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The purpose of this paper is to show that the droplet impact phenomenon is important for the advancement of industrial technologies in many fields such as spray cooling and ink jet printing. Droplet bouncing on the nonwetting surfaces is a special phenomenon in the impact process which has attracted lots of attention.

In this work, the authors fabricated two kinds of representative nonwetting surfaces including superhydrophobic surfaces (SHS) and a slippery liquid-infused porous surface (SLIPS) with advanced UV laser processing.

The droplet bouncing behavior on the two kinds of nonwetting surfaces were compared in the experiments. The results indicate that the increasing Weber number enlarges the maximum droplet spreading diameter and raises the droplet bounce height but has no effect on contact time.

In addition, the authors find that the topological SHS and SLIPS with the laser-processed microwedge groove array produce asymmetric droplet bouncing with opposite offset direction. Microdroplets can be continuously transported without any additional driving force on such a topological SLIPS. The promising method for manipulating droplets has potential applications for the droplet-based microfluidic platforms.

Since construction workers often need to carry various types of loads in their daily routine, they are at risk of sustaining musculoskeletal injuries. Additionally, carrying a load during walking may disturb their walking balance and lead to fall injuries among construction workers. Different load carrying techniques may also cause different extents of physical exertion. Therefore, the purpose of this paper is to examine the effects of different load-carrying techniques on gait parameters, dynamic balance, and physiological parameters in asymptomatic individuals on both stable and unstable surfaces.

Fifteen asymptomatic male participants (mean age: 31.5 ± 2.6 years) walked along an 8-m walkway on flat and foam surfaces with and without a load thrice using three different techniques (e.g. load carriage on the head, on the dominant shoulder, and in both hands). Temporal gait parameters (e.g. gait speed, cadence, and double support time), gait symmetry (e.g. step time, stance time, and swing time symmetry), and dynamic balance parameters [e.g. anteroposterior and mediolateral center of pressure (CoP) displacement, and CoP velocity] were evaluated. Additionally, the heart rate (HR) and electrodermal activity (EDA) was assessed to estimate physiological parameters.

The gait speed was significantly higher when the load was carried in both hands compared to other techniques (Hand load, 1.02 ms vs Head load, 0.82 ms vs Shoulder load, 0.78 ms). Stride frequency was significantly decreased during load carrying on the head than the load in both hands (46.5 vs 51.7 strides/m). Step, stance, and swing time symmetry were significantly poorer during load carrying on the shoulder than the load in both hands (Step time symmetry ration, 1.10 vs 1.04; Stance time symmetry ratio, 1.11 vs 1.05; Swing time symmetry ratio, 1.11 vs 1.04). The anteroposterior (Shoulder load, 17.47 mm vs Head load, 21.10 mm vs Hand load, −5.10 mm) and mediolateral CoP displacements (Shoulder load, −0.57 mm vs Head load, −1.53 mm vs Hand load, −3.37 ms) significantly increased during load carrying on the shoulder or head compared to a load in both hands. The HR (Head load, 85.2 beats/m vs Shoulder load, 77.5 beats/m vs No load, 69.5 beats/m) and EDA (Hand load, 14.0 µS vs Head load, 14.3 µS vs Shoulder load, 14.1 µS vs No load, 9.0 µS) were significantly larger during load carrying than no load.

The findings suggest that carrying loads in both hands yields better gait symmetry and dynamic balance than carrying loads on the dominant shoulder or head. Construction managers/instructors should recommend construction workers to carry loads in both hands to improve their gait symmetry and dynamic balance and to lower their risk of falls.

The potential changes in gait and balance parameters during various load carrying methods will aid the assessment of fall risk in construction workers during loaded walking. Wearable insole sensors that monitor gait and balance in real-time would enable safety managers to identify workers who are at risk of falling during load carriage due to various reasons (e.g. physical exertion, improper carrying techniques, fatigue). Such technology can also empower them to take the necessary steps to prevent falls.

This is the first study to use wearable insole sensors and a photoplethysmography device to assess the impacts of various load carrying approaches on gait parameters, dynamic balance, and physiological measures (i.e. HR and EDA) while walking on stable and unstable terrains.

The texturalcentric model of non‐attribute‐based visual and tactile response to textural fabric surfaces was used to elicit definitive qualities or dimensions of textural fabric surfaces. Multidimensional scaling analysis permitted subjects to provide numeric judgements of fabrics rather than using words with individuals' historic definitions of those terms, or without understanding some terms. Objectives of the study included validating the attributes identified by college students, and ascertaining the persistence of attributes that contribute to visual and tactile perception of adult women (25–45 years of age) and older women (60 years of age and older). One‐hundred‐and‐twenty subjects (50 per cent adult, 50 per cent older) provided visual or tactile ratings of the similarities of 30 fabrics. Data were subjected to multidimensional scaling analysis and coefficients of congruence were calculated. Dimensions or characteristics of fabrics were named using bipolar adjectives: rough to smooth, plane to depth, irregular to regular surface units, shiny to matt, fine to coarse, lightweight to heavyweight, simple to complex, hard to soft compressibility, pliable to stiff, harsh to slippery, small units to large units, open to compact, and soft to bumpy‐rough. From these, a schema for the textural perception of fabric surfaces, was modelled.

Muslims require an exclusive ablution space for preparing for daily prayers in mosques. Ablution floors seem to entail design challenges since they are often encountered in lubricated conditions from worshippers’ body cleaning manoeuvers. Accordingly, fall risks on saturated surfaces of ablution floors would be a major issue to Muslim worshippers. Thus, the purpose of this study is to investigate the safety status of mosque ablution floors in terms of slip resistance properties and surface texture.

Fifteen mosques in Dubai and Sharjah cities of the UAE were randomly chosen to investigate the safety conditions of ablution spaces. In-situ slip-resistance properties and surface finishes of each ablution floor were measured under clean, wet, and soapy conditions at two different volumes of traffic areas: heavy- and non-traffic. Surface finishes of ablution floors were also measured and analysed.

Outcomes from this study evidently showed that the inspected ablution floors were not currently protected against falls, especially under wet and soapy environments. Surface analyses identified that the present ablution floors have extremely flat surfaces (? 2 µm in the Ra parameter) so they require significant improvements against fall risks.

Regardless of the magnitude of this issue, it is scarce to attain any published study on ablution floors’ fall incidence and avoidance plans in the scientific and technical literature. There are also no officially and publicly available data on fall incidents from ablution places in mosques. Findings from this study would be a great step forward to establish safer ablution floors for Muslim prayers.

Fabrics’ thermal properties greatly influence human comfort during wear. For this reason, fabrics with optimum thermal properties need to be developed. This paper aims to investigate the effect of weft yarn twist levels on thermal and surface properties of 100 per cent cotton woven fabrics.

Five types of plain woven cotton fabrics were manufactured using weft yarns with 900, 905, 910, 915 and 920 twists/meter (Tpm). The other parameters of the samples as count, thread density and fabric structures were kept constant. Fabric thermal properties were evaluated by measuring its thermal conductivity, thermal resistance, actual insulation, water permeability, air permeability and wicking ability. The fabric compression and surface properties were also evaluated because they contribute to the overall clothing comfort.

The results showed that actual insulation and thermal resistance property decreased with an increase in twists/meter of the weft yarn. However, thermal conductivity does not significantly change while fabric compression reduced with an increase in twist as the surface roughness increased.

Comfort is a fundamental requirement in human daily existence, and it is greatly influenced by clothing, which comes in close contact with the human skin. Fabrics’ thermal properties greatly influence human comfort during wear. For this reason, fabrics with optimum thermal properties need to be developed.

The purpose of this paper is to present a new low‐cost system based on a spherical robot for performing moisture monitoring in precision agriculture.

The work arose from the necessity of providing farmers with alternative methods for crop monitoring. Thus, after analysing the main requirements, a spherical robot was chosen as a tentative approach. The presented work summarizes the work carried out in selecting the basics to apply in the robot, as well as its mechanical and electronic design. After designing and constructing the robot, several tests have been performed, in order to validate the robot for performing monitoring task and moving on different types of soil.

The performed tests reveal that spherical robot is a suitable solution for performing the task.

Some improvements in control should be applied in order to reach a fully autonomous navigation in very slippery soils. Nevertheless, the performance of the robot in teleoperated mode allows validating of the system.

The robot turned out to be friendly and harmless in its use for this application. The cost of final series will be affordable in comparison with the cost of other methods. Endurance of the robot can be considered as fair.

The paper presents a new tool for farming based on non‐common robot.

Aims to describe the application of robotics to the cleaning of the glass roof of the 21 m high pyramid that stands in front of the Louvre in Paris.

Presents the design of the robot, its traction mechanism, cleaning system and operating mode.

Finds that a robot is capable of cleaning a glass roof at a great height and on a steep slope using only suction to adhere to the surface.

Introduces the concept of a robot in commercial use that cleans a steeply sloping glass roof.