An initial study of the effects vortex generators (VGs) have on the mitigation of vortex-induced vibrations (VIVs) of hydrofoils have been performed at the Waterpower laboratory of the Norwegian University of Science and Technology. The VGs are placed close to the trailing edge of a blunt hydrofoil. Reasonable design parameters of the VGs were found from the literature with regard to which would induce the strongest vortices with the lowest drag. Vibration frequencies of the hydrofoil were measured using flush mounted strain gauges located close to the trailing edge. This paper presents the design of the VGs and some initial results of the experiments performed with these devices. The preliminary results indicate a possible mitigation of VIVs. This could be because of the interference between the primary vortices generated by the hydrofoil and the longitudinal vortices generated by the VGs, but further work is necessary to make a conclusion.

SUMMARY: Success in artistic gymnastics certainly depends on the morphological characteristics of the athletes, some of which are basic body height and weight. The aim of this study is to determine whether there is a statistically significant difference in body height and weight between the male and female participants on the Olympic Games from 1996 to 2016. The following variables were chosen: body weight (kg), body height (cm). The results did show significant differences between women's artistic gymnastics in body weight and height over a 20-year period. In men's artistic gymnastics we didn't find the difference. This research is important in setting comparative parameters in the selection process and sport specialization regarding morphological characteristics according to different events of gymnasts at the elite level.

The paper presents an online system named REDBUL, which is aimed at reverse engineering of relational databases. REDBUL enables database designers to automatically extract the schema from an existing relational database, and visualize it in a web browser, whereby the extracted schema is represented by the standard UML class diagram. Currently, two relational database management systems are supported by the REDBUL system, MS SQL and MySQL, while the paper illustrates reverse schema engineering for a MySQL database.

Object tracking is one of the fundamental tasks in computer vision. It is used almost everywhere: human-computer interaction, video surveillance, medical treatments, robotics, smart cars, etc. Many object tracking methods have been published in recent scientific publications. However, many questions still remain unanswered, such as, which object tracking method to choose for a particular application considering some specific characteristics of video content or which method will perform the best (quality-wise) and which one will have the best performance? In this paper, we provide some insights into how to choose an object tracking method from the widespread OpenCV library. We provide benchmarking results on the OTB-100 dataset by evaluating the eight trackers from the OpenCV library. We use two evaluation methods to evaluate the robustness of each algorithm: OPE and SRE combined with Precision and Success Plot.

Rails are a part of track structure where corrosion process inevitably occurs, except if they are fully insulated and devoid of contact with any other part of the structure (sleepers, fastening accessories) or electrolyte like moist soil or water in track structure. Corrosion occurs much faster in the presence of stray currents, which very soon results in the loss of material at the rail foot. The paper presents an overview and description of parameters influencing stray current levels, such as electrical potential in rail and longitudinal rail conductivity, rail-to-earth electrical resistance, electrical conductivity of load-bearing concrete layers of truck structure, and electrical conductivity of soil.

Die Standsicherheit historischer Mauerwerksbauten muss nicht nur bei gewöhnlichen Einwirkungen, sondern auch während Naturkatastrophen gewährleistet sein. Die seismische Bestandsbewertung der gründerzeitlichen Bausubstanz in Wien ist ein zentrales Thema in der qualitativen sowie konstruktiven Tragwerksbeurteilung. Obwohl der Mauerwerksbau seit vielen Jahrhunderten Anwendung findet, stellt die realistische Tragwerksbewertung eine hochkomplexe Herausforderung dar. Die nach aktuellen Regelwerken zur Nachbemessung herangezogenen Berechnungsmethoden vermögen nur unzureichend das reale Tragverhalten sowie die mögliche Aktivierung der globalen Versagensmechanismen wiederzugeben. Dies führt dazu, dass vereinfachte Nachweise rechnerisch oftmals nur schwer gelingen und zur Kompensation fragwürdige Verstärkungsmaßnahmen ergriffen werden, obwohl der Altbestand bereits einige Beben erlebt und überwiegend schadfrei überstanden hat. Der vorliegende Beitrag befasst sich mit den aktuell zur Erdbebennachbemessung verwendeten Ansätzen und verfolgt den Zweck, Problempunkte aufzuzeigen und sie einem leistungsfähigen, an Versuchsreihen gestützten Materialmodell zur räumlichen Tragwerksanalyse des historischen Altbestandes gegenüberzustellen. Es wird gezeigt, dass die herkömmlichen Berechnungsmethoden für den gemauerten Altbestand ohne Berücksichtigung der Interaktions‐ und Lastumlagerungseffekte sowie der charakteristischen Konstruktionsweise das reale Tragverhalten nur teilweise abbilden. Die Arbeit soll einen Beitrag zur technischen Fachdiskussion zur Erdbebensicherheit des Altbestandes darstellen sowie die Diskussion zur Formulierung realistischer Berechnungsmodelle beleben.

In this short demo paper, we introduce godash 2.0 godash is a headless HTTP adaptive streaming (HAS) video streaming platform written in the Google programming language GO. godash has been extensively rewritten for this release so as to provide ease of use, and a host of new features. godash includes options for eight different state of the art adaptive algorithms, five HAS profiles, four video codecs, the ability to stream audio and video segments, two transport protocols (TCP and QUIC), realtime output from five Quality of Experience (QoE) models, as well as a collaborative framework for the evaluation of cooperative HAS streaming. In this demo, we will introduce each of the options available in the godash configuration file, and illustrate examples of how to use the collaborative players using both godash on a native machine as well as godash within godashbed. godashbed is an integrated large-scale testbed framework for the evaluation of HAS streaming, which uses a virtual environment to serve video content locally (which allows setting security certificates) through the Mininet virtual emulation tool. In this manner, godash provides a framework for rapid deployment and testing of new HAS algorithms, QoE models and transport protocols.

Introduction: Ventilator associated pneumonia (VAP) is defined as nosocomial pneumonia in patients who have mechanical ventilation (MV) for more than 48 hours. The diagnosis of VAP is based on radiological-microbiological examinations. In the United States, the Centers for Disease Control and Prevention (CDC) and the National Health Care Network (NHSN) have an incidence of VAP of 5.8% per 1,000 days on mechanical ventilator. Aim: In this study, we had an aim to determine the occurrence of ventilator-associated pneumonia (VAP) in patients with MV who were hospitalized in the intensive care unit. Method: The study was retrospective, clinical, conducted in the period from January 1, 2016 until December 31, 2016. In a one-year period, 719 patients of both sex, aged 14 to 91, were hospitalized in the intensive care unit of the Clinic for Anesthesia and Resuscitation of the University Clinical Center in Sarajevo. The study included 250 patients of both sex who had respiratory support with mechanical ventilator. No patient was excluded from the study. As a confirmation of VAP, we used microbiological reports from the patient history documentation. The results were presented statistically through tables and graphs, numerically, by a percentage, and by a mean value with standard deviation. Results: Out of the 719 hospitalized patients, 250 or 34.8% underwent controlled ventilation. In 103 or 41.2% of patients some form of pneumonia was confirmed microbiologically. An average patient age on controlled ventilation was 60.4 ± 16.8 years. The mean age of a female patients who were on controlled ventilation was 63.2 ± 16.7, higher than that of male patients, which was 57.8 ± 16.6 years. The most frequent patients were over 60 years of age (52.8%). The shortest hospitalization of patients on controlled mechanical ventilation was 1 day and the longest was 120 days. Average duration of mechanical ventilation was 6.9 ± 10.5 days. Conclusion: VAP is a relatively common complication in patients with MV that can increase morbidity and mortality, as well as treatment costs. It is more frequent in females and in the elderly. Medical staff should provide normal maintenance of respiratory functions to a patient who is on MV, which will reduce the risk of VAP.

Manufacturers of automated systems and their components have been allocating an enormous amount of time and effort in R&D activities. This effort translates into an overhead on the V&V (verification and validation) process making it time-consuming and costly. In this paper, we present an ECSEL JU project (VALU3S) that aims to evaluate the state-of-the-art V&V methods and tools, and design a multi-domain framework to create a clear structure around the components and elements needed to conduct the V&V process. The main expected benefit of the framework is to reduce time and cost needed to verify and validate automated systems with respect to safety, cyber-security, and privacy requirements. This is done through identification and classification of evaluation methods, tools, environments and concepts for V&V of automated systems with respect to the mentioned requirements. To this end, VALU3S brings together a consortium with partners from 10 different countries, amounting to a mix of 25 industrial partners, 6 leading research institutes, and 10 universities to reach the project goal.

In this paper, we present our work in close-distance non-verbal communication with tabletop robot Haru through hand gestural interaction. We implemented a novel hand gestural understanding system by training a machine-learning architecture for real-time hand gesture recognition with the Leap Motion. The proposed system is activated based on the velocity of a user's palm and index finger movement, and subsequently labels the detected movement segments under an early classification scheme. Our system is able to combine multiple gesture labels for recognition of consecutive gestures without clear movement boundaries. System evaluation is conducted on data simulating real human-robot interaction conditions, taking into account relevant performance variables such as movement style, timing and posture. Our results show robustness in hand gesture classification performance under variant conditions. We furthermore examine system behavior under sequential data input, paving the way towards seamless and natural real-time close-distance hand-gestural communication in the future.

This paper aims to examine the impact of digital tools in mathematics and the readiness of teachers and students applying these interactive tools in teaching. The data used in the research are obtained from the test results of 526 students, in five secondary schools in North Macedonia. The students in this research, are divided into two groups: mainly as a control group and an experimental group. The control group is the group of students who do not have access to the interactive tools at home and who use interactive tools only once a week in the school while the group of students in the experimental group have access to them and have the opportunity to use these interactive applications every day. The students in the control group and the experimental group were selected from the same year and the gender equality of the groups was taken into account. To further understand the relationship between teaching with digital tools and learning after testing was surveyed the participants. The results in our research suggest that interactive teaching tools have a positive impact on the teaching process and increase students' knowledge.