Model for efficiency optimization of electric elevator drive is presented in this paper. It combines two strategies for efficiency optimization: Loss model control and Search control. Search control technique is used in a steady state of drive and loss model during transient processes. As a result, power and energy losses are reduced, especially when load torque is significant less related to i...

Two of the important parameters in grinding operation are surface roughness of the workpiece and the amount of consumed energy. These parameters are strongly affected by the condition of grinding wheel surface which is dependent on the dressing parameters. Predicting the roughness of the grinding wheel surface after dressing with known dressing parameters can improve the grinding process. Resea...

BACKGROUND Sickle cell anemia is associated with a hypercoagulable state that may lead to alterations in a coagulation profile. Measurements of coagulation factors are known to have some predictive value for clinical outcome. OBJECTIVES To determine the coagulation profile of children with SCA in steady state and crisis and compare it with those with normal HbAA genotype. MATERIALS AND METH...

in thermal cracking plants, it is desired to apply an optimal temperature profile along the reactor to minimize the operation cost. in this article a simulator is developed by the use of a mathematical model, which describes the static operation of a naphtha thermal cracking pilot plant. the model is used to predict the steady state profiles of the gas temperature and product yields. using a dy...

a theoretical solution is presented for the forced convection heat transfer of a viscoelastic fluid obeying the giesekus constitutive equation in a concentric annulus under steady state, laminar, and purely tangential flow. a relative rotational motion exists between the inner and the outer cylinders, which induces the flow. a constant temperature was set in both cylinders, in this study. the f...

Sequences based on the distant dipolar field (DDF) have shown great promise for novel spectroscopy and imaging. Unless spatial variation in the longitudinal magnetization, Mz(s), is eliminated by relaxation, diffusion, or spoiling techniques by the end of a single repetition, unexpected results can be obtained due to spatial harmonics in the steady state MzSS(s) profile. This is true even in a ...

We perform experimental measurements of the instantaneous velocity profile of the flowing layer during granular avalanches. In the pile depth, the velocity profile follows a pure exponential decrease in contrast with steady flows that are known to exhibit a well developed upper linear part. The velocity profile in the pile width is a plug flow with two exponential boundary layers at the walls. ...