An adaptive admission control and load balancing algorithm for a QoS-aware Web system

The main objective of this thesis focuses on the design of an adaptive algorithm for admission control and content-aware load balancing for Web traffic. In order to set the context of this work, several reviews are included to introduce the reader in the background concepts of Web load balancing, admission control and the Internet traffic characteristics that may affect the good performance of a Web site. The admission control and load balancing algorithm described in this thesis manages the distribution of traffic to a Web cluster based on QoS requirements. The goal of the proposed scheduling algorithm is to avoid situations in which the system provides a lower performance than desired due to servers' congestion. This is achieved through the implementation of forecasting calculations. Obviously, the increase of the computational cost of the algorithm results in some overhead. This is the reason for designing an adaptive time slot scheduling that sets the execution times of the algorithm depending on the burstiness that is arriving to the system. Therefore, the predictive scheduling algorithm proposed includes an adaptive overhead control. Once defined the scheduling of the algorithm, we design the admission control module based on throughput predictions. The results obtained by several throughput predictors are compared and one of them is selected to be included in our algorithm. The utilisation level that the Web servers will have in the near future is also forecasted and reserved for each service depending on the Service Level Agreement (SLA). Our load balancing strategy is based on a classical policy. Hence, a comparison of several classical load balancing policies is also included in order to know which of them better fits our algorithm. A simulation model has been designed to obtain the results presented in this thesis

The deterrent effect of voting against minarets: identity utility and foreigners' location choice

This paper uses the vote on the Swiss minaret initiative as a natural experiment to identify the causal effect of negative attitudes towards immigrants on foreigners' location choices and thus indirectly on their utility. Based on a regression discontinuity design with unknown discontinuity points and administrative data on the population of foreigners, we find that the probability of their moving to a municipality that unexpectedly expressed strong reservations decreases initially by about 60 percent. The effect levels off over a period of about 5 months. Consistent with a reduction in the identity utility for immigrants in general, the reaction is not confined to Muslims, whereby high-skilled foreigners seem to be most sensitive to the newly revealed reservations

The need of standardization and the potential role of voluntary approaches: Issues and trends in Italian GCHP market

Despite the lack of specific incentives, Ground Coupled Heat Pumps (GCHP) installations are booming in Italy both in private and public sectors of the market. Such rapid growth entails an increasing concern for environmental and technical performances since no comprehensive regulation and reliable standards exist yet. By means of an investigation of sectoral opinion leaders and SWOT-based technique for building scenarios, this paper discusses potential schemes for balancing mandatory and voluntary requirements. The analysis suggests that standardization and voluntary schemes are perceived as effective tools to encourage the greening of Italian GCHP-SMEs in short-run while laying the foundations for evolving sustainable policies in the longer run. A potential scheme that has been simulated by reflecting the supply-side orientations of the market and that involves of process and product standards is discussed.

Special Libraries, February 1964

Volume 55, Issue 2https://scholarworks.sjsu.edu/sla_sl_1964/1001/thumbnail.jp

Special Libraries, October 1956

Volume 47, Issue 8https://scholarworks.sjsu.edu/sla_sl_1956/1007/thumbnail.jp

Context Aware Computing for The Internet of Things: A Survey

As we are moving towards the Internet of Things (IoT), the number of sensors deployed around the world is growing at a rapid pace. Market research has shown a significant growth of sensor deployments over the past decade and has predicted a significant increment of the growth rate in the future. These sensors continuously generate enormous amounts of data. However, in order to add value to raw sensor data we need to understand it. Collection, modelling, reasoning, and distribution of context in relation to sensor data plays critical role in this challenge. Context-aware computing has proven to be successful in understanding sensor data. In this paper, we survey context awareness from an IoT perspective. We present the necessary background by introducing the IoT paradigm and context-aware fundamentals at the beginning. Then we provide an in-depth analysis of context life cycle. We evaluate a subset of projects (50) which represent the majority of research and commercial solutions proposed in the field of context-aware computing conducted over the last decade (2001-2011) based on our own taxonomy. Finally, based on our evaluation, we highlight the lessons to be learnt from the past and some possible directions for future research. The survey addresses a broad range of techniques, methods, models, functionalities, systems, applications, and middleware solutions related to context awareness and IoT. Our goal is not only to analyse, compare and consolidate past research work but also to appreciate their findings and discuss their applicability towards the IoT.Comment: IEEE Communications Surveys & Tutorials Journal, 201

Monitoring land use changes using geo-information : possibilities, methods and adapted techniques

Monitoring land use with geographical databases is widely used in decision-making. This report presents the possibilities, methods and adapted techniques using geo-information in monitoring land use changes. The municipality of Soest was chosen as study area and three national land use databases, viz. Top10Vector, CBS land use statistics and LGN, were used. The restrictions of geo-information for monitoring land use changes are indicated. New methods and adapted techniques improve the monitoring result considerably. Providers of geo-information, however, should coordinate on update frequencies, semantic content and spatial resolution to allow better possibilities of monitoring land use by combining data sets