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Clothing is subject to a dynamic thermal transport process in its routine service in which the apparel and human body together with environment interact with each other. Understanding of the thermal transfer in this case should take the variations of human body and environment together with clothing attributes into consideration. The paper aims to discuss these issues.

Based on the purpose-built dynamic thermal and moisture tester, this study focuses on the thermal transfer of fabrics in different rotational motions. The energy consumption and power of the simulated human skin, the temperature and the thermal retention rate were monitored in the process of rotation of the testing platform with gradually increased rotating speed.

It has been found that the thermal transfer of a rotating fabric is greatly affected by the rotating speed, the angle of the fabric toward the moving direction and the attributes of the fabric such as its thickness, layers, structure and its fiber composition.

This study will benefit the understanding of the dynamic thermal interaction of human with the environment, and the designing of clothing with excellent thermal comfort.

This work reveals the dynamic thermal transfer of fabrics in rotational motions. It provides a platform to study the dynamic thermal behavior of clothing in daily use.

Fibers based regenerated protein draw much attention for recycling discarded protein resources and can produce biodegradable and environmental friendly polymers. In this study, superfine wool powder is blended with polypropylene (PP) to produce wool powder/PP blend film through extrusion and hot-pressing. Hydrogen peroxide is used to bleach the black colored surface of the blend films. The effects of peroxide concentration, bleaching time and powder content on the final whiteness and mechanical properties of the blend films are investigated.

The bleached films are dyed with acid red dyes and the dyed color is evaluated using a Computer Color Matching System. Color characters of dyed films, such as L^*, a^*, b*, ΔE^*ab, C^*ab and K/S values are measured and analyzed. The study not only reuses discarded wool resources into organic powder, widens the application of superfine wool powder on polymers, but also improves the dyeing properties of PP through the addition of protein content.

In this paper, silk powder around 1.5 micrometer average in size was developed and its dyeing property was compared with normal silk fiber. The results show that silk powder has a very high dye uptake property and can be dyed at room temperature; it can also be used to improve the dyeing property of some materials when it acts as a kind of additive agent. The K/S value of silk fiber is higher than that of silk powder. Their K/S value of silk fiber and silk superfine powder are influenced largely by the dye concentration. The WXRD diffraction curves showed that the crystallinity of silk powder is lower than that of silk fiber. FTIR spectra of silk powder showed that the intensity peak of CH₂-antisymmetrical stretching vibration largely decreased, and the peak of C=O symmetrical stretching vibration of amid bond moved to the high wave-number. TG patterns of samples showed that water (moisture) could be easily removed from the powder when the temperature was over 70°C, and the initial decomposition temperature of silk powder increased from 262.5°C to 277.5°C. Moreover, the silk powder showed higher residue than that of silk fiber at 600°C.

The purpose of this paper is to present a dynamic analysis on the thermal and electrical properties of fabrics under wet conditions.

A purpose‐built apparatus is applied to test the thermal and electrical properties of textiles in moisture absorption and liberation process. Relation between temperature and resistance of a cotton/polyester double‐layer fabric is also analysed.

The surface temperature of textiles shows three different stages in the process. The electrical resistance is linearly related to the reciprocal of the moisture regain of fabrics. In the moisture absorption and liberation process, surface temperature of cotton layer is higher than that of polyester layer. And the electrical resistance of cotton layer decreases more quickly than that of polyester layer. The electrical resistance changes earlier than surface temperature in the moisture‐liberation process.

The paper is helpful in not only the designing of sportswear, but also the devising of moisture‐testing apparatus.

A dynamic testing method is applied to characterize the thermal and electrical properties of textiles.

In this study, a novel dynamic testing method was established to measure the moisture variation of fabric surface during the process of moisture liberation in simulated windy condition. The paper aims to discuss these issues

In this method, the samples were rotating during the test process so as to simulate the external windy environment. Effects of simulated wind speed, moisture regains and fabric materials on the surface moisture of fabric were investigated.

Experimental results showed that the surface moisture presented a trapezoidal moisture liberation curve, it increased at first, then kept stable for a while, and decreased finally with the increase of time. It took longer time for the fabric to complete the liberation process when the moisture regain of the fabric increased or the simulated wind speed decreased. The fiber materials of the fabric affected the time for the moisture liberation process under a specific windy condition.

This study will benefit the designing and development of clothing such as sportswear.

A dynamic testing method was proposed to characterize the surface humidity of textiles under simulated windy conditions.

Robotic arm control is challenging due to the intrinsic nonlinearity. Proportional-integral-derivative (PID) controllers prevail in many robotic arm applications. However, it is usually nontrivial to tune the parameters in a PID controller. This paper aims to propose a model-based control strategy of robotic arms.

A Takagi–Sugeno (T-S) fuzzy model, which is capable of approximating nonlinear systems, is used to describe the dynamics of a robotic arm. Model predictive control (MPC) based on the T-S fuzzy model is considered, which optimizes system performance with respect to a user-defined cost function.

The control gains are optimized online according to the real-time system state. Furthermore, the proposed method takes into account the input constraints. Simulations demonstrate the effectiveness of the fuzzy MPC approach. It is shown that asymptotic stability is achieved for the closed-loop control system.

The T-S fuzzy model is discussed in the modeling of robotic arm dynamics. Fuzzy MPC is used for robotic arm control, which can optimize the transient performance with respect to a user-defined criteria.

According to very small dimensions of the microchannels, producing a microchannel with smooth surfaces is approximately impossible. The surface roughness can have a specific effect on microchannel performances. This paper aims to investigate the changes in friction and pressure drop in the microchannels by considering the different roughness elements on microchannel wall and changes in elementary geometry and flow conditions. Results show a significant effect of roughness on the pressure drop and friction.

Two-dimensional fluid flow in the rough microchannels is analyzed using FLUENT. Microchannels have a height of 50 µm. Water at room temperature (25°C) has been used as working fluid. The Reynolds numbers are considered in laminar flow range and from 50 to 300.

The results show that the value of friction factor reduces nonlinearly with an increase in Reynolds number. But, the pressure drops and the Poiseuille number in the microchannels increase with an increase in Reynolds number. The values of the pressure drop and the friction factor increase by increasing the height and size of the roughness elements, but these values reduce with an increase in the distance of roughness elements.

The roughness elements types in this research are rectangular, trapezoidal, elliptical, triangular and complex (composed of multiple types of roughness elements). The effects of the Reynolds number, roughness height, roughness distance and roughness size on the pressure drop and friction in the rough microchannels are investigated and discussed. Furthermore, differences between the effects of five types of roughness elements are identified.

The purpose of this study is to explore the seismic damage mechanism of the Dayemaling Bridge during the Maduo earthquake and discuss the seismic damage characteristics of the high-pier curved girder bridge.

In this study, the numerical simulation method is used to analyze the seismic response using synthetic near-field ground motion records.

The near-field ground motion of the Maduo earthquake has an obvious directional effect, it is more likely to cause bridge seismic damage. Considering the longitudinal slope of the bridge and adopting the continuous girder bridge form, the beam end displacement of the curved bridge can be effectively reduced, and the collision force of the block and the bending moment of the pier bottom are reduced, so the curved bridge with longitudinal slope is adopted.

Combined with the seismic damage phenomenon of bridges in real earthquakes, the seismic damage mechanism and vulnerability characteristics of high-pier curved girder bridges are discussed by the numerical simulation method, which provides technical support for the application of such bridges in high seismic intensity areas.

The purpose of this study was to examine students’ innovation capability in virtual team projects from the COVID-19 pandemic era.

The researchers conducted an empirical study and the data were collected from a total of 308 participants engaging in virtual team projects. A structural equation modeling (SEM) was used to assess the relationship of the conceptual framework.

The findings showed that virtual team culture positively influenced propensity to innovate. Also, knowledge management and communication influenced propensity to innovate through the mediation of support for innovation.

Developing a strategy for propensity to innovate in any organization demands that project team members should be able to seamlessly communicate. Developing knowledge management, communication and support for innovation strategy in a virtual team may prepare an organization for permanently different post-pandemic events and the future turbulent business environment.

This study highlights innovation capability for the propensity to innovate, a topic that is not widely researched, especially in the context of virtual teams.