The second issue of Volume 14 of the Computer Science and Information Systems journal, now in front of you, contains 10 regular articles and a special section “Advanced Information Engineering Systems” with three extended versions of selected papers from the 28th International Conference on Advanced Information Systems Engineering (CAiSE 2016) held in Ljubljana, Slovenia, June 13-17. We thank the guest editors Sergio España from Utrecht University (Netherlands) and David G. Rosado from University of Castilla-La Mancha (Ciudad Real, Spain), authors and reviewers for their dedication and great efforts invested into the current issue of our journal.

It is our pleasure to announce the new impact factors of ComSIS, the highest so far. The two-year impact factor of our journal for 2016 is 0.837, while the five-year impact factor is 0.881.

The regular article section opens with “Performance Evaluation and Implementation of IP and Robust Header Compression Schemes for TCP and UDP Traffic in Static and Dynamic Wireless Contexts,” by Máté Tömösközi et al. This work evaluates different header compression methods for IP-based cellular networks, namely IP Header Compression (IPHC) for UDP and TCP, comparing it with two Robust Header Compression (RoHC) methods in real-world mobile scenarios. The results show that although, IPHC could perform better on a unidirectional channel, in all other scenarios RoHC was generally superior, especially on TCP connections prone to packet reordering.

Dragan Matić et al., in “Variable Neighborhood Search for Solving Bandwidth Coloring Problem,” present a variable neighborhood search algorithm for solving the bandwidth coloring problem (BCP) and the bandwidth multicoloring problem (BMCP), both generalizations of the well-known vertex coloring problem. The presented method is demonstrated to be comparable with the state-of-the-art, improving 2 out of 33 previous best-known BMCP solutions.

“Integer Arithmetic Approximation of the HoG Algorithm” by Srđan Sladojević et al. studies how introducing integer (fixed-point ) arithmetic into a popular object detection system based on the Histogram of Oriented Gradients (HoG) representation deviates the results compared to the reference implementation. Deviations are explored on four levels where integer arithmetic is introduced: HoG descriptor magnitude calculation, HoG descriptor angle calculation, normalization, and SVM classification. It is determined that 13-bit integer variables are sufficient to accurately implement the considered system in integer arithmetic. More general conclusions are also drawn about the usefulness of integer arithmetic in a wider class of applications.

In “R -Tree for Phase Change Memory,” Elkhan Jabarov et al. explore the use of the R-Tree spatial data structure on phase change memory (PCM), proposing several ways of configuring the R-Tree in order to address the endurance problem. Experimental results show that the number of write operations decreased 56 times on average when using the proposed R-Tree, with the proposed modified R-Tree improving processing time by 23% on average, compared to a regular R-Tree.

Kyosung Jeong et al., in “A Flash-Aware Buffering Scheme with the On-the-Fly Redo for Efficient Management of Databases in Flash Storage,” propose a new buffering scheme for flash storage which reduces the number of updates by evicting invalidated pages without writing them to storage. For this purpose, a new on-the-fly redo mechanism is designed, that enables restoring the lost updates of a page in normal database processing. Experimental results demonstrate that the proposed scheme provides better performance by significantly reducing the amount of page updates.

In their article entitled “Effort Estimation in Global Software Development - A Systematic Review,” Dilani Wickramaarachchi and Richard Lai present the conclusions of a comprehensive literature overview related to effort estimation in global software development (GSD), summarizing the hidden costs in GSD, and discussing the open research issues of effort estimation.

The article “Preserving Use Case Flows in Source Code: Approach, Context, and Challenges” by Michal Bystrický and Valentino Vranić presents InFlow, an approach for preserving use case flows in source code. The preservation of individual steps from use case flows takes the form of counterpart statements, and their ordering, and is achieved by mimicking each use case flow by a sequence of method implementations, with the aid of annotations.

Petri Rantanen, in article “REST API Example Generation Using Javadoc,” presents a Javadoc extension that can be used to produce example data in combination with automatically generated API method call examples, whose main goal is to is to make generating method call examples for (RESTful) web services easier. The benefits of the approach are discussed through the implementation of a media content analysis service.

In “LTR – MDTS Structure – A Structure for Multiple Dependent Time Series Prediction,” Predrag Pecev and Miloš Racković present a neural network structure and appropriate training algorithm suited for multiple dependent time-series prediction, motivated by, and applied to the problem of predicting synchronized basketball referees’ movement during a basketball action. The approach builds on the multilayer perceptron architecture and the backpropagation algorithm, tackling the issues produced by the backward time lapse effect.

The final regular article, “An Online-Processing Critical Patient Monitoring System – An Interoperability Overview,” by Filipe Portela et al. describes the implementation of PaLMS – Patient Localization and Management System, and its integration into a hospital interoperability platform employing intelligent agents. Patent localization is of vital importance in enabling real-time processes like data mining, since it provides information whether a patient is present in bed.

Special section “Advanced Information Engineering Systems” consists of 3 articles accepted for publishing among four papers selected from CAiSE Forum 2016 and three papers selected from the 6th International Workshop on Information Systems Security Engineering (WISSE 2016). The CAiSE Forum is a meeting place for disseminating and debating new ideas and tools related to the area of advanced information systems engineering. WISSE is a workshop focused on methods, models, practices and tools for secure information systems engineering from both the academic and the industrial perspectives.

“Visual Requirements Modeling for Cross-Device Systems” by Dennis Wolters et al. presents an extended form of use case diagrams able to model cross-devise systems, i.e. systems that are used and accessed through multiple devices in parallel or sequentially by switching from one device to another. Using this approach it is possible to specify which device types can be used when performing a certain use case and what kinds of cross-device interactions are supported.

In “Modeling the Delivery of Security Advisories and CVEs,” Jukka Ruohonen et al. consider three structural factors thought to affect the turnaround times between the publication of security advisories and Common Vulnerabilities and Exposures (CVEs): software product age at the time of advisory release, severity of coordinated vulnerabilities, and amounts of CVEs referenced in advisories. Empirical results show that the three factors have only limited value in predicting turnaround times. However, the paper offers a discussion of new research directions for better understanding problems in vulnerability coordination.

Orestis Mavropoulos et al., in “A Conceptual Model to Support Security Analysis in the Internet of Things,” propose a conceptual model to support decision makers during security analysis of Internet of Things (IoT) systems. The model is based on an architecture-oriented approach that incorporates sociotechnical concepts into the security analysis of an IoT system, and its use is demonstrated on a small-scale smart home example.

Mirjana Ivanović

Managing Editor
Miloš Radovanović

Guest Editors of Special Section “Advanced Information Engineering Systems”

Sergio España
Utrecht University, Netherlands

David G. Rosado
University of Castilla-La Mancha, Ciudad Real, Spain