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This paper describes the results of experiments in predicting students’ performance on a massive open online course (MOOC). Grade reports from MOOC “Data management” on the Russian platform openedu.ru were used for the analysis. It is well known that only a small percent of students who enrolled in MOOCs pass them through. Data mining methods could help to understand the causes of this problem. We tried to predict whether the student will finish an online course or not based on his results during the first weeks. Such prediction if it was performed early enough could help to keep students in the course.

The paper describes the results of a massive open online course (MOOC) “Data management” on the Russian platform of Open Education openedu.ru. Some approaches to the analysis of the results of distance learning, including data mining, are discussed. The produced analysis of the results of studying MOOC helps to understand students and their reasons for leaving the course. This could be taken into account during the renewal of the course. If some of the tasks are too difficult for a certain group of students, these tasks could be changed or an additional training material could be given before those. The offered method gives an opportunity to suggest new interesting topics and tasks that could be added to the course in those weeks when students are dropping out en masse. For some groups of students, additional courses for preliminary training could be recommended. The next task which we’ll try to solve is classification: we’ll try to predict if the course will be completed by the student or not based on their results during the first weeks. The results of such prediction may help to keep students in the course.

This paper describes the impact of using SQL Server temporal tables in transactional and analytic databases. This type of table was added in SQL Server 2016, and it can be extremely useful when we need to store data that describes the different states of some objects at different points in time. For our experiments, we used Open University Learning Analytics Dataset (OULAD) [1], which was imported into the SQL Server database. This dataset contains data about courses, students and their interactions with Virtual Learning Environment for seven selected courses. The temporality was implemented to the only one relational table of the database for more illustrative results. The results of our experiments show significant advantages of temporal databases in comparison with non-temporal relational ones in executing some types of queries as well as in solving data mining problems using SQL Server analysis services.

A diversity of wireless technologies will collaborate to support the fifth-generation (5G) communication networks with their demanding applications and services. Despite decisive progress in many enabling solutions, next-generation cellular deployments may still suffer from a glaring lack of bandwidth due to inefficient utilization of radio spectrum, which calls for immediate action. To this end, several capable frameworks have recently emerged to all help the mobile network operators (MNOs) leverage the abundant frequency bands that are utilized lightly by other incumbents. Along these lines, the recent Licensed Shared Access (LSA) regulatory framework allows for controlled sharing of spectrum between an incumbent and a licensee, such as the MNO, which coexist geographically. This powerful concept has been subject to several early technology demonstrations that confirm its implementation feasibility. However, the full potential of LSA-based spectrum management can only become available if it is empowered to operate dynamically and at high space-time-frequency granularity. Complementing the prior efforts, we in this work outline the functionality that is required by the LSA system to achieve the much needed flexible operation as well as report on the results of our respective live trial that employs a full-fledged commercial-grade cellular network deployment. Our practical results become instrumental to facilitate more dynamic bandwidth sharing and thus promise to advance on the degrees of spectrum utilization in future 5G systems without compromising the service quality of their users.

The article considers the issues related to c evaluation of the effectiveness of interaction of participants of transport and logistics infrastructure in the region. The study was conducted on the example of transport and logistics infrastructure of the Voronezh region. In connection with this method was developed for evaluating the effectiveness of the organization of interaction of participants of transport and logistics infrastructure in the region.

The article presents the imperatives of development of transport and logistics enterprises, conclusions about the organization of the transport and logistics process

The results of the study of the quality indicators of the surface of rolling bearing rings after the operation of fine grinding with an abrasive wheel and polishing with a profile elastic tool of abrasive particles compacted with inertial forces are presented. The advantages of processing with an elastic tool and the effect of processing modes on the roughness of the working surface of the rings, the amount of waviness and cut are shown. Recommendations on the practical application of the new technology are given.

The methods of forming the working surfaces of the rings of rolling bearings are considered. The influence of the shape of the profile of the rings on the performance characteristics of bearings is shown. The schemes of finishing the rings by superfinishing with profile bars and polishing with an inertial compacted abrasive particles are given. A new technology for improving the quality of the working surfaces of the rings is proposed and the results of experimental studies of the efficiency of ring processing are presented.

This paper presents a novel system integration technical risk assessment model (SITRAM), which is based on Bayesian belief networks (BBN) coupled with parametric models (PM). This model provides statistical information for decision makers, improving risk management of complex projects. System integration technical risks (SITR) represent a significant part of project risks associated with the development of large software intensive systems for defense and commercial applications. We propose a conceptual modeling framework to address the problem of SITR assessment in the early stages of a system life cycle. Initial risks' taxonomy and risks' interrelations have been identified using a hierarchical holographic modeling (HHM) approach. The framework includes a set of BBN models, representing relations between risk contributing factors, and complementing PMs, used to provide input data to the BBN models. In this paper, we present the rationale and the modeling objectives, and describe the concepts and details of BBN experimental model design and implementation. To address practical limitations, heuristic techniques have been proposed for easing the generation of conditional probability tables. PM design principles are described and examples are presented. In conclusion, we summarize the benefits and constraints of SITR assessment based on BBN models. Further research directions and model improvements are also presented. Refereed/Peer-reviewed

This paper presents an approach for modelling Systems Integration Technical Risks (SITR) assessment using Bayesian Belief Networks (BBN). SITR represent a significant part of project risks associated with a development of large software intensive systems.We propose conceptual modelling framework to address the problem of SITR assessment at early stages of a system life cycle. This framework includes a set of BBN models, representing the risk contributing factors, and complementing Parametric Models (PM), used for providing input data to the BBN models. In particular we describe SITR identification approach explaining corresponding BBN models’ topologies and relevant conceptual model framework. This framework includes a set of BBN models, representing the risk contributing factors, fused with complementary PMs providing input data to the BBN models. Heuristic approaches for easing Conditional Probabilities Tables (CPT) generation are described. We briefly discuss preliminary results of model testing. In conclusion we summarise benefits and constraints for SITR assessment based on BBN models, and provide suggestions for further research directions for model improvement. Refereed/Peer-reviewed

Paper presents case study of the evolution of the National Spatial Information Management System (NSIMS). It also describes trade-off analysis approach used to compare different Search Engines for NSIMS. Paper addresses design considerations of the Improved Corporate Search Engine (ICSE) recently developed in Australia. The architecture of the NSIMS has been described, as well as existing search engine capabilities and limitations. Two key areas for search engine improvements have been identified: (1) search context information usage for data relevance criteria application in a search algorithm; (2) user interfaces for entering search requests and query results presentations. Paper presents technical details of ICSE implementation and discussion of characteristics of the proposed improvements in the identified areas. Practical evaluation technique of the search engine efficiency has been proposed and results of trade-off analysis discussed. Paper sections: National Spatial Information System Overview Existing Search Engine Capabilities and NSIMS Limitations The Research Problem and Solution Approach System and Data Analysis Trade-off Study between Existing and Proposed Search Engine Conclusion

The software maintenance burden in military and industrial applications is well known. A variety of factors influence the evolution of large legacy systems, and system upgrades have always been a challenge in terms of avoiding schedule and cost overruns. This evolution becomes even more of a challenge when it is implemented by an organisation other than the original developers. When maintaining complex legacy systems, third party maintenance organisations are placed under additional constraints. Some of these additional constraints come from the decisions made by the Original Equipment Manufacturer (OEM) on the development processes they use and the Computer Aided Software Engineering (CASE) tools that were used to aid in the system development. This paper will describe and analyse a particular case where this occurred with the maintenance of the AP-3C Orion fleet for the Australia Defence Force by Tenix Aerospace and Defence.

The results of the system analysis of the set of input factors of the volumetric centrifugal-planetary processing, allowing to implement a comprehensive approach to the provision of quality processing parameters, are considered. A sequence of modeling processes ensuring the quality of surfaces during bulk processing is given. The results of modeling the contact of an abrasive working body with the surface of a workpiece with a microrelief are shown. The factors determining the stability of reliable achievement of qualitative indicators are noted. A dependence has been developed to determine the parameter of the surface roughness to be reduced, based on the results of modeling the contact between the surfaces of the working fluid and the workpiece by the finite element method. The experience of designing volumetric centrifugal processing operations on the basis of modeling is generalized. Methodical methods of technological preparation of manufacture for volumetric processing are offered.

The paper suggests an experimental methodology for analysing the performance of Web File Servers in terms of throughput and Client-Server path instability. The experimental results preview the network performance for a Client user in Australia and the influence of interconnecting networks and file server traffic demand for download applications.

Modern computer systems are becoming more powerful and complex. This growth in system complexity results in corresponding increase of system integration process (SIP) complexity. System integration (SI) phase of system development life cycle (SDLC) has the highest risks in system development, and is critical for system of systems (SOS) development. This paper examines the research efforts of research community in SI conceptual modelling. The potential risk factors associated with SI are identified, analysed and classified to form taxonomy. One of the recommended and helpful strategies for alleviating the SI risks relates to increase attention to potential integration issues throughout the life cycle. Based on the reviewed literature examples the paper explores cause-and-effect relationships of the specific system's quality attributes and SIP complexity. Those attributes are thoroughly addressed at every development phase starting from requirements, system architecture design, detailed software design and development, design for integration. The paper focuses primarily on technical aspects of SIP. Refereed/Peer-reviewed