Cloud application portability: an initial view.

Growing interest towards cloud application platforms has resulted in a large number of platform offerings to be already available on the market and new related products to be continuously launched. However, there are a number of challenges that prevent cloud application platforms from becoming widely adopted. One such challenge is application portability. This paper reports on an ongoing effort to explore the area of cloud application portability. We briefly examine the issue of heterogeneity in cloud platforms and highlight specific platform characteristics that may hinder the portability of cloud applications. We present some high level approaches and existing work that attempts to address this challenge. In order to narrow down the area of our exploration we have been carrying out an experiment in cross-platform application development and deployment with four prominent cloud platforms: OpenShift, Google App Engine, Heroku, and Amazon Elastic Beanstalk. We briefly discuss our initial conclusions from this ongoing experimentation

Proširiv i prilagodljiv okvir za statičku analizu nezavisnu od ulaznog jezika

In modern approach to software development, a great importance is given to monitoring  of software quality in early development phases. Therefore, static analysis becomes more important. Furthermore, software projects are becoming more complex and heterogeneous. These characteristics are reflected in a diversity of functionalities and  variety of computer languages and the technologies used for their development. Because of that consistency in static analysis becomes more important than it was earlier. In this dissertation SSQSA: Set of Software Quality Static Analyzers is described. The aim  of the SSQSA framework  is consistent static analysis. This goal is reached by introducing new intermediate source code representation called eCST: enriched Concrete Syntax Tree. The dissertation mostly focuses on eCST, intermediate representations derived from it, and their generation with description of the  tools involved in it. The main characteristic of eCST is language independence which gives to SSQSA framework two-level extensibility: supporting a new language and supporting a new  analysis. This leads to eciency of adding both level supports and consistency of added functionalities. To prove the concept, support for more than 10 characteristic languages was introduced. Furthermore, characteristic static analysis techniques (software metrics calculation,  code-clone detection, etc.) were implemented and integrated in the framework.  Established SSQSA framework provides the infrastructure for the further development of the complete platform for software quality control.U modernim pristupima razvoju softvera veliki značaj pridaje se kontroli kvaliteta softvera u ranim fazama razvoja. Zbog toga, statička analiza postaje sve značajnija. Takođe, softverski proizvodi postaju sve kompleksniji i heterogeni. Ove karakteristike se ogledaju u raznovrsnosti jezika i tehnologija koje se koriste u procesu razvoja softvera. Zbog toga, konzistentnost u statičkoj analizi dobija veći značaj nego što je to bio slučaj ranije. U ovoj disertaciji opisan je SSQSA skup statičkih analizatora za kontrolu kvaliteta (eng. Set of Software Quality Static Analyzers). Namena SSQSA okvira je konzistentna statička analiza. Cilj se postiže uvođenjem nove međureprezentacije  izvornog koda nazvane eCST (obogaćeno konkretno sintaksno stablo, eng. enriched  Concrete Syntax Tree). Fokus disertacije je primarno na eCST reprezenataciji koda,  reprezentacijama izvedenjim iz eCST i procesu njihovog generisanja, sa opisom oruđa angažovanim u ovim procesima. Osnovna i najbitnija karakteristika eCST reprezenatacije je nezavisnost od jezika u kom je izvorni kod pisan, što SSQSA okviru daje proširivost na dva nivoa: kroz podršku za nove jezike i kroz podršku za nove analize. Ovo dovodi do efikasnog uvođenja funkcionalnosti na oba navedena nivoa, kao i do konzistentnosti uvedenih funkcionalnosti.  Kao dokaz ispravnosti koncepta, podrška za više od 10 ulaznih jezika je uvedena. Takođe, implementirane su karakteristične tehnike statičke analize (izračunavanje softverskih metrika, otkrivanje duplikata u kodu, itd.) i integrisane u SSQSA okvir.  Na opisani način, postavljanjem SSQSA okvira, obezbeđena je infrastruktura za dalji razvoj kompletne platforme za kontrolu kvaliteta softvera.

Proširiv i prilagodljiv okvir za statičku analizu nezavisnu od ulaznog jezika

In modern approach to software development, a great importance is given to monitoring  of software quality in early development phases. Therefore, static analysis becomes more important. Furthermore, software projects are becoming more complex and heterogeneous. These characteristics are reflected in a diversity of functionalities and  variety of computer languages and the technologies used for their development. Because of that consistency in static analysis becomes more important than it was earlier. In this dissertation SSQSA: Set of Software Quality Static Analyzers is described. The aim  of the SSQSA framework  is consistent static analysis. This goal is reached by introducing new intermediate source code representation called eCST: enriched Concrete Syntax Tree. The dissertation mostly focuses on eCST, intermediate representations derived from it, and their generation with description of the  tools involved in it. The main characteristic of eCST is language independence which gives to SSQSA framework two-level extensibility: supporting a new language and supporting a new  analysis. This leads to eciency of adding both level supports and consistency of added functionalities. To prove the concept, support for more than 10 characteristic languages was introduced. Furthermore, characteristic static analysis techniques (software metrics calculation,  code-clone detection, etc.) were implemented and integrated in the framework.  Established SSQSA framework provides the infrastructure for the further development of the complete platform for software quality control.U modernim pristupima razvoju softvera veliki značaj pridaje se kontroli kvaliteta softvera u ranim fazama razvoja. Zbog toga, statička analiza postaje sve značajnija. Takođe, softverski proizvodi postaju sve kompleksniji i heterogeni. Ove karakteristike se ogledaju u raznovrsnosti jezika i tehnologija koje se koriste u procesu razvoja softvera. Zbog toga, konzistentnost u statičkoj analizi dobija veći značaj nego što je to bio slučaj ranije. U ovoj disertaciji opisan je SSQSA skup statičkih analizatora za kontrolu kvaliteta (eng. Set of Software Quality Static Analyzers). Namena SSQSA okvira je konzistentna statička analiza. Cilj se postiže uvođenjem nove međureprezentacije  izvornog koda nazvane eCST (obogaćeno konkretno sintaksno stablo, eng. enriched  Concrete Syntax Tree). Fokus disertacije je primarno na eCST reprezenataciji koda,  reprezentacijama izvedenjim iz eCST i procesu njihovog generisanja, sa opisom oruđa angažovanim u ovim procesima. Osnovna i najbitnija karakteristika eCST reprezenatacije je nezavisnost od jezika u kom je izvorni kod pisan, što SSQSA okviru daje proširivost na dva nivoa: kroz podršku za nove jezike i kroz podršku za nove analize. Ovo dovodi do efikasnog uvođenja funkcionalnosti na oba navedena nivoa, kao i do konzistentnosti uvedenih funkcionalnosti.  Kao dokaz ispravnosti koncepta, podrška za više od 10 ulaznih jezika je uvedena. Takođe, implementirane su karakteristične tehnike statičke analize (izračunavanje softverskih metrika, otkrivanje duplikata u kodu, itd.) i integrisane u SSQSA okvir.  Na opisani način, postavljanjem SSQSA okvira, obezbeđena je infrastruktura za dalji razvoj kompletne platforme za kontrolu kvaliteta softvera.

Methods of Database Schema Transformations in Support of the Information System Reengineering Process

Cilj istraživanja realizovanih u ovom radu, bio je je da se formalno opišu mogući pristupi transformacijama različitih opisa baza podataka iz jednog modela podataka u drugi i praktično provere kroz njihovu implementaciju u okviru jednog CASE alata, namenjenog projektovanju informacionih sistema i baza podataka. U skladu sa postavljenim ciljem definisan je metodološki pristup i softversko okruženje IIS*Ree koje omogućava visok nivo automatizacije procesa reinženjeringa informacionih sistema. Okruženje IIS*Ree, zasnovano na MDSD principima, kao krajnji rezultat generiše šemu baze podataka u izabranom ciljnom, konceptualnom ili implementacionom modelu podataka, kao i prototip aplikacije.The goal of the research presented in this paper is to formally specify approaches to transformation of database specifications between different data models. The transformations are then to be implemented and tested using a CASE tool for modelling information systems and databases. Following this goal, a methodological approach is defined together with a software named IIS*Ree that provides a high level of automation of the information system reengineering process. The IIS*Ree software, developed in accordance to MDSD principles, generates database schemas specified in a target, conceptual or implementation data model, as well as application prototypes

Methods of Database Schema Transformations in Support of the Information System Reengineering Process

Cilj istraživanja realizovanih u ovom radu, bio je je da se formalno opišu mogući pristupi transformacijama različitih opisa baza podataka iz jednog modela podataka u drugi i praktično provere kroz njihovu implementaciju u okviru jednog CASE alata, namenjenog projektovanju informacionih sistema i baza podataka. U skladu sa postavljenim ciljem definisan je metodološki pristup i softversko okruženje IIS*Ree koje omogućava visok nivo automatizacije procesa reinženjeringa informacionih sistema. Okruženje IIS*Ree, zasnovano na MDSD principima, kao krajnji rezultat generiše šemu baze podataka u izabranom ciljnom, konceptualnom ili implementacionom modelu podataka, kao i prototip aplikacije.The goal of the research presented in this paper is to formally specify approaches to transformation of database specifications between different data models. The transformations are then to be implemented and tested using a CASE tool for modelling information systems and databases. Following this goal, a methodological approach is defined together with a software named IIS*Ree that provides a high level of automation of the information system reengineering process. The IIS*Ree software, developed in accordance to MDSD principles, generates database schemas specified in a target, conceptual or implementation data model, as well as application prototypes

Fast Mode Assignment for Quality Scalable Extension of the High Efficiency Video Coding (HEVC) Standard: A Bayesian Approach

ABSTRACT The new compression standard, known as the High Efficiency Video Coding (HEVC), aims at significantly improving the compression efficiency compared to previous standards. There has been significant interest in developing a scalable version of this standard. As expected, the HEVC scalable video version, which is called SHVC, increases the complexity of the codec compared to the non-scalable counterpart. In this paper, we propose an adaptive fast mode assigning method based on a Bayesian classifier that reduces SHVC's coding complexity by up to 68.55%, while maintaining the overall quality and bit-rates

Exascale machines require new programming paradigms and runtimes

Extreme scale parallel computing systems will have tens of thousands of optionally accelerator-equiped nodes with hundreds of cores each, as well as deep memory hierarchies and complex interconnect topologies. Such Exascale systems will provide hardware parallelism at multiple levels and will be energy constrained. Their extreme scale and the rapidly deteriorating reliablity of their hardware components means that Exascale systems will exhibit low mean-time-between-failure values. Furthermore, existing programming models already require heroic programming and optimisation efforts to achieve high efficiency on current supercomputers. Invariably, these efforts are platform-specific and non-portable. In this paper we will explore the shortcomings of existing programming models and runtime systems for large scale computing systems. We then propose and discuss important features of programming paradigms and runtime system to deal with large scale computing systems with a special focus on data-intensive applications and resilience. Finally, we also discuss code sustainability issues and propose several software metrics that are of paramount importance for code development for large scale computing systems

Factors affecting the use of smart mobile examination platforms by universities’ postgraduate students during the COVID 19 pandemic : an empirical study

Recent years have seen an increasingly widespread use of online learning technologies. This has prompted universities to make huge investments in technology to augment their position in the face of extensive competition and to enhance their students’ learning experience and efficiency. Numerous studies have been carried out regarding the use of online and mobile phone learning platforms. However, there are very few studies focusing on how university students will accept and adopt smartphones as a new platform for taking examinations. Many reasons, but most recently and importantly the COVID-19 pandemic, have prompted educational institutions to move toward using both online and mobile learning techniques. This study is a pioneer in examining the intention to use mobile exam platforms and the prerequisites of such intention. The purpose of this study is to expand the Technology Acceptance Model (TAM) by including four additional constructs: namely, content quality, service quality, information quality, and system quality. A self-survey method was prepared and carried out to obtain the necessary basic data. In total, 566 students from universities in the United Arab Emirates took part in this survey. Smart PLS was used to test the study constructs and the structural model. Results showed that all study hypotheses are supported and confirmed the effect of the TAM extension factors within the UAE higher education setting. These outcomes suggest that the policymakers and education developers should consider mobile exam platforms as a new assessment platform and a possible technological solution, especially when considering the distance learning concept. It is good to bear in mind that this study is initial and designed to explore using smartphones as a new platform for student examinations. Furthermore, mixed-method research is needed to check the effectiveness and the suitability of using the examination platforms, especially for postgraduate higher educational levels