsically conductive polymer, i.e., polypyrrole (PPy). PPy-coated PA6 fibers and PPy-coated Lycra fibers are prepared by chemical vapor deposition using pyrrole in the presence of an oxidizing agent, and their electromechanical behavior under tensile load is studied experimentally. The mechanism governing the electromechanical behavior of these conductive fibers is investigated, and the effects of various factors that are responsible for variations in the electrical resistance are discussed. An electromechanical model is proposed that correlates the resistance change with the applied strain, the damage level of the conductive fibers, the environmental temperature, and the relative humidity. The model provides a theoretical basis for the analysis and design of electrically conductive fabrics. [ABSTRACT FROM AUTHOR]

The relationship between construction output and economic growth has been well discussed by construction economists. Most of the previous studies found a positive correlation between gross domestic product (GDP) per capita and various measures of construction output. However, cross-sectional analysis was commonly adopted but longitudinal analysis has been called upon. Furthermore, recent research argued that non-linear relationship between GDP and construction output exists because of different stages of economic development in different countries. They explained the phenomenon by means of the change of the growth rates of construction output at different stages of economic development, but the argument has not yet been rigorously tested. With the availability of long time-series of data of Hong Kong construction industry, this paper attempts to test longitudinally the relationship between the real growth rate of construction output and the real growth rate of GDP. It was found that the growth rate of GDP led that of construction output, and as the growth rate of GDP increased, the growth rate of construction output was marginally diminishing. It agrees with the proposition that construction industry is relatively inefficient in productivity improvement and the accumulation of capital investment results in a marginally diminishing growth of construction output. [ABSTRACT FROM AUTHOR]