The cure process of epoxy prepreg used as composite pipe joints was studied by means of differential scanning calorimetry (DSC), Bohlin Rheometer and other techniques. Isothermal DSC measurements were conducted between 110 and 220 C, at 10 C intervals. The results show that the complete cure reaction could be achieved at 220 C. The isothermal cure process was simulated with the four-parameter a...

Cure models for clustered survival data have the potential for broad applicability. In this paper, we consider the mixture cure model with random effects and propose several estimation methods based on Gaussian quadrature, rejection sampling, and importance sampling to obtain the maximum likelihood estimates of the model for clustered survival data with a cure fraction. The methods are flexible...

We propose a semiparametric method for the analysis of masked-cause failure data that are also subject to a cure. We present estimators for the failure time distribution, the cure rate, and the covariate effect on each of these, assuming a proportional hazards cure model for the time to event of interest and we use the expectation-maximization algorithm to conduct the likelihood maximization. T...

effect of partial natural rubber replaced with synthetic rubbers, styrene butadiene and cis butadiene, on failure and strength properties of bias tread nr/br based compound was studied by efficient and conventional sulfur curing systems and mixtures of different carbon black grades. it was observed that failure behavior comprising tear resistance and crack growth in substituted compounds droppe...

Heat generation in an exothermic reaction during the curing process and low thermal conductivity of the epoxy resin produces high peak temperature and temperature gradients which result in internal and residual stresses, especially in large epoxy samples. In this paper, an optimization algorithm was developed and applied to predict the thermal cure cycle to minimize the temperature peak and the...

background: chronic illnesses are by definition long lasting and without a definitive cure. in iran, like in many other developing countries, chronic diseases are not merely diseases of the elderly. they also affect a much higher proportion of people during their prime working years and more so than in the developed countries. therefore, it is essential to understand the factors influencing the...

Employer’s Information and Promotion-Seeking Activities This paper presents a model in which promotion of employees within the internal firm hierarchy is determined by the individuals’ allocation of time between promotion/rent-seeking and productive activity. We consider the effect of an increase in the employer’s knowledge (information) regarding the employees’ productivity levels on the total...

The choice of a suitable material model to simulate process induced distortions is important in order achieve right first time approach the design new moulds. This work investigates ability Cure Hardening Instantaneously Linear Elastic (CHILE) and linear viscoelastic predict an aerospace composite frame. models were coupled with cure kinetics chemical shrinkage capture multi-physics phenomena t...