Publikacje

K.Sapiecha, D.Grela, Test scenarios generation for a class of processes defined in the BPEL language, International Conference On Computer Science - Research and Applications (IBIZA 2008), Annales UMCS - Informatica, Volume 8, Number 2/2008, pp.77-89

The main purpose of this research is an adaptation of critical paths method to processes defined in BPEL. Critical path method is specification based and simulation oriented method. In the paper it is showed that under some assumptions BPEL process may be considered as an embedded system, in which tasks are like services and communication between tasks is like coordination of the services according to task graph of the system. An example is given where a set of test scenarios is presented.

K.Sapiecha, D.Grela, Automating test case generation for requirements specification for processes orchestrating web services, 10^th International Conference on Enterprise Information Systems (ICEIS 2008), Barcelona, Spain, Information Systems Analysis and Specification vol.1/2008, pp.381-384

The research concerns generation of test cases for processes defined in BPEL. In the paper it is showed that under some assumptions BPEL process may be considered as an embedded system in which tasks are like services and communication between tasks is like coordination of the services according to task graph of the system. Following this analogy a new method for automating test case generation for requirements specification for processes defined in BPEL is given. An example illustrating the method is presented.

K.Sapiecha, D.Grela, Wyznaczanie scenariuszy testowych dla pewnej klasy procesów definiowanych za pomocą języka BPEL, Czasopismo Techniczne, z. 1-I/2008, ISSN 0011-4561, ISSN 1897-631X

Celem pracy jest adaptacja metody ścieżki krytycznej do procesów definiowanych w języku BPEL. W artykule pokazano, iż po spełnieniu kilku założeń proces BPELa możne być postrzegany jako system zamknięty, w którym komunikacja pomiędzy zadaniami odbywa się za pomocą i przy udziale koordynatora (aranżera) działającego zgodnie z grafem zadań systemu, a zadania odpowiadają funkcjom koordynatora.

D.Grela, K.Sapiecha, Error Injector for business processes orchestrated with the help of BPEL, International Conference On Computer Science - Research and Applications (IBIZA 2009), 2009

D.Grela, K.Sapiecha, J.Strug, How validation can help in testing business processes orchestrating web services, International Conference On Computer Science - Research and Applications (IBIZA 2012), Annales UMCS - Informatica, Volume 13, Number 1/2013, pp.23-35

Validation and testing are important in developing correct and fault free SOA-based systems. BPEL is a high level language that makes it possible to implement business processes as an orchestration of web services. In general, the testing requires much more test scenarios than the validation. However, in the case of BPEL processes, which have very simple and well structured implementation, test scenarios limited to the validation may also be efficient. The paper describes an experiment that aims at answering a question whether or not the validation test scenarios are also adequate for testing an implementation of BPEL processes. The experiment employs a Software Fault Injector for BPEL Processes that is able to inject faults when the test scenarios are running. The results of the experiment seem very promising. Hence, it seems that validation tests might give a strong support for testing.

D.Grela, K.Sapiecha, J.Strug, An application of software fault injection for assessment of quality of test sets for business processes orchestrating web-services, Proceedings of the 8^th International Conference On Evaluation of Novel Approaches to Software Engineering (ENASE 2013), pp.56-62

The paper presents an experiment of the application of software fault injection to assess quality of test sets for business processes orchestrating web-services. The mutation testing, usually used to this end, suffers from high computational costs of generating and running mutants. In contrast to mutation testing, faults injection can be performed at a run-time. Run-time changes are introduced by a Software Fault Injector for BPEL Processes (SFIBP). SFIBP is implemented as a special service that manipulates invocations of web-services and values of their internal variables. As for time requirements, the experiment proved high superiority of the application of the SFIBP over the mutation testing.

D.Grela, K.Sapiecha, J.Strug, A Fault Injection Based Approach to Assessment of Quality of Test Sets for BPEL Processes, Evaluation of Novel Approaches to Software Engineering Communications in Computer and Information Science, Volume 417, Springer, 2013, pp.81-93

Mutation testing is an effective technique for assessing a quality of test sets for software systems, but it suffers from high computational costs of generating and executing a large number of mutants. In the domain of BPEL processes each mutant needs to be deployed before it can be executed, thus the cost of processing mutants increases further. In contrast to mutation testing, fault injection is able to inject faults directly into the original process what reduces the redeployment requirement. The paper presents an experiment of the application of software fault injection to assess quality of test sets for BPEL processes. Faults are introduced by a Software Fault Injector for BPEL Processes (SFIBP). SFIBP simulates effects of the faults by modifying invocations of web-services and their internal variables. The experiment proved high superiority of the application of the SFIBP over the mutation testing, especially in the case of time requirements.

K.Kiełkowicz, D.Grela, Modified Bat Algorithm for Nonlinear Optimization, International Journal of Computer Science and Network Security (IJCSNS), Volume 16, Number 10, 2016, pp.46-50

Bat Algorithm is recently proposed bio-inspired metaheuristics method for solving hard optimization tasks. It mimics behavior of bats hunting for their prey. The paper introduces some modification to Bat Algorithm. Presented modification changes exploration process as well as introduce different scheme of acceptance of a newly founded solutions. Effects of introduced modifications are tested on standard benchmark functions. The influence of a number of bats used in optimization process is also taken into account.

K.Kiełkowicz, D.Grela, FLC control for tuning exploration phase in bio-inspired metaheuristic, International Conference On Computer Science - Research and Applications (IBIZA 2017), Annales UMCS - Informatica, Volume 16, Number 2/2016, pp.32-38

Growing popularity of the Bat Algorithm has encouraged researchers to focus their work on its further improvements. Most work has been done within the area of hybridization of Bat Algorithm with other metaheuristics or local search methods. Unfortunately, most of these modifications not only improves the quality of obtained solutions, but also increases the number of control parameters that are needed to be set in order to obtain solutions of expected quality. This makes such solutions quite impractical. What more, there is no clear indication what these parameters do in term of a search process. In this paper authors are trying to incorporate Mamdani type Fuzzy Logic Controller (FLC) to tackle some of these mentioned shortcomings by using the FLC to control the exploration phase of a bio-inspired metaheuristic. FLC also allows us to incorporate expert knowledge about the problem at hand and define expected behaviors of system – here process of searching in multidimensional search space by modeling the process of bats hunting for their prey.