I/O端口地址译码技术

本文论述了接口和端口的联系与区别，I／O端口地址译码的重要性和一般原则，以丰富的实例详细阐述了I／O端口地址译码的电路设计技术。     

The beginning of decoding

It is widely agreed that children recognize their first words in a different way than they later decode. One hypothesis is that sight words are recognized as wholes, another that they are recognized by parts. Two experiments were devised to compare these hypotheses. In one, children were taught a sight word accompanied by a salient extraneous cue and then tested for recognition of the word and the cue. In the other, children were taught sight words, then tested for recognition of each half of the word. The children were found to recognize the cue but not the word; they recognized one half of the word but not the other. The results support the idea that first words are recognized by selective association.     

Context-sensitive regularities in English vowel spelling

The predictive value of rime spellings in English was compared directly to other types of regularities beyond the level of the single letter. A computer-assisted analysis of a list of twenty-four thousand written words, each paired with its corresponding pronunciation, reveals that only a small number of rime spellings are highly regular in their pronunciations. The conventional division of vowel letter pronunciations into short and long in closed and open written syllables is the most reliable key to English pronunciation. Our findings support the notion that English spelling is based at least in part on syllable structure. In addition, prefixes and suffixes provide very reliable clues to pronunciation, which suggests that their regularity should be exploited in the teaching of reading.     

Toward a set of design principles for decoding training: A systematic review of studies of English as a foreign/second language listening education

Listening is a major challenge for many English as a foreign language (EFL)/English as a second language (ESL) learners. Many learners find it difficult to immediately process and segment an ongoing stream of sounds. Decoding training is one of interventions that have been used to assist EFL/ESL learners. This paper reviewed empirical studies of the effectiveness of decoding training in developing EFL/ESL learners' listening. We examined the following four major factors: (a) the types of instructional activities used; (b) the effects of decoding training on student listening outcomes; (c) the main instructional enablers of decoding training; and (d) the main instructional barriers to decoding training. The two activities most frequently used for decoding training were dictation and pronunciation instruction. A meta-analysis of 13 intervention studies showed an overall significant effect in favor of decoding training over non-decoding instruction for listening education (Hedges's g = 0.553, CI = 0.348–0.759, 95% confidence interval, p = 0.000), with no evidence of publication bias. Two theoretical frameworks, cognitive learning theory and the attention, relevance, confidence, and satisfaction model, were used to synthesize 33 studies to analyze the common elements that promote and hinder the development of learners' decoding skills. We proposed a set of design principles for decoding training that are expected to enhance the effectiveness and efficiency of decoding training in EFL/ESL listening education.     

Listening comprehension and reading comprehension in poor decoders: Evidence for the importance of syntactic and semantic skills as well as phonological skills

The relation between decoding and comprehensionin the oral and written modalities was studiedin a randomly selected group of nine-year-olds,subdivided into good, average and poordecoders. Performances on two types ofcomprehension tasks (story retelling andcloze tasks) were compared and related tophonological, syntactic and semantic abilities.(Story retelling demanded the ability to retellthe gist of a story, while the cloze tasksdemanded precise skills in drawing anaphoricreference across sentence boundaries.) Atwo-way analysis of variance using IQ ascovariate showed that poor decoders scoredlower than average and good decoders on allcomprehension tasks. This suggests a highdegree of interdependence between listeningcomprehension, reading comprehension anddecoding. The associated pattern of oralcorrelates furthermore varied with task demandsand to some extent, independent of modality.Vocabulary was related to the ability toretell a story. Syntax and, in particularphonemic awareness, were on the otherhand more strongly related to the ability todraw anaphoric reference. The results wereinterpreted in favor of ``the phonologicaldeficit hypothesis', but the interactionbetween linguistic sub-skills and task demandswas also underscored.     

空间型字典压缩编码

用Object Pascal语言实现LZW压缩方法,用面向对象方法进行封装,并在其编码算法上做了改进,实现了零搜索,大大加快了编码速度。     

Reading and spelling difficulties in high school students: Causes and consequences

Basic skills in reading and spelling and supporting metalinguistic abilities were assessed in ninth and tenth grade students in two school settings. Students attending a private high school for the learning disabled comprised one group and the other comprised low to middle range students from a public high school. Both the LD students and the regular high school students displayed deficiencies in spelling and in decoding, a factor in reading difficulty that is commonly supposed to dwindle in importance after the elementary school years. Treating the overlapping groups as a single sample, multiple regression analysis was used to investigate the contribution of nonword decoding skill and phonological and morphological awareness to spelling ability. The analysis revealed that decoding was the major component, predicting about half of the variance in spelling. The effect of phonological awareness was largely hidden by its high correlation with decoding, but was a significant predictor of spelling in its own right. Morphological awareness predicted spelling skill when the words to be spelled were morphologically complex. An additional study showed that differences in decoding and spelling ability were associated with differences in comprehension after controlling for reading experience and vocabulary. Even among experienced readers individual differences in comprehension of text reflect efficiency of phonological processing at the word level.     

Phonological skills and reading comprehension

In the present study the mainfocus is on the impact of phonologicalawareness on reading comprehension. The studyinvolved 1300 children in Grade 1. Syllableawareness, phoneme awareness, word decodingand reading comprehension were each assessedwith two or three subtests. The results wereanalyzed by structural modeling. Due to themarked skewness observed for some of themanifest variables, separate analyses wereperformed for students with average worddecoding performance and for students with poorword decoding. Both among average and poordecoders, phonological awareness had a directimpact on reading comprehension, indicatingthat phonological factors play an independentrole in the processing of text. One possibleway to explain this observation is that atleast two critical factors in comprehension,vocabulary and short-term memory, are bothdetermined in part by phonological ability. Itmight also be the case that phonologicalawareness partly reflects metacognitiveprocesses assumed to be involved in readingcomprehension.     

Explaining social class differences in growth of reading skills from beginning kindergarten through fourth-grade: The role of phonological awareness,rate of access,and print knowledge

The aim of this longitudinal study was to further ourunderstanding of the reasons for social classdifferences in growth of decoding and readingcomprehension skills from beginning kindergarten throughchildren's fourth grade year. Participants wereenrolled in five public schools in a moderately sizedsouthern American city (n = 197). We examined ifbeginning kindergarten levels of three kinds ofreading related abilities explained social classdifferences in growth of reading skills during thetime periods of beginning kindergarten to children'sfirst-, second-, third-, and fourth-grade years. Thereading related abilities were phonological awareness,rate of access to phonological information inlong-term memory, and print knowledge. We found thatthe reasons for social class differences in growth ofreading skills depended on the time interval that wasconsidered. During the earliest time interval, socialclass differences in growth of decoding skills werecompletely accounted for by performance on the controlmeasures of general verbal intelligence and prior wordreading skills. During the remaining time periods,social class differences in growth of decoding andreading comprehension skills persisted whenperformance on the three kinds of reading relatedabilities and the control measures were accounted for. The greatest attenuation of SES differences in growthof reading skills occurred when beginning kindergartenlevels of print knowledge were taken into account.     

Solving graphics tasks: Gender differences in middle-school students

The capacity to solve tasks that contain high concentrations of visual-spatial information, including graphs, maps and diagrams, is becoming increasingly important in educational contexts as well as everyday life. This research examined gender differences in the performance of students solving graphics tasks from the Graphical Languages in Mathematics (GLIM) instrument that included number lines, graphs, maps and diagrams. The participants were 317 Australian students (169 males and 148 females) aged 9-12 years. Boys outperformed girls on graphical languages that required the interpretation of information represented on an axis and graphical languages that required movement between two- and three-dimensional representations (generally Map language).