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The purpose of this paper is to model the aircraft-cargo’s coupling dynamics during ultra-low altitude heavy cargo airdrop and to design the aircraft’s robust flight control law counteracting its aerodynamic coefficients perturbation induced by ground effect and the disturbance from the sliding cargo inside.

Aircraft-cargo system coupling dynamics model in vertical plane is derived using the Kane method. Trimmed point is calculated when the cargo fixed in the cabin and then the approximate linearized motion equation of the aircraft upon it is derived. The robust stability and robust H_∞ optimal disturbance restraint flight control law are designed countering the aircraft’s aerodynamic coefficients perturbation and the disturbance moment, respectively.

Numerical simulation shows the effectiveness of the proposed control law with elevator deflection as a unique control input.

The model derived and control law designed in the paper can be applied to heavy cargo airdrop integrated design and relevant parameters choice.

The dynamics model derived is closed, namely, the model can be called in numerical simulation free of assuming the values of parachute’s extraction force or cargo’s relative sliding acceleration or velocity as seen in many literatures. The modeling is simplified using Kane method rather than Newton’s laws. The robust control law proposed is effective in guaranteeing the aircraft’s flight stability and disturbance restraint performance in the presence of aerodynamic coefficients perturbation.

To date there is little understanding of the factors that impact the survival of foreign IPOs after they list on US stock exchanges. In this study, we examine how foreign IPO survival is contingent on institutional factors associated with the firm’s home country. We also explore how corporate governance and organizational identity influence the survival of foreign IPOs in the United States. Results suggest that the US institutional environment supports foreign firms with more independent and professional leadership, and that knowledge-intense organizations have higher chances of long-term success after listing on US exchanges.

The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.

The authors prepared MUF resin with different F/(M + U) and changed the amount of melamine added, through the analysis of MUF resin properties to get the best reaction parameters, and used different amino acid cure systems including NH₄Cl cured the resin.

Resin’s heat resistance and water resistance are mainly determined by the amount of melamine added, and formaldehyde emission of the plywood can be changed by adjusting F/(M + U). The peak temperature of the curing agent-cured resin increases as compared with the self-curing resin. Stronger the acidity of curing agent, faster the viscosity increased in probation period and lower the bonding strength and heat resistance of the resin.

Melamine improves the heat resistance and water resistance of the resin. When the amount of melamine is more than a certain value, water resistance of the resin decreased.

MUF resin that is resistant to boiling water and exhibits low formaldehyde emission can be used in high temperature, high humidity and strict formaldehyde emission environment and can also be combined with other materials.

It was helpful to reduce the effect of formaldehyde emission on people’s health and environmental pollution and is also beneficial for the expansion of the application range of aldehyde resin.

The originality is twofold: the influence of the acid strength of curing agent on the bonding strength of the resin adhesive and the method for preparing high performance MUF resin by following the traditional process.

This paper aims to investigate the delamination wear properties of a carbon strip in a carbon strip rubbing against a copper wire at the high-sliding speed (380 km/h) with or without electrical current.

The friction and wear properties of a carbon strip in a carbon strip rubbing against a copper wire are tested on the high-speed wear tester whose speed can reach up to 400 km/h. The test data have been collected by the high-speed data collector. The worn surfaces of the carbon strip are observed by the scanning electron microscope.

It was found that there was a significant increase of the delamination wear with the decrease of the normal load when the electric current is applied. The size of the flake-like peeling also increases with the decrease of normal load. The delamination wear extends gradually from the edge of the erosion pits to the surrounding area with the decrease of the normal load. However, the delamination wear never appears in the absence of electric current. It is proposed that the decreased normal load and the big electrical current are the major causes of the delamination wear of the carbon strip.

The experimental test at high-sliding speed of 380 km/h was performed for the first time, and the major cause of the delamination was discovered in this paper.

The purpose of the study was to assess the relationship between child sexual abuse (CSA) and posttraumatic stress disorder (PTSD) in female inmates in China. A total of 471 participants were assessed for CSA, personality traits, coping strategies, and frequency of lifetime PTSD. Results demonstrated that CSA and negative coping were predictive factors for lifetime PTSD among female inmates after personality traits were controlled. The findings suggest that CSA is one potential factor contributing to lifetime PTSD among female inmates. The importance of screening for CSA among female inmates was highly emphasized. Early intervention and prevention programmes based on coping skills may be useful to forestall the development of chronic PTSD in female inmates.

This study aims to delve upon customer satisfaction and service quality within small- and medium-sized hotels (SMSHs) by using a modified SERVQUAL model.

Data for the study were collected from a sample of 253 guests of varying nationalities who stayed at SMSHs of one-to-three-star ratings in the UAE. Moreover, 15 face-to-face interviews were conducted. The influence of the five dimensions of the SERVQUAL model on visitors’ satisfaction was explored using structural equation modelling.

The results indicated that three out of the five dimensions of SERVQUAL, namely, tangible, responsiveness and assurance, have significant positive impact on visitors’ satisfaction of the SMSHs Industry. The remaining two dimensions of SERVQUAL, reliability and empathy, have no significant impact on visitors’ satisfaction.

This study provides a major contribution in that it offers the potential to examine a vastly under researched area of customer satisfaction and service quality of SMSHs in a developing country.