Convergence Rate of Sample Mean for φ\varphi-Mixing Random Variables with Heavy-Tailed Distributions

This article studies the convergence rate of the sample mean for $\varphi$-mixing dependent random variables with finite means and infinite variances. Dividing the sample mean into sum of the average of the main parts and the average of the tailed parts, we not only obtain the convergence rate of the sample mean but also prove that the convergence rate of the average of the main parts is faster than that of the average of the tailed parts

Numerical investigation of cavitation in twin-screw pumps

In order to investigate the flow characteristics and the formation process of cavitation in twin-screw pumps, three-dimensional computational fluid dynamics numerical analysis has been carried out. A conformal structured moving mesh generated by an in-house code SCORG was applied for the rotor domain. The volume of fluid method has been adopted for dealing with the liquid-gas two-phase flow, while the bubble dynamics was handled by a homogenous cavitation model. By changing the rotation speed and discharge pressure, the intensity, distribution area and variation of cavitation at different rotor angle were obtained. The effects of rotation speed and discharge pressure on cavitation characteristics have been analysed. Calculation results with cavitation model are compared with the results without cavitation and the experimentally obtained values. The influence of cavitation on the performance of a screw pump in terms of the mass flow rate, pressure distribution, rotor torque and the shaft power has been analysed and discussed. For analysis of cavitation in clearances, a 2D numerical model which includes radial and inter-lobe clearances was used. The relationship between volumetric efficiency and cavitation intensity was developed by variation of boundary conditions

Effects of fermented wheat-rice distillers dried grains with solubles on meat quality and amino acid profile in broilers

The aim of this experiment was to evaluate the effects of replacing distillers dried grains with solubles (DDGS) with fermented DDGS (FDDGS) on meat quality and serum amino acid profiles in Chinese yellow broilers. Forty-eight 42-day-old male Chinese yellow broilers were randomly allotted to the treatments. Each treatment was replicated six times with four birds per replicate. Both groups received a basal corn-soybean diet that was supplemented with either 20% DDGS or 20% FDDGS. Broilers were euthanized at 70 days old. The right half of each breast was evaluated for meat quality. Both breast and thigh meats were evaluated for proximate and fatty acid composition. Serum from blood samples was analysed to quantify relative amounts of free amino acids. Breast meat from broilers supplemented with FDDGS had a lower pH and less drip loss than those supplemented with DDGS (P <0.05). No differences were detected between treatments in the proximate composition of breast and thigh meat (P >0.05). Myristic acid (C14:0) concentration of thigh muscles was reduced for broilers supplemented with FDDGS compared with those supplemented with DDGS (P＜0.05). Concentrations of lysine, taurine, alpha-aminoadipic acid, glycine, and 3-methylhistidine in serum were all lower for broilers supplemented with FDDGS than for those supplemented with DDGS (P＜ 0.05). Meanwhile, the serum phosphoserine concentration of the FFDS-supplemented broilers was greater than those supplemented with DDGS (P＜0.05). In conclusion, replacing 20% DDGS with a like amount of FDDGS can be recommended for diets of growing broiler chickens.Keywords: fatty acids, meat quality, shear forc

Conduction mechanisms of epitaxial EuTiO3 thin films

To investigate leakage current density versus electric field characteristics, epitaxial EuTiO3 thin films were deposited on (001) SrTiO3 substrates by pulsed laser deposition and were post-annealed in a reducing atmosphere. This investigation found that conduction mechanisms are strongly related to temperature and voltage polarity. It was determined that from 50 to 150 K the dominant conduction mechanism was a space-charge-limited current under both negative and positive biases. From 200 to 300 K, the conduction mechanism shows Schottky emission and Fowler-Nordheim tunneling behaviors for the negative and positive biases, respectively. This work demonstrates that Eu3+ is one source of leakage current in EuTiO3 thin films.Comment: 17 pages,4 figures, conferenc

Kinetics analysis of solidification process of 1035 steel at different cooling rates

It is of great theoretical significance to study the solidification kinetics of metal materials for improving the microstructure and properties. In this paper, the Differential Scanning Calorimetry (DSC) was used to measure the enthalpy change of solidification process of 1035 steel at different cooling rates. The activation energy of the solidification process was determined by the equal conversion method based on the data of enthalpy. The mechanism function of the solidification process was also determined. It is shown that the value of the activation energy of solidification process varied with the solidification fraction, and the mechanism functions of solidification process are different in different temperature ranges, which are –ln(1– α) for 1 504-1 502 °C –ln(1–α)1/2 for 1 500-1 942 °C and –ln(1– α)2/5 for_1 490 °C respectively