background and objectives: lactobacillus delbrueckii ssp bulgaricus is widely used in dairy industries as a starter for yogurt production. this study was designed using response surface methodology (rsm) in 12 batch ph-controlled cultures of lactobacillus delbrueckii sub-ssp. bulgaricus for determining the effect of temperature and ph on the biomass production of a native strain of l. bulgaricu...

this paper presents an overview of model updating and particularly its application for updating of frame model. in this article a mathematical model of the frame was produced with finite element method. the frame was subjected to hammer modal testing. then the results of the modal testing were compared with those predicted with the model. this comparison revealed discrepancies between these two...

the modified surface of typha latifolia l. root (mstl), as an alternative economical adsorbent, wasused for the removal of ni (ii) and cd(ii) ions from aqueous solutions. the effect of initial ph, initialconcentration of metal ion, and contact time was investigated in a batch system at room temperature.the kinetics data could be fitted well by pseudo-second-order model with correlation coeffici...

this study aims at presenting a numerical model for predicting grout flow and penetration length into the jointed rock mass using universal distinct element code (udec). the numerical model is validated using practical data and analytical method for grouting process. input data for the modeling, including geomechanical parameters along with grout properties, were obtained from a case study. the...

this paper reports the results of an experimental study on non-native production of english vowels. two groups of persian efl learners varying in language proficiency were tested on their ability to produce the nine plain vowels of american english. vowel production accuracy was assessed by means of acoustic measurements. ladefoged and maddison’s (1996) f1 f2 measurements for american english v...

great effect of three way catalytic convertor (twc) performance on oxygen sensor output voltage has made the sensor (located after catalyst) as the main signal in almost all today’s twc monitoring algorithms. in this paper output voltage of nonlinear oxygen sensor is estimated using a nonlinear autoregressive with exogenous inputs (narx) model. the estimation uses ecu calculated exhaust gas flo...

a new model is proposed in this research to calculate the longitudinal strengthof unidirectional e-glass reinforced polymer composites exposed to sulfuricacid environment, using a micromechanics model. in the proposed method,it is assumed that the residual strength of the degraded composites under acidic environment can be calculated by knowing the degraded strength properties of the constituen...

climate change is found to be the most important global issue in the 21st century, so to monitor its trend is of great importance. atmospheric general circulation models because of their large scale computational grid are not able to predict climatic parameters on a point scale, so small scale methods should be adapted. among downscaling methods, statistical methods are used as they are easy to...

background & aim: esophageal cancer is one of the main common causes of death. the high prevalence of esophageal cancer in northern iran is an important public health problem. the main aim of this paper was to assess the factors affecting survival of  atients with esophageal cancer in neighbor provinces around the caspian sea using weibull mixture cure model and mixture cure model based on a no...

background: despite their simplicity and the low-cost, the conventional non-contact uv systems have low efficiency in water disinfection. the purpose of this study was to examine the possibility of upgrading these systems by some modifications in order to maximize the water contact with the uv radiation and as a result a better disinfection.    methods: in this study, two enhanced models of non...