Error Location Research Articles

Imaging through deep turbulence using single-shot digital holography data.

This paper uses an experimental setup consisting of phase plates and a digital-holography receiver to validate the performance of an algorithm, referred to as multi-plane iterative reconstruction (MIR), for imaging through deep turbulence. In general, deep-turbulence conditions arise from aberrations being distributed along the propagation path. The resulting phase errors then cause a multifaceted problem with multiple empirically determined limitations. To address these limitations, the MIR algorithm works by sensing and correcting for the distributed-volume phase errors using single-shot digital holography data (i.e., one speckle measurement from the coherent illumination of an optically rough extended object). As such, we first show that our distributed-volume phase errors, created using the phase plates, follow path-integrated Kolmogorov statistics for weak-to-deep turbulence strengths. We then present results from two MIR algorithm configurations: a) where we have a priori knowledge of the placement of the phase plates, so that we sense and correct in the exact locations of the phase errors, and b) where we do not have a priori knowledge of the placement of the phase plates, so that we sense and correct in two fixed planes for all phase-error combinations. Given weak-to-deep turbulence strengths, the results show that the two MIR algorithm configurations perform comparably for the four imaging scenarios tested. Such results are promising for tactical applications, where one might not have a priori knowledge of the deep-turbulence conditions.

Less is more? The impact of written corrective feedback on corpus-assisted L2 error resolution

The past decade has seen a sharp increase in research into L2 learners’ direct use of language corpora (typically known as ‘data-driven learning’, DDL) for error resolution in L2 writing. However, a crucial yet underexplored variable in this process is whether and how the form of written corrective feedback (WCF) provided on L2 writing facilitates effective corpus consultation for L2 error resolution. Focusing on L2 writers at the post-graduate level and using a short private online course for DDL training, we determine the impact of four WCF conditions (varying in their degree of directness) on students’ use of corpora for lexical and grammatical error resolution, and the appropriacy of error revisions made with/without corpora for these error types. The results suggest that ‘less (WCF) is more’ if learners are to make successful error revisions via corpus consultation, with more direct WCF conditions often resulting in students revising errors without consulting a corpus. However, less direct WCF conditions sometimes resulted in inappropriate revisions, as learners required additional information as to the nature and location of the specific error. Differences were also found in the effectiveness of corpus consultation for grammatical and lexical error types, with WCF a confounding factor. These results suggest that if corpora are to be used for L2 error resolution, teachers need to carefully consider whether their WCF allows for meaningful engagement with corpora to occur, and whether corpus consultation is suitable or desirable for resolving all error types.

Improved performance of impulse active noise control using active function threshold with absolute harmonic variable step-size algorithm

The Standard (conventional) adaptive algorithms exhibits low convergence rate and minimum noise suppression, or else the system becomes unstable under Gaussian and non-Gaussian (impulsive noise SαS distributions) noise environments. In order to overcome the drawback of traditional algorithms (i.e., to eliminate unwanted noise), the popular algorithm Filtered Cross Minimum Square (FxLMS) is used in Active Noise Control (ANC), not only to improve its efficiency but also to improve its performance. In this paper, we proposed two improvements: first, we proposed a novel method Active threshold function FxLMS (ATFxLMS) being employed in ANC in the paths of primary (reference) and error signals; a second proposal is employing the Variable Step-Size based on Absolute Harmonic Mean (AHMVSS) of error signal. The idea behind this method is that the step-size of the algorithm varies depending on the harmonic mean of error signal obtained from the error location. In comparison to the fixed step-size algorithm, the proposed ATF-AHMVSS provided an improved convergence rate for the desired ANC efficiency. Moreover computational complication of the proposed method was examined as it was found that the proposed algorithm provided stable condition for ANC systems. Computer simulation results are revealed that the proposed (AT & AHMVSS-FxLMS) algorithm have attained excellent performance in terms of convergence speed, noise reduction and minimum steady state error as compared to other existing algorithms under different noise inputs. The results obtained from the proposed algorithm show outperformance compared to traditional adaptive algorithms.

Lower complexity error location detection block of adjacent error correcting decoder for SRAMs

Multiple cell upsets (MCUs) caused by radiation is an important issue related to the reliability of embedded static random access memories (SRAMs). Multiple random and adjacent error correcting codes have been extensively employed for several years to protect stored data in SRAMs against MCUs. A compact and fast error correcting codec is desirable in most of these applications. In this study, simplified expressions for error location detection (ELD) block for single error correction-double error detection-double adjacent error correction (SEC-DED-DAEC) and single error correction-double error detection-triple adjacent error correction (SEC-DED-TAEC) decoders have been obtained by employing Karnaugh map. The conventional SEC-DED-DAEC and SEC-DED-TAEC decoders have been designed and implemented in both field-programmable gate array and ASIC platforms by considering these simplified ELD expressions. In FPGA platform, the proposed design for SEC-DED-DAEC and SEC-DED-TAEC decoders require 1.37–28.40% improvement in area and maximum 14.74% improvement in delay compared to existing designs. Whereas ASIC-based designs provide 2.20–26.81% reduction in area and 0.30–28.96% reduction in delay compared to existing related works. So the proposed design can be considered as an efficient alternative of traditional adjacent error correcting decoders in resource constraint applications.

Issues in Interactive Translation Practice on Twitter

I used my Twitter account to tweet images of English and Arabic texts to be translated by my student followers who are translation major. My followers translated the texts and corrected the translation errors, tweeted and re-tweeted their translations and corrections for feedback. I gave feedback on the location and types of translation errors, tweeted prompts, translation tips and resources while followers were re-thinking and working on their answers. The followers reported that they benefited from the variety of translation tips, feedback and dictionaries tweeted. Further pedagogical issues, reflections and recommendations on interactive translation practice via Twitter are given.

HELP: a sparse error locator polynomial for BCH codes

In 1990 Cooper suggested to use Groebner bases’ computations to decode cyclic codes and his idea gave rise to many research papers. In particular, as proved by Sala-Orsini, once defined the polynomial ring whose variables are the syndromes, the locations and the error values and considered the syndrome ideal, only one polynomial of a lexicographical Groebner basis for such ideal is necessary to decode (the general error locator polynomial, a.k.a. GELP). The decoding procedure only consists in evaluating this polynomial in the syndromes and computing its roots: the roots are indeed the error locations. A possible bottleneck in this procedure may be the evaluation part, since a priori the GELP may be dense. In this paper, focusing on binary cyclic codes with length $$n=2^m-1$$, correcting up to two errors, we give a Groebner-free, sparse analog of the GELP, the half error locator polynomial (HELP). In particular, we show that it is not necessary to compute the whole Groebner basis for getting such kind of locator polynomial and we construct the HELP, studying the quotient algebra of the polynomial ring modulo the syndrome ideal by a combinatorial point of view. The HELP turns out to be computable with quadratic complexity and it has linear growth in the length n of the code: $${\mathcal {O}}\left( \frac{n+1}{2}\right)$$.

Analysis of mathematical creativity in mathematics learning is open ended

The ability of mathematical creativity is needed by every mathematics education student. Mathematical creativity is an important part of Mathematics education. But the mathematical creativity of most Mathematics Education students is still low. Therefore, mathematical creativity is needed for students in Mathematics Education, especially for students who are studying Real Analysis courses. Based on the results of the Open-Ended Real Analysis course, it can be seen the quality of the students’ mathematical creativity. The purpose of this study is to analyze the location, causes, and types of student errors in doing Open-Ended Real Analysis test questions through the use of the Newman Error Analysis (NEA) medium. Newman Error Analysis includes Reading Error, Comprehension Error, Error Transformation, Skill Error Process, and Encoding Error. This research is a type of qualitative research. The subjects of this study were students taking Real Analysis courses in the Mathematics Education Study Program at Pancasakti University, Tegal Indonesia. The research subjects were 64 students. The results showed that students in doing the Open-Ended Real Analysis test questions were still confused using the theorem that was right to use. It means that students in the transformation process discuss problems and the skill process is still lacking. This is by the five types of errors / Newman Error Analysis described by experts in Mathematics Education. The new findings in this study are errors of carelessness not working on problems, and misconceptions.

Design of GIS Intelligent Navigation Information Control System for Micro Air Vehicle

The traditional control system cannot determine the specific location of the transmission error of navigation information, the implementation process is complex, and the information sequence needs to be fed back to the source, resulting in reduced transmission efficiency and high delay of navigation information, so that the control effect is unsatisfactory. To this end, a GIS intelligent navigation information control system for micro air vehicle (MAV) is proposed. The BER calculation equation is designed and the principle of turbo encoder is analysed. The pseudo-random sequence is used to process the intelligent navigation information of the MAV to form an intelligent navigation information sequence. Without feedback to the source, the output information sequence can be dispersed due to the error code of sudden interference. Through the MAP method, the absolute value of the posterior probability ratio is regarded as the soft decision output, the code is used to obtain the error position and the transmission error of the intelligent navigation information is controlled, so that the design of the GIS intelligent navigation information control system for MAV is completed. The experimental results show that the improved system can better control the transmission error of navigation information, and the control effect is very satisfactory.

A Secure Architecture for Modular Division over a Prime Field against Fault Injection Attacks

Fault injection attacks pose a serious threat to many cryptographic devices. The security of most cryptographic devices hinges on a key block called modular division (MD) over a prime field. Although a lot of research has been done to implement the MD over a prime field in hardware efficiently, studies on secure architecture against fault injection attack are very few. A few of the studies that focused on secure architecture against fault injection attack can only detect faults but not locate faults. In this regard, this paper designs a novel secure architecture for the MD over a prime field, which can not only detect faults, but also can locate the error processing element. In order to seek the best optimal performance, four word-oriented systolic structures of a main function module (MFM) were designed, and three error detection schemes were developed based on different linear arithmetic codes (LACs). The MFM structures were combined flexibly with the error detection schemes. The time and area overheads of our architecture were analyzed through the implementation in an application-specific integrated circuit (ASIC), while the error detection and location capabilities of our architecture were demonstrated by C++ simulation, in comparison to two existing methods. The results show that our architecture can detect single-bit error (SBE) with 100% accuracy and locate the erroneous processing element (PE), and correctly identify most of the single PE errors and almost all of the multi-PE errors (when there are more than three erroneous PEs). The only weakness of our architecture is the relatively high time and area overhead ratios.

NucBreak: location of structural errors in a genome assembly by using paired-end Illumina reads

BackgroundAdvances in whole genome sequencing strategies have provided the opportunity for genomic and comparative genomic analysis of a vast variety of organisms. The analysis results are highly dependent on the quality of the genome assemblies used. Assessment of the assembly accuracy may significantly increase the reliability of the analysis results and is therefore of great importance.ResultsHere, we present a new tool called NucBreak aimed at localizing structural errors in assemblies, including insertions, deletions, duplications, inversions, and different inter- and intra-chromosomal rearrangements. The approach taken by existing alternative tools is based on analysing reads that do not map properly to the assembly, for instance discordantly mapped reads, soft-clipped reads and singletons. NucBreak uses an entirely different and unique method to localise the errors. It is based on analysing the alignments of reads that are properly mapped to an assembly and exploit information about the alternative read alignments. It does not annotate detected errors. We have compared NucBreak with other existing assembly accuracy assessment tools, namely Pilon, REAPR, and FRCbam as well as with several structural variant detection tools, including BreakDancer, Lumpy, and Wham, by using both simulated and real datasets.ConclusionsThe benchmarking results have shown that NucBreak in general predicts assembly errors of different types and sizes with relatively high sensitivity and with lower false discovery rate than the other tools. Such a balance between sensitivity and false discovery rate makes NucBreak a good alternative to the existing assembly accuracy assessment tools and SV detection tools. NucBreak is freely available at https://github.com/uio-bmi/NucBreak under the MPL license.

Comparison of the Iowa Reference Algorithm to the Heidelberg Spectralis optical coherence tomography segmentation algorithm.

For spectral-domain optical coherence tomography (SD-OCT) studies of neurodegeneration, it is important to understand how segmentation algorithms differ in retinal layer thickness measurements, segmentation error locations and the impact of manual correction. Using macular SD-OCT images of frontotemporal degeneration patients and controls, we compare the individual and aggregate retinal layer thickness measurements provided by two commonly used algorithms, the Iowa Reference Algorithm and Heidelberg Spectralis, with manual correction of significant segmentation errors. We demonstrate small differences of most retinal layer thickness measurements between these algorithms. Outer sectors of the Early Treatment Diabetic Retinopathy Study grid require a greater percent of eyes to be corrected than inner sectors of the retinal nerve fiber layer (RNFL). Manual corrections affect thickness measurements mildly, resulting in at most a 5% change in RNFL thickness. Our findings can inform researchers how to best use different segmentation algorithms when comparing retinal layer thicknesses.

Mode shape transformation for model error localization with modal strain energy

A modeling error location method based on modal strain energy is presented in this paper. Errors in the design model with shell elements are located by an error indicator which is based on changes between the equivalent modal strain energy and the modal strain energy of the design model. The equivalent modal strain energy is defined as a quadratic form using the stiffness matrix of the design model and the mode shape of the reference coming from the sophisticated and high fidelity finite-element model, called the supermodel, or the full-field measurement. The major obstacle to obtain the equivalent modal strain energy is how to match the mode shapes of a solid element and those of a shell element since each node of the solid element contains only three translation degrees of freedom (dofs) while each node of the shell element has six dofs, including three translation and three rotation components. In order to solve this problem, a mode shape transformation method from the solid element to the shell element is proposed using the shape functions or linear approximation. Using this approach, the errors in the design model can be determined and the updating parameters can be selected so that the updated model has physical meaning and can represent the dynamic characteristics of the real structure. The simulation of a simple plate is used initially to illustrate the effectiveness of the proposed method. Then, a rotor test rig casing is taken as an example for further investigation. A comparison of the updating parameters selected by the proposed method and the traditional sensitivity analysis technique is then undertaken. It is verified that the updating parameters selected based on error location have physical sense and represent the true errors in the design model through the updating results. The advantage of this technique is that only detailed mode shapes from the reference is required. The approach shows potential for further industrial engineering applications.

Tracking of unpredictable moving stimuli by pigeons

Despite being observed throughout the animal kingdom, catching a moving object is a complex task and little is known about the mechanisms that underlie this behavior in non-human animals. Three experiments examined the role of prediction in capture of a moving object by pigeons. In Experiment 1, a stimulus moved in a linear trajectory, but sometimes made an unexpected 90o turn. The sudden turn had only a modest effect on capture and error location, and the analyses suggested that the birds had adjusted their tracking to the novel motion. In Experiment 2, the role of visual input during a turn was tested by inserting disappearances (either 1.5 cm or 4.5 cm) on both the straight and turn trials. The addition of the disappearance had little effect on capture success, but delayed capture location with the larger disappearance leading to greater delay. Error analyses indicated that the birds adapted to the post-turn, post-disappearance motion. Experiment 3 tested the role of visual input when the motion disappeared behind an occluder and emerged in either a straight line or at a 90o angle. The occluder produced a disruption in capture success but did not delay capture. Error analyses indicated that the birds did not adjust their tracking to the new motion on turn trials following occlusion. The combined results indicate that pigeons can anticipate the future position of a stimulus, and can adapt to sudden, unpredictable changes in motion but do so better after a disappearance than after an occlusion.

Decoding algorithm as a moment problem related to the extended Lotka–Volterra system

The moment problem related to the extended Lotka–Volterra system (sometimes also called the hungry Lotka–Volterra system or the Narita–Itoh–Bogoyavlensky lattice) over finite fields is introduced. It turns out the moment problem could be used to design an algorithm for decoding multiple BCH-Goppa codes over the same finite field simultaneously. When multiple codes have the same error locations, the algorithm requires fewer known syndromes and has lower computational complexity than running the decoding algorithm in Nakamura (1996 Phys. Lett. A 223 75–81) multiple times.

PVcon: Localizing Hidden Concurrency Errors With Prediction and Verification

Multi-core techniques have been widely used in various hardware platforms, promoting development of concurrent programs. Unfortunately, concurrent programs are prone to concurrency errors. At present, it is still an open issue to provide high coverage detection of concurrency errors. In this paper, we present an enhanced dynamic concurrency error detection technique, called PVcon, which can detect more concurrency errors than existing techniques. PVcon first finds suspicious locations of concurrency errors by applying a novel relation, elastic-causalities (EC), and then strictly verifies each suspicious concurrency errors with a lightweight intentional scheduling technique. We have implemented PVcon in C/C++ and evaluated it by localizing concurrency errors from real-world programs. The experimental results show that PVcon can efficiently detect twice more concurrency errors than other techniques.

On method of composing low frequency signals based on array structures

Generating low-frequency electromagnetic waves based on high-frequency antenna and illuminating targets with multi-band signals can be an effect way that can not only reduce the physical dimension of a low frequency antenna, but also improve the performance of radar detection. Combining the electromagnetic wave doppler effect principle and the array antenna architecture, a method of generating a low-frequency signal around the illuminated target is proposed based on the controlling of array antenna parameters, including array radiation element signal timing, phase and element spacing. The principles of array parameter design are described. Composite signals are simulated respectively under two typical geometric relationships between targets and array antenna, target located along the array direction and in the direction of 45° scanning angle. The peak sidelobe ratio (PSLR) and integral sidelobe ratio (ISLR) are used to evaluate the quality of the composite signals. Aiming at practical applications, the effects of array element spacing error, phase error and target location error on the composite signal are simulated and analyzed. Under the condition of sparse uniform array, the influence of the radiation element spacing on the composite signal is analyzed. The simulation results show that the harmonic components of the composite signal increase with the radiating element spacing error and phase error growing.

High-Threshold Code for Modular Hardware With Asymmetric Noise

We consider an approach to fault tolerant quantum computing based on a simple error detecting code operating as the substrate for a conventional surface code. We develop a customised decoder to process the information about the likely location of errors, obtained from the error detect stage, with an advanced variant of the minimum weight perfect matching algorithm. A threshold gate-level error rate of 1.42% is found for the concatenated code given highly asymmetric noise. This is superior to the standard surface code and remains so as we introduce a significant component of depolarising noise; specifically, until the latter is 70% the strength of the former. Moreover, given the asymmetric noise case, the threshold rises to 6.24% if we additionally assume that local operations have 20 times higher fidelity than long range gates. Thus for systems that are both modular and prone to asymmetric noise our code structure can be very advantageous.

Jackknife method for the location of gross errors in weighted total least squares

Because the weighted total least squares (WTLS) method lacks robustness and is sensitive to gross errors, it cannot eliminate the influence of outliers effectively. A small number of gross errors may produce a devastating effect on estimates. Focusing on the limitation of the WTLS method regarding the influence of gross errors, this work combines Jackknife resampling theory with the WTLS algorithm for the identification and detection of outliers. The gross errors located in the WTLS method by the Jackknife method are identified to further improve the qualities of the estimated values if the observation data are falsified by outliers. This paper focuses on the following two aspects: only one gross error and multiple gross errors. Detailed calculation steps and the whole procedure for outlier detection using the new method are given. This algorithm is applied to the straight-line fitting model and the plane coordinate transformation model. From the experimental estimation results, we can see that the method proposed in this paper can identify gross errors that are greater than or equal to three times the standard error, and obtain more accurate estimation values when compared with the WTLS method and the classic robust weighted total least squares (RWTLS) method. The numerical case studies verify the effectiveness and practicality of the proposed procedure.

Validation Method for Simulation Model of Internet of Things-Aided Power System

Validation of power system simulation models is essentially a similarity analysis problem based on multivariate time series. With the development of the internet of things (IoT) technology in the power system, the interoperability and integration of devices in the practical project are improved, and the cross interaction in the simulation process becomes more complex correspondingly. It is critical to explore the inherent correlation from the high dimensional data to evaluate the credibility and to locate the error of the simulation model. Thus, a model validation method based on factor analysis and the Prony method is proposed in this paper. Firstly, the multivariate time series of the simulation model and the practical/acknowledged system are replaced by a low number of common factors with physical meanings by factor analysis. Secondly, the modified adaptive Prony method is applied to extract the features of each common factor to ensure the best fitting of the non-stationary signal. Then the complete similarity evaluation model of the simulation system is established based on energy proportion, information entropy, and variance of the contribution rate. Finally, the error location is identified in the evaluation process based on the physical meaning of extracted features. The feasibility and effectiveness of the proposed method are verified by an application in the simulation model of a power electronics system developed in PSASP.

Analisis Kesalahan Fonologis Membaca Teks Bahasa Arab Siswa Madrasah Tsanawiyah Lampung Selatan

This study aims to find and reduce the location of errors in learning Arabic in the aspect of reciting Arabic letters (makhorijul letters) with the error analysis method. Focus more specifically on the phonetic aspect, namely on letters that sound like sounds. In addition, this study also aims to determine the forms of errors in reading Arabic texts in the phonological level (phonetic / makhroj aspects). This type of research is a qualitative study, conducted at MTs. Raudlatul Jannah Natar, South Lampung. Understanding the study of how to pronounce or sound Arabic letters is very important in learning Arabic to avoid pronunciation errors, so it does not hamper the learning process. The results of this study indicate that the forms of phonological errors that often occur when reading Arabic text activities are errors in sound in terms of articulation factors including among them: 1) apico-dental-alveolar sound. 2) Inter-dental sound. 3) Foronto-palatal sounds. 4) Dorso-uvular sound. 5) Dorso-velar sound. 6) Sound of avico-alveolars. 7) The sound of root-pharyngeals. The sound error in terms of aspects of articulation that is in: 1) fricative sound. 2) pop sound.