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As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high‐resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints model while considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U‐shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within‐group exploitation competition in wild rhesus macaques. Highlight: By applying GPS collars, we assessed home range quality and space utilization for 22 rhesus macaques in six groups.Our results offered supportive evidence for the ecological constraints model, indicating that within‐group exploitation feeding competition is the predominant factor influencing macaques' space use on Neilingding Island. [ABSTRACT FROM AUTHOR]

The correlation between strain rates and the mechanical properties of HTPB propellant with 90% solid content (mass fraction) was investigated by uniaxial tensile tests at different tensile rates, and the tensile fracture surface was observed by scanning electron microscope (SEM). The effects of strain rate on the mechanical properties and failure mechanisms of the propellant were analyzed. The results show that the stress--strain curve of the propellant appears an arc segment phenomenon at low tensile rates. With the increase of tensile rates, the stress--strain curves of propellant gradually changes from 5 segment to 4 segment. The initial modulus and the maximum tensile strength of the propellant show an increasing trend with an increase in the tensile rates. The maximum elongation of the propellant decreases with an increase in the strain rate, and the maximum elongation of propellant is only 33.9% when the strain rate is 1 190.48 X 10 4s 1 . With the increase of strain rate, the failure mechanism of propellant gradually changes from particle dehumidification to matrix tearing, without particle fragmentation. [ABSTRACT FROM AUTHOR]

The meso-damage evolution behavior of composite solid propellant is summarized. The research progress of meso-damage evolution of composite solid propellants is reviewed from three main aspects: the characterization method of meso-damage evolution, the finite element numerical simulation of meso-damage evolution and the viscoelastic constitutive model with damage. The shortcomings of current research and future research directions are pointed out. It was indicated that in the microscopic characterization aspect, it is difficult to realize the meso-damage characterization analysis under dynamic and complex loads, and new micro-scopic characterization methods need to be developed to improve the dynamic multi-scale observation means to solve the problem of quantitative damage characterization. In the numerical simulation aspect, the two-dimensional RVE model and the interface model only applicable to a single load cannot reflect the real meso-damage evolution, and a three-dimensional RVE model, which can reflect the mesoscopic structure, and an interface model considering the effects of temperature and strain rate need to be established to obtain the accurate mesoscopic damage evolution process of propellant. In terms of constitutive model with damage, most of the phenomenological based constitutive models are unable to reflect the impact of mesoscopic structural changes on the mechanical response. A macroscopic and mesoscopic constitutive model needs to be developed to predict the mechanical response of propellant at mesoscopic scale. 73 References are attached. [ABSTRACT FROM AUTHOR]

This study concerns small and medium-sized enterprise (SME) suppliers suffering from cash constraints in operations, money shortages with possible disruptions and cost uncertainty because of the distributor's supply risk and the information asymmetry. Thus, this study adopts the distributor's (buyer's) perspective and applies a credit guarantee mechanism with an incentive contract as a risk management tool. The distributor can adopt incentive contracts to reveal the type of its supplier; the higher the inefficient supplier's contribution to the distributor, the smaller the gap between procurement contract quantities with the efficient supplier and procurement contract quantities with the inefficient supplier. An insight into practice is that incentive contracts are tools for acquiring ideal suppliers in the supply base and help companies such as Li & Fung enhance their competitive capabilities. [ABSTRACT FROM AUTHOR]

When a stable solute-stratified fluid in a vertical slot is imposed with a horizontal temperature gradient, it becomes double-diffusively unstable when the critical condition is exceeded. We conduct a comprehensive three-dimensional stability analysis to investigate the double-diffusive stability with emphasis on the effects of the Prandtl number P r and the Lewis number L e. The results show that the stability is characterized by five stability modes and seven transitions at which the mode changes from one to another. The occurrence of stability modes and transitions largely depends upon P r and L e. An extensive comparison between the present results and those of previous analytical and experimental studies is made. The comparison confirms that the present results are in excellent agreement with the asymptotic solutions proposed by Thorpe et al. [J. Fluid Mech. 38, 375–400 (1969)] and Kerr and Tang [J. Fluid Mech. 392, 213–232 (1999)]. It explains why most of the observed flows were predominated by salt-finger convection. [ABSTRACT FROM AUTHOR]

This work aims to examine the relationship between global economic policy uncertainty (GEPU) and tourism activities in the fragile five (F5) countries, namely, Brazil, India, Indonesia, South Africa and Turkey using three-dimensional wavelet transforms context structures and the annual data during the period of 1997–2018. This innovative technique allows the decomposition of time-series at different time frequencies. In this work, the researchers used three-dimensional continuous wavelets based on Granger causality analysis to investigate the relationship between GEPU and tourism. The finding shows that the relationship generally changes over time, displaying low to high frequency cycles. Moreover, the timing and frequency change when GEPU co-moves with tourism. Accordingly, it can be recommended that the government increase and promote tourism demand and further provide and nurture the expansion of tourism supply. [ABSTRACT FROM AUTHOR]