Selective Error Correction Research Articles

Reducing EFL Learners’ Speaking Anxiety through Selective Error Correction and Group Work

This quantitative study aimed to examine the level of speaking anxiety experienced by second-year high-school Acehnese EFL learners in their oral performance in L2 classroom and to investigate the attempt to lower their anxiety through the implementation of selective error correction and group work. The Foreign Language Speaking Anxiety Scale (Horwitz et al., 1986) was used as a means to survey and evaluate the learners’ speaking anxiety, and their oral performance was assessed through speaking performance rubric as adopted from Ismailia (2021) before and after the learners’ exposure to selective error correction and group work. The findings showed that a high level of speaking anxiety was found in the majority of the learners, and that the use of selective error correction and group work for the treatment of speaking anxiety overall resulted in the learners’ improved performance in their oral task. The findings highlighted the needs to create a positive and supportive educational environment that stimulates learners to freely experiment with L2 and to establish close-knit learning communities that promote authentic interactions in L2 and provide opportunities to be more engaged in oral language use.

Kinetics of DNA strand transfer between polymerase and proofreading exonuclease active sites regulates error correction during high-fidelity replication

We show that T7 DNA polymerase (pol) and exonuclease (exo) domains contribute to selective error correction during DNA replication by regulating bidirectional strand transfer between the two active sites. To explore the kinetic basis for selective removal of mismatches, we used a fluorescent cytosine analog (1,3-diaza-2-oxophenoxazine) to monitor the kinetics of DNA transfer between the exo and pol sites. We globally fit stopped-flow fluorescence and base excision kinetic data and compared results obtained with ssDNA versus duplex DNA to resolve how DNA transfer governs exo specificity. We performed parallel studies using hydrolysis-resistant phosphorothioate oligonucleotides to monitor DNA transfer to the exo site without hydrolysis. ssDNA binds to the exo site at the diffusion limit (109M-1 s-1, Kd = 40 nM) followed by fast hydrolysis of the 3'-terminal nucleotide (>5000s-1). Analysis using duplex DNA with a 3'-terminal mismatch or a buried mismatch exposed a unique intermediate state between pol and exo active sites and revealed that transfer via the intermediate to the exo site is stimulated by free nucleoside triphosphates. Transfer from the exo site back to the pol site after cleavage is fast and efficient. We propose a model to explain why buried mismatches are removed faster than single 3'-terminal mismatches and thereby provide an additional opportunity for error correction. Our data provide the first comprehensive model to explain how DNA transfer from pol to exo active sites and back again after base excision allow efficient selective mismatch removal during DNA replication to improve fidelity by more than 1000-fold.

Reducing EFL Learners’ Speaking Anxiety through Selective Error Correction and Group Work

This quantitative study aimed to examine the level of speaking anxiety experienced by second-year high-school Acehnese EFL learners in their oral performance in L2 classroom and to investigate the attempt to lower their anxiety through the implementation of selective error correction and group work. The Foreign Language Speaking Anxiety Scale (Horwitz et al., 1986) was used as a means to survey and evaluate the learners’ speaking anxiety, and their oral performance was assessed through speaking performance rubric as adopted from Ismailia (2021) before and after the learners’ exposure to selective error correction and group work. The findings showed that a high level of speaking anxiety was found in the majority of the learners, and that the use of selective error correction and group work for the treatment of speaking anxiety overall resulted in the learners’ improved performance in their oral task. The findings highlighted the needs to create a positive and supportive educational environment that stimulates learners to freely experiment with L2 and to establish close-knit learning communities that promote authentic interactions in L2 and provide opportunities to be more engaged in oral language use.

REDUCING EFL LEARNERS’ SPEAKING ANXIETY THROUGH SELECTIVE ERROR CORRECTION AND GROUP-WORK STRATEGIES

This quantitative study aimed to examine the level of speaking anxiety experienced by second-year high-school Acehnese EFL learners in their oral performance in L2 classroom and to investigate the attempt to lower their anxiety through the implementation of selective error correction and group work. The Foreign Language Speaking Anxiety Scale (Horwitz et al., 1986) was used as a means to survey and evaluate the learners’ speaking anxiety, and their oral performance was assessed through speaking performance rubric before and after the learners’ exposure to selective error correction and group work. The findings showed that a high level of speaking anxiety was found in the majority of the learners, and that the use of selective error correction and group work for the treatment of speaking anxiety overall resulted in the learners’ improved performance in their oral task. The findings highlighted the needs to create a positive and supportive educational environment that stimulates learners to freely experiment with L2 and to establish close-knit learning communities that promote authentic interactions in L2 and provide opportunities to be more engaged in oral language use.

Power‐efficient error‐resilient network‐on‐chip router using selective error correction code scheme

In this Letter, a new error-resilient router design for network-on-chips (NoCs) is proposed to effectively address various transient errors considering power efficiency and implementation complexity. To cope with the most probable error conditions, a selective error correction code (ECC) is embraced in router design, which combines an optimised double-bit error-correcting Bose–Chaudhuri–Hocquenghem (BCH) code and a single-bit error-correcting Hamming code. To reduce the inherent delay overhead of the BCH code, the parallel BCH coding scheme is designed and implemented into the proposed router. Furthermore, the associated ECC controller is designed for switching into an appropriate ECC mode without an additional delay at runtime. The proposed router is synthesised using 28 nm CMOS technology. Experimental results with a variety of common error conditions show that the proposed method improves the average latency by up to 13.8% and achieves up to 11.5% power reduction with the area increase of 5.7%, when compared to the conventional error correction scheme.

High-Density Image Storage Using Approximate Memory Cells

This paper proposes tailoring image encoding for an approximate storage substrate. We demonstrate that indiscriminately storing encoded images in approximate memory generates unacceptable and uncontrollable quality degradation. The key finding is that errors in the encoded bit streams have non-uniform impact on the decoded image quality. We develop a methodology to determine the relative importance of encoded bits and store them in an approximate storage substrate. The storage cells are optimized to reduce error rate via biasing and are tuned to meet the desired reliability requirement via selective error correction. In a case study with the progressive transform codec (PTC), a precursor to JPEG XR, the proposed approximate image storage system exhibits a 2.7x increase in density of pixels per silicon volume under bounded error rates, and this achievement is additive to the storage savings of PTC compression.

High-Density Image Storage Using Approximate Memory Cells

This paper proposes tailoring image encoding for an approximate storage substrate. We demonstrate that indiscriminately storing encoded images in approximate memory generates unacceptable and uncontrollable quality degradation. The key finding is that errors in the encoded bit streams have non-uniform impact on the decoded image quality. We develop a methodology to determine the relative importance of encoded bits and store them in an approximate storage substrate. The storage cells are optimized to reduce error rate via biasing and are tuned to meet the desired reliability requirement via selective error correction. In a case study with the progressive transform codec (PTC), a precursor to JPEG XR, the proposed approximate image storage system exhibits a 2.7x increase in density of pixels per silicon volume under bounded error rates, and this achievement is additive to the storage savings of PTC compression.

SECRET

DRAMs are used as the main memory in most computing systems today. Studies show that DRAMs contribute to a significant part of overall system power consumption. One of the main challenges in low-power DRAM design is the inevitable refresh process. Due to process variation, memory cells exhibit retention time variations. Current DRAMs use a single refresh period determined by the cell with the largest leakage. Since prolonging refresh intervals introduces retention errors, a set of previous works adopt conventional error-correcting code (ECC) to correct retention errors. However, these approaches introduce significant area and energy overheads. In this article, we propose a novel error correction framework for retention errors in DRAMs, called SECRET (selective error correction for refresh energy reduction). The key observations we make are that retention errors are hard errors rather than soft errors, and only few DRAM cells have large leakage. Therefore, instead of equipping error correction capability for all memory cells as existing ECC schemes, we only allocate error correction information to leaky cells under a refresh interval. Our SECRET framework contains two parts: an offline phase to identify memory cells with retention errors given a target error rate and a low-overhead error correction mechanism. The experimental results show that among all test cases performed, the proposed SECRET framework can reduce refresh power by 87.2% and overall DRAM power up to 18.57% with negligible area and performance overheads.

Effects of Overall, Selective, and No Error Correction on the Quality and Quantity of EFL Students' Writing

The purpose of this study is to compare the effects of overall, selective, and no error correction on the quality and quantity of English as a Foreign Language (EFL) students' writing. A total of 107 secondary school students in 3 classes participated in this study. These classes were randomly assigned to the three treatment conditions: overall error correction, where the teacher corrected all grammatical, mechanical, and organizational errors on each composition; selective error correction where the teacher corrected only two types of errors on the composition; and the no error correction where the students received no error correction at all. The study lasted for 22 weeks with one 2 week interruption for a winter vacation. There were pre- and post-tests of composition writing. The data were analyzed using the one-way analysis of variance and the t-test. The pretest results showed no significant differences in the mean scores among the three groups. The post-test results revealed significant differences among the three groups, favoring the selective error correction group. Selective error correction improves not only the quality and quantity of EFL students' writing, but supports the contention that errors should not be left uncorrected in the hope that they will correct themselves naturally but not so much that they demoralize the learners and put them on the defensive.

Stochastic Methods for Sequential Data Assimilation in Strongly Nonlinear Systems

This paper considers several filtering methods of stochastic nature, based on Monte Carlo drawing, for the sequential data assimilation in nonlinear models. They include some known methods such as the particle filter and the ensemble Kalman filter and some others introduced by the author: the second-order ensemble Kalman filter and the singular extended interpolated filter. The aim is to study their behavior in the simple nonlinear chaotic Lorenz system, in the hope of getting some insight into more complex models. It is seen that these filters perform satisfactory, but the new filters introduced have the advantage of being less costly. This is achieved through the concept of second-order-exact drawing and the selective error correction, parallel to the tangent space of the attractor of the system (which is of low dimension). Also introduced is the use of a forgetting factor, which could enhance significantly the filter stability in this nonlinear context.