This study aimed at comparing the impact of two types of teacher feedback on Iranian EFL learners’ writing ability and their verb tense consistency in L2 writing. Following the administration of a standardized language proficiency test (Preliminary English Test), sixty-two participants were selected and were randomly assigned to the control (direct-only correction) and experimental (direct metalinguistic correction) groups. The comparison of the groups on the pre-test observation confirmed the homogeneity of the subjects before the instruction. During the study, the control group (direct-only correction) received some feedback on the location of errors along with the correct form of errors. The experimental group (direct metalinguistic correction), however, received the same type of feedback plus metalinguistic comments explaining the reason behind the errors. After the treatment, both groups took a post and a delayed post-test. The results of the study showed that direct metalinguistic correction was more effective than direct-only correction in improving EFL learners’ writing ability. The study also showed that the effect of instruction lasted over time.

The free vibrations of a rod are governed by a differential equation of the form $(a(x)y^\prime)^\prime+\lambda a(x)y(x)=0$, where $a(x)$ is the cross sectional area and $\lambda$ is an eigenvalue parameter. Using the finite element method (FEM) we transform this equation to a generalized matrix eigenvalue problem of the form $(K-\Lambda M)u=0$ and, for given $a(x)$, we correct the eigenvalues $\Lambda$ of the matrix pair $(K,M)$ to approximate the eigenvalues of the rod equation. The results show that with step size $h$ the correction technique reduces the error from $O(h^2i^4)$ to $O(h^2i^2)$ for the $i$-th eigenvalue. We then solve the inverse spectral problem by imposing numerical algorithms that approximate the unknown coefficient $a(x)$ from the given spectral data. The cross section is obtained by solving a nonlinear system using Newton's method along with a regularization technique. Finally, we give numerical examples to illustrate the efficiency of the proposed algorithms.

This paper develops a flux-linkage estimator using voltage model in stator reference based on an improved integrator with DC-offset PI-correction loop having the reference flux magnitude in the correction error. The DCoffset and drift from acquisition channels and the flux-vector initial error are canceled. A phase locked-loop state estimator extracts the speed and position from the estimated rotor flux. This robust solution can be applied in all AC drives with sinusoidal flux distribution in wide speed range, including sensorless control. A sensorless DTC is investigated for both PMSM and IM drives. Simulation results for PMSM drive and also experimental results for IM drive prove highdynamic performances in large speed range step reversal, for zero to rated load-torque step.

Direct orthogonal signal correction(DOSC) and Savitzky-Golay filters (SGF) were applied as preprocessing methods on the original and first derivative absorbance data. Principle component regression (PCR), partial least squares (PLS) and iterative target transformation factor analysis (ITTFA), were used in spectrophotometric simultaneous determination of heavy divalent metal ions, lead, zinc, mercury and cadmium, using 4-(2-pyridylazo) resorcinol (PAR) as metallochromic indicator. The optimum values of the parameters for DOSC and SGF were obtained according to REP, R2 and RMSEP functions for calibration and prediction sets. The concentration for Hg2+, Pb2+, Zn2+ and Cd2+ ions in calibration set were varied between 0 - 12.24, 0 - 9.81, 0 - 0.87 and 0-3.96 ppm, respectively. The experimental calibration set was composed of 35 sample solutions and the 7 solutions as prediction set using a simple lattice (4, 4) mixture design. The absorption spectra were recorded from 450 to 600 nm and absorbance data were autoscaled. The effect of pH on the sensitivity and selectivity was studied in the range of 1.00 - 11.00 and pH=7.50 was chosen according to net analyte signal (NAS) as a function of pH.

There was a misprint in the title of published article: The Eeffect of Metformin Combined with Calcium-Vitamin D3 Against Diet-Induced Nonalcoholic Fatty Liver Disease. Adv Pharm Bull, 2018, 8(1), 97-105. doi: 10. 15171/ apb. 2018. 012. 1 In the title of this article, the word “ Eeffect” was corrected to “ Effect” . The correct title of the article is: The Effect of Metformin Combined with Calcium-Vitamin D3 Against Diet-Induced Nonalcoholic Fatty Liver Disease