An Analysis of the Current Program Slicing and Algorithmic Debugging Based Techniques

This thesis presents a classification of program slicing based techniques. The classification allows us to identify the differences between existing techniques, but it also allows us to predict new slicing techniques. The study identifies and compares the dimensions that influence current techniques.Silva Galiana, JF. (2008). An Analysis of the Current Program Slicing and Algorithmic Debugging Based Techniques. http://hdl.handle.net/10251/14300Archivo delegad

Optimal divide and query

Algorithmic debugging is a semi-automatic debugging technique that allows the programmer to precisely identify the location of bugs without the need to inspect the source code. The technique has been successfully adapted to all paradigms and mature implementations have been released for languages such as Haskell, Prolog or Java. During three decades, the algorithm introduced by Shapiro and later improved by Hirunkitti has been thought optimal. In this paper we first show that this algorithm is not optimal, and moreover, in some situations it is unable to find all possible solutions, thus it is incomplete. Then, we present a new version of the algorithm that is proven optimal, and we introduce some equations that allow the algorithm to identify all optimal solutions.This work has been partially supported by the Spanish Ministerio de Ciencia e Innovación under grant TIN2008-06622-C03-02 and by the Generalitat Valenciana under grant PROMETEO/2011/052.Insa Cabrera, D.; Silva Galiana, JF. (2011). Optimal divide and query. En Progress in Artificial Intelligence. Springer Verlag (Germany). 7026:224-238. https://doi.org/10.1007/978-3-642-24769-9_17S2242387026Braßel, B., Huch, F.: The Kiel Curry system KiCS. In: Proc of 17th International Conference on Applications of Declarative Programming and Knowledge Management (INAP 2007) and 21st Workshop on (Constraint) Logic Programming (WLP 2007), pp. 215–223. Technical Report 434, University of Würzburg (2007)Caballero, R.: A Declarative Debugger of Incorrect Answers for Constraint Functional-Logic Programs. In: Proc. of the 2005 ACM SIGPLAN Workshop on Curry and Functional Logic Programming (WCFLP 2005), pp. 8–13. ACM Press, New York (2005)Caballero, R.: Algorithmic Debugging of Java Programs. In: Proc. of the 2006 Workshop on Functional Logic Programming (WFLP 2006). Electronic Notes in Theoretical Computer Science, pp. 63–76 (2006)Caballero, R., Martí-Oliet, N., Riesco, A., Verdejo, A.: A Declarative Debugger for Maude Functional Modules. Electronic Notes in Theoretical Computer Science 238, 63–81 (2009)Davie, T., Chitil, O.: Hat-delta: One Right Does Make a Wrong. In: Seventh Symposium on Trends in Functional Programming, TFP 2006 (April 2006)Fritzson, P., Shahmehri, N., Kamkar, M., Gyimóthy, T.: Generalized Algorithmic Debugging and Testing. LOPLAS 1(4), 303–322 (1992)Hirunkitti, V., Hogger, C.J.: A Generalised Query Minimisation for Program Debugging. In: Adsul, B. (ed.) AADEBUG 1993. LNCS, vol. 749, pp. 153–170. Springer, Heidelberg (1993)Insa, D., Silva, J.: An Algorithmic Debugger for Java. In: Proc. of the 26th IEEE International Conference on Software Maintenance, pp. 1–6 (2010)Insa, D., Silva, J.: Optimal Divide and Query (extended version). Available in the Computing Research Repository (July 2011), http://arxiv.org/abs/1107.0350Lloyd, J.W.: Declarative Error Diagnosis. New Gen. Comput. 5(2), 133–154 (1987)Luo, Y., Chitil, O.: Algorithmic debugging and trusted functions. Technical report 10-07, University of Kent, Computing Laboratory, UK (August 2007)Lux, W.: Münster Curry User’s Guide (release 0.9.10 of May 10, 2006), http://danae.uni-muenster.de/~lux/curry/user.pdfMacLarty, I.: Practical Declarative Debugging of Mercury Programs. PhD thesis, Department of Computer Science and Software Engineering, The University of Melbourne (2005)Naish, L., Dart, P.W., Zobel, J.: The NU-Prolog Debugging Environment. In: Porto, A. (ed.) Proceedings of the Sixth International Conference on Logic Programming, Lisboa, Portugal, pp. 521–536 (June 1989)Nilsson, H.: Declarative Debugging for Lazy Functional Languages. PhD thesis, Linköping, Sweden (May 1998)Pope, B.: A Declarative Debugger for Haskell. PhD thesis, The University of Melbourne, Australia (2006)Shapiro, E.: Algorithmic Program Debugging. MIT Press (1982)Silva, J.: A Comparative Study of Algorithmic Debugging Strategies. In: Puebla, G. (ed.) LOPSTR 2006. LNCS, vol. 4407, pp. 143–159. Springer, Heidelberg (2007)Silva, J.: An Empirical Evaluation of Algorithmic Debugging Strategies. Technical Report DSIC-II/10/09, UPV (2009), http://www.dsic.upv.es/~jsilva/research.htm#tech

A Generalized Model for Algorithmic Debugging

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-27436-2_16Algorithmic debugging is a semi-automatic debugging technique that is present in practically all mature programming languages. In this paper we claim that the state of the practice in algorithmic debugging is a step forward compared to the state of the theory. In particular, we argue that novel techniques for algorithmic debugging cannot be supported by the standard internal data structures used in this technique, and a generalization of the standard definitions and algorithms is needed. We identify two specific problems of the standard formulation and implementations of algorithmic debugging, and we propose a reformulation to solve both problems. The reformulation has been done in a paradigm-independent manner to make it useful and reusable in different programming languages.This work has been partially supported by the EU (FEDER) and the Spanish Ministerio de Economía y Competitividad (Secretaría de Estado de Investigación, Desarrollo e Innovación) under Grant TIN2013-44742-C4-1-R and by the Generalitat Valenciana under Grant PROMETEOII/2015/013. David Insa was partially supported by the Spanish Ministerio de Educación under FPU Grant AP2010-4415.Insa Cabrera, D.; Silva Galiana, JF. (2015). A Generalized Model for Algorithmic Debugging. En Logic-Based Program Synthesis and Transformation. Springer. 261-276. https://doi.org/10.1007/978-3-319-27436-2_16261276Eclipse (2003). http://www.eclipse.org/Barbour, T., Naish, L.: Declarative debugging of a logical-functional language. Technical report, University of Melbourne (1994)Braßel, B., Siegel, H.: Debugging lazy functional programs by asking the oracle. In: Chitil, O., Horváth, Z., Zsók, V. (eds.) IFL 2007. LNCS, vol. 5083, pp. 183–200. Springer, Heidelberg (2008)Caballero, R.: A declarative debugger of incorrect answers for constraint functional-logic programs. In: Proceedings of the 2005 ACM-SIGPLAN Workshop on Curry and Functional Logic Programming (WCFLP 2005), pp. 8–13. ACM Press, New York, USA (2005)Caballero, R., Martin-Martin, E., Riesco, A., Tamarit, S.: EDD: A declarative debugger for sequential erlang programs. In: Ábrahám, E., Havelund, K. (eds.) TACAS 2014 (ETAPS). LNCS, vol. 8413, pp. 581–586. Springer, Heidelberg (2014)Caballero, R., Riesco, A., Verdejo, A., Martí-Oliet, N.: Simplifying questions in maude declarative debugger by transforming proof trees. In: Vidal, G. (ed.) LOPSTR 2011. LNCS, vol. 7225, pp. 73–89. Springer, Heidelberg (2012)Cheda, D., Silva, J.: State of the practice in algorithmic debugging. Electron. Notes Theor. Comput. Sci. 246, 55–70 (2009)Davie, T., Chitil, O.: Hat-delta: one right does make a wrong. In: Butterfield, A., (ed.) Proceedings of the 17th International Workshop on Implementation and Application of Functional Languages (IFL 2005), p. 11, September 2005Davie, T., Chitil, O.: Hat-delta: One right does make a wrong. In: Proceedings of the 7th Symposium on Trends in Functional Programming (TFP 2006), April 2006Fritzson, P., Shahmehri, N., Kamkar, M., Gyimóthy, T.: Generalized algorithmic debugging and testing. ACM Lett. Program. Lang. Syst. (LOPLAS) 1(4), 303–322 (1992)González, J., Insa, D., Silva, J.: A new hybrid debugging architecture for eclipse. In: Gupta, G., Peña, R. (eds.) LOPSTR 2013, LNCS 8901. LNCS, vol. 8901, pp. 183–201. Springer, Heidelberg (2014)Hermanns, C., Kuchen, H.: Hybrid debugging of java programs. In: Escalona, M.J., Cordeiro, J., Shishkov, B. (eds.) ICSOFT 2011. CCIS, vol. 303, pp. 91–107. Springer, Heidelberg (2013)Insa, D., Silva, J.: An algorithmic debugger for java. In: Proceedings of the 26th IEEE International Conference on Software Maintenance (ICSM 2010), pp. 1–6 (2010)Insa, D., Silva, J.: Automatic transformation of iterative loops into recursive methods. Inf. Soft. Technol. 58, 95–109 (2015)Insa, D., Silva, J., Riesco, A.: Speeding up algorithmic debugging using balanced execution trees. In: Veanes, M., Viganò, L. (eds.) TAP 2013. LNCS, vol. 7942, pp. 133–151. Springer, Heidelberg (2013)Insa, D., Silva, J., Tomás, C.: Enhancing declarative debugging with loop expansion and tree compression. In: Albert, E. (ed.) LOPSTR 2012. LNCS, vol. 7844, pp. 71–88. Springer, Heidelberg (2013)Lloyd, J.: Declarative error diagnosis. New Gener. Comput. 5(2), 133–154 (1987)Lux, M.: Münster Curry User’s Guide, May 2006. http://danae.uni-muenster.de/lux/curry/user.pdf ,MacLarty, I.D.: Practical Declarative Debugging of Mercury Programs. Ph.D. thesis, University of Melbourne (2005)Naish, L., Dart, P.W., Zobel, J.: The NU-Prolog debugging environment. In: Porto, A. (ed.) Proceedings of the 6th International Conference on Logic Programming (ICLP 1989), pp. 521–536. Lisboa, Portugal (1989)Nilsson, H.: Declarative Debugging for Lazy Functional Languages. Ph.D. thesis, Linköping, Sweden, May 1998Nilsson, H.: How to look busy while being as lazy as ever: the implementation of a lazy functional debugger. J. Funct. Program. 11(6), 629–671 (2001)Nilsson, H., Fritzson, P.: Algorithmic debugging for lazy functional languages. J. Funct. Program. 4(3), 337–370 (1994)Nilsson, H., Sparud, J.: The evaluation dependence tree: an execution record for lazy functional debugging. Technical report, Department of Computer and Information Science, Linköping (1996)Nilsson, H., Sparud, J.: The evaluation dependence tree as a basis for lazy functional debugging. Autom. Softw. Eng. 4(2), 121–150 (1997)Pope, B.: A Declarative Debugger for Haskell. Ph.D. thesis, The University of Melbourne, Australia (2006)Shapiro, E.: Algorithmic Program Debugging. MIT Press, Cambridge (1982)Shapiro, E.Y.: Inductive inference of theories from facts. Technical report RR 192, Yale University (New Haven, CT US) (1981)Silva, J.: A survey on algorithmic debugging strategies. Adv. Eng. Softw. 42(11), 976–991 (2011)Silva, J.: A vocabulary of program slicing-based techniques. ACM Comput. Surv. 44(3), 1–12 (2012)Thompson, B., Naish, L.: A guide to the nu-prolog debugging environment. Technical report, University of Melbourne (1997

Precise explanation of success typing errors

Nowadays, many dynamic languages come with (some sort of) type inference in order to detect type errors statically. Often, in order not to unnecessarily reject programs which are allowed under a dynamic type discipline, their type inference algorithms are based on non-standard (i.e., not unification based) type inference algorithms. Instead, they employ aggressive forwards and backwards propagation of subtype constraints. Although such analyses are effective in locating actual programming errors, the errors they report are often extremely difficult for programmers to follow and convince themselves of their validity. We have observed this phenomenon in the context of Erlang: for a number of years now its implementation comes with a static analysis tool called Dialyzer which, among other software discrepancies, detects definite type errors (i.e., code points that will result in a runtime error if executed) by inferring success typings. In this work, we extend the analysis that infers success typings, with infrastructure that maintains additional information that can be used to provide precise (i.e., minimal) explanations about the cause of a discrepancy reported by Dialyzer using program slicing. We have implemented the techniques we describe in a publicly available development branch of DialyzerSagonas, K.; Silva Galiana, JF.; Tamarit Muñoz, S. (2013). Precise explanation of success typing errors. En Proceeding PEPM '13 Proceedings of the ACM SIGPLAN 2013 workshop on Partial evaluation and program manipulation. Association for Computing Machinery (ACM). 33-42. doi:10.1145/2426890.2426897S334

Corrección Semi-Automática de Programas Java

[ES] La evaluación es una parte fundamental de la enseñanza. Permite tanto a los estudiantes como a los profesores medir el grado de éxito obtenido en el proceso de aprendizaje. De hecho, la evaluación no debería usarse solo para puntuar, sino que debe ser parte integral de la educación, y proporcionar a los alumnos retroalimentación inmediata. Obviamente, la evaluación debe ser objetiva y justa, y tratar a todos los alumnos por igual. Esto ocurre, p.e., en exámenes de respuesta múltiple, pero, desafortunadamente, no está asegurado en la evaluación de código programado por alumnos, puesto que su corrección es todavía un proceso manual y propenso a errores e interpretaciones. En este artículo proponemos un sistema semi-automático de evaluación de código que utiliza técnicas de caja negra (basadas en output-comparison) y técnicas de caja blanca (que observan las propiedades internas del código). El método propuesto incluye nuevas ideas y técnicas que le permiten evaluar incluso código que no compila.Proyecto financiado por EU (FEDER) y el Ministerio de Econom´ıa y Competitividad (TIN2013- 44742-C4-1-R), por la Generalitat Valenciana (PROMETEO-II/2015/013), y por la Universitat Polit`ecnica de Val`encia (PIME B16). Los autores agradecen el respaldo de la acci´on COST IC1405.Insa Cabrera, D.; Silva Galiana, JF. (2016). Corrección Semi-Automática de Programas Java. En In-Red 2016. II Congreso nacional de innovación educativa y docencia en red. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2016.2016.4326OC

TeMex: The Web Template Extractor

"© ACM} 2015. This is the author's version of the work. It is posted here for your personal use. Not for redistribution. The definitive Version of Record was published in ACM, In Proceedings of the 24th International Conference on World Wide Web (pp. 155-158), http://dx.doi.org/10.1145/2740908.2742835This paper presents and describes TeMex, a site-level web template extractor. TeMex is fully automatic, and it can work with online webpages without any preprocessing stage (no information about the template or the associated webpages is needed) and, more importantly, it does not need a prede- fined set of webpages to perform the analysis. TeMex only needs a URL. Contrarily to previous approaches, it includes a mechanism to identify webpage candidates that share the same template. This mechanism increases both recall and precision, and it also reduces the amount of webpages loaded and processed. We describe the tool and its internal architecture, and we present the results of its empirical evaluation.This work has been partially supported by the EU (FEDER) and the Spanish Ministerio de Economía y Competitividad (Secretaría de Estado de Investigación, Desarrollo e Innovación) under Grant TIN2013-44742-C4-1-R and by the Generalitat Valenciana under Grant PROMETEOII/2015/013. David Insa was partially supported by the Spanish Ministerio de Educación under FPU Grant AP2010-4415. Salvador Tamarit was partially supported by research project POLCA, Programming Large Scale Heterogeneous Infrastructures (610686), funded by the European Union, STREP FP7.Alarte, J.; Insa Cabrera, D.; Silva Galiana, JF.; Tamarit Muñoz, S. (2015). TeMex: The Web Template Extractor. ACM. https://doi.org/10.1145/2740908.2742835SOverlay extension. Available from URL: https://developer.mozilla.org/en-US/Add-ons/Overlay_Extensions, 2005.J. Alarte, D. Insa, J. Silva, and S. Tamarit. Automatic Detection of Webpages that Share the Same Web Template. In M. H. ter Beek and A. Ravara, editors, Proceedings of the 10th International Workshop on Automated Specification and Verification of Web Systems (WWV 14), volume 163 of Electronic Proceedings in Theoretical Computer Science, pages 2--15. Open Publishing Association, July 2014.J. Alarte, D. Insa, J. Silva, and S. Tamarit. A Benchmark Suite for Template Detection and Content Extraction. CoRR, abs/1409.6182, 2014.Z. Bar-Yossef and S. Rajagopalan. Template detection via data mining and its applications. In Proceedings of the 11th International Conference on World Wide Web (WWW'02), pages 580--591, New York, NY, USA, 2002. ACM.M. Baroni, F. Chantree, A. Kilgarriff, and S. Sharoff. Cleaneval: a Competition for Cleaning Web Pages. In Proceedings of the International Conference on Language Resources and Evaluation (LREC'08), pages 638--643. European Language Resources Association, may 2008.D. Gibson, K. Punera, and A. Tomkins. The volume and evolution of web page templates. In A. Ellis and T. Hagino, editors, Proceedings of the 14th International Conference on World Wide Web (WWW'05), pages 830--839. ACM, may 2005.T. Gottron. Evaluating content extraction on HTML documents. In V. Grout, D. Oram, and R. Picking, editors, Proceedings of the 2nd International Conference on Internet Technologies and Applications (ITA'07), pages 123--132. National Assembly for Wales, sep 2007.D. d. C. Reis, P. B. Golgher, A. S. Silva, and A. H. F. Laender. Automatic web news extraction using tree edit distance. In Proceedings of the 13th International Conference on World Wide Web (WWW'04), pages 502--511, New York, NY, USA, 2004. ACM.K. Vieira, A. L. da Costa Carvalho, K. Berlt, E. S. de Moura, A. S. da Silva, and J. Freire. On finding templates on web collections. World Wide Web, 12(2):171--211, 2009.K. Vieira, A. S. da Silva, N. Pinto, E. S. de Moura, J. a. M. B. Cavalcanti, and J. Freire. A fast and robust method for web page template detection and removal. In Proceedings of the 15th ACM International Conference on Information and Knowledge Management (CIKM'06), pages 258--267, New York, NY, USA, 2006. ACM.T. Weninger, W. Henry Hsu, and J. Han. CETR: Content Extraction via Tag Ratios. In M. Rappa, P. Jones, J. Freire, and S. Chakrabarti, editors, Proceedings of the 19th International Conference on World Wide Web (WWW'10), pages 971--980. ACM, apr 2010.L. Yi, B. Liu, and X. Li. Eliminating noisy information in web pages for data mining. In Proceedings of the 9th ACM SIGKDD International Conference on Knowledge Discovery and Data mining (KDD'03), pages 296--305, New York, NY, USA, 2003. ACM

Enhancing Trace Debugging with Algorithmic and Omniscient Debugging

During many years, Print Debugging has been the most used method for debugging. Nowadays, however, industrial languages come with a trace debugger that allows programmers to trace computations step by step using breakpoints and state viewers. Almost all modern programming environments include a trace debugger that allows us to inspect the state of a computation in any given point. Nevertheless, this debugging method has been criticized for being completely manual and time-consuming. Other debugging techniques have appeared to solve some of the problems of Trace Debugging, but they suffer from other problems such as scalability. In this work we present a new hybrid debugging technique. It is based on a combination of Trace Debugging, Algorithmic Debugging and Omniscient Debugging to produce a synergy that exploits the best properties and strong points of each technique. We describe the architecture of our hybrid debugger and our implementation that has been integrated into Eclipse as a plugin.This work has been partially supported by the Spanish Ministerio de Economía y Competitividad (Secretaría de Estado de Investigación, Desarrollo e Innovación) under grant TIN2008-06622-C03-02 and by the Generalitat Valenciana under grant PROMETEO/2011/052. David Insa was partially supported by the Spanish Ministerio de Educación under FPU grant AP2010-4415.González, J.; Insa Cabrera, D.; Silva Galiana, JF. (2013). Enhancing Trace Debugging with Algorithmic and Omniscient Debugging. En Logic-Based Program Synthesis and Transformation. Springer. 183-201. http://hdl.handle.net/10251/72827S18320

¿Aprendo más trabajando solo o en pareja? ¿Aprendo más estando cerca o lejos de la pizarra?

[ES] Este artculo desarrolla un estudio estadstico a partir de un experimentorealizado en dos escuelas universitarias de la Universitat Politecnica deValencia. El objetivo principal del estudio es cuanticar como la distanciade los alumnos al profesor y la pizarra en el aula afecta a su rendimientoacademico. Un segundo objetivo pretende determinar si trabajar en parejao de manera individual tambien afecta al rendimiento. En el experimentohemos recogido y procesado informacion sobre la posicion exacta de cadaalumno en el aula y en el laboratorio durante dos cursos academicos.Tambien se registro cada cambio de posicion, as como sus notas en diferentesexamenes, cursos y asignaturas tanto de teora como de practicas.Nuestro experimento ha producido gran cantidad de datos que han sidoanalizados usando metodos estadsticos avanzados como ANOVA, el testHSD post-hoc de Tukey, y el test de Mantel basado en el coeciente decorrelacion producto-momento de Pearson.Proyecto financiado por EU (FEDER) y el Ministerio de Econom´ıa y Competitividad (TIN2013- 44742-C4-1-R), por la Generalitat Valenciana (PROMETEO-II/2015/013), y por la Universitat Polit`ecnica de Val`encia (PIME B16). Los autores agradecen el respaldo de la acci´on COST IC1405.Insa Cabrera, D.; Silva Galiana, JF.; Tamarit Muñoz, S. (2016). ¿Aprendo más trabajando solo o en pareja? ¿Aprendo más estando cerca o lejos de la pizarra?. En In-Red 2016. II Congreso nacional de innovación educativa y docencia en red. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2016.2016.4300OC

Graph generation to statically represent CSP processes

The CSP language allows the specification and verification of complex concurrent systems. Many analyses for CSP exist that have been successfully applied in different industrial projects. However, the cost of the analyses performed is usually very high, and sometimes prohibitive, due to the complexity imposed by the non-deterministic execution order of processes and to the restrictions imposed on this order by synchronizations. In this work, we define a data structure that allows us to statically simplify a specification before the analyses. This simplification can drastically reduce the time needed by many CSP analyses. We also introduce an algorithm able to automatically generate this data structure from a CSP specification. The algorithm has been proved correct and its implementation for the CSP's animator ProB is publicly available. © 2011 Springer-Verlag.This work has been partially supported by the Spanish Ministerio de Ciencia e Innovación under grant TIN2008-06622-C03-02, by the Generalitat Valenciana under grant ACOMP/2010/042, and by the Universidad Politécnica de Valencia (Program PAID-06-08). Salvador Tamarit was partially supported by the Spanish MICINN under FPI grant BES-2009-015019.Llorens Agost, ML.; Oliver Villarroya, J.; Silva Galiana, JF.; Tamarit Muñoz, S. (2011). Graph generation to statically represent CSP processes. En Logic-Based Program Synthesis and Transformation. Springer Verlag (Germany). 6564:52-66. https://doi.org/10.1007/978-3-642-20551-4_4S52666564Brassel, B., Hanus, M., Huch, F., Vidal, G.: A Semantics for Tracing Declarative Multi-paradigm Programs. In: Moggi, E., Warren, D.S. (eds.) 6th ACM SIGPLAN Int’l Conf. on Principles and Practice of Declarative Programming (PPDP 2004), pp. 179–190. ACM, New York (2004)Butler, M., Leuschel, M.: Combining CSP and B for specification and property verification. In: Fitzgerald, J., Hayes, I.J., Tarlecki, A. (eds.) FM 2005. LNCS, vol. 3582, pp. 221–236. Springer, Heidelberg (2005)Hoare, C.A.R.: Communicating Sequential Processes. Prentice-Hall, Upper Saddle River (1985)Kavi, K.M., Sheldon, F.T., Shirazi, B., Hurson, A.R.: Reliability Analysis of CSP Specifications using Petri Nets and Markov Processes. In: 28th Annual Hawaii Int’l Conf. on System Sciences (HICSS 1995). Software Technology, vol. 2, pp. 516–524. IEEE Computer Society, Washington, DC, USA (1995)Ladkin, P., Simons, B.: Static Deadlock Analysis for CSP-Type Communications. In: Responsive Computer Systems (Ch. 5). Kluwer Academic Publishers, Dordrecht (1995)Leuschel, M., Butler, M.: ProB: an Automated Analysis Toolset for the B Method. Journal of Software Tools for Technology Transfer 10(2), 185–203 (2008)Leuschel, M., Llorens, M., Oliver, J., Silva, J., Tamarit, S.: Static Slicing of CSP Specifications. In: Hanus, M. (ed.) 18th Int’l Symp. on Logic-Based Program Synthesis and Transformation (LOPSTR 2008), pp. 141–150. Technical report, DSIC-II/09/08, Universidad Politécnica de Valencia (July 2008)Leuschel, M., Llorens, M., Oliver, J., Silva, J., Tamarit, S.: SOC: a Slicer for CSP Specifications. In: Puebla, G., Vidal, G. (eds.) 2009 ACM SIGPLAN Symposium on Partial Evaluation and Semantics-based Program Manipulation (PEPM 2009), pp. 165–168. ACM, New York (2009)Leuschel, M., Llorens, M., Oliver, J., Silva, J., Tamarit, S.: The MEB and CEB static analysis for CSP specifications. In: Hanus, M. (ed.) LOPSTR 2008. LNCS, vol. 5438, pp. 103–118. Springer, Heidelberg (2009)Llorens, M., Oliver, J., Silva, J., Tamarit, S.: A Semantics to Generate the Context-sensitive Synchronized Control-Flow Graph (extended). Technical report DSIC, Universidad Politécnica de Valencia, Valencia, Spain (June 2010), http://www.dsic.upv.es/~jsilvaLlorens, M., Oliver, J., Silva, J., Tamarit, S.: Transforming Communicating Sequential Processes to Petri Nets. In: Topping, B.H.V., Adam, J.M., Pallarés, F.J., Bru, R., Romero, M.L. (eds.) Seventh Int’l Conference on Engineering Computational Technology (ICECT 2010). Civil-Comp Press, Stirlingshire, UK, Paper 26 (2010)Roscoe, A.W., Gardiner, P.H.B., Goldsmith, M., Hulance, J.R., Jackson, D.M., Scattergood, J.B.: Hierarchical Compression for Model-Checking CSP or How to Check 1020 Dining Philosophers for Deadlock. In: Brinksma, E., Cleaveland, R., Larsen, K.G., Margaria, T., Steffen, B. (eds.) TACAS 1995. LNCS, vol. 1019, pp. 133–152. Springer, Heidelberg (1995)Roscoe, A.W.: The Theory and Practice of Concurrency. Prentice Hall, Upper Saddle River (2005

Content Extraction based on Hierarchical Relations in DOM Structures

This article introduces a new approach for content extraction that exploits the hierarchical inter-relations of the elements in a webpage. Content extraction is a technique used to extract from a webpage the main textual content. This is useful in order to filter out the advertisements and all the additional information that is not part of the main content. The main idea behind our approach is to use the DOM tree as an explicit representation of the inter-relations of the elements in a webpage. Using the information contained in the DOM tree we can identify blocks of content and we can easily determine what of the blocks contains more text. Thanks to this information, the technique achieves a considerable recall and precision. Using the DOM structure for content extraction gives us the benefits of other approaches based on the syntax of the webpage (such as characters, words and tags), but it also gives us a very precise information regarding the related components in a block, thus, producing very cohesive blocks.López Romero, S.; Silva Galiana, JF.; Insa Cabrera, D. (2012). Content Extraction based on Hierarchical Relations in DOM Structures. Research and Development in Computer Science and Engineering. 45:5-12. http://hdl.handle.net/10251/47738S5124