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aysu can

Middle East Technical University, Informatics Institute, Faculty Member

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Mikael Lindvall

Fraunhofer

Middle East Technical University

Université du Québec à Chicoutimi

University of Oxford

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Papers by aysu can

Design for verification for concurrent and distributed programs

Design for Verification for Concurrent and Distributed Programs by Aysu Betin-Can In this dissert... more Design for Verification for Concurrent and Distributed Programs by Aysu Betin-Can In this dissertation we present a design for verification (DFV) approach that embeds intentions of developers into software and makes software systems amenable to automated verification; hence, making the automated verification techniques scalable to large systems. In this DFV approach, we use 1) behavioral interfaces that isolate the behavior and enable modular verification, 2) an assume-guarantee style verification strategy that separates verification of the behavior from the verification of the conformance to the interface specifications, 3) a general model checking technique for interface verification, and 4) domain specific and specialized verification techniques for behavior verification. We realize our DFV approach for concurrent programming by introducing the concurrency controller pattern. We aim to eliminate synchronization errors in concurrent Java programs. We use the Action Language Verifier to verify the concurrency controller behaviors by an automated translation from their Java implementations. We have applied this framework to two software systems: a concurrent text editor and a safety critical air traffic control software called TSAFE. To demonstrate the applicability of our DFV approach to another application domain, we introduce the peer controller pattern for asynchronously communicating viii web services. Our goal is both to analyze properties of interactions among the participating peers and to validate the conformance of peer implementations to their behavioral specifications. We use the SPIN model checker to verify the interaction properties. We adapt synchronizability analysis to enable behavior verification with respect to unbounded asynchronous communication queues. We extend this approach with an hierarchical interface model for compact representation of peer interfaces. We use the Java PathFinder for interface verification in both application domains. We present techniques for thread isolation which improve the efficiency of interface verification.

Playtesting: What is Beyond Personas

ArXiv, 2021

Playtesting is an essential step in the game design process. Game designers use the feedback from... more Playtesting is an essential step in the game design process. Game designers use the feedback from playtests to refine their design. Game designers may employ procedural personas to automate the playtesting process. In this paper, we present two approaches to improve automated playtesting. First, we propose a goal-based persona model, which we call developing persona— developing persona proposes a dynamic persona model, whereas the current persona models are static. Game designers can use the developing persona to model the changes that a player undergoes while playing a game. Additionally, a human playtester knows which paths she has tested before, and during the consequent tests, she may test different paths. However, RL agents disregard the previously generated trajectories. We propose a novel methodology that helps Reinforcement Learning (RL) agents to generate distinct trajectories than the previous trajectories. We refer to this methodology as Alternative Path Finder (APF). We ...

Türkiye'deki Yazılım Test Uygulamaları Anketi

Bağlam: Yazılım testi, yazılım geliştirme yaşam döngüsünde önemli bir faaliyettir. Her bir yazılı... more Bağlam: Yazılım testi, yazılım geliştirme yaşam döngüsünde önemli bir faaliyettir. Her bir yazılım takımı ve şirketinde gerçekleştirilen yazılım test uygulamalarının türleri ve olgunlukları geniş bir yelpazeye sahiptir. Bu yelpazeyi oluşturan test uygulamalarının türleri hakkında üst seviye bir bakış açısı betimlemek için değişik büyüklük ve bölgelerde (örneğin, Kanada, İsveç, ve Finlandiya) çeşitli anketler gerçekleştirilmiştir. Oldukça aktif olan Türkiye yazılım endüstrisinde de bu uygulamaların durumunu karakterize etmek ve anlamak önem taşımaktadır. Amaç: Amacımız, Türk yazılım endüstrisindeki test uygulama türlerine üst seviye bir bakış açısını karakterize etmek ve kavrayabilmektir. Bu çalışmada da test uygulamalarının özellikle şu açıları ile ilgilenmekteyiz: test türleri/seviyeleri, test teknikleri, test otomasyonu ve test araçları, test ölçütleri, test yönetimi, ve aynı zamanda Türk test mühendislerinin karşılaştıkları zorluklar. Yöntem: Yukarıda amaca ulaşmak için, Kanada bağlamındaki geçmiş deneyimimizi ve Software Engineering Body of Knowledge (SWEBOK)'ın kullanımını temel alan, 9'u yazılım testine odaklı 54 soruluk çevrimiçi bir anketi sistematik olarak tasarladık. Ankete, Türk yazılım endüstrisinden 163 yazılım mühendisi katıldı. Bu bildiride, yazılım testine odaklanan soruların sonuçlarını raporluyor ve sentezliyoruz. Mümkün olduğu ölçüde, anketimizin eğilim ve sonuçlarını Turkish Testing Board tarafından 2013'te gerçekleştirilen yeni bir anketin sonuçları ve Kanada yazılım endüstrisinde 2010'da gerçekleştirilen bir diğer benzer anket ile karşılaştırıyoruz. Bulgular: Anket sonuçları Türkiye'deki yazılım test uygulamaları hakkında önemli ve ilginç bulguları ortaya koymaktadır. Bulgular arasında şunlar yer almaktadır: (1) İşlevsel (fonksiyonel)/sistem testi, Kullanıcı kabul testi, ve Entegrasyon testi en geniş kullanılan üç test yaklaşımıdır. En az kullanılan teknik ise Stres testidir. (2) Türk testçilerinin %10'undan daha azı formal test durumu tasarım yaklaşımlarından birini kullanırken, Kanada'da bu oran %15 ve %27 arası olarak biraz daha iyi durumdadır. (3) hem Kanada'da hem de Türkiye'de, manuel ve otomatik test yaklaşımları için genel olarak geniş bir yelpaze mevcuttur. Bu durum, farklı katılımcıların birbirlerinden çok farklı uygulamalara sahip olduğunu göstermektedir. Örnek olarak, bazıları otomatik testi yoğun olarak uygularken, diğerleri manuel testi tercih etmektedir. (4) Genel olarak Türk yazılım endüstrisinde kod kapsama ölçütlerinin popülerliği düşüktür. (5) Türkiye'de

Web Uygulamalarında Dolaşım ve Erişim Kontrolü Hatalarının Tespiti ve Yeniden Canlandırılması

Özet. Bu çalışmada, dinamik web uygulamalarındaki dolaşım ve erişim hatalarına yol açan senaryola... more Özet. Bu çalışmada, dinamik web uygulamalarındaki dolaşım ve erişim hatalarına yol açan senaryoların tespiti ve otomatik olarak canlandırılması için bir araç sunulmaktadır. Sunulan yöntemde ilk olarak verilen web uygulamasının modeli, AJAX tabanlı web uygulamalarını analiz edebilen, web crawler araçları yardımıyla çıkartılmaktadır. Daha sonra, model, web crawler’a olan bağımlılığı azaltmak ve kullanıcılara çıkartılan modeller üzerinde değişiklik yapma imkanı vermek için oluşturulan ara modelleme diline çevrilmektedir. Ardından geliştirilen araç yardımıyla, model denetleme diline çevrilen modele denetlenmesi istenen özellikler kullanıcı tarafından tanımlanmaktadır. Son olarak, model denetleme aracının ürettiği karşı örnekler web tarayıcısı üzerinde canlandırılmaktadır. Bu özellikler ile model denetleme tekniğinin uygulanması ve çıktılarının herhangi bir geçmiş deneyim gerekmeden anlaşılabilmesi sağlanmaktadır. Aracın kullanılabilirliğini ölçmek için bir kullanıcı çalışması yürütülmüş...

Implications of Blockchain Technology in the Health Domain

Transactions on Computational Science and Computational Intelligence

Blockchains are tamper-evident and tamper-resistant digital ledgers. Due to their distributed and... more Blockchains are tamper-evident and tamper-resistant digital ledgers. Due to their distributed and shared nature, and their cryptographic functions, blockchains are resilient to alterations. They provide a trustworthy environment for the data stored in the ledgers. However, each new technology brings its own challenges along with the opportunities. Our minds are still busy with the question of “how could blockchain technology potentially benefit us?” In this paper, we approach to this question from the health domain perspective. Based on a systematic literature review, we discuss to what extent blockchain could provide solutions for the challenges inherited in the health domain and if blockchain technology introduces new challenges for development of health applications. The review included 27 publications which share experiences of practitioners from 2016 to 2020.

Detecting Execution and HTML Errors in ASP.NET Web Applications

Proceedings of the 6th International Conference on Software and Database Technologies, 2011

Dynamic web applications are becoming widespread nearly in every area. ASP.NET is one of the popu... more Dynamic web applications are becoming widespread nearly in every area. ASP.NET is one of the popular development technologies in this domain. The errors in these web applications can reduce the credibility of the site and cause possible loss of a number of clients. Therefore, testing these applications becomes significant. We present an automated tool to test ASP.NET web applications against execution errors and HTML errors that cause displaying inaccurate and incomplete information. Our tool, called Mamoste, adapts concolic testing technique which interleaves concrete and symbolic execution to generate test inputs dynamically. Mamoste also considers page events as inputs which cannot be handled with concolic testing. We have performed experiments on a subset of a heavily used ASP.NET application of a government office. We have found 366 HTML errors and a faulty component which is used almost every page in this application. In addition, Mamoste discovered that a common user control is misused in several dynamically generated pages. * This work is supported by STRATEK (www. stratek.com.tr) and TÜBİTAK (www.tubitak.gov.tr) 172 Erdal Özkınacı M. and Betin Can A..

Verifiable concurrent programming using concurrency controllers

Proceedings. 19th International Conference on Automated Software Engineering, 2004., 2004

We present a framework for verifiable concurrent programming in Java based on a design pattern fo... more We present a framework for verifiable concurrent programming in Java based on a design pattern for concurrency controllers. Using this pattern, a programmer can write concurrency controller classes defining a synchronization policy by specifying a set of guarded commands and without using any of the error-prone synchronization primitives of Java. We present a modular verification approach that exploits the modularity of the proposed pattern, i.e., decoupling of the controller behavior from the threads that use the controller. To verify the controller behavior (behavior verification) we use symbolic and infinite state model checking techniques, which enable verification of controllers with parameterized constants, unbounded variables and arbitrary number of user threads. To verify that the threads use a controller in the specified manner (interface verification) we use explicit state model checking techniques, which allow verification of arbitrary thread implementations without any restrictions. We show that the correctness of the user threads can be verified using the concurrency controller interfaces as stubs, which improves the efficiency of the interface verification significantly. We also show that the concurrency controllers can be automatically optimized using the specific notification pattern. We demonstrate the effectiveness of our approach on a Concurrent Editor implementation which consists of 2800 lines of Java code with remote procedure calls and complex synchronization constraints.

Verifiable Web services with hierarchical interfaces

IEEE International Conference on Web Services (ICWS'05), 2005

We propose an Hierarchical State Machine (HSM) model for specifying behavioral interfaces of peer... more We propose an Hierarchical State Machine (HSM) model for specifying behavioral interfaces of peers participating in a composite web service. We integrate the HSM model to a design pattern which is supported by a modular verification technique that can 1) statically analyze the properties about global interactions of a composite web service and 2) check the conformance of the Java implementations of the participant peers to their interfaces. We extend the synchronizability analysis to HSMs to efficiently identify composite web services whose global interactions can be analyzed with respect to unbounded queues using finite state model checkers. We also discuss automated translation of behavioral interfaces specified as HSMs to BPEL specifications to be published and used by other services.

A systematic mapping study of web application testing

Information and Software Technology, 2013

Context: The Web has had a significant impact on all aspects of our society. As our society relie... more Context: The Web has had a significant impact on all aspects of our society. As our society relies more and more on the Web, the dependability of web applications has become increasingly important. To make these applications more dependable, for the past decade researchers have proposed various techniques for testing web-based software applications. Our literature search for related studies retrieved 147 papers in the area of web application testing, which have appeared between 2000 and 2011. Objective: As this research area matures and the number of related papers increases, it is important to systematically identify, analyze, and classify the publications and provide an overview of the trends in this specialized field. Method: We review and structure the body of knowledge related to web application testing through a systematic mapping (SM) study. As part of this study, we pose two sets of research questions, define selection and exclusion criteria, and systematically develop and refine a classification schema. In addition, we conduct a bibliometrics analysis of the papers included in our study. Results: Our study includes a set of 79 papers (from the 147 retrieved papers) published in the area of web application testing between 2000 and 2011. We present the results of our systematic mapping study. Our mapping data is available through a publicly-accessible repository. We derive the observed trends, for instance, in terms of types of papers, sources of information to derive test cases, and types of evaluations used in papers. We also report the demographics and bibliometrics trends in this domain, including top-cited papers, active countries and researchers, and top venues in this research area. Conclusion: We discuss the emerging trends in web application testing, and discuss the implications for researchers and practitioners in this area. The results of our systematic mapping can help researchers to obtain an overview of existing web application testing approaches and indentify areas in the field that require more attention from the research community.

Interface-Based Specification and Verification of Concurrency Controllers

Electronic Notes in Theoretical Computer Science, 2003

Design for verification for asynchronously communicating Web services

Proceedings of the 14th international conference on World Wide Web - WWW '05, 2005

We present a design for verification approach to developing reliable web services. We focus on co... more We present a design for verification approach to developing reliable web services. We focus on composite web services which consist of asynchronously communicating peers. Our goal is to automatically verify properties of interactions among such peers. We propose a design pattern that eases the development of such web services and enables a modular, assume-guarantee style verification strategy. In the proposed design pattern, each peer is associated with a behavioral interface description which specifies how that peer will interact with other peers. Using these peer interfaces we automatically generate BPEL specifications to publish for interoperability. Assuming that the participating peers behave according to their interfaces, we verify safety and liveness properties about the global behavior of the composite web service during behavior verification. During interface verification, we check that each peer implementation conforms to its interface. Using the modularity in the proposed design pattern, we are able to perform the interface verification of each peer and the behavior verification as separate steps. Our experiments show that, using this modular approach, one can automatically and efficiently verify web service implementations.

Code-carrying theories

This paper is both a position paper on a particular approach in program correctness, and also a c... more This paper is both a position paper on a particular approach in program correctness, and also a contribution to this area. The approach entails the generation of programs (code) from the executable content of logical theories. This capability already exists within the main theorem provers like Coq, Isabelle and ACL2 and PVS. Here we will focus on issues portraying the use of this methodology, rather than the underlying theory. We illustrate the power of the approach within PVS via two case studies (on unification and compression) that lead to actual running code. We also demonstrate its flexibility by extending the program generation capabilities. This paper fits in a line of ongoing integration of programming and proving.

Software test-code engineering: A systematic mapping

Information and Software Technology, 2015

Context: As a result of automated software testing, large amounts of software test code (script) ... more Context: As a result of automated software testing, large amounts of software test code (script) are usually developed by software teams. Automated test scripts provide many benefits, such as repeatable, predictable, and efficient test executions. However, just like any software development activity, development of test scripts is tedious and error prone. We refer, in this study, to all activities that should be conducted during the entire lifecycle of test-code as Software Test-Code Engineering (STCE). Objective: As the STCE research area has matured and the number of related studies has increased, it is important to systematically categorize the current state-of-the-art and to provide an overview of the trends in this field. Such summarized and categorized results provide many benefits to the broader community. For example, they are valuable resources for new researchers (e.g., PhD students) aiming to conduct additional secondary studies. Method: In this work, we systematically classify the body of knowledge related to STCE through a systematic mapping (SM) study. As part of this study, we pose a set of research questions, define selection and exclusion criteria, and systematically develop and refine a systematic map. Results: Our study pool includes a set of 60 studies published in the area of STCE between 1999 and 2012. Our mapping data is available through an online publicly-accessible repository. We derive the trends for various aspects of STCE. Among our results are the following: (1) There is an acceptable mix of papers with respect to different contribution facets in the field of STCE and the top two leading facets are tool (68%) and method (65%). The studies that presented new processes, however, had a low rate (3%), which denotes the need for more process-related studies in this area. (2) Results of investigation about research facet of studies and comparing our result to other SM studies shows that, similar to other fields in software engineering, STCE is moving towards more rigorous validation approaches. (3) A good mixture of STCE activities has been presented in the primary studies. Among them, the two leading activities are quality assessment and co-maintenance of test-code with production code. The highest growth rate for co-maintenance activities in recent years shows the importance and challenges involved in this activity.

Modular verification of synchronization with reentrant locks

Eighth ACM/IEEE International Conference on Formal Methods and Models for Codesign (MEMOCODE 2010), 2010

... Fang Yu Department of Computer Science University of California Santa Barbara, CA, USA yuf@cs... more

Toward effective medical search engines

2010 5th International Symposium on Health Informatics and Bioinformatics, 2010

ABSTRACT In this paper, we present a domain specific search engine that relies on extracting the ... more

A model based on multi-features to enhance healthcare and medical document retrieval

Informatics for Health and Social Care, 2011

A major problem in biomedical informatics is the contextual retrieval and ranking of medical and ... more A major problem in biomedical informatics is the contextual retrieval and ranking of medical and healthcare information. In this article, we present a model for extracting semantic relations among medical and clinical documents. The purpose is to maximise contextual retrieval and ranking performance with minimum input from users. We developed and evaluated a medical search engine that relies on a multi-features similarity model. The indexed documents are represented as a network that reflects the semantic relations among documents to assess topical rankings. The evaluation measurements include the following: recall, precision and R-precision. We used OHSUMED collection to evaluate our work with runs submitted to TREC-9. We provide a comparison of the top five runs that achieved the highest average precision scores. In addition, we used questionnaire-based evaluation to measure the effectiveness of the ranking task. The results indicated that the proposed model achieved a higher average precision in comparison with top-scored runs submitted to TREC-9; the improvement of our model over other methods is statistically significant (p-value &amp;amp;amp;amp;lt;0.0001). Furthermore, a questionnaire-based experiment showed that the proposed model performed quite well in ranking retrieved documents according to their topics.

Eliminating synchronization faults in air traffic control software via design for verification with concurrency controllers

Automated Software Engineering, 2007

... Eliminating synchronization faults in air traffic control software via design for verificatio... more

Design for verification for concurrent and distributed programs

Design for Verification for Concurrent and Distributed Programs by Aysu Betin-Can In this dissert... more Design for Verification for Concurrent and Distributed Programs by Aysu Betin-Can In this dissertation we present a design for verification (DFV) approach that embeds intentions of developers into software and makes software systems amenable to automated verification; hence, making the automated verification techniques scalable to large systems. In this DFV approach, we use 1) behavioral interfaces that isolate the behavior and enable modular verification, 2) an assume-guarantee style verification strategy that separates verification of the behavior from the verification of the conformance to the interface specifications, 3) a general model checking technique for interface verification, and 4) domain specific and specialized verification techniques for behavior verification. We realize our DFV approach for concurrent programming by introducing the concurrency controller pattern. We aim to eliminate synchronization errors in concurrent Java programs. We use the Action Language Verifier to verify the concurrency controller behaviors by an automated translation from their Java implementations. We have applied this framework to two software systems: a concurrent text editor and a safety critical air traffic control software called TSAFE. To demonstrate the applicability of our DFV approach to another application domain, we introduce the peer controller pattern for asynchronously communicating viii web services. Our goal is both to analyze properties of interactions among the participating peers and to validate the conformance of peer implementations to their behavioral specifications. We use the SPIN model checker to verify the interaction properties. We adapt synchronizability analysis to enable behavior verification with respect to unbounded asynchronous communication queues. We extend this approach with an hierarchical interface model for compact representation of peer interfaces. We use the Java PathFinder for interface verification in both application domains. We present techniques for thread isolation which improve the efficiency of interface verification.

Playtesting: What is Beyond Personas

ArXiv, 2021

Playtesting is an essential step in the game design process. Game designers use the feedback from... more Playtesting is an essential step in the game design process. Game designers use the feedback from playtests to refine their design. Game designers may employ procedural personas to automate the playtesting process. In this paper, we present two approaches to improve automated playtesting. First, we propose a goal-based persona model, which we call developing persona— developing persona proposes a dynamic persona model, whereas the current persona models are static. Game designers can use the developing persona to model the changes that a player undergoes while playing a game. Additionally, a human playtester knows which paths she has tested before, and during the consequent tests, she may test different paths. However, RL agents disregard the previously generated trajectories. We propose a novel methodology that helps Reinforcement Learning (RL) agents to generate distinct trajectories than the previous trajectories. We refer to this methodology as Alternative Path Finder (APF). We ...

Türkiye'deki Yazılım Test Uygulamaları Anketi

Bağlam: Yazılım testi, yazılım geliştirme yaşam döngüsünde önemli bir faaliyettir. Her bir yazılı... more Bağlam: Yazılım testi, yazılım geliştirme yaşam döngüsünde önemli bir faaliyettir. Her bir yazılım takımı ve şirketinde gerçekleştirilen yazılım test uygulamalarının türleri ve olgunlukları geniş bir yelpazeye sahiptir. Bu yelpazeyi oluşturan test uygulamalarının türleri hakkında üst seviye bir bakış açısı betimlemek için değişik büyüklük ve bölgelerde (örneğin, Kanada, İsveç, ve Finlandiya) çeşitli anketler gerçekleştirilmiştir. Oldukça aktif olan Türkiye yazılım endüstrisinde de bu uygulamaların durumunu karakterize etmek ve anlamak önem taşımaktadır. Amaç: Amacımız, Türk yazılım endüstrisindeki test uygulama türlerine üst seviye bir bakış açısını karakterize etmek ve kavrayabilmektir. Bu çalışmada da test uygulamalarının özellikle şu açıları ile ilgilenmekteyiz: test türleri/seviyeleri, test teknikleri, test otomasyonu ve test araçları, test ölçütleri, test yönetimi, ve aynı zamanda Türk test mühendislerinin karşılaştıkları zorluklar. Yöntem: Yukarıda amaca ulaşmak için, Kanada bağlamındaki geçmiş deneyimimizi ve Software Engineering Body of Knowledge (SWEBOK)'ın kullanımını temel alan, 9'u yazılım testine odaklı 54 soruluk çevrimiçi bir anketi sistematik olarak tasarladık. Ankete, Türk yazılım endüstrisinden 163 yazılım mühendisi katıldı. Bu bildiride, yazılım testine odaklanan soruların sonuçlarını raporluyor ve sentezliyoruz. Mümkün olduğu ölçüde, anketimizin eğilim ve sonuçlarını Turkish Testing Board tarafından 2013'te gerçekleştirilen yeni bir anketin sonuçları ve Kanada yazılım endüstrisinde 2010'da gerçekleştirilen bir diğer benzer anket ile karşılaştırıyoruz. Bulgular: Anket sonuçları Türkiye'deki yazılım test uygulamaları hakkında önemli ve ilginç bulguları ortaya koymaktadır. Bulgular arasında şunlar yer almaktadır: (1) İşlevsel (fonksiyonel)/sistem testi, Kullanıcı kabul testi, ve Entegrasyon testi en geniş kullanılan üç test yaklaşımıdır. En az kullanılan teknik ise Stres testidir. (2) Türk testçilerinin %10'undan daha azı formal test durumu tasarım yaklaşımlarından birini kullanırken, Kanada'da bu oran %15 ve %27 arası olarak biraz daha iyi durumdadır. (3) hem Kanada'da hem de Türkiye'de, manuel ve otomatik test yaklaşımları için genel olarak geniş bir yelpaze mevcuttur. Bu durum, farklı katılımcıların birbirlerinden çok farklı uygulamalara sahip olduğunu göstermektedir. Örnek olarak, bazıları otomatik testi yoğun olarak uygularken, diğerleri manuel testi tercih etmektedir. (4) Genel olarak Türk yazılım endüstrisinde kod kapsama ölçütlerinin popülerliği düşüktür. (5) Türkiye'de

Web Uygulamalarında Dolaşım ve Erişim Kontrolü Hatalarının Tespiti ve Yeniden Canlandırılması

Özet. Bu çalışmada, dinamik web uygulamalarındaki dolaşım ve erişim hatalarına yol açan senaryola... more Özet. Bu çalışmada, dinamik web uygulamalarındaki dolaşım ve erişim hatalarına yol açan senaryoların tespiti ve otomatik olarak canlandırılması için bir araç sunulmaktadır. Sunulan yöntemde ilk olarak verilen web uygulamasının modeli, AJAX tabanlı web uygulamalarını analiz edebilen, web crawler araçları yardımıyla çıkartılmaktadır. Daha sonra, model, web crawler’a olan bağımlılığı azaltmak ve kullanıcılara çıkartılan modeller üzerinde değişiklik yapma imkanı vermek için oluşturulan ara modelleme diline çevrilmektedir. Ardından geliştirilen araç yardımıyla, model denetleme diline çevrilen modele denetlenmesi istenen özellikler kullanıcı tarafından tanımlanmaktadır. Son olarak, model denetleme aracının ürettiği karşı örnekler web tarayıcısı üzerinde canlandırılmaktadır. Bu özellikler ile model denetleme tekniğinin uygulanması ve çıktılarının herhangi bir geçmiş deneyim gerekmeden anlaşılabilmesi sağlanmaktadır. Aracın kullanılabilirliğini ölçmek için bir kullanıcı çalışması yürütülmüş...

Implications of Blockchain Technology in the Health Domain

Transactions on Computational Science and Computational Intelligence

Blockchains are tamper-evident and tamper-resistant digital ledgers. Due to their distributed and... more Blockchains are tamper-evident and tamper-resistant digital ledgers. Due to their distributed and shared nature, and their cryptographic functions, blockchains are resilient to alterations. They provide a trustworthy environment for the data stored in the ledgers. However, each new technology brings its own challenges along with the opportunities. Our minds are still busy with the question of “how could blockchain technology potentially benefit us?” In this paper, we approach to this question from the health domain perspective. Based on a systematic literature review, we discuss to what extent blockchain could provide solutions for the challenges inherited in the health domain and if blockchain technology introduces new challenges for development of health applications. The review included 27 publications which share experiences of practitioners from 2016 to 2020.

Detecting Execution and HTML Errors in ASP.NET Web Applications

Proceedings of the 6th International Conference on Software and Database Technologies, 2011

Dynamic web applications are becoming widespread nearly in every area. ASP.NET is one of the popu... more Dynamic web applications are becoming widespread nearly in every area. ASP.NET is one of the popular development technologies in this domain. The errors in these web applications can reduce the credibility of the site and cause possible loss of a number of clients. Therefore, testing these applications becomes significant. We present an automated tool to test ASP.NET web applications against execution errors and HTML errors that cause displaying inaccurate and incomplete information. Our tool, called Mamoste, adapts concolic testing technique which interleaves concrete and symbolic execution to generate test inputs dynamically. Mamoste also considers page events as inputs which cannot be handled with concolic testing. We have performed experiments on a subset of a heavily used ASP.NET application of a government office. We have found 366 HTML errors and a faulty component which is used almost every page in this application. In addition, Mamoste discovered that a common user control is misused in several dynamically generated pages. * This work is supported by STRATEK (www. stratek.com.tr) and TÜBİTAK (www.tubitak.gov.tr) 172 Erdal Özkınacı M. and Betin Can A..

Verifiable concurrent programming using concurrency controllers

Proceedings. 19th International Conference on Automated Software Engineering, 2004., 2004

We present a framework for verifiable concurrent programming in Java based on a design pattern fo... more We present a framework for verifiable concurrent programming in Java based on a design pattern for concurrency controllers. Using this pattern, a programmer can write concurrency controller classes defining a synchronization policy by specifying a set of guarded commands and without using any of the error-prone synchronization primitives of Java. We present a modular verification approach that exploits the modularity of the proposed pattern, i.e., decoupling of the controller behavior from the threads that use the controller. To verify the controller behavior (behavior verification) we use symbolic and infinite state model checking techniques, which enable verification of controllers with parameterized constants, unbounded variables and arbitrary number of user threads. To verify that the threads use a controller in the specified manner (interface verification) we use explicit state model checking techniques, which allow verification of arbitrary thread implementations without any restrictions. We show that the correctness of the user threads can be verified using the concurrency controller interfaces as stubs, which improves the efficiency of the interface verification significantly. We also show that the concurrency controllers can be automatically optimized using the specific notification pattern. We demonstrate the effectiveness of our approach on a Concurrent Editor implementation which consists of 2800 lines of Java code with remote procedure calls and complex synchronization constraints.

Verifiable Web services with hierarchical interfaces

IEEE International Conference on Web Services (ICWS'05), 2005

We propose an Hierarchical State Machine (HSM) model for specifying behavioral interfaces of peer... more We propose an Hierarchical State Machine (HSM) model for specifying behavioral interfaces of peers participating in a composite web service. We integrate the HSM model to a design pattern which is supported by a modular verification technique that can 1) statically analyze the properties about global interactions of a composite web service and 2) check the conformance of the Java implementations of the participant peers to their interfaces. We extend the synchronizability analysis to HSMs to efficiently identify composite web services whose global interactions can be analyzed with respect to unbounded queues using finite state model checkers. We also discuss automated translation of behavioral interfaces specified as HSMs to BPEL specifications to be published and used by other services.

A systematic mapping study of web application testing

Information and Software Technology, 2013

Context: The Web has had a significant impact on all aspects of our society. As our society relie... more Context: The Web has had a significant impact on all aspects of our society. As our society relies more and more on the Web, the dependability of web applications has become increasingly important. To make these applications more dependable, for the past decade researchers have proposed various techniques for testing web-based software applications. Our literature search for related studies retrieved 147 papers in the area of web application testing, which have appeared between 2000 and 2011. Objective: As this research area matures and the number of related papers increases, it is important to systematically identify, analyze, and classify the publications and provide an overview of the trends in this specialized field. Method: We review and structure the body of knowledge related to web application testing through a systematic mapping (SM) study. As part of this study, we pose two sets of research questions, define selection and exclusion criteria, and systematically develop and refine a classification schema. In addition, we conduct a bibliometrics analysis of the papers included in our study. Results: Our study includes a set of 79 papers (from the 147 retrieved papers) published in the area of web application testing between 2000 and 2011. We present the results of our systematic mapping study. Our mapping data is available through a publicly-accessible repository. We derive the observed trends, for instance, in terms of types of papers, sources of information to derive test cases, and types of evaluations used in papers. We also report the demographics and bibliometrics trends in this domain, including top-cited papers, active countries and researchers, and top venues in this research area. Conclusion: We discuss the emerging trends in web application testing, and discuss the implications for researchers and practitioners in this area. The results of our systematic mapping can help researchers to obtain an overview of existing web application testing approaches and indentify areas in the field that require more attention from the research community.

Interface-Based Specification and Verification of Concurrency Controllers

Electronic Notes in Theoretical Computer Science, 2003

Design for verification for asynchronously communicating Web services

Proceedings of the 14th international conference on World Wide Web - WWW '05, 2005

We present a design for verification approach to developing reliable web services. We focus on co... more We present a design for verification approach to developing reliable web services. We focus on composite web services which consist of asynchronously communicating peers. Our goal is to automatically verify properties of interactions among such peers. We propose a design pattern that eases the development of such web services and enables a modular, assume-guarantee style verification strategy. In the proposed design pattern, each peer is associated with a behavioral interface description which specifies how that peer will interact with other peers. Using these peer interfaces we automatically generate BPEL specifications to publish for interoperability. Assuming that the participating peers behave according to their interfaces, we verify safety and liveness properties about the global behavior of the composite web service during behavior verification. During interface verification, we check that each peer implementation conforms to its interface. Using the modularity in the proposed design pattern, we are able to perform the interface verification of each peer and the behavior verification as separate steps. Our experiments show that, using this modular approach, one can automatically and efficiently verify web service implementations.

Code-carrying theories

This paper is both a position paper on a particular approach in program correctness, and also a c... more This paper is both a position paper on a particular approach in program correctness, and also a contribution to this area. The approach entails the generation of programs (code) from the executable content of logical theories. This capability already exists within the main theorem provers like Coq, Isabelle and ACL2 and PVS. Here we will focus on issues portraying the use of this methodology, rather than the underlying theory. We illustrate the power of the approach within PVS via two case studies (on unification and compression) that lead to actual running code. We also demonstrate its flexibility by extending the program generation capabilities. This paper fits in a line of ongoing integration of programming and proving.

Software test-code engineering: A systematic mapping

Information and Software Technology, 2015

Context: As a result of automated software testing, large amounts of software test code (script) ... more Context: As a result of automated software testing, large amounts of software test code (script) are usually developed by software teams. Automated test scripts provide many benefits, such as repeatable, predictable, and efficient test executions. However, just like any software development activity, development of test scripts is tedious and error prone. We refer, in this study, to all activities that should be conducted during the entire lifecycle of test-code as Software Test-Code Engineering (STCE). Objective: As the STCE research area has matured and the number of related studies has increased, it is important to systematically categorize the current state-of-the-art and to provide an overview of the trends in this field. Such summarized and categorized results provide many benefits to the broader community. For example, they are valuable resources for new researchers (e.g., PhD students) aiming to conduct additional secondary studies. Method: In this work, we systematically classify the body of knowledge related to STCE through a systematic mapping (SM) study. As part of this study, we pose a set of research questions, define selection and exclusion criteria, and systematically develop and refine a systematic map. Results: Our study pool includes a set of 60 studies published in the area of STCE between 1999 and 2012. Our mapping data is available through an online publicly-accessible repository. We derive the trends for various aspects of STCE. Among our results are the following: (1) There is an acceptable mix of papers with respect to different contribution facets in the field of STCE and the top two leading facets are tool (68%) and method (65%). The studies that presented new processes, however, had a low rate (3%), which denotes the need for more process-related studies in this area. (2) Results of investigation about research facet of studies and comparing our result to other SM studies shows that, similar to other fields in software engineering, STCE is moving towards more rigorous validation approaches. (3) A good mixture of STCE activities has been presented in the primary studies. Among them, the two leading activities are quality assessment and co-maintenance of test-code with production code. The highest growth rate for co-maintenance activities in recent years shows the importance and challenges involved in this activity.

Modular verification of synchronization with reentrant locks

Eighth ACM/IEEE International Conference on Formal Methods and Models for Codesign (MEMOCODE 2010), 2010

... Fang Yu Department of Computer Science University of California Santa Barbara, CA, USA yuf@cs... more

Toward effective medical search engines

2010 5th International Symposium on Health Informatics and Bioinformatics, 2010

ABSTRACT In this paper, we present a domain specific search engine that relies on extracting the ... more

A model based on multi-features to enhance healthcare and medical document retrieval

Informatics for Health and Social Care, 2011

A major problem in biomedical informatics is the contextual retrieval and ranking of medical and ... more A major problem in biomedical informatics is the contextual retrieval and ranking of medical and healthcare information. In this article, we present a model for extracting semantic relations among medical and clinical documents. The purpose is to maximise contextual retrieval and ranking performance with minimum input from users. We developed and evaluated a medical search engine that relies on a multi-features similarity model. The indexed documents are represented as a network that reflects the semantic relations among documents to assess topical rankings. The evaluation measurements include the following: recall, precision and R-precision. We used OHSUMED collection to evaluate our work with runs submitted to TREC-9. We provide a comparison of the top five runs that achieved the highest average precision scores. In addition, we used questionnaire-based evaluation to measure the effectiveness of the ranking task. The results indicated that the proposed model achieved a higher average precision in comparison with top-scored runs submitted to TREC-9; the improvement of our model over other methods is statistically significant (p-value &amp;amp;amp;amp;lt;0.0001). Furthermore, a questionnaire-based experiment showed that the proposed model performed quite well in ranking retrieved documents according to their topics.

Eliminating synchronization faults in air traffic control software via design for verification with concurrency controllers

Automated Software Engineering, 2007

... Eliminating synchronization faults in air traffic control software via design for verificatio... more