746 research outputs found
On the probability of undetected error for the maximum distance separable codes
The performance of maximum-distance-separable codes with symbols from GF(1) when they are used for pure error detection or for simultaneous error correction and detection is investigated. These codes are good for symbol error detection. Their probability of undetected error is upper bounded by q to the -r and decreases monotonically as the symbol error probability epsilon decreases from (q-1)/q to 0, where r is the number of parity-check symbols of a code
A concatenated coded modulation scheme for error control
A concatenated coded modulation scheme for error control in data communications is presented. The scheme is achieved by concatenating a Reed-Solomon outer code and a bandwidth efficient block inner code for M-ary PSK modulation. Error performance of the scheme is analyzed for an AWGN channel. It is shown that extremely high reliability can be attained by using a simple M-ary PSK modulation inner code and relatively powerful Reed-Solomon outer code. Furthermore, if an inner code of high effective rate is used, the bandwidth expansion required by the scheme due to coding will be greatly reduced. The proposed scheme is particularly effective for high speed satellite communication for large file transfer where high reliability is required. Also presented is a simple method for constructing block codes for M-ary PSK modulation. Some short M-ary PSK codes with good minimum squared Euclidean distance are constructed. These codes have trellis structure and hence can be decoded with a soft decision Viterbi decoding algorithm
Suboptimum decoding of block codes
This paper investigates a class of decomposable codes, their distance and structural properties. it is shown that this class includes several classes of well known and efficient codes as subclasses. Several methods for constructing decomposable codes or decomposing codes are presented. A two-stage soft decision decoding scheme for decomposable codes, their translates or unions of translates is devised. This two-stage soft-decision decoding is suboptimum, and provides an excellent trade-off between the error performance and decoding complexity for codes of moderate and long block length
A cascaded coding scheme for error control
A cascade coding scheme for error control is investigated. The scheme employs a combination of hard and soft decisions in decoding. Error performance is analyzed. If the inner and outer codes are chosen properly, extremely high reliability can be attained even for a high channel bit-error-rate. Some example schemes are evaluated. They seem to be quite suitable for satellite down-link error control
Multi-stage decoding for multi-level block modulation codes
Various types of multistage decoding for multilevel block modulation codes, in which the decoding of a component code at each stage can be either soft decision or hard decision, maximum likelihood or bounded distance are discussed. Error performance for codes is analyzed for a memoryless additive channel based on various types of multi-stage decoding, and upper bounds on the probability of an incorrect decoding are derived. It was found that, if component codes of a multi-level modulation code and types of decoding at various stages are chosen properly, high spectral efficiency and large coding gain can be achieved with reduced decoding complexity. It was found that the difference in performance between the suboptimum multi-stage soft decision maximum likelihood decoding of a modulation code and the single stage optimum decoding of the overall code is very small, only a fraction of dB loss in SNR at the probability of an incorrect decoding for a block of 10(exp -6). Multi-stage decoding of multi-level modulation codes really offers a way to achieve the best of three worlds, bandwidth efficiency, coding gain, and decoding complexity
Two hybrid ARQ error control schemes for near earth satellite communications
Two hybrid automatic repeat request (ARQ) error control schemes are proposed for NASA near earth satellite communications. Both schemes are adaptive in nature, and employ cascaded codes to achieve both high reliability and throughput efficiency for high data rate file transfer
Can digital storytelling enhance learning motivation for EFL students with low proficiency and confidence in English?
[EN] The purpose of this study was to investigate the impact of a digital storytelling assignment on English learning motivation of non-English major students with low proficiency and confidence in English in Japan.  The participants of this study were non-English major students in Japan who studied in four courses of English as a Foreign Language (EFL).  Each course was 15 weeks long and was held in the spring and fall terms of 2018. The study goal of the course was to acquire skills and knowledge to present ideas and messages effectively with the use of information communications and technology (ICT) and English. Three (pre-, midterm- and post-) questionnaires were employed to collect the necessary data. The results of the three questionnaires and two tests were received from 65 students.  This research focused on 27 students with low proficiency and confidence in English as determined by the results of the pre-questionnaire and pre-test. The analysis of the data showed that the digital storytelling assignment could enhance learning motivation for most participants with low proficiency and confidence in English. Most students with low proficiency and confidence in English in this course also felt confident about conducting a digital storytelling assignment in English. I would like to thank Dr Julian Lewis for his advice on my paper.Kasami, N. (2021). Can digital storytelling enhance learning motivation for EFL students with low proficiency and confidence in English?. The EuroCALL Review. 29(1):68-80. https://doi.org/10.4995/eurocall.2021.12754OJS6880291Abdel-hack, E. M., & Helwa, A. A. (2014). Using digital storytelling and weblogs instruction to enhance EFL narrative writing and critical thinking skills among EFL majors at faculty of education. International Research Journal, 5(1): 8-41.Baturay, M., Daloglu, A. & Yildirim, S. (2010). Language practice with multimedia supported web-based grammar revision material. ReCALL, 22(3): 313-331. https://doi.org/10.1017/S0958344010000182Castañeda, M. E. (2013). "I am proud that I did it and it's a piece of me": Digital storytelling in the foreign language classroom, CALICO Journal, 30(1): 44-62. https://doi.org/10.11139/cj.30.1.44-62Chang, M. M., & Lehman, J. D. (2002). Learning foreign language through an interactive multimedia program: An experimental study on the effects of the relevance component of the ARCS model. CALICO Journal, 20(1): 81-89. https://doi.org/10.1558/cj.v20i1.81-98Dörnyei, Z. (2001). Teaching and Researching Motivation. Harlow: Pearson Education Limited.Dörnyei, Z. (2005). The psychology of the language learner: Individual differences in second language acquisition. London: Lawrence Erlbaum Associates Publishers.Dörnyei, Z. (2007). Creating a motivating classroom environment. In Cummins, J. & Davison, C. (Eds.), International handbook of English language teaching, 2, New York: Springer, 719-731. https://doi.org/10.1007/978-0-387-46301-8_47Kasami, N. (2014). The impacts of a digital storytelling assignment on non-English-major students' motivation for learning English in a Japanese university. In L. Liu & D. Gibson (Eds), Research highlights in technology and teacher education. Waynesville: Association for the Advancement of Computing in Education (AACE), 91-100.Kasami, N. (2017). The comparison of the impact of storytelling and digital storytelling assignments on students' motivations for learning. Proceedings of the EUROCALL 2017 Conference. CALL in a climate of change: adapting to turbulent global conditions. University of Southampton, 23-26 August. Research-publishing.net, https://doi.org/10.14705/rpnet.2017.eurocall2017.709Keller, J.M. (1983). Motivational design of instruction. In C. M. Reigeluth (ed.), Instructional design theories and models: An overview of their current status, Hillsdale, NJ: Lawrence Erlbaum Associates, 383-434.Keller, J. M. (1987). Development and use of the ARCS model of instructional design. Journal of Instructional Development, 10(3): 2-10.Keller, J. M. (2010). Motivational design for learning and performance: The ARCS model approach. New York: Springer. https://doi.org/10.1007/978-1-4419-1250-3Kikuchi, K. (2013). Demotivators in the Japanese EFL context. In Apple, M. T., Silva, D. D. & Fellner, T. (eds.), Language Learning Motivation in Japan, Bristol: Multilingual Matters, 206-224. https://doi.org/10.21832/9781783090518-014Liu, C. C., Wang, P. C. & Tai, S. J. D. (2016). An analysis of student engagement patterns in language learning facilitated by Web 2.0 technologies. ReCALL, 28(2): 104-122. https://doi.org/10.1017/S095834401600001XMacaro, E., Handley, Z. & Walter, C. (2012). A systematic review of CALL in English as a second language: Focus on primary and secondary education. Language Teaching, 45(1): 1-43. https://doi.org/10.1017/S0261444811000395Morizumi, M. (2019). The opening article, "Eigo no Jugyo de kotoba heno kiduki wo" [English language lessons for developing language awareness], The new English classroom 598, Tokyo: New English Teachers' Association. (in Japanese)Ohler, J. B. (2013). Digital storytelling in the classroom: New media pathways to literacy, learning, and creativity. Corwin Press. https://doi.org/10.4135/9781452277479Oskoz, A. & Elola, I. (2016). Digital stories: Bringing multimodal texts to the Spanish writing classroom. ReCALL, 28(3): 326-342. https://doi.org/10.1017/S0958344016000094Ribeiro, S. (2015). Digital storytelling: An integrated approach to language for the 21st century student. Teaching English with Technology, 15(2): 39-53.Robin, B. (2006). The Educational Uses of Digital Storytelling. Proceedings of SITE 2006, 709-716. Orlando, Florida: Association for the Advancement of Computing in Education (AACE).Song, S. H. & Keller, J. M. (2001). Effectiveness of motivationally adaptive computer-assisted instruction on the dynamic aspects of motivation. Educational Technology, Research and Development, 49(2): 5-22. https://doi.org/10.1007/BF02504925StoryCenter Website, Digital Storytelling for Educators. https://www.storycenter.org/public-workshops/edu-intro-to-ds (Last accessed: January 22, 2021)Suzuki, K., Nishibuchi, A., Yamamoto, M., & Keller, J. M. (2004). Development and evaluation of website to check instructional design based on the ARCS motivation model. Information and Systems in Education, 2(1): 63-69
Constructions of Generalized Concatenated Codes and Their Trellis-Based Decoding Complexity
In this correspondence, constructions of generalized concatenated (GC) codes with good rates and distances are presented. Some of the proposed GC codes have simpler trellis omplexity than Euclidean geometry (EG), Reed–Muller (RM), or Bose–Chaudhuri–Hocquenghem (BCH) codes of approximately the same rates and minimum distances, and in addition can be decoded with trellis-based multistage decoding up to their minimum distances. Several codes of the same length, dimension, and minimum distance as the best linear codes known are constructed
A cascaded coding scheme for error control and its performance analysis
A coding scheme is investigated for error control in data communication systems. The scheme is obtained by cascading two error correcting codes, called the inner and outer codes. The error performance of the scheme is analyzed for a binary symmetric channel with bit error rate epsilon <1/2. It is shown that if the inner and outer codes are chosen properly, extremely high reliability can be attained even for a high channel bit error rate. Various specific example schemes with inner codes ranging form high rates to very low rates and Reed-Solomon codes as inner codes are considered, and their error probabilities are evaluated. They all provide extremely high reliability even for very high bit error rates. Several example schemes are being considered by NASA for satellite and spacecraft down link error control
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