A search-based technique for testing from extended finite state machine model

Extended finite state machines (EFSMs), and languages such as state-charts that are similar to EFSMs, are widely used to model state-based systems. When testing from an EFSM M it is common to aim to produce a set of test sequences (input sequences) that satisfies a test criterion that relates to the transition paths (TPs) of M that are executed by the test sequences. For example, we might require that the set of TPs triggered includes all of the transitions of M. One approach to generating such a set of test sequences is to split the problem into two stages: choosing a set of TPs that achieves the test criterion and then producing test sequences to trigger these TPs. However, the EFSM may contain infeasible TPs and the problem of generating a test sequence to trigger a given feasible TP (FTP) is generally uncomputable. In this paper we present a search-based approach that uses two techniques: (1) A TP fitness metric based on our previous work that estimates the feasibility of a given transition path; and (2) A fitness function to guide the search for a test sequence to trigger a given FTP. We evaluated our approach on five EFSMs: A simple in-flight safety system; a class II transport protocol; a lift system; an ATM; and the Inres initiator. In the experiments the proposed approach successfully tested approximately 96.75 % of the transitions and the proposed test sequence generation technique triggered all of the generated FTPs

Generating feasible transition paths for testing from an extended finite state machine (EFSM)

The problem of testing from an extended finite state machine (EFSM) can be expressed in terms of finding suitable paths through the EFSM and then deriving test data to follow the paths. A chosen path may be infeasible and so it is desirable to have methods that can direct the search for appropriate paths through the EFSM towards those that are likely to be feasible. However, generating feasible transition paths (FTPs) for model based testing is a challenging task and is an open research problem. This paper introduces a novel fitness metric that analyzes data flow dependence among the actions and conditions of the transitions in order to estimate the feasibility of a transition path. The proposed fitness metric is evaluated by being used in a genetic algorithm to guide the search for FTPs

A search-based approach for automatic test generation from extended finite state machine (EFSM)

The extended finite state machine is a powerful model that can capture almost all the aspects of a system. However, testing from an EFSM is yet a challenging task due to two main problems: path feasibility and path test data generation. Although optimization algorithms are efficient, their applications to EFSM testing have received very little attention. The aim of this paper is to develop a novel approach that utilizes optimization algorithms to test from EFSM models

Automatic generation of test sequences form EFSM models using evolutionary algorithms

Automated test data generation through evolutionary testing (ET) is a topic of interest to the software engineering community. While there are many ET-based techniques for automatically generating test data from code, the problem of generating test data from an extended finite state machine (EFSMs) is more complex and has received little attention. In this paper, we introduce a novel approach that addresses the problem of generating input test sequences that trigger given feasible paths in an EFSM model by employing an ET-based technique. The proposed approach expresses the problem as a search for input parameters to be applied to a set of functions to be called sequentially. In order to apply ET-based technique, a new fitness function is introduced to cope with the case when a test target involves calls to a set of transitions sequentially. We evaluate our approach empirically using five sets of randomly generated paths through two EFSM case studies: INRES and class 2 transport protocols. In the experiments, we apply two search techniques: a random and an ET-based which utilizes our new fitness function. Experimental results show that the proposed approach produces input test sequences that trigger all the feasible paths used with a success rate of 100%, however, the random technique failed in most cases with a success rate of 20.8%

A testability transformation approach for state-based programs

Search based testing approaches are efficient in test data generation; however they are likely to perform poorly when applied to programs with state variables. The problem arises when the target function includes guards that reference some of the program state variables whose values depend on previous function calls. Thus, merely considering the target function to derive test data is not sufficient. This paper introduces a testability transformation approach based on the analysis of control and data flow dependencies to bypass the state variable problem. It achieves this by eliminating state variables from guards and/ or determining which functions to call in order to satisfy guards with state variables. A number of experiments demonstrate the value of the proposed approach

Generating feasible transition paths for testing from an extended finite state machine (EFSM) with the counter problem

The extended finite state machine (EFSM) is a powerful approach for modeling state-based systems. However, testing from EFSMs is complicated by the existence of infeasible paths. One important problem is the existence of a transition with a guard that references a counter variable whose value depends on previous transitions. The presence of such transitions in paths often leads to infeasible paths. This paper proposes a novel approach to bypass the counter problem. The proposed approach is evaluated by being used in a genetic algorithm to guide the search for feasible transition paths (FTPs)

Application of Bacteriophages for Mycobacterial Infections, from Diagnosis to Treatment

Mycobacterium tuberculosis and other non-tuberculous mycobacteria are responsible for a variety of different infections affecting millions of patients worldwide. Their diagnosis is often problematic and delayed until late in the course of disease, requiring a high index of suspicion and the combined efforts of clinical and laboratory colleagues. Molecular methods, such as PCR platforms, are available, but expensive, and with limited sensitivity in the case of paucibacillary disease. Treatment of mycobacterial infections is also challenging, typically requiring months of multiple and combined antibiotics, with associated side effects and toxicities. The presence of innate and acquired drug resistance further complicates the picture, with dramatic cases without effective treatment options. Bacteriophages (viruses that infect bacteria) have been used for decades in Eastern Europe for the treatment of common bacterial infections, but there is limited clinical experience of their use in mycobacterial infections. More recently, bacteriophages’ clinical utility has been re-visited and their use has been successfully demonstrated both as diagnostic and treatment options. This review will focus specifically on how mycobacteriophages have been used recently in the diagnosis and treatment of different mycobacterial infections, as potential emerging technologies, and as an alternative treatment option

‘Devolution and Cultural Catch-Up: Decoupling England and its Literature from English Literature’

Robert McLiam Wilson’s 1989 novel Ripley Bogle uses an unreliable narrator to expose the differences – regional, linguistic and national – between communities Bogle, the protagonist, experiences in Cambridge and Northern Ireland. Bogle is an English Literature student and then drop-out whose rejection of canonical study is the rejection of Arnoldianism and a traditionally organist and imperialist discipline that reanimates the debate about civic values and literary culture. A similar device is used in Sebastian Faulks’s 2007 novel Engleby in which Mike Engleby abandons English Literature at University only to later become a journalist probing the political landscape and personalities of the 1980s and after. Embroiled in disappearance and death, Engleby’s psychological unpredictability enables a reading of Britain’s socio-political death. These interconnected novels stand either side of Britain’s devolutionary divide and, as a pair, are suggestive of England’s need to readdress its own literary culture in the face of devolution. They are also symptomatic of a wider cultural catch-up required within England after 1999. Where the other devolved nations have sought to advance new and challenging national literary concerns and forms distinct from the pan-British literary canon of the past (and its restrictive exclusion based on class, gender and race), England has only recently come to view its literary culture as national. However, this has provided a potential filled moment of redefinition that will help free England and its authors from the pan-British sensibility of imperial dominance. This chapter argues that such redefinition, and resistance to the canon, developed immediately before and dramatically after devolution is evident in Graham Swift’s Last Orders (1996) with its resistive yet civic working class community and in the representations of marginalised, disempowered sections of England’s population offered in Alan Kent’s Proper Job, Charlie Kurnow (2005), Stella Duffy’s The Room of Lost Things (2009) and Jim Crace’s All That Follows (2010). These authors seize the opportunity provided by devolution to re-examine England’s national identity and to probe its relation to political enfranchisement, civic responsibility and literary vitality as England culturally catches up with its own socio-political reality

Emerging Concepts for Pelvic Organ Prolapse Surgery: What is Cure?

The objective of this review is to discuss emerging concepts in pelvic organ prolapse, in particular, “What is cure?” In a post-trial data analysis of the CARE (Colpopexy and Urinary Reduction Efforts) trial, treatment success varied tremendously depending on the definition used (19.2%–97.2%). Definitions that included the absence of vaginal bulge symptoms had the strongest relationships with the patients’ assessment of overall improvement and treatment success. As demonstrated by this study, there are several challenges in defining cure in prolapse surgery. Additionally, the symptoms of prolapse are variable. The degree of prolapse does not correlate directly with symptoms. There are many surgical approaches to pelvic organ prolapse. Multiple ways to quantify prolapse are used. There is a lack of standardized definition of cure. The data on prolapse surgery outcomes are heterogeneous. The goal of surgical repair is to return the pelvic organs to their original anatomic positions. Ideally, we have four main goals: no anatomic prolapse, no functional symptoms, patient satisfaction, and the avoidance of complications. The impact of transvaginal mesh requires thoughtful investigation. The driving force should be patient symptoms in defining cure of prolapse

Pelvic organ prolapse symptoms in relation to POPQ, ordinal stages and ultrasound prolapse assessment

Adequate staging of pelvic organ prolapse is important in clinical practice and research. The ability of the POPQ, ordinal stages and ultrasound prolapse assessment were evaluated for their ability to discriminate between women with and without prolapse symptoms. The leading edge of the predominant compartment in the three assessment systems was used for the calculation of receiver operating characteristics curves. Two hundred and sixty five (265) consecutive women were evaluated. The area under the receiver operating characteristics curve for the three staging systems ranged from 0.715 to 0.783. POPQ staging and ordinal staging performed equally well in the prediction of prolapse symptoms (p = 0.780), and both performed better as compared with ultrasound prolapse assessment (p = 0.048 and p = 0.015, respectively). Prolapse staging can equally be performed by the POPQ and ordinal stages systems as far as the discrimination between women with and without prolapse symptoms is concerned. The ultrasound prolapse assessment does not perform better as compared with these two systems