Computer Science Journal (AGH University of Science and Technology, Krakow)
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Adaptive SOA Stack-based Business Process Monitoring Platform
Get PDFExecutable business processes that formally describe company activities are well placed in the SOA environment as they allow for declarative organization of high-level system logic.However, for both technical and non-technical users, to fully benet from that element of abstractionappropriate business process monitoring systems are required and existing solutions remain unsatisfactory.The paper discusses the problem of business process monitoring in the context of the service orientation paradigm in order to propose an architectural solution and provide implementation of a system for business process monitoring that alleviates the shortcomings of the existing solutions.Various platforms are investigated to obtain a broader view of the monitoring problem and to gather functional and non-functional requirements. These requirements constitute input forthe further analysis and the system design. The monitoring software is then implemented and evaluated according to the specied criteria.An extensible business process monitoring system was designed and built on top of OSGiMM - a dynamic, event-driven, congurable communications layer that provides real-time monitoring capabilities for various types of resources. The system was tested against the stated functional requirements and its implementation provides a starting point for the further work.It is concluded that providing a uniform business process monitoring solution that satises a wide range of users and business process platform vendors is a dicult endeavor. It is furthermore reasoned that only an extensible, open-source, monitoring platform built on top of a scalablecommunication core has a chance to address all the stated and future requirements
INTEGRATION OF DATA FROM HETEROGENEOUS SOURCES USING ETL TECHNOLOGY.
Get PDFData integration is a crucial issue in environments of heterogeneous data sources. At present mentioned heterogeneity is becoming widespread. Whenever, based on various data sources, we want to gain useful information and knowledge we must solve data integration problem in order to apply appropriate analytical methods on comprehensive and uniform data. Such activity is known as knowledge discovery from data process. Therefore approaches to data integration problem are very interesting and bring us closer to the "age of information". The paper presents an architecture, which implements knowledge discovery from data process. The solution combines ETL technology and wrapper layer known from mediated systems. It also provides semantic integration through connections mechanism between data elements. The solution allows for integration of any data sources and implementation of analytical methods in one environment. The proposed environment is verified by applying it to data sources on the foundry industry
COMPLEX EVENT PROCESSING APPROACH TO AUTOMATED MONITORING OF PARTICLE ACCELERATOR AND ITS CONTROL SYSTEM
Get PDFThis article presents the design and implementation of a software component for automated monitoring and diagnostic information analysis of a particle accelerator and its control system. The information that is analyzed can be seen as streams of events. A Complex Event Processing (CEP) approach to event processing was selected. The main advantage of this approach is the ability to continuously query data coming from several streams. The presented software component is based on Esper, the most popular open-source implementation of CEP. As a test bed, the control system of the accelerator complex located at CERN, the European Organization for Nuclear Research, was chosen. The complex includes the Large Hadron Collider, the world’s most powerful accelerator. The main contribution to knowledge is by showing that the CEP approach can successfully address many of the challenges associated with automated monitoring of the accelerator and its control system that were previously unsolved. Test results, performance analysis, and a proposal for further works are also presented
Network Resilience Analysis: Review of Concepts and a Country-Level. Case Study
Get PDFThis paper presents the rationale behind performing an analysis of Internet resilience in the sense of maintaining a connection of autonomous systems in the presence of failures or attacks — on a level of a single country. Next, the graph of a network is constructed that represents interconnections between autonomous systems. The connectivity of the graph is examined for cases of link or node failure. Resilience metrics are proposed, focusing on a single autonomous system or on overall network reliability. The process of geographic location of networking infrastructure is presented, leading to an analysis of network resilience in the case of a joint failure of neighboring autonomous systems
Model checking processes specified in join-calculus algebra
Get PDFThis article presents a model checking tool used to verify concurrent systems specified in join-calculus algebra. The temporal properties of systems under verification are expressed in CTL logic. Join-calculus algebra with its operational semantics defined by the chemical abstract machine serves as the basic method for the specification of concurrent systems and their synchronization mechanisms, and allows the examination of more complex systems
Semantic Text Indexing
Get PDFThis article presents a specific issue of the semantic analysis of texts in natural language – text indexing and describes one field of its application (web browsing).The main part of this article describes the computer system assigning a set of semantic indexes (similar to keywords) to a particular text. The indexing algorithm employs a semantic dictionary to find specific words in a text, that represent a text content. Furthermore it compares two given sets of semantic indexes to determine texts’ similarity (assigning numerical value). The article describes the semantic dictionary – a tool essentialto accomplish this task and its usefulness, main concepts of the algorithm and test results
Experimental verification of Hyper-V performance isolation level
Get PDFThe need for cost optimization in a broad sense constitutes the basis of operation of every enterprise. In the case of IT structure, which is present in almost every field of activity these days, one of the most commonly applied technologies leading to good cost-to-profit adjustment is virtualization. It consists in locating several operational systems with IT systems on a single server. In order for such optimization to be carried out correctly it has to be strictly controlled by means of allocating access to resources, which is known as performance isolation. Modern virtualizers allow to set up this allocation in quantitative terms (the number of processors, size of RAM, or disc space). It appears, however, that in qualitative terms (processor\u27s time, RAM or hard disc bandwidth) the actual allocation of resources does not always correspond with this configuration. This paper provides an experimental presentation of the achievable level of performance isolation of the Hyper-V virtualizer
Turing machine approach to runtime software adaptation
Get PDFIn this paper, the problem of applying changes to software at runtime is considered. The computability theory is used in order to develop a more general and programming-language-independent model of computation with support for runtime changes. Various types of runtime changes were defined in terms of computable functions and Turing machines. The properties of such functions and machines were used to prove that arbitrary runtime changes on Turing machines are impossible in general cases. A method of Turing machine decomposition into subtasks was presented and runtime changes were defined through transformations of the subtask graph. Requirements for the possible changes were considered with regard to the possibility of subtask execution during such changes. Finally, a runtime change model of computation was defined by extension of the Universal Turing Machine
An algorithm of semi-Delaunay triangulation of points cloud scattered on surface
Get PDFThe purpose of the paper is to generalize the Delaunay triangulation onto surfaces. A formal definition and appropriate algorithm are presented. Starting from plane domain Delaunay triangulation definition a theoretical approach is evolved which is a background for further considerations. It is proved that in case of plane surface the introduced Delaunay triangulation of surfaces is identical with classical Delaunay triangulation of plane domain. The proposed algorithm is implemented and numerical results are shown
URBANCONTEXT: A MANAGEMENT MODEL FOR PERVASIVE ENVIRONMENTS IN USER-ORIENTED URBAN COMPUTING
Get PDFNowadays, urban computing has gained a lot of interest for guiding the evolution of citiesinto intelligent environments. These environments are appropriated for individuals’ inter-actions changing in their behaviors. These changes require new approaches that allow theunderstanding of how urban computing systems should be modeled.In this work we present UrbanContext, a new model for designing of urban computingplatforms that applies the theory of roles to manage the individual’s context in urban envi-ronments. The theory of roles helps to understand the individual’s behavior within a socialenvironment, allowing to model urban computing systems able to adapt to individuals statesand their needs.UrbanContext collects data in urban atmospheres and classifies individuals’ behaviorsaccording to their change of roles, to optimize social interaction and offer secure services.Likewise, UrbanContext serves as a generic model to provide interoperability, and to facilitatethe design, implementation and expansion of urban computing systems