particulate and gaseous emissions of pollutants from industries and auto-exhausts are responsible for rising discomfort, aggravates respiratory and cardiovascular. in this study, a system for air quality information in tehran city has been developed, using an online web-based geographic information system. this web-based gis application allows users to recognize areas with a potential increase ...

Low latency interactive data visualizations of large volumes of data are still rare on the web today. Their development requires expertise in server development, API design, dataflow optimization, and browser technologies; developers rarely have the time to optimize the whole stack from server to browser. To lift the burden of client-server co-development, we propose a system that generates vis...

by Vsevolod V. Panteleenko Traffic to a web server is unpredictable and very peaky. Such peaks can be up to ten times the average load. To avoid losing or alienating clients, web servers are overbuilt to handle the peak load. Consequently, there are huge investments in local infrastructure at web sites that are significantly underutilized except for infrequent peak periods. This dissertation de...

Query optimization in distributed databases is explicitly needed in many aspects of the optimization process, often making it imperative for the optimizer to consult underlying data sources while doing cost based optimization. This not only increases the cost of optimization, but also affects the trade-offs involved in the optimization process significantly. The leading cost in this optimizatio...

In this paper, we study a single server Markovian queue with state dependent accessible services, reneging and feedback of customers. The server can accommodate at the most $d$ customers in the service station, after which the new arrivals have to wait in the primary queue of infinite waiting space. All arrivals demand First Essential Service (FES), after completing FES, customers decide to joi...

ÐIn a wireless mobile client-server environment, a mobile user may voluntarily disconnect itself from the Web server to save its battery life and avoid high communication prices. To allow Web pages to be updated while the mobile user is disconnected from the Web server, updates can be staged in the mobile host and propagated back to the Web server upon reconnection. In this paper, we analyze al...