Detecting anomaly and failure in Web applications

Improving Web application quality will require automated evaluation tools. Many such tools are already available either as commercial products or research prototypes. The authors use their automated evaluation tools, ReWeb and TestWeb, for Web analysis and testing that improves Web pages and applications and to find some anomalies and failures in four case studies.     

'98 Escherichia coli SWISS-2DPAGE database update

The combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), computer image analysis and several protein identification techniques allowed the Escherichia coli SWISS-2DPAGE database to be established. This is part of the ExPASy molecular biology server accessible through the WWW at the URL address http://www.expasy.ch/ch2d/ch2d-top.html . Here we report recent progress in the development of the E. coli SWISS-2DPAGE database. Proteins were separated with immobilized pH gradients in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. To increase the resolution of the separation and thus the number of identified proteins, a variety of wide and narrow range immobilized pH gradients were used in the first dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride membranes and spots were visualized by amido black staining. Protein identification techniques such as amino acid composition analysis, gel comparison and microsequencing were used, as well as a recently described Edman "sequence tag" approach. Some of the above identification techniques were coupled with database searching tools. Currently 231 polypeptides are identified on the E. coli SWISS-2DPAGE map: 64 have been identified by N-terminal microsequencing, 39 by amino acid composition, and 82 by sequence tag. Of 153 proteins putatively identified by gel comparison, 65 have been confirmed. Many proteins have been identified using more than one technique. Faster progress in the E. coli proteome project will now be possible with advances in biochemical methodology and with the completion of the entire E. coli genome.     

Design-code traceability recovery: selecting the basic linkage properties

Traceability ensures that software artifacts of subsequent phases of the development cycle are consistent. Few works have so far addressed the problem of automatically recovering traceability links between object-oriented (OO) design and code entities. Such a recovery process is required whenever there is no explicit support of traceability from the development process. The recovered information can drive the evolution of the available design so that it corresponds to the code, thus providing a still useful and updated high-level view of the system.

Automatic recovery of traceability links can be achieved by determining the similarity of paired elements from design and code. The choice of the properties involved in the similarity computation is crucial for the success of the recovery process. In fact, design and code objects are complex artifacts with several properties attached. The basic anchors of the recovered traceability links should be chosen as those properties (or property combinations) which are expected to be maintained during the transformation of design into code. This may depend on specific practices and/or the development environment, which should therefore be properly accounted for.

In this paper different categories of basic properties of design and code entities will be analyzed with respect to the contribution they give to traceability recovery. Several industrial software components will be employed as a benchmark on which the performances of the alternatives are measured.     

Designing and Conducting an Empirical Study on Test Management Automation

Test management aims at organizing, documenting and executing test cases, and at generating execution reports. The adoption of a support tool and of a standard process for such activities is expected to improve the current practice. ITALO is a European project devoted to the evaluation of the benefits coming from test management automation. In this paper the experiences collected and the lessons learned during ITALO are summarized. A formal methodology was adopted for the selection of a support tool among those available from the market. A survey of the current practice in component testing was conducted to adapt the existing process model so as to obtain the greatest benefits from automation. An empirical study was then designed to measure the effects that are expected to be produced by the new test process complemented with the introduction of the support tool. Three pilot projects were conducted to measure the benefits obtained from tool usage and process modification. Results are presented and discussed in this paper.     

Empirical studies in reverse engineering: state of the art and future trends

Starting with the aim of modernizing legacy systems, often written in old programming languages, reverse engineering has extended its applicability to virtually every kind of software system. Moreover, the methods originally designed to recover a diagrammatic, high-level view of the target system have been extended to address several other problems faced by programmers when they need to understand and modify existing software. The authors’ position is that the next stage of development for this discipline will necessarily be based on empirical evaluation of methods. In fact, this evaluation is required to gain knowledge about the actual effects of applying a given approach, as well as to convince the end users of the positive cost–benefit trade offs. The contribution of this paper to the state of the art is a roadmap for the future research in the field, which includes: clarifying the scope of investigation, defining a reference taxonomy, and adopting a common framework for the execution of the experiments.     

Effects of Lysine and Methionine Fortification on Dough and Bread Characteristics

Wheat flour from the Hermosillo Hard Red Spring cultivar in Sonora, Mexico was fortified with various levels of lysine and methionine. The effects of added amino acids on the rheological properties were measured by the Brabender Farinograph and the Chopin Alveograph. Nutritional characteristics were measured by Protein Efficiency Ratio (PER). Dough development and stability times were not significantly different between control and fortified flours. Water absorption and Alveograph results indicated differences between samples. PERs were significantly improved by fortification. Overall bread acceptability was not significantly different from unfortified samples.     

EEG data compression techniques

Electroencephalograph (EEG) and Holter EEG data compression techniques which allow perfect reconstruction of the recorded waveform from the compressed one are presented and discussed. Data compression permits one to achieve significant reduction in the space required to store signals and in transmission time. The Huffman coding technique in conjunction with derivative computation reaches high compression ratios (on average 49% on Holter and 58% on EEG signals) with low computational complexity. By exploiting this result a simple and fast encoder/decoder scheme capable of real-time performance on a PC was implemented. This simple technique is compared with other predictive transformations, vector quantization, discrete cosine transform (DCT), and repetition count compression methods. Finally, it is shown that the adoption of a collapsed Huffman tree for the encoding/decoding operations allows one to choose the maximum codeword length without significantly affecting the compression ratio. Therefore, low cost commercial microcontrollers and storage devices can be effectively used to store long Holter EEG's in a compressed format     

Applying and combining three different aspect Mining Techniques

Understanding a software system at source-code level requires understanding the different concerns that it addresses, which in turn requires a way to identify these concerns in the source code. Whereas some concerns are explicitly represented by program entities (like classes, methods and variables) and thus are easy to identify, crosscutting concerns are not captured by a single program entity but are scattered over many program entities and are tangled with the other concerns. Because of their crosscutting nature, such crosscutting concerns are difficult to identify, and reduce the understandability of the system as a whole. In this paper, we report on a combined experiment in which we try to identify crosscutting concerns in the JHotDraw framework automatically. We first apply three independently developed aspect mining techniques to JHotDraw and evaluate and compare their results. Based on this analysis, we present three interesting combinations of these three techniques, and show how these combinations provide a more complete coverage of the detected concerns as compared to the original techniques individually. Our results are a first step towards improving the understandability of a system that contains crosscutting concerns, and can be used as a basis for refactoring the identified crosscutting concerns into aspects. M. Ceccato is a PhD student in ITC-irst in Trento, Italy. He received his degree in Software Engineering from the University of Padova, Italy, in 2003. The master thesis concerned the Re-engineering of an existing big-sized data warehouse application. The project was developed in the Information Technology department in Alcoa Servizi. His research interests are on source code analysis and manipulation, especially for the the migration of object-oriented code to aspect-oriented programming. He collaborates with King’s College London and Loyola College in Maryland on the automatic support for this migration process. He has been involved in the organization and in the program committee of a number of AOP-related events, such as Late Workshop, in Chicago (2005) and in Bonn, Germany (2006), held within the major Aspect Oriented Programming conference (AOSD) and 3rd European Workshop on Aspects in Software (EWAS’06) in Enschede, The Netherlands. Marius Marin is a Ph.D. researcher in the Software Evolution Reseach Laboratory at Delft University of Technology, the Netherlands. He was granted an engineering degree by the Technical University of Civil Engineering, Bucharest, in 2000, and Licentiate in Economic Computer Science from the Academy of Economic Studies, Bucharest, in 2002. Before starting his Ph.D. studies, he worked as a software engineer in industry. His main research interests are in the area of reverse engineering, software modularization and modeling, and aspect-oriented software development. He is the main author of the publicly available aspect mining tool FINT and he publishes at international conferences in the aforementioned topics. He has been involved in program- and organizing committees of several workshops related to aspect mining. Kim Mens obtained his Ph.D. in Computer Science at the Vrije Universiteit Brussel, on “architectural conformance checking,” for which he used a declarative meta-programming approach. After his Ph.D. he became a full-time professor (chargé de cours) at the Université catholique de Louvain-la-Neuve (UCL). In addition to his current interest in logic meta-programming and intensional views, Kim Mens is one of the originators of the reuse contracts technique for automatically detecting conflicts in evolving software. He has been formally involved in several research networks related to software evolution. He has a strong interest in object-oriented and aspect-oriented software development and has actively participated in the organization of several workshops and conferences on those topics. He combines all these different research interests under the common denominator of co-evolution (between source code and earlier life-cycle software artifacts). Other research topics that fit this common theme and in which he is interested are software architecture, software maintenance, reverse engineering, software transformation, software restructuring and renovation, aspect mining and evolution of aspect programs. L. Moonen is an assistant professor in the Software Evolution Research Lab at Delft University of Technology and a researcher at the Centre for Mathematics and Computer Science (CWI), the Netherlands. His research interests are the design and development of advanced program analysis tools and techniques that support development, maintenance and evolution of large software systems. Concrete topics include the reverse engineering and exploration of views on software systems and their use for understanding and assessing software quality attributes such as evolvability, reliability and security. Dr. Moonen received an MSc (cum laude, Computer Science, 1996) and PhD (Computer Science, 2002) from the University of Amsterdam. He is one of the founders of the Software Improvement Group, a company that specializes in tools and consultancy to help organizations solve their legacy problems. He publishes regularly at, and serves on organizing-, steering- and program committees of, international workshops and conferences on reverse engineering (WCRE), source code analysis (SCAM), software maintenance (ICSM), program understanding (ICPC), reengineering (CSMR), aspect mining (Dagstuhl 06302, TEAM) and software security (CoBaSSA). Paolo Tonella is a senior researcher at ITC-irst, Trento, Italy. He received his laurea degree cum laude in Electronic Engineering from the University of Padova, Italy, in 1992, and his Ph.D. degree in Software Engineering from the same University, in 1999, with the thesis “Code Analysis in Support to Software Maintenance.” Since 1994 he has been a full time researcher of the Software Engineering group at ITC-irst. He participated in several industrial and European Community projects on software analysis and testing. He is the author of “Reverse Engineering of Object Oriented Code,” Springer, 2005. His current research interests include reverse engineering, aspect oriented programming, empirical studies, Web applications and testing. Tom Tourwé obtained the degree of Licentiate in Computer Science in 1997 and Ph.D. in Science in 2002 at the Vrije Universiteit Brussel. He is currently associated to the Centrum voor Wiskunde en Informatica, based in Amsterdam, The Netherlands, where he works as a post- doctoral researcher in the Ideals project. His main research interests lie in the broad area of software engineering, and include aspect-oriented software evolution and re-engineering in particular. He published several peer-reviewed articles on these topics in international journals and conferences, and organised a number of workshops on those themes.     

Continuous fermentation of sugar cane syrup using immobilized yeast cells

Several strains of Saccharomyces sp. and commercial Baker's yeast were immobilized by adhesion onto chrysotile, a fibrous magnesium silicate (Mg6Si4O10 (OH)8). The activity of the cells is higher when immobilized, mainly for fermentation of 30 to 50% w/v glucose solutions. In the medium containing 30% w/v glucose, the initial fermentation rate increased 1.2-2.5 times. Yields were in the range of 80.4 to 97.3% for the immobilized cells and 72.7 to 84.5% for the free cells. A packed bed reactor for continuous fermentation was set up using one of the tested strains immobilized onto chrysotile. An average productivity of 20 to 25 g.l(-1).h(-1) was obtained in the first 20 d, and an average of 16 g.l(-1).h(-1) was obtained after 50 d of operation.