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The purpose of this paper is to investigate the tribological properties of MoS₂ nano‐sized hollow spheres in liquid paraffin (LP) and the corresponding action mechanism. Morever, its feasibity of industrial application as an oil additive in the industrial lubrication field is also explored.

The tribological properties of MoS₂ nano‐sized hollow spheres (NH‐MoS₂) modified by Cyanex 301(di‐(2,4,4‐trimethylpentyl) dithiophosphinic acid) with size of 200 ∼ 300 nm in LP are studied and compared with those of the commercial colloidal MoS₂ (CC‐MoS₂) on a four‐ball tester and an Optimol SRV Oscillating friction and wear tester in a ball‐on disk configuration. The worn surfaces of the lower flat disc are examined with a scanning electron microscopy and an X‐ray photoelectron spectroscopy, respectively.

Results show that NH‐MoS₂ is a better extreme‐pressure additive and anti‐wear (AW) and friction‐reducing additive in LP than CC‐MoS₂. Under the optimum concentration of 0.5 per cent for both NH‐MoS₂ and CC‐MoS₂ and the load of 400 N, the friction coefficient of NH‐MoS₂ + LP and CC‐MoS₂ + LP decreases about 43.8 and 6.3 per cent, and the wear volume loss decreases about 60.3 and 12.0 per cent compared with the pure LP. The boundary lubrication mechanism for NH‐MoS₂ + LP can be deduced as the effective chemical adsorption protective film formed by the long chain alkyls R and active elements (S and P) in the modification layer and tribochemical reaction film containing the tribochemical products of the additive. Moreover, sliding and rolling frictions co‐exist in NH‐MoS₂ + LP, doing contributions to the good tribological properties as well.

In this paper, the Cyanex 301‐modified MoS₂ nano‐sized hollow spheres with diameter of 200 ∼ 300 nm are firstly added into LP to investigate its tribological properties. The excellent AW and friction‐reducing properties indicate that this MoS₂ hollow spheres product is a good oil additive, and the fundamental data presented here will be useful for its further industrial application in the future.

Established in 1967 by the National Service (Amendment) Bill, National Service (NS) makes it compulsory for most young Singaporean males to enlist in the armed forces, typically for a two-year period. NS comes at a critical juncture in most Singaporean mens’ adolescence, disrupting their lives and isolating them in a foreign environment just as they are beginning to form a firm sense of identity. Recruits are expected to go through grueling training and endure harsh scoldings to prove their worth as both soldiers and men. Through an interview with 14 individuals who have served or are serving NS, it is found that the hegemonic masculinity present in NS relies on norms of strength, leadership, and suppression of emotion. However, its impact on enlistees is inconsistent, and dependent on one’s vocation, personal encounters, and expectations prior to enlisting.

The purpose of this paper is to enable robots to intelligently adapt their damping characteristics and motions in a reactive fashion toward human inputs and task requirements during physical human–robot interaction.

This paper exploits a combination of the dynamical system and the admittance model to create robot behaviors. The reference trajectories are generated by dynamical systems while the admittance control enables robots to compliantly follow the reference trajectories. To determine how control is divided between the two models, a collaborative arbitration algorithm is presented to change their contributions to the robot motion based on the contact forces. In addition, the authors investigate to model the robot’s impedance characteristics as a function of the task requirements and build a novel artificial damping field (ADF) to represent the virtual damping at arbitrary robot states.

The authors evaluate their methods through experiments on an UR10 robot. The result shows promising performances for the robot to achieve complex tasks in collaboration with human partners.

The proposed method extends the dynamical system approach with an admittance control law to allow a robot motion being adjusted in real time. Besides, the authors propose a novel ADF method to model the robot’s impedance characteristics as a function of the task requirements.

Rural homestays have emerged as an interesting option for tourists. This study aims to assess the role of destination attractiveness factors and travel motivations in homestay choice. The moderating role of need for uniqueness towards enhancing these relationships is also examined.

A survey of 201 Indian tourists who had visited rural homestays in the Uttarakhand state of India was conducted. Data were analyzed using SPSS and WarpPLS, based on structural equation modelling approach.

Results indicate that two destination attractiveness factors – (a) cultural and rural attractions and (b) destination location and transportation – have a significant association with rural homestay choice. Further, need for uniqueness enhances the relationship between natural attractions and choosing rural homestays.

Although there are several studies on rural homestays, there is scant research on the factors influencing the choice of rural homestays from a tourists’ perspective. Besides, studies on rural homestay tourism have not assessed the role of need for uniqueness in influencing such choices. The implications of the study for destination marketers, homestay operators and owners are discussed which would hopefully aid in attracting discerning tourists to the rural homestays to such regions.

The heat transfer properties play significant roles in the thermal comfort of the clothing products. The purpose of this paper is to find the relationship between heat transfer properties and fabrics' structure, yarn properties and predict the effective thermal conductivity of single layer woven fabrics by a parametric mathematical model.

First, the weave unit was divided into four types of element regions, including yarn overlap regions, yarn crossing regions, yarn floating regions and pore regions. Second, the number and area proportion of each region were calculated respectively. Some formulas were created to calculate the effective thermal conductivity of each element region based on serial model, parallel model or series–parallel mixing model. Finally, according to the number and area proportion of each region in weave unit, the formulas were established to calculate the fabric overall effective thermal conductivity in thickness direction based on the parallel models.

The influences of yarn spacing, yarn width, fabric thickness, the compressing coefficients of air layers and weave type on the effective thermal conductivity were further discussed respectively. In this model, the relationships between the effective thermal conductivity and each parameter are some polynomial fitting curves with different orders. Weave type affects the change of effective thermal conductivity mainly through the numbers of different elements and their area ratios.

In this model, the formulas were created respectively to calculate the effective thermal conductivity of each element region and whole weave unit. The serial–parallel mixing characteristics of yarn and surrounding air are considered, as well as the compression coefficients of air layers. The results of this study can be further applied to the optimal design of mixture fabrics with different warp and filling yarn densities or different yarn thermal properties.