An Extensible and Personalized Approach to QoS-enabled Semantic Web Service Discovery

We present a framework for the autonomous discovery and selection of Semantic Web services based on their QoS properties. The novelty of our approach is the wide use of semantic technologies for a customizable discovery, which enables both the service users and providers to flexibly specify their matching models for QoS and the corresponding environmental conditions. In the presented approach, the discovery and ranking of services can be personalized via the use of domain ontologies detailing the user's preferences and the provider's specification. The discovery component is modeled as an adaptive query processing system in which the basic steps of filtering, matchmaking, reputation-based QoS assessment, and ranking of services correspond to logical algebraic operators, which facilitates the introduction of different discovery algorithms and the automatic generation of appropriate parallelized matchmaking evaluations, enabling the scalability of our solution up to unpredictable arrival rate of user queries against high numbers of published service descriptions in the system

An Extensible and Personalized Approach to QoS-enabled Service Discovery

We present an extensible and customizable framework for the autonomous discovery of Semantic Web services based on their QoS properties. Using semantic technologies, users can specify the QoS matching model and customize the ranking of services flexibly according to their preferences. The formal modeling of the discovery process as an adaptive query execution plan facilitates the introduction of different discovery algorithms and the automatic generation of parallelized matchmaking evaluations. This enables adapting our approach to unpredictable arrival rates of user queries and scales up to high numbers of published service descriptions

IDEAS-1997-2021-Final-Programs

This document records the final program for each of the 26 meetings of the International Database and Engineering Application Symposium from 1997 through 2021. These meetings were organized in various locations on three continents. Most of the papers published during these years are in the digital libraries of IEEE(1997-2007) or ACM(2008-2021)

An Extensible and Personalized Approach to QoS-enabled Service Discovery ∗

We present a framework for the autonomous discovery and selection of Semantic Web services based on their QoS properties. The novelty of our approach is the wide use of semantic technologies for a customizable discovery, which enables both the service users and providers to flexibly specify their matching models for QoS and the corresponding environmental conditions. In the presented approach, the discovery and ranking of services can be personalized via the use of domain ontologies detailing the user’s preferences and the provider’s specification. The discovery component is modeled as an adaptive query processing system in which the basic steps of filtering, matchmaking, reputation-based QoS assessment, and ranking of services correspond to logical algebraic operators, which facilitates the introduction of different discovery algorithms and the automatic generation of appropriate parallelized matchmaking evaluations, enabling the scalability of our solution up to unpredictable arrival rate of user queries against high numbers of published service descriptions in the system.

Configuration of service oriented architectures with semantic technologies based on non-functional requirements

Ова дисертација је фокусирана на примену семантичких технологија за решавање проблема оптималне конфигурације сервисно-оријентисаних архитектура (енгл. Service Oriented Architecture – SOA) на основу нефункционалних захтева корисника. Решење је базирано на проширењу АHP алгоритма за рад са различитим врстама захтева и развоју хеуристичког приступа заснованог на генетичким алгоритмима за решавање проблема оптималне конфигурације. Постојећа решења у овој области су показала изузетно мали ниво персонализације, тј корисницима није дозвољено дефинисање разних софистициранијих врста захтева који осликавају њихове жеље, очекивања и строге захтеве за које захтевају потпуно испуњење. Такође, постојећа решења су била перманентно фокусирана на испуњење захтева функционалности, након чега се врши одабир конфигурације сходно захтевима о смањењу вредности карактеристика које имају тенденцију раста (нпр., цена и време извршавања), односно повећању вредности карактеристика које имају тенденцију опадања (нпр., поузданост и доступност). Међутим, када се посматрају целе фамилије SOA, од посебног значаја постаје проблем конструкције конфигурације при истовременом задовољењу функционалних и нефункционалних захтева. Предложено интегрално решење под називом OptConfSOAFобезбеђује представљање различитих врста захтева (безусловни, условни, захтеви о лексикографском поретку) о нефункционалним карактеристикама и оптималну конфигурацију фамилија SOA на основу дефинисаних захтева. Приступ који се предлаже обезбеђује истовремено задовољење захтева који се тичу функционалности система као и нефункционалних захтева који могу бити различитог нивоа приоритета, односити се на поједине делове или сервисно- оријентисану архитектуру у целости. Предложено решење је опште и није ограничено само на веб сервисе, иако се појам семантичких технологија обично везује за дати домен примене. Решење се може применити у било ком домену у којем се SOA парадигма може применити посматрањем сервиса као било које компоненте (необавезно софтверске) дате функционалности...This dissertation is focused on the application of semantic technologies for solving the problem of optimal configuration of service-oriented architectures (SOA) based on stakeholders’ non-functional requirements. The proposed solution is developed as an extension of the AHP algorithm to allow for processing of different kinds of requirements. To address the problem of optimal configuration of SOA, a heuristic approach based on genetic algorithms has also been proposed and validated. Existing approaches in this field have shown low level of personalization, i.e. stakeholders are neither enabled to define sophisticated requirements that reflect their own expectations and attitudes, nor they are able to indicate hard requirements that have to be fully satisfied. Furthermore, existing approaches were primarily addressing the problem of fulfilling functional requirements, while the selection of an appropriate configuration is driven by the goal of decreasing the values of monotonically decreasing features (e.g., price and execution time) and simultaneous increasing the values of monotonically increasing features (e.g., availability and reliability). By considering the whole SOA families, the problem of configuration based on both functional and nonfunctional requirements gets special importance for research and further applications. The proposed solution, titled OptConfSOAF provides a framework for specification and processing of different kinds of requirements (unconditional, conditional, and requirements about lexicographical order) over non-functional features, and further optimal configuration of SOA families. The proposed approach provides simultaneous fulfillment of functional requirements (i.e., requirements related to the system’s functionalities) and non-functional requirements, where the latter could be defined with different level of importance, for specific parts of a SOA-based system or the system in its entirety. The proposed solution is general and is not bound to web services, even though semantic technologies are often associated with that domain. Since the solution considers a service as a component (no mandatory to be software component) with the specified functionality, it is applicable and easily adaptable to any specific application domain where SOA paradigm may be applied..

High Quality P2P Service Provisioning via Decentralized Trust Management

Trust management is essential to fostering cooperation and high quality service provisioning in several peer-to-peer (P2P) applications. Among those applications are customer-to-customer (C2C) trading sites and markets of services implemented on top of centralized infrastructures, P2P systems, or online social networks. Under these application contexts, existing work does not adequately address the heterogeneity of the problem settings in practice. This heterogeneity includes the different approaches employed by the participants to evaluate trustworthiness of their partners, the diversity in contextual factors that influence service provisioning quality, as well as the variety of possible behavioral patterns of the participants. This thesis presents the design and usage of appropriate computational trust models to enforce cooperation and ensure high quality P2P service provisioning, considering the above heterogeneity issues. In this thesis, first I will propose a graphical probabilistic framework for peers to model and evaluate trustworthiness of the others in a highly heterogeneous setting. The framework targets many important issues in trust research literature: the multi-dimensionality of trust, the reliability of different rating sources, and the personalized modeling and computation of trust in a participant based on the quality of services it provides. Next, an analysis on the effective usage of computational trust models in environments where participants exhibit various behaviors, e.g., honest, rational, and malicious, will be presented. I provide theoretical results showing the conditions under which cooperation emerges when using trust learning models with a given detecting accuracy and how cooperation can still be sustained while reducing the cost and accuracy of those models. As another contribution, I also design and implement a general prototyping and simulation framework for reputation-based trust systems. The developed simulator can be used for many purposes, such as to discover new trust-related phenomena or to evaluate performance of a trust learning algorithm in complex settings. Two potential applications of computational trust models are then discussed: (1) the selection and ranking of (Web) services based on quality ratings from reputable users, and (2) the use of a trust model to choose reliable delegates in a key recovery scenario in a distributed online social network. Finally, I will identify a number of various issues in building next-generation, open reputation-based trust management systems as well as propose several future research directions starting from the work in this thesis