Verteilte Metadatenverwaltung und Anfragebearbeitung für Internet-Datenquellen     

Markus Keidl  Alfons Kemper  Donald Kossmann und Alexander Kreutz 《Informatik - Forschung und Entwicklung》2002,17(3):123-134

Zusammenfassung.   Wir pr?sentieren in dieser Arbeit das ObjectGlobe-System, ein offenes und verteiltes Anfragebearbeitungssystem auf Internet-Datenquellen. ObjectGlobe erweitert die begrenzten F?higkeiten des Internets bezüglich Anfragebearbeitung, indem es einen offenen Marktplatz schafft, in dem eine Vielzahl von Anbietern Rechenzeit, Daten und Anfrageoperatoren bereitstellen. Den Schwerpunkt dieses Beitrags bildet die im Rahmen des ObjectGlobe-Projekts entwickelte Metadatenverwaltung MDV, ein verteiltes Metadaten-Management-System. Es besitzt eine 3-schichtige Architektur und unterstützt Caching und Replikation in der Mittelschicht, so dass Anfragen lokal ausgewertet werden k?nnen. Benutzer spezifizieren die Informationen, die sie ben?tigen und die repliziert werden, mit Hilfe einer besonderen Regelsprache. Um Replikate aktuell zu halten und die Replikation von neuen und relevanten Informationen anzusto?en, verwendet das MDV-System einen neuartigen Publish & Subscribe-Algorithmus. Wir beschreiben diesen Algorithmus im Detail und zeigen, wie er mit Hilfe eines normalen relationalen Datenbanksystems implementiert werden kann. Eingegangen am 19. November 2001 / Angenommen am 30. Juli 2002  相似文献   

The metallurgy and assaying of the precious metals used in coinage     

Alexander E. Outerbridge 《Journal of The Franklin Institute》1877,103(4):281-290

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Questioning the pace and pathway of e-government development in Africa: A case study of South Africa's Cape Gateway project     

Blessing Mukabeta Maumbe  Vesper Owei  Helen Alexander 《Government Information Quarterly》2008

The paper examines e-government development in Africa. This study is based on the Cape Gateway project in South Africa, a leading e-government initiative on the continent. We observe that African countries have jumped on the e-government band wagon by looking mostly at the benefits without a clear risk assessment. We argue that African countries should question the pace and pathway for their e-government programs. We caution that e-government models from developed countries do not necessarily work in Africa. E-government programs in Africa should be balanced with the provision of basic needs and infrastructure. We conclude that e-government in South Africa should adopt multi-cultural approaches, and must be underpinned by national development priorities. We recommend that the Cape Gateway must address the socio-economic context and needs of the country. The pace and pathway of its e-government must depend on the availability of both financial and human resources and also user satisfaction.  相似文献   

Excluding archival silences: Oral history and historical absence     

Ben Alexander 《Archival Science》2005,5(2-4):1-11

Despite our society's increasing reliance on electronic documentation, to-date archives remain, largely, material repositories of cultural memory. It is an accepted historical problematic, however, that culture is often resistant to material preservation. There exists an undeniable and profound tension between scholarly efforts to reconstruct history and interpret cultural traditions and the fragmentary, and often limited, material record. That is to say, scholarship is shaped by a sinuous negotiation around the historical silences that encompass all of material culture. Historical silences, however, can at times be marginalized (or at best excluded) by a sensitive configuration of material evidence with oral history.Excluding Archival Silences: Oral History and Historical Absence uses a historically and geographically specific example of oral history to engage in a more generalist discussion of how oral reflection, especially when shaped by material evidences, can be an especially effective tool for preserving the dynamics of culture that often remain undocumented.  相似文献   

Consolidation of Black-dyed Māori Textile Artefacts: Evaluating the Efficacy of Sodium Alginate     

Catherine A. Smith  Rachel A. Paterson  Bronwyn J. Lowe  Rangi Te Kanawa 《文物保护研究》2018,63(3):139-154

Black-dyed artefacts are found in museums worldwide, many produced using an iron-tannate compound. Deterioration of iron-tannate dyed artefacts is an international preservation issue: in New Zealand the deterioration of paru (iron-tannate) dyed Māori textiles is widespread. This article reports experimental work testing the efficacy of sodium alginate, a consolidant developed for deteriorated paru-dyed muka (fibre from harakeke; Phormium tenax). The colour stability, strength retention, and acidity of paru-dyed muka consolidated with sodium alginate (0.25, 0.5, and 1% w/v in water) was tested pre- and post-artificial light ageing. This study found that sodium alginate had no negative effect on paru-dyed muka and in some cases provided benefit. Interestingly, the colour of paru-dyed muka is substantially more stable in UV-filtered light than previously recognised. Also microfading results were in agreement with visual assessments of colour change at 1 Mlux hour exposure, providing confidence in this relatively new technique to assess colour change.  相似文献   

Supportive communication from bystanders of cyberbullying: indirect effects and interactions between source and message characteristics     

Andrew C. High  Rachel Young 《Journal of Applied Communication Research》2018,46(1):28-51

Cyberbullying is an increasingly common experience that produces psychosocial consequences for targets. Interventions encouraging bystanders to support targets of cyberbullying are limited by a lack of focus on what to communicate. This study considers supportive messages that emphasize emotional comfort, attributions of responsibility, and beliefs that people can change as relevant to this context, and it examines how perceptions of messages differ based on whether support providers have or lack experience with cyberbullying. We extend research on the indirect effects model of supportive communication by randomly assigning participants (N?=?304), who self-identify as targets of cyberbullying, to message and source conditions and assessing their perceptions of messages, providers, and outcomes. Impressions of messages mediate their influence on outcomes, and the experiential similarity of support providers moderates these effects. Certain messages, notably those contending that bullies can change, are less effective when delivered by sources who lack experience with bullying.  相似文献   

How we done it good: Research through design as a legitimate methodology for librarianship     

Rachel Ivy Clarke 《Library & information science research》2018,40(3-4):255-261

“How we done it good” publications—a genre concerning project-based approaches that describe how (and sometimes why) something was done—are often rebuked in the library research community for lacking traditional scientific validity, reliability, and generalizability. While scientific methodologies may be a common approach to research and inquiry, they are not the only methodological paradigms. This research posits that the how we done it good paradigm in librarianship reflects a valid and legitimate approach to research. By drawing on the concept of research through design, this study shows how these how we done it good projects reflect design methodologies which draw rigor from process, invention, relevance, and extensibility rather than replicability, generalizability, and predictability. Although these projects implicitly reflect research through design, the methodology is not yet explicitly harnessed in librarianship. More support for these types of projects can be achieved by making the legitimate design framework more explicit and increasing support from publication venues.  相似文献   

The secrets of failing better: Accessible publishing at SAGE. A case study          下载免费PDF全文

Caroline Manis  Huw Alexander 《Learned Publishing》2018,31(1):63-68

Key points

• Accessibility is often misunderstood as a concept that is niche or of secondary importance.
• Reframing accessibility as improving the overall user experience instantly changes the perspective; accessibility becomes a critical requirement worthy of investment and resources.
• The single most prevalent complaint amongst librarians is the time it takes to get hold of accessible content.
• An accessibility roadmap provides structure and transparency for digital accessibility projects within the organization.
• Publishers' non‐compliance with accessibility standards will increase their risk of sales declines and legal complications over time.
• The SAGE A.C.C.E.S.S.I.B.L.E mnemonic offers suggestions on how to devise a successful accessible publishing programme.

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Investigating married adults’ communal coping with genetic health risk and perceived discrimination     

Rachel A. Smith  Alan Sillars  Ryan P. Chesnut  Xun Zhu 《Communication monographs》2018,85(2):181-202

Increased genetic testing in personalized medicine presents unique challenges for couples, including managing disease risk and potential discrimination as a couple. This study investigated couples’ conflicts and support gaps as they coped with perceived genetic discrimination. We also explored the degree to which communal coping was beneficial in reducing support gaps and ultimately stress. Dyadic analysis of married adults (N?=?266, 133 couples), in which one person had the genetic risk for serious illness, showed that perceived discrimination predicted more frequent conflicts about alpha-1 antitrypsin deficiency-related treatment, privacy boundaries, and finances, which, in turn, predicted wider gaps in emotion and esteem support, and greater stress for both spouses. Communal coping predicted lower support gaps for both partners and marginally lower stress.  相似文献   

Parental perceptions of gender differences in child technology use and cyberbullying     

Mallory Bolenbaugh  Megan Foley-Nicpon  Rachel Young  Melissa Tully  Nikki Grunewald  Marizen Ramirez 《Psychology in the schools》2020,57(11):1657-1679

Cyberbullying is a major health concern for today's youth and a pervasive stressor for adolescents and their families. This study offers qualitative insights into how parents perceive their children's technology use and engagement in cyberbullying based on gender. Eight focus groups were conducted with 48 parents of adolescents ages 10–17. Findings indicated parents perceived their children overuse technology and lack awareness of what cyberbullying is. Specific to gender, parents suggested their daughters use technology for social connection, and parents were more concerned about their daughter's technology use than their son's, which they believed was related to specific interests. In response to cyberbullying scenarios, parents encouraged females but not males to socialize with peers. This is the first qualitative study to obtain an in-depth understanding of the ways in which parents perceive and socialize their children in regard to technology use and cyberbullying scenarios. These results may help school systems, school psychologists, researchers, and parents gain awareness of the gender-stereotypical socialization process that unfolds in parental monitoring of technology use and cyberbullying situations. We conclude by offering suggestions for how school systems and personnel might intervene.  相似文献