“连接学习”:美国青少年数字阅读推广的关联与创新策略

近年,在"连接学习"理论的支持下,美国面向青少年开展了大量基于"连接学习"的数字阅读推广项目,其中"你的媒体"(Youmedia)、"探索学习"(Quest to Learn,简称Q2L)等项目已经取得了一定的推广效果,在美国多个州立学校和公共图书馆得到推广。基于"连接学习"的数字阅读推广项目采取"兴趣驱动"的设计,为青少年塑造同辈文化环境和明确的学术目标,以青少年数字内容创作和生产能力培养为重点,着力为数字时代"创造性人才"培养服务,对于我国创新创业人才培养和数字阅读推广项目的设计和开展具有一定的启发意义。

Dynamic batch selective sampling based on version space analysis

A novel dynamic batch selective sampling algorithm based on version space analysis is presented. In the traditional batch selective sampling, example selection is entirely determined by the existing unreliable classification boundary; meanwhile, within a batch, examples labeled previously fail to provide instructive information for the selection of the rest. As a result, using the examples selected in batch mode for model refinement will jeopardize the classification performance. Based on the duality between feature space and parameter space under the SVM active learning fi：amework, dynamic batch selective sampling is proposed to address the problem. We select a batch of examples dynamically, using the examples labeled previously as guidance for further selection. In this way, the selection of feedback examples is determined by both the existing classification model and the examples labeled previously. Encouraging experimental results demonstrate the effectiveness of the proposed algorithm.

Integration of Computer Assisted Learning in Teaching and Learning in Secondary Schools in Kenya

The purpose of this study was to establish factors that lead to poor integration of Information and communication technology （ICT） for teaching and learning in schools in Kenya, despite comprehensive policy, institutional, infrastructural frameworks and capacity building by the Ministry of Education. The subject of this study was administered by use of questionnaires in three categories of public schools： national school, provincial schools and district schools. The respondents were students from each level that is from one, two, three and four and teachers based on the most offered subjects in the secondary schools. The computer assisted learning facilities were classified into computers, internet and content in optical media. In national school Internet based research, optical media content provided by Kenya Institute of Curriculum Development and Cyber School program for science subjects was used in learning. In provincial school, it lacks adequate computers, reliable Internet and content in optical media. In district school, it lacks adequate computer, no internet connection and content in optical media. A learner management system which can be accessed by all learners by use of any internet access devices like mobile phone access will be an ideal tool with over 4,000,000 mobile phone subscribers currently in Kenya.

A Corpus-Based Study of Adverbial Connectors in Native and Non-native Students＇ Writing

In writing and speaking, adverbial connectors always play a part to connect different parts together at both semantic and syntactic aspects. For it is so important that a lot of scholars have made and are making a series of studies to their functions. On the basis of corpus-based study, this paper firstly makes a comparison to the usage of adverbial connectors in their writings of the native students and non-native students and then exposes a distinctive gap between these two types of writings in usage of adverbial connectors. In order to help Chinese second-language learners acquire English as well as English native speakers do, this study deeply digs this gap and in further provides several pedagogical suggestions for English teachers and second-language learners.

Extending self-organizing maps for supervised classification of remotely sensed data

An extended self-organizing map for supervised classification is proposed in this paper. Unlike other traditional SOMs, the model has an input layer, a Kohonen layer, and an output layer. The number of neurons in the input layer depends on the dimensionality of input patterns. The number of neurons in the output layer equals the number of the desired classes. The number of neurons in the Kohonen layer may be a few to several thousands, which depends on the complexity of classification problems and the classification precision. Each training sample is expressed by a pair of vectors ： an input vector and a class codebook vector. When a training sample is input into the model, Kohonen＇s competitive learning rule is applied to selecting the winning neuron from the Kohouen layer and the weight coefficients connecting all the neurons in the input layer with both the winning neuron and its neighbors in the Kohonen layer are modified to be closer to the input vector, and those connecting all the neurons around the winning neuron within a certain diameter in the Kohonen layer with all the neurons in the output layer are adjusted to be closer to the class codebook vector. If the number of training sam- ples is sufficiently large and the learning epochs iterate enough times, the model will be able to serve as a supervised classifier. The model has been tentatively applied to the supervised classification of multispectral remotely sensed data. The author compared the performances of the extended SOM and BPN in remotely sensed data classification. The investigation manifests that the extended SOM is feasible for supervised classification.

On Application of Computer-based Corpora in Translation

Authors of papers to proceedings have to type these in a form suitable for direct photographic reproduction bthrough the research methods about analyzing computer corpus translation and inter-language research methods, and through comparison analysis about three of more thaxL four hundred thousand words, link adverbs in Chinese and English corpus and its corresponding Chinese word retrieval results, and make a detailed description of the characteristic for Chinese English learners and native English speakers, and thus provides an application example to study corpus in translation.

Studying Language Learners＇ Cognition： Perspectives in L2 Teaching

This paper investigates one aspect of the processing perspective in L2 （the second language） learning： the processing of new words. The article does not try to offer a comprehensive overview of language acquisition mechanisms, but rather it intends to review more narrowly how our conceptual systems, governed by intricately linked networks of neural connections in the brain, make language development possible, at the same time creating some L2 processing problems. Vocabulary acquisition and application has been one of the main issues in English as a Second Language （ESL）/English as a Foreign Language （EFL） learning and teaching research. EFL instructors in Bosnia and Herzegovina, in particular, are coping with the effective vocabulary teaching approaches. The current paper will examine three principles based on cognitive linguistics （CL）, namely the study of categorization, prototype, and metaphor, and applications of these principles in formal vocabulary instruction in a Bosnian context of English learning in Bosnia and Herzegovina.

THE EFFECT OF THE USE OF ADVERBIAL CONNECTORS ON CHINESE EFL LEARNERS' ENGLISH WRITING QUALITY

This paper reports a corpus-based study on the use of adverbial connectors by Chinese non-English major EFL learners with different English proficiency levels. Research results show that there is a significant correlation between the learners' use of adverbial connectors and their writing quality. The Chinese learners with higher linguistic proficiency use more tokens and types of adverbial connectors and perform better in the use of adverbial connectors in terms of stylistic awareness in their writings than those with lower linguistic proficiency.

Investigation of the association between all-trans-retinol dehydrogenase (RDH8) polymorphisms and high myopia in Chinese

Retinoic acid level in the retina/choroid is altered in induced myopia models.All-trans-retinol dehydrogenase(RDH8) is an important enzyme of retinoic acid metabolism.This study aimed to investigate the association of the RDH8 gene with high myopia.Three single nucleotide polymorphisms(SNPs) [RDH851(rs2233789) ,RDH8E5a(rs1644731) ,and RDH855b(rs3760753) ]were selected,based on the linkage disequilibrium pattern of RDH8 from a previous study,and genotyped for 160 Han Chinese nuclear families with highly myopic(-10 diopters or worse) offspring as well as in an independent group with 166 highly myopic cases(-10 diopters or worse) and 211 controls. Family-based association analysis was performed using the family-based association test(FBAT) package,and genotype relative risk(GRR) was calculated using the GenAssoc program.Population-based association analysis was performed using Chi-square test.These SNPs were in linkage equilibrium with each other.SNPs RDH851(rs2233789) and RDH8E5a(rs1644731) both did not show association with high myopia.SNP RDH855b(rs3760753) demonstrated significant association(P=0.0269) with a GRR of 0.543(95%confidence interval=0.304-0.968,P=0.038) .The association became statistically insignificant,however,after multiple comparison correction.Haplotype analysis did not show a significant association either.Population-based association analysis also showed no significant association(P>0.05) .Our family-and population-based data both suggest that the RDH8 gene is unlikely to be associated with high myopia in Chinese.

Coronarenes: recent advances and perspectives on macrocyclic and supramolecular chemistry

Synthetic macrocyclic host molecules always play an essential role in the establishment and development of supramolecular chemistry. Along with the continuous interests in the study of classical macrocycles, recent decades have witnessed the emergence and rapid development of the chemistry and supramolecular chemistry of novel and functional macrocycles. Owing to their easy availability, a self-tunable V-shaped cavity resulted from 1,3-alternate conformation, and diversified electronic features steered by the interplay between heteroatom linkages and aromatic rings, heteracalixaromatics act as a type of versatile and powerful macrocyclic hosts in molecular recognition and fabrication of supramolecular systems. Very recently, by means of engineering the bond connectivity or the recombination of chemical bonds within heteracalixaromatics, we have devised coronarenes, a new generation of macrocycles. In this concise review, macrocyclic and supramolecular chemistry of coronarenes are summarized in the order of their syntheses, structural features, molecular recognition and self-assembly properties. In the last part of this article, personal perspectives on the study of macrocyclic and supramolecular chemistry will also be discussed.