Recent advances in dust collection technology and ISO standardization in bag filtration

Dust collection technology is used not only as a countermeasure for air pollution, but also as removing technology for nano-particles, simultaneous removal of gas and dust, and facilitating the use of equipment in extreme conditions such as high and low pressures and temperatures. Particle concentration in the atmosphere, especially PM_2.5, has not decreased despite a reduction in the concentration of dust discharged from stationary sources. This is thought to be because of the formation of secondary particles following the discharge of condensable and/or reactive gaseous materials. Therefore, there needs to be an improvement in dust collection technology. In this paper, recent developments in dust collection technology, especially bag filtration and electrostatic precipitators, are described, and the ISO standards related to bag filtration are summarized. The future prospects for these technologies are outlined. This paper contributes to our understanding of the capture of particulate matter, which will support the improvement of particle removal technologies and the development of future applications.     

Social network analysis of international student mobility: uncovering the rise of regional hubs

Research on the patterns of international student mobility and the dynamics shaping these patterns has been dominated by studies reflecting a Western orientation, discourse, and understanding. Considering political, economic, cultural, historical, and ecological factors, this study argues that international student mobility is not only an issue of the economically developed, politically stable, and academically advanced Western world but also one that involves countries with different economic, political, and academic characteristics. Taking into account various theoretical orientations, this study argues that political, economic, cultural, and historical factors have led to the emergence of non-traditional destinations for international students; these countries are labeled as emergent regional hubs. In order to empirically test this, a social network analysis was conducted on a worldwide dataset representing 229 countries. The findings evidenced the strong position of traditional destinations for international students. However, the results also suggest the rise of several regional hubs, which are undergoing internationalization processes in different forms and with different rationales. The mobility patterns in emerging regional hubs deviate from those in traditional destinations, which fundamentally change the nature of internationalization in this context.     

The expositive discourse as pedagogical discourse: studying recontextualization in the production of a science museum exhibition

In this paper I report on the sociological and educational particulars of The Biodiscovery Space exhibition of the Life Museum of the Oswaldo Cruz Foundation in Rio de Janeiro, Brazil, using Basil Bernstein’s framework of pedagogic discourse and recontextualization. Data for analysis was obtained from interviews with the exhibition developers, field observations of museum visitors and analysis of exhibition documents. Using the ideas of power, classification and framework, among others, I analyzed the recontextualization process of the production of expositive discourse. Thus, working with Bernstein’s idea of classification, I explain the relationship between the discourses of the science of biology, history of science, museology, education, and communication in order to produce an expositive discourse. I also make explicit how agents of the Official Recontextualization Field of the Museum and the Pedagogic Recontextualization Field “....of the Museum determine partly the final expositive discourse of an exhibition”. Using the idea of a pedagogic discourse framework, I discuss how the constraints imposed by objects and texts in exhibitions help to create a specific manner of visitor interaction with these elements, “even if they have some autonomy”. Considerations about the audience and the intended process of acquisition are presented, when I discuss the control strategies of the exhibition. I propose that the Biodiscovery Space exhibit has a visible pedagogy. Finally, using the collected data I discuss the power tensions created in the production of expositive discourse showing how distributive, recontextualization and evaluation rules work in the context of exhibitions. The study of the dynamics in forming the expositive discourse using Bernstein’s framework reveals the individuals and institutions, the selection criteria, the negotiations and the power relations involved. It has the potential to assist both educators and researchers in the museum education field, as well as designers to understand the teaching and learning processes that occur during a visit and to establish relevant criteria to evaluate quality to best produce exhibitions in science museums.     

Cost economies in the provision of higher education for international students: Australian evidence

In the past few decades, the additional revenues available via higher education exports (through both relatively higher prices and increased enrolments) have attracted the attention of providers in many developed countries, not least in Anglophone countries like the USA, the UK, Canada and Australia. However, while the revenue case is strong, the institutional cost structures underlying the provision of higher education services for international students remain relatively unknown at the sector level. Accordingly, we offer a comprehensive analysis of the cost economies underlying higher education provision for international students using a sample of 37 Australian public universities over the period from 2003 to 2012. The findings suggest that it is appealing to enrol additional overseas students given their lower average and marginal costs and the significant economies of scale prevailing in higher education generally. Further, while we find evidence of economies of scope for overseas students only in smaller institutions, there is no evidence of diseconomies of scope, implying the current number of overseas students and their joint production with domestic students at the least does not lead to unnecessarily higher overall costs.     

Internet流量与负载均衡的研究

Load and traffic balancing for the Internet are analyzed. An intelligent domain name system(DNS) policy for the control and management of content distribution networks (CDN) is presented. An CDNs network based Urtitech IntelliDNS is built, and performance of the network in realizing traffic and load balancing is measured. It is proved that CDNs provide a valuable service and the methods are feasible.     

The moderating influence of instructional intensity and word type on the acquisition of academic vocabulary in young English language learners

This study used a within-subjects design to explore two instructional conditions for developing vocabulary in second-grade Spanish-speaking English learners (ELs)—extended instruction and embedded instruction implemented during shared interactive reading. Words assigned to the extended condition were directly taught using a multifaceted approach that included visuals, bilingual definitions, examples, spelling, and partner-talk about the words’ meaning. Words assigned to the embedded condition were taught solely through brief definitions to embedded text, writing activities, and songs. In the control condition students heard the target words read aloud during shared interactive reading but without definitions or direct instruction. The study also explored the interaction between instructional condition and word type. Four types of words—abstract cognates, abstract noncognates, concrete cognates, and concrete noncognates—were randomly assigned to each condition. Nine teachers in four schools and 187 second-grade ELs participated in this within-subjects intervention, which took place in transitional bilingual classrooms. Findings indicated that across all word types, both extended and embedded instruction were more effective than the control condition in helping ELs acquire vocabulary. Findings also indicated that extended instruction was more effective then embedded instruction for all word types except concrete cognates suggesting that these young Spanish-speaking ELs were advantaged by word knowledge in their home language. Finally, while embedded instruction was less effective than extended instruction, it was much more effective than a control condition. Embedded instruction takes significantly less preparation and instructional time than extended instruction, offering teachers a practical way to teach more vocabulary to ELs.     

Soft power as a policy rationale for international education in the UK: a critical analysis

This article presents the results of a textual analysis conducted on policy discourses on international students in the UK between 1999 and 2013. A number of rationales for and against increasing their numbers have been made, which have largely remained consistent over changing political administrations. One key rationale is that international students enhance the UK’s global political influence through its soft power. Critical analysis indicates that a number of unsubstantiated assumptions are made, representing international higher education and students in an outdated power relation predicated on Cold War politics. Key assumptions are that international students change their political attitudes and identify with the host country as a result of positive experiences. Later they are supposed to return home and reach positions of influence, which they exert in favour of the UK. They are represented to feel the same whether on scholarship or self-funded; and behave in predictable, similar ways. These representations of students as social subjects have disciplinary implications, which should be a topic for critical debate and potentially resistance in pedagogical contexts.     

Nearest-biclusters collaborative filtering based on constant and coherent values

Collaborative Filtering (CF) Systems have been studied extensively for more than a decade to confront the “information overload” problem. Nearest-neighbor CF is based either on similarities between users or between items, to form a neighborhood of users or items, respectively. Recent research has tried to combine the two aforementioned approaches to improve effectiveness. Traditional clustering approaches (k-means or hierarchical clustering) has been also used to speed up the recommendation process. In this paper, we use biclustering to disclose this duality between users and items, by grouping them in both dimensions simultaneously. We propose a novel nearest-biclusters algorithm, which uses a new similarity measure that achieves partial matching of users’ preferences. We apply nearest-biclusters in combination with two different types of biclustering algorithms—Bimax and xMotif—for constant and coherent biclustering, respectively. Extensive performance evaluation results in three real-life data sets are provided, which show that the proposed method improves substantially the performance of the CF process.