The interest of authors to publish their contributions in ComSIS Journal is constantly increasing in recent years. At the same time, there is an evident interest of conference and workshop organizers to relate their events with recognized international journals. On the one hand side, we believe that it is a common trend in a global research community. On the other side, it was an inspiration for ComSIS editors how to attract contributions of a recognized quality and also create proper publishing capacities in ComSIS. Facing to the issue, this year we decided to keep our policy of publishing additional special issue, apart from two regular ones. The first of them, titled Advances in Computer Languages, Modeling and Agents, is in front of you.

Editors of this special issue were inspired by several events they organized during 2011 year in the following, somehow closely related domains: Advances in Programming Languages; Computer Languages, Implementations and Tools; Software Technologies for Intelligent Collaborative Systems; and Applications of Software Agents. These events included: (i) Workshop on Advances in Programming Languages (WAPL) organized within the scope of the Federated Conference on Computer Science and Information Systems (FedCSIS) in Szczecin, Poland; (ii) Symposium on Computer Languages, Implementations and Tools (SCLIT) organized within the scope of the International Conference of Numerical Analysis and Applied Mathematics (ICNAAM) in Kassandra – Halkidiki, Greece; (iii) Special Session on Software Technologies for Intelligent Collaborative Systems (STIX) organized within the scope of the International Conference on System Theory, Control and Computing (ICSTCC) in Sinaia, Romania; and (iv) Workshop on Applications of Software Agents (WASA) organized at the University of Novi Sad in Serbia. After an open call to the prospective authors to submit their papers, we received 54 submissions. After rigorous reviewing procedure, the same as for regularly submitted papers, we finally accepted 14 papers presenting both theoretical and practical contributions in field of Advances in Computer Languages, Modeling and Agents.

Daniel Rodríguez-Cerezo, Antonio Sarasa-Cabezuelo, and José-Luis Sierra in the paper "A Systematic Approach to the Implementation of Attribute Grammars with Conventional Compiler Construction Tools" present structure-preserving coding patterns to code arbitrary non-circular attribute grammars as syntax-directed translation schemes for bottom-up and top-down parser generation tools. In order to bridge the gap between attribute grammar-based specifications and final implementations, they propose articulating the language processor development process as the explicit transformation of the initial attribute grammar-based specification to the final implementation.

One of often emergent issues in the area of domain specific languages (DSL) is how to come to a successful implementation of a DSL in some problem domain. In the paper "Implementation of EasyTime Formal Semantics using a LISA Compiler Generator" by Iztok Fister Jr., Marjan Mernik, Iztok Fister, and Dejan Hrnčič, a DSL EasyTime is presented. It enables the controlling of an agent by writing the events within a database. The EasyTime language is implemented by a LISA tool that enables the automatic construction of compilers from language specifications, using Attribute Grammars. Let us notice that EasyTime was successfully applied for measuring time at the World Championship for the double ultra triathlon in 2009.

The next paper "Using Aspect-Oriented State Machines for Detecting and Resolving Feature Interactions", by Tom Dinkelaker, Mohammed Erradi, and Meryeme Ayache also targets the area of DSL development and implementation. The authors present an approach to manage feature interactions. They used a formal model based on the finite state machines and Aspect-Oriented technology to specify, detect and resolve features interactions. They also developed a DSL to handle finite state machines using a pattern matching technique.

Milan Čeliković, Ivan Luković, Slavica Aleksić, and Vladimir Ivančević in the paper "A MOF based Meta-Model and a Concrete DSL Syntax of IIS*Case PIM Concepts" use a meta modeling approach based on MOF to specify a meta model and a DSL for creating platform independent models of information systems. They implemented their meta model in the IIS*Case – a software tool that provides a model driven approach to information system design and generating application prototypes.

Boštjan Slivnik in "LL Conflict Resolution using the Embedded Left LR Parser" starts from the fact that choosing the right parsing method is an important issue in a design of a modern compiler. He presented a method for resolving LL(k) conflicts using small LR(k) parsers and also proposed the use of an embedded left LR(k) parser within an LL(k) parser, instead of a deterministic finite automation. As it produces the left parse it does not require rescanning of tokens already scanned or backtracking, and thus guarantees the linear parsing time for all LR(k) grammars.

Jan Trávníček, Jan Janoušek, and Borivoj Melichar in the paper "Indexing Ordered Trees for (Nonlinear) Tree Pattern Matching by Pushdown Automata" address finding occurrences of tree patterns in trees as one of the important problems with many applications. The authors presented a new kind of acyclic pushdown automata, the tree pattern pushdown automaton and the nonlinear tree pattern pushdown automaton, constructed for an ordered tree. These automata accept all tree patterns and nonlinear tree patterns, respectively, which match the tree and represent a full index of the tree for such patterns. They analyzed timings of their implementation and showed that for a given tree the running time is linear to the size of the input pattern.

Črt Gerlec, Gordana Rakić, Zoran Budimac and Marjan Heričko in the paper “A Programming Language Independent Framework For Metrics-Based Software Evolution And Analysis” provide a framework for evaluating software metrics and analyzing software structure during software development. The main contribution of the framework is a programming language independency based on universal representation of the source code by the enriched Concrete Syntax Tree (eCST). This universality leads to consistency in change analysis and quality control during the software evolution. This characteristic gets additional value today when software projects are complex and heterogonous consisting of numerous components developed in broad spectra of languages.

Paper High-level Multi-core Programming with C++11 by Zalan Szugyi, Mark Torok, Norbert Pataki and Tamas Kozsik proposes extensions of the C++ Standard Template Library based on the features of C++11. These extensions provide enhancement of the standard library to be more powerful in the field of the multi-core programming. Approach of the authors is based on functors and lambda expressions. The contribution of the paper is illustrated by three case studies.

Developing an agent that can operate in heterogeneous network of multi-agent systems requires regeneration of the agent’s executable code, as well as modifications in the way it communicates with the environment. The main goal of the paper “Supporting Heterogeneous Agent Mobility with ALAS” is providing an effective solution to the heterogeneous agent mobility problem. Following this goal a novel agent-oriented programming language, named ALAS, is proposed. Authors (Dejan Mitrović, Mirjana Ivanović, Zoran Budimac and Milan Vidaković) provide the design of the ALAS platform and an experiment to illustrate that an agent written in ALAS is able to work in truly heterogeneous networks of multi-agent systems.

In the paper “Language Engineering for Syntactic Knowledge Transfer,” Mihaela Colhon presents an English-Romanian parallel treebank construction method. The method relies on a bilingual, word-aligned corpus with morphosyntactic annotations, in order to construct a syntactic annotated parallel corpus. An important fact is that the presented algorithm is defined at the abstract level of syntactic components, and is therefore language independent.

Gleb Peregud, Julian Zubek, Maria Ganzha and Marcin Paprzycki, in “Implementing an eXAT-based distributed monitoring system prototype,” introduce a prototype system for monitoring resource consumption in distributed networks, such as LAN, Grid, and Cloud. A special care is dedicated to maintaining fault-tolerance of dynamic networks, in which nodes may “disappear” at any given moment. The prototype is developed in Erlang, which proved to be a good implementation platform.

In the article “Modeling a Holonic Agent based Solution by Petri Nets,” Carlos Pascal and Doru Panescu use Petri nets to highlight certain problems in holonic manufacturing execution systems. Namely, the inadequate resource allocation and its negative consequence on agent planning are first shown by Petri net models, and then experimentally proven. The authors consider a solution based on a staff holon, in charge of conflict detection and resolution.

Next, a prototype system for resource management is proposed by Maria Ganzha, Adam Omelczuk, Marcin Paprzycki and Mateusz Wypysiak, in the paper “Information resource management in an agent-based virtual organization – initial implementation.” Their system operates in virtual organizations, matching entities in need of information resources with entities that can provide those resources in an adequate manner. The virtual organizations themselves are modeled in terms of different roles played by intelligent agents, with the roles being hierarchical ordered.

Finally, in “Decentralized Management of Building Indoors through Embedded Software Agents,” Giancarlo Fortino and Antonio Guerrieri deal with decentralized, agent-based management of smart buildings. The proposed architecture relies on wireless sensors and actuator networks for monitoring and control, and can be easily configured with any existing building. Their system has been tested in computer laboratories used by students, and was able to detect significant energy waste of idle workstations.

On behalf of the ComSIS Consortium and Editorial Board, let us express our great thanks to the reviewers and all the authors for their high-quality work and extraordinary enthusiasm. We are convinced that all of their work significantly contributes in meeting the high quality standards aiming ComSIS to a recognized international journal.

Editors of the special issue
Mirjana Ivanović, Ivan Luković, Zoran Budimac