Developing Data Warehouse Systems requires specifications of the underlying business need in the form of information models. The development of information models is often both expensive and extensive. Against this background, reference models provide useful means to reduce the costs of information modelling, because they can be used as a starting point for the construction of project-specific ...

Herbivores often specialize on particular hosts that provide both food and shelter from natural enemies. It is thus often unclear whether a plant’s value as a food or its value as a safe shelter has played a larger role in selecting for specialization. Decorator crabs offer a novel opportunity to investigate the relative effects of diet vs. natural enemies in selecting for specialization becaus...

In this article, I describe efforts to manage the capacity of homeless shelter programs in Philadelphia and assess the impact of those efforts on providers and consumers of homeless services. Most reforms have focused on reducing the capacity of the shelter system by reducing the average length of stay of persons in shelter and by providing housing relocation assistance. However, these reforms ...

Coral reef fish density and species richness are often higher at sites with more structural complexity. This association may be due to greater availability of shelters, but surprisingly little is known about the size and density of shelters and their use by coral reef fishes. We quantified shelter availability and use by fishes for the first time on a Caribbean coral reef by counting all holes ...

Materialized view selection is one of the crucial decisions in designing a data warehouse for optimal efficiency. Static selection of views may materialize certain views that are not beneficial as the data and usage trends change over time. On the contrary, dynamic selection of views works better only for queries demanding a high degree of aggregation. These facts point to the need for a techni...

Abstract Objective To quantitatively evaluate the effectiveness of Fangcang shelter hospitals, designated and time interval from illness onset to diagnosis toward prevention control COVID-19 epidemic. Methods We used SEIAR SEIA-CQFH warehouse models simulate two-period epidemic in Wuhan calculate dependent basic reproduction numbers (BRNs) symptomatic infected individuals, asymptomatic exposed ...

Database federation is becoming an increased reality for business and clinical organizations due to rapid data accumulation, making a single, monolithic data warehouse difficult to achieve. A commonly used technique to decrease query execution time in data warehousing environments is to precompute and store beneficial views. Known as the view selection problem, this process seeks to identify th...

Since a data warehouse deals with huge amounts of data and complex analytical queries, online processing and answering to users’ queries in data warehouses can be a serious challenge. Materialized views are used to speed up query processing rather than direct access to the database in on-line analytical processing. Since the large number and high volume of views prevents all of the views from b...