Verteilte Metadatenverwaltung und Anfragebearbeitung für Internet-Datenquellen

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     

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

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.     

Reply to the Comments

First, I am pleased to note the broad area of agreement amongthe four of us. We concur fully that polls are useful, powerful,and play an important role in contemporary politics. My threeresponders also acknowledge the significance of alternativeways in which citizens can express their opinions and, furthermore,that public opinion is more diverse and nuanced than any dichotomoussplit between the pros and cons on a particular issue recordedat a particular time might suggest. Sir Robert chides me explicitly, and Gary Langer by implication,for failing     

从加强学科建设谈高校图书馆数字化信息服务

从加强高校学科建设、培养和造就高水平学科带头人出发,分析高校图书馆数字化信息服务的现状,论述高校图书馆数字化信息服务的具体措施。     

一代图书馆学人的心路历程——纪念首届中青会20周年(下)

文章纪录了上世纪80年代走入图书馆领域的一代图书馆学人所经历的学术历程,描述了他们作为一个十分重要的学术群体在理论和实践方面对我国图书馆学和图书馆事业的重要贡献。     

Excluding archival silences: Oral history and historical absence

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.     

The secrets of failing better: Accessible publishing at SAGE. A case study

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.

     

用数学建模竞赛的思想指导师范生毕业论文的写作

针对高等师范院校数学专业毕业论文的现状和存在的问题,阐述了毕业论文改革的必要性和可行性,提出了遵循数学建模竞赛的思想和方法来指导师范生毕业论文写作的新模式,并且给出了按照数学建模竞赛的思想和方法进行师范生毕业论文选题和撰写的建议。