Journal of Information and Organizational Sciences

293-304

Authors: Paweł Baranowski, Adrian Stepniak

Deep convolutional neural networks (CNNs) became an industry standard in image processing. However, in order to keep their high efficiency, a large annotated sample is required in the case of supervised learning. In this paper we apply the techniques specific for relatively small sample to a court files dataset. Specifically, we propose transfer learning and semisupervised learning to classify scanned page as having a table or not. We use four CNNs architectures established in the literature and find that transfer learning improves the classification performance, compared to the fully supervised learning. This result is especially evident in the scenarios where only a part of convolutioanl layers are transferred. The gains from semisupervised learning are ambiguous, as the results vary over CNNs architectures. Overall, our results show that office documents classification can achieve high accuracy when transferring initial convolutional layers is applied.

323-344

Authors: Aakansha Singh, Harminder Kaur Gujral

The present research aims to study the relation between emotional intelligence and organizational culture during the Covid-19 pandemic. Emotional intelligence is an individual's ability to understand and manage their own and others' emotions. This ability can be instrumental in driving the culture of universities and colleges. During this crucial time of Covid-19, there is a sudden shift from traditional/ face-to-face teaching to online/hybrid education; it is vital to provide a congenial environment and culture to teachers and students to promote a smooth and amiable teaching/learning experience. The data was collected from a sample of 10 colleges of higher education from NCR. The respondents included academicians of different academic ranks. 232 questionnaires were received, out of which 213 respondent's data was usable. Convenience sampling was used in this research to collect data from the colleges. According to the findings, there is a strong relation between emotional intelligence and organizational culture. The organizational culture and its dimensions are strongly affected by emotional intelligence. The most robust relationship exists between managing emotions and managing change in the organization.

361-375

Authors: Blaženka Divjak, Darko Grabar, Barbi Svetec, Petra Vondra

We present a comprehensive learning design (LD) concept and tool, motivated by the needs identified by higher education (HE) practitioners. The concept and tool aim at implementing contemporary research findings and theory to support balanced LD planning (BDP). The student-centered BDP concept and tool provide innovation to LD planning by strongly focusing on learning outcomes (LOs) and student workload, aligning study program and course level LOs, ensuring constructive alignment and assessment validity, enhancing LD by using learning analytics, and enabling flexible use in different contexts and pedagogical approaches. The ongoing work has been done according to design science methodology, with positive first feedback from HE practitioners. We identify areas for further research and improvement, including testing the BDP tool in real-world HE contexts and its integration with learning management systems. This could help close the gap between intended (often innovative) LDs and their implementation in real teching and learning environments.

391-420

Authors: Eda Sultan Arar, Serap Şahin

The aim of the research is to examine the work ethics perceptions of academics from different generations and the relationship between these perceptions and workplace deviation behaviors. In line with the purpose, the questionnaire prepared by using 5 questions with demographic variables, academic ethical values scale and workplace deviation behavior scale were applied to 472 academicians working at state universities in Ankara and the nearby provinces. The results revealed moderately negative relationship between academic ethical values and one of its sub-dimensions which is the values for the institution and workplace deviation behaviors. Moreover, weak and strong negative relationships were found between academic ethical values and other sub-factors of workplace deviation behaviors. Intergenerational differences were found between academic ethical values and academic ethical values towards the teaching process and serious workplace deviation towards the organization, and between academic ethical values towards colleagues and deviant behaviors towards the organization.

433-451

Authors: Manish Mohan, Anil Jadhav

No industry can thrive without customers and with customers comes the chances of customer churn. Since customer churn have direct-impact on the revenue, all the industries are focusing in understanding the factors influencing churn and are developing methods to predict the customer churn effectively. Today, never as before, customers have wide variety of options to choose between any service or product. In addition, nowadays customers enjoy multiple subscriptions of service providers across sectors. In this study we aim to identify: i) Factors influencing customer churn on OTT platform, and ii) Predict customer churn on OTT platform. The data for this study is collected from 317 respondents, using questionnaire method, who have multiple OTT platform subscription. The questionnaire data contains 19 items which includes demographic features, usage of OTG platform, and user contentment factors about OTT service. We have identified factors influencing customer churn in Over-The-Top (OTT) platform by combining Recursive Feature Elimination (RFE), Linear Regression, and Ridge Regression feature ranking methods. We have used Hierarchical Logistic Regression, to understand impact of two newly introduced factors namely 'Multiple Subscription' and 'Switching Frequency' on the overall performance of the customer churn prediction. Finally, customer churn prediction is done using Decision Tree, Random Forest, AdaBoost, and Gradient boosting techniques. We found that random forest method gives better prediction results.

473-489

Authors: Farouk Ouatik, Mohammed Erritali, Fahd Ouatik, Mostafa Jourhmane

The process of traditional school guidance is carried out by specialists. They make a study of the student files based on the marks of the first year and the second year of the baccalaureate. Considering the progressive number of students and also the lack of time to make the decision, as the selection of the specialty has a great effect on the academic course of the students, we have realized a system of specialty recommendation, to computerize the orientation process and save time. But the major problem is that the students do not care about this process and pay no attention to it despite its importance. As well as the software which makes the orientation is chargeable. To order these specialties to take the best specialty. We have arrived at a problem of multi-criteria which makes it impossible to make a decision with these criteria. Because these criteria do not have the same importance and also are not compatible, as there are criteria that must be maximum and other criteria must be minimal. To solve this problem, two systems of orientation and academic reorientation of students have been implemented. In both systems, the SMOTE method has been used to balance the learning data in the preprocessing phase. Then in the treatment phase, we sorted the specialties using in the first system, a hybridization of TOPSIS method and the information gain to find the weights of the criteria used, and in the second system, we used a hybridization of the AHP method and information gain. The results obtained indicate that before balancing data using the SMOTE method, the total accuracy of TOPSIS (84.20%) is higher than the total accuracy of AHP (83.71%). After applying balancing data using the SMOTE method, the total accuracy has increased. The total accuracy of TOPSIS (91.35%) is also higher than the total accuracy of AHP (90.83%). For the complexity of the two methods, it is related to the number of criteria and the number of alternatives. If the number of criteria is more than 10 criteria, the complexity of TOPSIS is less than the complexity of AHP, and vice versa. The complexity of the two methods also depends on the number of alternatives, if the number of alternatives exceeds 10, the TOPSIS method becomes more complex than the AHP method. In general, the system based on TOPSIS method and the information gain is more precise than the system based on the AHP method and the information gain. But the complexity of the AHP method is less than the complexity of the TOPSIS method.

15-40

Authors: Ali Asghar Sadabadi; Saeed Ramezani; Kiarash Fartash

Scientometrics is one of the most important scales for evaluating scientific outputs. Co-word and social network analysis (SNA) were used to investigate relationships in the field of social accounting researches indexed on Scopus. The findings of the study indicate that the most frequent topics and vocabulary in this area is economic analysis, economic and social effects. Moreover, the most valuable subject areas were identified: based on closeness, they are water resources, tourism economics and structural adjustment. Based on centrality, economic impact, economic analysis, environmental economics and income distribution. The results of the study indicate that many important social and environmental issues can be assessed through social accounting. Co-authorship analysis revealed that the co-authorship network in this domain was discrete and with low density. By utilizing the co-occurrence map, researchers and policymakers can make policy making more effective through being aware of the research trends and hot topics in social accounting.

63-77

Authors: Amir Najafi; Sedigeh Soleimanpur; Zoheir Morady

Information Technology is a key factor in eliminating the limitations posed by time and location and gives a much better and a faster access to informaition. In other words, technology has revolutionized work methods as a result of which, the paper which was used as a substrate for writing the work upon it has now been replaced by an electronic substrate. The changes created by technology include the use of Blockchain, IoT (Internet of Things), Cloud Accounting and Big Data to do accounting in automated form.The statistical sample of this study is given on the basis of the 171 person Cochran formulae consisting of financial managers, accountants and auditors of the Tehran city. Empirical results show that the use of Information Technology has a very significant role on the quality of Accounting Information and all these factors are influential in the quality of accounting system.

103-127

Authors: Andrew Arim; Joseph Wamema

One of the predominant challenges facing banks in low resource countries is the management of Digital Financial Services (DFS) risks. Many banks are making worthwhile efforts to boost the factors that make them come on top of the challenges, unfortunately they have fallen short. This article sought to develop an e-risk management framework for DFS in Ugandan banks. Design Science Research paradigm, a mono-method qualitative research method and a case study research strategy was adopted. Questionnaires, interviews and document review were the main data collection methods. Findings from this study indicate that banks in Uganda use a handful of DFS business models and face a number of DFS risks including; talent for DFS, technology, strategy, governance, product, client acquisition, crime/fraud, regulation, and agent management among others. Notwithstanding, Ugandan banks should carefully balance IT spend across customer expectations, improve cybersecurity and internal process and regularly check its IT security.

141-156

Authors: Mahdi Hoseinpour; Sanjar Salajghe; Mohammad Jalal Kamali

This study aims to investigate the organizational factors affecting knowledge concealment in scientific contexts. This study has taken a mixed approach to identify these factors, so what makes it unique is the pluralism of data collection methods. Also, using the "Delphi" method, a conceptual model of organizational factors affecting knowledge concealment in scientific contexts is presented. The statistical sample included 314 employees of the Islamic Azad University of Khorasan Razavi who were selected through the random sampling method. They filled knowledge concealment questionnaire by Demirkasimoglu (2016) and a scholar-made questionnaire. Data were analyzed using the structural equation method (SEM) in AMOS software. Findings revealed that the coefficient correlation of organizational culture, reward system, organizational structure, organizational support, organizational justice, quality of work-life, and leadership style with knowledge concealment was -0.62, -0.27, -0.49, -1.30, -0.77, -0.39, and -0.88, respectively. The results indicate that organizational factors have an inverse and significant relationship with knowledge concealment.

173-195

Authors: Blaženka Divjak; Petra Vondra; Katarina Pažur Aničić

This paper elaborates the design of a National Learning Analytics (LA) and Educational Data Mining System for pre-tertiary education in Croatia. The described approach consists of the following five phases: 1) objectives setting, 2) user needs analysis, 3) data availability analysis, 4) dashboards pre-design and 5) validation of functionalities. There is an evident research gap, as well as the lack of practical examples about the development of a Learning Analytics System (LAS) for pre-tertiary education on the national and/or regional level. Therefore, this research aims to make a scientific contribution by filling the recognized gap, but also contribute to solving the practical issues of national schools’ LAS development. To increase the usability of an LAS, the involvement of all end users is essential. In the described case, six main user groups were identified: 10-18 years old students, teachers, school management and support staff, regional and national authorities responsible for education, strategic bodies and researchers and, finally, project partners that work on system development. For each of them, separate dashboard functionalities have been designed through several rounds of consultations. Consultations with users started with focus groups and panels, to brainstorm the most important issues they would like to answer in order to enhance learning and teaching. Between the two rounds of consultation, there was an evaluation phase of the relevance of the gathered questions. Finally, targeted users provided feedback on the pre-production functionalities of each dashboard and validated them. In this process, several challenges were detected, including data gathering and protection, ethical issues and interpretation of results for students who are underage, and continuous adjustments to the users’ needs.

213-236

Authors: Bernard Ijesunor Akhigbe; Oladele J. Ososanya; Emmanuel Ajayi Olajubu

This paper presents a formulated mobile-based location-awareness model that was implemented into a Location-awareness System (L-aS hereafter) for finding the pharmacy location where prescribed drugs and their prices are available for sale. The scenario that inspired the model formulation was formalized using the unified modeling language. The model was implemented within the android studio integrated development environment with the L-aS database created through SQL lite database. The system was tested using user experience based testing technique. Based on core system performance testing, the system demonstrated a normal response time, resource utilization (i.e. storage and memory usage), and data use potentials of 414.6ms, 4.964mb and 1.9116 kb/secs, and 3.0296mb respectively. Therefore, the system performed well under ordinary conditions as an android application running on small memory devices. The study concluded that the developed mobile based pharmacy store location-aware system was useful to provide information to purchase prescribed drugs especially in perplexed situation(s).

255-266

Authors: Krishna Priya; Jansi Rani T.

Work life balance is the relationship between, how much time and effort someone spends to work and how much time and effort spend to other elements of their life, such as family, children, friends etc., HR policies are the organization’s continuing guidelines for managing its employees. As in this study, it mainly focuses on what are all roles played by the human resource department on balancing work and life in the Information Technology sector of women professionals. For this research, descriptive research was done with a sample of 200 women professionals from selected IT companies in Chennai using simple random sampling technique. The questionnaire was created using the independent variable of HR policies on work life balance and mediator of continuance commitment with a dependent variable of work life balance. The statistical tools used in this study are CFA, Discriminant validity and Composite reliability with the assistance of SPSS and AMOS software. The research found that, all the item used in the study are reflect a good measure of the variables.

375-397

Authors: Cidália Oliveira; Carmem Leal; António Pinho

This paper aims to confirm the importance of BSC (Balanced Scorecard) in SMEs’ organizational performance. To perform the empirical study of this investigation, a field study, namely a qualitative approach, Multi Case Study was selected and developed in two small and medium organizations (SMEs) in the wine sector. One of the organizations, had the Balanced Scorecard (BSC) implemented while the other did not, which made it possible to ascertain the existing differences among SMEs that apply and those that do not apply BSC. The results showed that BSC has impact on business success. SMEs benefit from the implementation of BSC, consequently SMEs were encouraged to adopt it based on the benefits in terms of performance and measurement of strategic objectives. This study reflects that BSC has been a discussion and research topic over the last few years as it leverages business. Managers seek appropriate BSC tools to implement indicators and monitor these in accordance with the global organizational strategy. Besides BSC provides managers with relevant information to take decisions, define action plans and achieve the whole organizational control.

411-434

Authors: Armen E. Petrosyan

By means of theoretical analysis based on the results of previous research, and the relevant historical and factual material, the author outlines a new theory of formation, transformation, and fission of organizational culture. The mechanism that consolidates organizational culture (selection of “right” persons; adjustment to the common cause; and people’s accommodation with each other), the toolkit for renewing it (involvement of the key bearers of the culture to be introduced; elimination of those inconsistent with it; and translation of the proclaimed values to the “pliant mass” ready to get engaged in changes) as well as the nature of cultural ruptures in organizations and the ways out are brought into relief. The paper promotes a better understanding of the dynamics of organizational culture and gives an access to more efficient instruments to manage it.

451-471

Authors: Maria Jakovljevic; Nkopodi Nkopodi

Educationists are urged to investigate the effect of social networks control. There is a lack of multidisciplinary studies with a focus on coercive social network control in the higher education sector. This exploratory and descriptive study presents a theoretical contemplation of social network control based on ten key elements that influence teaching and learning in higher educational environments. The paper provides a critical analysis of the impact of an economic model on social networks control and examines social engineering through the tenets of digital presence, psychological strategies and tactics. Insights into user-generated content and the learning process of manipulative assimilation that influence current ways of thinking in higher educational contexts are offered through the lens of social networks control mechanisms. A framework for social network control was derived, signifying the flow and dynamics between key elements which might impact on various aspects of social network security and its applications in Higher Education.

495-511

Authors: Kiril Kirilov

Image classification and face recognition has been a popular subject matter for the last several decades. Images are usually handled as transformed as vectors which makes their classification a dimensionality reduction task. Some of the well-known algorithms in the area, such as the Sparsity Preserving Projection (SPP), create new theoretical concepts families, while other successfully modify or combine useful properties of the former ones. Compiled algorithms like Sparse Discriminant Preserving Projections (SDPP) employ the properties of the Sparse Representation (SR) as in their objective functions they include a supervised modification of the sparse weight matrix that considers the intra-class relations. By examining the construction of the SDPP algorithm and by providing some arguments on the supervised SR, in this paper we propose a new subspace learning algorithm, called Inverted Sparse Discriminant Preserving Projection (ISDPP). Likewise SDPP, ISDPP integrates supervised SR with the Fisher’s criterion. In contrast to SDPP, ISDPP incorporates a between-class SR with the Fischer’s within-class scatter matrix. A preliminary round of experiments support the initiative and provide an expectation for possible superior performance of the proposed ISDPP that is confirmed in the next round of empirical examinations.

535-551

Authors: Desabandhu Parasuraman; Sathiyamoorthy Elumalai

Recommender systems have become a vital entity to the business world in form of software tools to make decisions. It estimates the overloaded information and provides the suitable decisions in any kind of business work through online. Especially in the area of e-commerce, recommender systems provide suggestions to users on the items that are likely based upon user’s true interest. Collaborative Filtering and Content Based Filtering are the main techniques of recommender systems. Collaborative Filtering is considered to be the best in all domains and always outperforms Content Based filtering. But, both the techniques have some limitations like data sparsity, cold start, gray sheep and scalability issues. To overcome these limitations, Hybrid Recommender Systems are used by combining Collaborative Filtering and Content Based Filtering. This paper proposes such kind of hybrid system by combining Collaborative Filtering and Content Based Filtering using time variance and machine learning algorithm.

567-578

Authors: Mahsa Fidanboy; Kerim Ozcan; Cemalettin Ocal Fidanboy

The aim of this paper is to develop a scale for measuring organizational adaptation and investigating its relationship with R&D performance. For this purpose, the items were developed in accordance with the dimensions of organization design, and the scale was tested first in a pilot study, and after making revisions and modifications, it was employed in the main study on two different samples, one for exploratory factor analysis (EFA), and the other for confirmatory factor analysis (CFA). The final scale consists of 17 items categorized under 4 dimensions labeled as contextual factors, tasks and roles, labor and labor division, and rules and regulations. The results indicate that except for rules and regulations, all dimensions of organizational adaptation bear higher values in high R&D performance cluster. The organizations who enforce adaptation in all the other three dimensions yield more innovation which will help them in their decisions regarding their adaptive responses.

601-638

Authors: Robertina Zdjelar; Nikolina Žajdela Hrustek

The issue of e-Inclusion has become an important topic and increasingly gains significance if one takes into account the global trend of digital transformation in the development of the information society and that the digital divide is still present. The reason more for taking the e-Inclusion of all social groups as a challenge has recently been the Covid-19 pandemic and natural disasters (earthquakes, floods) that change the norms of social behavior, require adaptation and create new rules. Users’ ability to use digital services and goods as well as open data provided by public and private organizations which ultimately results in greater access to relevant information as well as improved quality of life and are a key factor for the effectiveness of digital transformation and the economic justification of investing in advanced digital technologies, goods and services. The digital divide manifests itself on certain social groups, which is a social problem. However, despite these initiatives, there are still limitations that prevent certain population groups from becoming e-inclusive members of the information society. This paper presents an overview of the analysis results of the research perspective in which scientific and professional papers consider the concepts of e-Inclusion and digital divide as a challenge. The multiperspectiveness and multidimensionality of the concept of e-Inclusion indicates its significant role in the development of the information society.

21-38

Authors: Oleg Tikhonenko; Marcin Ziółkowski

In the paper, we consider non-classical queueing systems with non-homogeneous customers. The non-homogeneity we treat in the following sense: in systems under consideration, we characterize each customer by random capacity (volume) that can have an influence on his service time. We analyze a stochastic process having the sense of the total volume of all customers present in the system at given time instant. Such analysis for different queueing systems with unlimited or limited total volume can be used in designing of nodes of computer and communication networks while determining their buffer space capacity. We discuss basic problems of the theory of these systems and their performance characteristics. We also present some examples and results for systems with random volume customers.

55-75

Authors: Shadrack Katuu

This article provides a brief discussion of ERPs, including how they can be defined, their component parts, and the evolution of technologies since the 1940s. The article then offers a general overview of the current ERP vendor market landscape based on academic journals and industry reports. The article’s methodological approach is a review of both academic literature and industry expert reports, which the author performed to trace trends within the landscape. Results of the analysis demonstrate that the rapidly evolving market landscape dates back at least six decades, and there are many large, longstanding ERP vendors. Yet, opportunities like cloud computing may result in niche products in existing industry players or through start-ups. Nonetheless, technologies such as blockchain are emerging. It remains to be seen how they will impact the ERP market.

95-113

Authors: Heri Akhmadi; Susanawati Susanawati; Nindia Putri Utami; Aris Slamet Widodo

WhatsApp is mobile messaging application which is widely used in communication. However, its use in marketing communication is relatively new. This study investigates WhatsApp user profile, factors that influence the use of WhatsApp and relationship between the factors with WhatsApp usage level in fruit marketing communication. Respondents were selected using census method by taking all fruit wholesalers in Giwangan Fruit Central Market, the largest fruit market in Yogyakarta, Indonesia. Data were analyzed using descriptive methods and Spearman Rank correlation. The results showed that majority of WhatsApp users among traders are male in millennial age, with high school education. Furthermore, the convenience in use and economical reason were the most influential factors in the use of WhatsApp on marketing communication. Moreover, this study found that there was a strong and positive correlation between benefits factors and the use of WhatsApp on fruit marketing communication.

137-169

Authors: Behrije Ramaj-Desku; Fatos Ukaj

The E-marketing strategy is developed as a process of several stages that need to be well analyzed and constantly reviewed. The first stage of this process is situational analysis (internal and external factors). The research was focused on identifying internal and external factors. The Delphi technique was used in combination with the AHP method to answer the research questions. The research was conducted in three stages, according to the Delphi technique. In order to process the data in all three phases of the research Excel, SPSS, and the AHP-ON system were used. 36 experts of tourism industry from Kosovo and Albania took part in this study. Ranked based on the signinficance, of all factors and sub-factors the following indicated the highest influence: entrepreneurial attitudes and knowledge, management support, customer and supplier relationships, IT cost, competitor identification, competitor analysis, and innovation. Based on the scientific literature and the primary results, the conclusion and recommendations were drawn and a model was proposed by the author based on the contingency theory and the TEO framework.

223-241

Authors: Nedim Dedić

Enterprise Architecture (EA) is well researched and well-developed concept, and even a two decades ago there were a plenty of frameworks in this field. However, the functional integration of EA at operational and tactical levels in organisations is identified as one of the biggest challenges faced by many Enterprise Architects today. To overcome this challenge, a comprehensive literature review on EA is conducted, which resulted with the identification of the knowledge gap. To overcome this gap, Enterprise Architecture Fusion Process (EAFP), a novel practical approach that demonstrates the capability of integrating EA activities into operational and tactical activities in respective organisation is developed and presented in this paper.

267-286

Authors: Essam Natsheh

Fuzzy logic controller is one of the most prominent research fields to improve efficiency for process industries, which usually stick to the conventional proportional-integral-derivative (PID) control. The paper proposes an improved version of the three-term PID-like fuzzy logic controller by removing the necessity of having user-defined parameters in place for the algorithm to work. The resulting non-parametric three-term dissimilarity-based clustering fuzzy logic controller algorithm was shown to be very efficient and fast. The performance study was conducted by simulation on armature-controlled and field-controller DC motors, for linguistic type and Takagi-Sugeno-Kang (TSK) models. Comparison of the created algorithm with fuzzy c-means algorithm resulted in improved accuracy, increased speed and enhanced robustness, with an especially high increase for the TSK type model.

309-327

Authors: Margarida Rodrigues; Cidalia Oliveira; Rui Silva

Temporary employment is not influenced by the unemployment rate, but shows a positive relation with the social protection expenses of the companies. Poland is the country with the highest percentage of temporary workers (2013). The objective of this research is to study this flexibility, by obtaining empirical evidence in the European Union, using a quantitative research method. Research is still missing towards a better understanding of the relation between temporary employment and unemployment. The relevance of understanding of the effects of temporary employment in the European Labor Market. As future research, it is suggested that this study be replicated for the time span of 2006 to 2020. This research focuses on the geographical area studied, providing a better understanding of the relation between temporary employment and unemployment. This research is based on quantitative research using a European Union secondary database (Eurostat).

231-246

Authors: Karlo Babić; Francesco Guerra; Sanda Martinčić-Ipšić; Ana Meštrović

Measuring the semantic similarity of texts has a vital role in various tasks from the field of natural language processing. In this paper, we describe a set of experiments we carried out to evaluate and compare the performance of different approaches for measuring the semantic similarity of short texts. We perform a comparison of four models based on word embeddings: two variants of Word2Vec (one based on Word2Vec trained on a specific dataset and the second extending it with embeddings of word senses), FastText, and TF-IDF. Since these models provide word vectors, we experiment with various methods that calculate the semantic similarity of short texts based on word vectors. More precisely, for each of these models, we test five methods for aggregating word embeddings into text embedding. We introduced three methods by making variations of two commonly used similarity measures. One method is an extension of the cosine similarity based on centroids, and the other two methods are variations of the Okapi BM25 function. We evaluate all approaches on the two publicly available datasets: SICK and Lee in terms of the Pearson and Spearman correlation. The results indicate that extended methods perform better from the original in most of the cases.

257-273

Authors: Sofiane Boukelkoul; Ramdane Maamri

This paper presents a DSDEVS-based model “Dynamic Structure Discrete Event System specification” for modeling and simulating business processes with dynamic structure regarding to different contexts. Consequently, this model, formally, improves the reuse of configurable business processes. Thus, the proposed model allows the analysts to personalize their configurable business processes in a sound manner by verifying a set of structure properties, such as, the lack of synchronization and the deadlock by means of simulation. The implementation was done in DEVS-Suite simulator, which is based on DEVSJAVA models.

297-316

Authors: Michal Čerňanský; Ladislav Huraj; Marek Šimon

The paper focuses on design, background and experimental results of real environment of DDoS attacks. The experimental testbed is based on employment of a tool for IT automation to perform DDoS attacks under monitoring. DDoS attacks are still serious threat in both IPv4 and IPv6 networks and creation of simple tool to test the network for DDoS attack and to allow evaluation of vulnerabilities and DDoS countermeasures of the networks is necessary. In proposed testbed, Ansible orchestration tool is employed to perform and coordinate DDoS attacks. Ansible is a powerful tool and simplifies the implementation of the test environment. Moreover, no special hardware is required for the attacks execution, the testbed uses existing infrastructure in an organization. The case study of implementation of this environment shows straightforwardness to create a testbed comparable with a botnet with ten thousand bots. Furthermore, the experimental results demonstrate the potential of the proposed environment and present the impact of the attacks on particular target servers in IPv4 and IPv6 networks.

331-344

Authors: Paweł Kossecki

Common problem in valuation of telecommunication companies is finding comparable data and markets for valuation. The aim of this work was to identify comparable markets for the telecommunication market in Europe. A method for comparison of the markets based on the Multivariate Statistical Analysis was presented. The study covers twenty-two European countries. Using taxonomic measures, these countries were divided into five groups, taking into account the following variables: average monthly service cost of the fixed Internet, average cost of the mobile usage, and average cost of the fixed telephony usage. Within individual groups, the costs of telecommunications services are less diverse than in the entire population; their members can be considered comparable markets. The same method can be used for comparing markets in cases of enterprise valuations in the telecommunication sector, and also in analysis of their level of development.

365-382

Authors: Artur Soboń; Mirosław Kurkowski; Sylwia Stachowiak

Keeping the proper security level of ciphers used in communication networks is today a very important problem. Cryptanalysts ensure a constant need for improvement complexity and ciphers' security by trying to break them. Sometimes they do not instantly try to break the strongest version of the cipher, but they are looking for weaknesses by splitting it and independently checking all algorithm components. Often cryptanalysts also attempt to break cipher by using its weaker version or configuration. There are plenty of mechanisms and approaches to cryptanalysis to solve those challenges. One of them is SAT-based method, that uses logical encoding. In this article, we present our wide analysis and new experimental results of SAT-based, direct cryptanalysis of the RC5 cipher. To perform such actions on the given cipher, we initially create a propositional logical formula, that describes and represents the entire RC5 algorithm. The second step is to randomly generate key and plaintext. Then we determine the ciphertext. In the last step of our computations, we use SAT-solvers. They are particularly designed tools for checking the satisfiability of the Boolean formulas. In our research, we make cryptanalysis of RC5 cipher in the case with plaintext and ciphertext. To get the best result, we compared many SAT-solvers and choose several. Some of them were relatively old, but still very efficient and some were modern and popular.