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- Creators: Schubert, Franz, 1797-1828
Description
In recent years, service oriented computing (SOC) has become a widely accepted paradigm for the development of distributed applications such as web services, grid computing and cloud computing systems. In service-based systems (SBS), multiple service requests with specific performance requirements make services compete for system resources. IT service providers need to allocate resources to services so the performance requirements of customers can be satisfied. Workload and performance models are required for efficient resource management and service performance assurance in SBS. This dissertation develops two methods to understand and model the cause-effect relations of service-related activities with resources workload and service performance. Part one presents an empirical method that requires the collection of system dynamics data and the application of statistical analyses. The results show that the method is capable to: 1) uncover the impacts of services on resource workload and service performance, 2) identify interaction effects of multiple services running concurrently, 3) gain insights about resource and performance tradeoffs of services, and 4) build service workload and performance models. In part two, the empirical method is used to investigate the impacts of services, security mechanisms and cyber attacks on resources workload and service performance. The information obtained is used to: 1) uncover interaction effects of services, security mechanisms and cyber attacks, 2) identify tradeoffs within limits of system resources, and 3) develop general/specific strategies for system survivability. Finally, part three presents a framework based on the usage profiles of services competing for resources and the resource-sharing schemes. The framework is used to: 1) uncover the impacts of service parameters (e.g. arrival distribution, execution time distribution, priority, workload intensity, scheduling algorithm) on workload and performance, and 2) build service workload and performance models at individual resources. The estimates obtained from service workload and performance models at individual resources can be aggregated to obtain overall estimates of services through multiple system resources. The workload and performance models of services obtained through both methods can be used for the efficient resource management and service performance assurance in SBS.
ContributorsMartinez Aranda, Billibaldo (Author) / Ye, Nong (Thesis advisor) / Wu, Tong (Committee member) / Sarjoughian, Hessam S. (Committee member) / Pan, Rong (Committee member) / Arizona State University (Publisher)
Created2012
Description
Analysis of political texts, which contains a huge amount of personal political opinions, sentiments, and emotions towards powerful individuals, leaders, organizations, and a large number of people, is an interesting task, which can lead to discover interesting interactions between the political parties and people. Recently, political blogosphere plays an increasingly important role in politics, as a forum for debating political issues. Most of the political weblogs are biased towards their political parties, and they generally express their sentiments towards their issues (i.e. leaders, topics etc.,) and also towards issues of the opposing parties. In this thesis, I have modeled the above interactions/debate as a sentimental bi-partite graph, a bi-partite graph with Blogs forming vertices of a disjoint set, and the issues (i.e. leaders, topics etc.,) forming the other disjoint set,and the edges between the two sets representing the sentiment of the blogs towards the issues. I have used American Political blog data to model the sentimental bi- partite graph, in particular, a set of popular political liberal and conservative blogs that have clearly declared positions. These blogs contain discussion about social, political, economic issues and related key individuals in their conservative/liberal view. To be more focused and more polarized, 22 most popular liberal/conservative blogs of a particular time period, May 2008 - October 2008(because of high intensity of debate and discussions), just before the presidential elections, was considered, involving around 23,800 articles. This thesis involves solving the questions: a) which is the most liberal/conservative blogs on the web? b) Who is on which side of debate and what are the issues? c) Who are the important leaders? d) How do you model the relationship between the participants of the debate and the underlying issues?
ContributorsThirumalai, Dananjayan (Author) / Davulcu, Hasan (Thesis advisor) / Sarjoughian, Hessam S. (Committee member) / Sen, Arunabha (Committee member) / Arizona State University (Publisher)
Created2012
Description
Determining the factors associated with the availability of healthy and unhealthy foods in the household may help in understanding the varying complexities that contribute to obesity among children and help design interventions to impact children's food consumption behaviors. This study examined factors that are associated with the availability of healthy and unhealthy foods in children's home food environments (HFE). Data was collected from a random-digit-dial telephone survey of 1708 households, with at least one child between 3-18 years of age, located in five low-income New Jersey cities. HFE was assessed based on responses to a set of six items that measured availability of specific healthy and unhealthy foods in the respondent's home. These items contributed to construction of three HFE scales used as dependent variables in these analyses: healthy HFE, unhealthy HFE, and a ratio of healthy to unhealthy foods in the HFE. Independent variables included household socio-demographics, parental perceptions of their own weight and diet health, frequency of family meals, proximity to food outlets, and perception of access to healthy foods in the neighborhood food environment. Significant differences were observed in the HFE by race and ethnicity, with Non-Hispanic black children having fewer healthy foods and Non-Hispanic white children having more unhealthy food items available at home. Parents who reported being overweight or obese had a healthier HFE and those perceiving their own eating as healthy had more healthy and less unhealthy foods in the household. Food-secure households had more unhealthy compared to healthy foods at home. Households located farther from a supermarket had a greater number of unhealthy food items and a lower healthy/unhealthy food availability ratio. Parental perception of better access to fruits and vegetables and low-fat foods was associated with availability of a greater number of healthy food items at home. Overall, the HFE varied by parental and demographic characteristics, parental perceptions about the food environment and the actual features of the built neighborhood food environment.
ContributorsBerry, Andrea (Author) / Ohri-Vachaspati, Punam (Thesis advisor) / Johnston, Carol (Committee member) / Wharton, Christopher (Christopher Mack), 1977- (Committee member) / Arizona State University (Publisher)
Created2012
Description
The adoption of the Service Oriented Architecture (SOA) as the foundation for developing a new generation of software systems - known as Service Based Software Systems (SBS), poses new challenges in system design. While simulation as a methodology serves a principal role in design, there is a growing recognition that simulation of SBS requires modeling capabilities beyond those that are developed for the traditional distributed software systems. In particular, while different component-based modeling approaches may lend themselves to simulating the logical process flows in Service Oriented Computing (SOC) systems, they are inadequate in terms of supporting SOA-compliant modeling. Furthermore, composite services must satisfy multiple QoS attributes under constrained service reconfigurations and hardware resources. A key desired capability, therefore, is to model and simulate not only the services consistent with SOA concepts and principles, but also the hardware and network components on which services must execute on. In this dissertation, SOC-DEVS - a novel co-design modeling methodology that enables simulation of software and hardware aspects of SBS for early architectural design evaluation is developed. A set of abstractions representing important service characteristics and service relationships are modeled. The proposed software/hardware co-design simulation capability is introduced into the DEVS-Suite simulator. Exemplar simulation models of a communication intensive Voice Communication System and a computation intensive Encryption System are developed and then validated using data from an existing real system. The applicability of the SOC-DEVS methodology is demonstrated in a simulation testbed aimed at facilitating the design & development of SBS. Furthermore, the simulation testbed is extended by integrating an existing prototype monitoring and adaptation system with the simulator to support basic experimentation towards design & development of Adaptive SBS.
ContributorsMuqsith, Mohammed Abdul (Author) / Sarjoughian, Hessam S. (Thesis advisor) / Yau, Sik-Sang (Thesis advisor) / Huang, Dijiang (Committee member) / Tsai, Wei-Tek (Committee member) / Arizona State University (Publisher)
Created2011
ContributorsSchubert, Franz, 1797-1828 (Composer)
ContributorsSchubert, Franz, 1797-1828 (Composer)
ContributorsSchubert, Franz, 1797-1828 (Composer)
ContributorsSchubert, Franz, 1797-1828 (Composer)
ContributorsSchubert, Franz, 1797-1828 (Composer)
ContributorsSchubert, Franz, 1797-1828 (Composer)