Optimizing storage of RDF archives using bidirectional delta chains

Linked Open Datasets on the Web that are published as RDF can evolve over time. There is a need to be able to store such evolving RDF datasets, and query across their versions. Different storage strategies are available for managing such versioned datasets, each being efficient for specific types of versioned queries. In recent work, a hybrid storage strategy has been introduced that combines these different strategies to lead to more efficient query execution for all versioned query types at the cost of increased ingestion time. While this trade-off is beneficial in the context of Web querying, it suffers from exponential ingestion times in terms of the number of versions, which becomes problematic for RDF datasets with many versions. As such, there is a need for an improved storage strategy that scales better in terms of ingestion time for many versions. We have designed, implemented, and evaluated a change to the hybrid storage strategy where we make use of a bidirectional delta chain instead of the default unidirectional delta chain. In this article, we introduce a concrete architecture for this change, together with accompanying ingestion and querying algorithms. Experimental results from our implementation show that the ingestion time is significantly reduced. As an additional benefit, this change also leads to lower total storage size and even improved query execution performance in some cases. This work shows that modifying the structure of delta chains within the hybrid storage strategy can be highly beneficial for RDF archives. In future work, other modifications to this delta chain structure deserve to be investigated, to further improve the scalability of ingestion and querying of datasets with many versions.

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The cost of homelessness: Assessing change over time

PsycEXTRA Dataset ◽

10.1037/e628672012-427 ◽

2003 ◽

Author(s):

M. Spano ◽

P. Toro ◽

M. Goldstein

Keyword(s):

Change Over Time ◽

The Cost ◽

Over Time

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The Internet Trap

10.23943/princeton/9780691159263.001.0001 ◽

2018 ◽

Author(s):

Matthew Hindman

Keyword(s):

The Internet ◽

Net Neutrality ◽

The Public ◽

Attention Economy ◽

Digital News ◽

The Cost ◽

Over Time

The Internet was supposed to fragment audiences and make media monopolies impossible. Instead, behemoths like Google and Facebook now dominate the time we spend online—and grab all the profits from the attention economy. This book explains how this happened. It sheds light on the stunning rise of the digital giants and the online struggles of nearly everyone else—and reveals what small players can do to survive in a game that is rigged against them. The book shows how seemingly tiny advantages in attracting users can snowball over time. The Internet has not reduced the cost of reaching audiences—it has merely shifted who pays and how. Challenging some of the most enduring myths of digital life, the book explains why the Internet is not the postindustrial technology that has been sold to the public, how it has become mathematically impossible for grad students in a garage to beat Google, and why net neutrality alone is no guarantee of an open Internet. It also explains why the challenges for local digital news outlets and other small players are worse than they appear and demonstrates what it really takes to grow a digital audience and stay alive in today's online economy. The book shows why, even on the Internet, there is still no such thing as a free audience.

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Classification of the factors forming the cost of the web-site

Voprosy regionalnoj ekonomiki ◽

10.21499/2078-4023-2017-31-2-82-89 ◽

2017 ◽

Vol 31 (2) ◽

pp. 82-89

Author(s):

E. S. Epifanov

Keyword(s):

Web Site ◽

Internet Site ◽

Advantages And Disadvantages ◽

Major Factors ◽

The Cost ◽

The Web

This article presents a classification of major factors that shape the cost of Internet site. Also discusses the limitations in determining the objectives of the web site; advantages and disadvantages of different factors.

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A Bibliometric Network Analysis of Coronavirus during the First Eight Months of COVID-19 in 2020

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18030952 ◽

2021 ◽

Vol 18 (3) ◽

pp. 952 ◽

Cited By ~ 1

Author(s):

Leonardo B. Furstenau ◽

Bruna Rabaioli ◽

Michele Kremer Sott ◽

Danielli Cossul ◽

Mariluza Sott Bender ◽

...

Keyword(s):

Decision Making ◽

Network Analysis ◽

Web Of Science ◽

Future Research ◽

Future Trends ◽

Damage Prevention ◽

Over Time ◽

The Web

The COVID-19 pandemic has affected all aspects of society. Researchers worldwide have been working to provide new solutions to and better understanding of this coronavirus. In this research, our goal was to perform a Bibliometric Network Analysis (BNA) to investigate the strategic themes, thematic evolution structure and trends of coronavirus during the first eight months of COVID-19 in the Web of Science (WoS) database in 2020. To do this, 14,802 articles were analyzed, with the support of the SciMAT software. This analysis highlights 24 themes, of which 11 of the more important ones were discussed in-depth. The thematic evolution structure shows how the themes are evolving over time, and the most developed and future trends of coronavirus with focus on COVID-19 were visually depicted. The results of the strategic diagram highlight ‘CHLOROQUINE’, ‘ANXIETY’, ‘PREGNANCY’ and ‘ACUTE-RESPIRATORY-SYNDROME’, among others, as the clusters with the highest number of associated citations. The thematic evolution. structure presented two thematic areas: “Damage prevention and containment of COVID-19” and “Comorbidities and diseases caused by COVID-19”, which provides new perspectives and futures trends of the field. These results will form the basis for future research and guide decision-making in coronavirus focused on COVID-19 research and treatments.

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A five-decade review of gender-based occupational segregation: A bibliometric study of influential authors, institutions, and research clusters

Australian Journal of Career Development ◽

10.1177/10384162211006951 ◽

2021 ◽

Vol 30 (2) ◽

pp. 117-128

Author(s):

Leena Sachdeva ◽

Kumkum Bharti ◽

Mridul Maheshwari

Keyword(s):

Wage Differential ◽

Web Of Science ◽

Occupational Segregation ◽

Extensive Field ◽

Organisational Structures ◽

Gender Based ◽

Changes Over Time ◽

Over Time ◽

The Web

Despite the proliferation of occupational segregation research, only a limited amount has explored it from a gender perspective. The attention that has been given is widely scattered and requires an analysis to identify the major works undertaken and the changes over time. This study aimed to examine and assimilate articles published on gender-based occupational segregation through a bibliometric analysis. The study examined 512 articles published from the early 1970s to 2020 that were retrieved from the Web of Science database. The findings suggest that gender and occupational segregation remain an extensive field of research, although this research comes mainly from North American and European countries. The low representation from developing countries indicates that more research is needed based on these different socio-cultural settings. This study identified three dominant research clusters, namely gendered organisational structures and systems, measurement of occupational segregation, and wage differential. Studies also covered areas including conceptualization, LGBTQ issues, and the role of legislation and institutions in reducing workplace inequalities; thus, providing a direction for scholars and practitioners.

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Value-based dentistry: Putting the patient first

Faculty Dental Journal ◽

10.1308/rcsfdj.2016.126 ◽

2016 ◽

Vol 7 (3) ◽

pp. 126-129 ◽

Cited By ~ 2

Author(s):

Sreenivas Koka ◽

Galya Raz

Keyword(s):

Risk Management ◽

Quality Improvement ◽

Quality Of Care ◽

Dental Care ◽

Time Cost ◽

Safety Risk ◽

The Cost ◽

Over Time

What does ‘value’ mean? In the context of dental care, it can be defined as the quality of care received by a patient divided by the cost to the patient of receiving that care. In other words: V =Q/C, where Q equals the quality improvement over time, which most patients view in the context of the outcome, the service provided and safety/risk management, and C equals the financial, biological and time cost to the patient. Here, the need for, and implications of, value-based density for clinicians and patients alike are explored.

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Progress and Prospects for the Development of Computer-Generated Actors for Military Simulation: Part 1-Introduction and Background

Presence Teleoperators & Virtual Environments ◽

10.1162/105474603765879558 ◽

2003 ◽

Vol 12 (3) ◽

pp. 311-325 ◽

Cited By ~ 4

Author(s):

Martin R. Stytz ◽

Sheila B. Banks

Keyword(s):

Research Area ◽

Background Information ◽

Life Cycle Costs ◽

Material Management ◽

Reasoning System ◽

Force Structure ◽

The Cost ◽

Future Work ◽

Level Training ◽

Made In

The development of computer-generated synthetic environments, also calleddistributed virtual environments, for military simulation relies heavily upon computer-generated actors (CGAs) to provide accurate behaviors at reasonable cost so that the synthetic environments are useful, affordable, complex, and realistic. Unfortunately, the pace of synthetic environment development and the level of desired CGA performance continue to rise at a much faster rate than CGA capability improvements. This insatiable demand for realism in CGAs for synthetic environments arises from the growing understanding of the significant role that modeling and simulation can play in a variety of venues. These uses include training, analysis, procurement decisions, mission rehearsal, doctrine development, force-level and task-level training, information assurance, cyberwarfare, force structure analysis, sustainability analysis, life cycle costs analysis, material management, infrastructure analysis, and many others. In these and other uses of military synthetic environments, computer-generated actors play a central role because they have the potential to increase the realism of the environment while also reducing the cost of operating the environment. The progress made in addressing the technical challenges that must be overcome to realize effective and realistic CGAs for military simulation environments and the technical areas that should be the focus of future work are the subject of this series of papers, which survey the technologies and progress made in the construction and use of CGAs. In this, the first installment in the series of three papers, we introduce the topic of computer-generated actors and issues related to their performance and fidelity and other background information for this research area as related to military simulation. We also discuss CGA reasoning system techniques and architectures.

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Confirming Anomalies

Review of Pacific Basin Financial Markets and Policies ◽

10.1142/s0219091521500247 ◽

2021 ◽

pp. 2150024

Author(s):

Peter Chinloy ◽

Matthew Imes

Keyword(s):

Capital Structure ◽

Stock Returns ◽

Cost Of Capital ◽

Simultaneous Equations ◽

Second Stage ◽

Predicted Values ◽

The Cost ◽

Over Time ◽

Identification Strategy

A procedure confirms whether a return-factor correlation is anomalous or results from endogenous simultaneous-equations bias. The identification strategy sorts the cost of capital components for instruments. In the first stage, the initially found factors are regressed on cost instruments. In the second stage, a confirmed anomaly has predicted value significant in returns and exogenous. Taxes, depreciation and capital structure are strong instruments, affecting 1980–2017 quarterly U.S. stock returns. Size, value and profitability decisions are significant in instruments. Returns increase in fitted profits, but not small size. Actual and predicted values have weaker correlation with returns over time.

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Health, Longevity, and Welfare Inequality of Older Americans

Review of Economics and Statistics ◽

10.1162/rest_a_01103 ◽

2021 ◽

pp. 1-45

Author(s):

Ray Miller ◽

Neha Bairoliya

Keyword(s):

Expected Utility ◽

Well Being ◽

Poor Health ◽

Cost Of Living ◽

Cross Sectional ◽

Older Americans ◽

The Cost ◽

Welfare Inequality ◽

Health And Mortality ◽

Over Time

Abstract We estimate the distribution of well-being among the older U.S. population using an expected utility framework that incorporates differences in consumption, leisure, health, and mortality. We find large disparities in welfare that have increased over time. Incorporating the cost of living with poor health into elderly welfare substantially increases the overall inequality. Disparity measures based on cross-sectional income or consumption underestimate the growth in aggregate welfare inequality. Moreover, health is a better indicator of an individual's relative welfare position than income or consumption.

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