Computer-based Assistive Technologies in Education for Students with Disabilities

The aim of this paper is to accentuate the role of computer-based assistive technologies in the education process of students with disabilities. The paper presents preferred assistive technologies and types of educational problems that disabled students face. Impact of assistive technologies on independence in education and on quality of studying was also analyzed. Since the focus of this paper lies on the usability of computer-based assistive technologies, as fundamental elements of the education of disabled students, the importance of their accessibility is being particularly emphasized

Patterns-based Information Systems Organization

The socio-technical systems research paradigm is about the complexity of real situations. It confronts us with the quest for variables that could provide us with insight into the behavior of such systems. Their behavior emerges according to internal system properties and adaptation of the system to external conditions. In our view, behavioral patterns are one of those particular variables since machines can recognize them and their dynamics. Based on the synthesis of three different theoretical frameworks, this paper proposes a concept of patterns- based information system organization. The authors built the concept on the Deacon discussion of theory of information, Hofkirchner’s unified information theory and related system behavior, and Kelso’s explanation of pattern creation processes in self-organizing systems. All three researchers have included patterns in their theoretical proposal. According to this analysis of the existing theories and their synthesis, we conclude that in order to design machines that can automatically support new behavior, we have to analyze humans and machines as a complex whole with dynamic relationships and emerging patterns as a dependent variable of behavior. By developing this theoretical concept, we establish a departure point for future research and search for different variables that correlate with pattern formation

Istraživanje učinka alkalne hidrolize otpada životinjskog porijekla kao predtretmana proizvodnji bioplina

Waste is one of the key issues of the modern civilisation and represents the result of our way of life. After the occurrence of bovine spongiform encephalopathy and the ban to feed animals with bone meals, new technologies of animal waste processing are developed, as well as animal waste uses for energy purposes. Certain parts of this waste, such as brains and spinal cord, are deemed high-risk substances and can be infected with prions; their treatment is therefore only possible in strictly controlled conditions. Tests against effects of hydrolysis were conducted on samples of first class animal waste, bovine brains, in circumstances of different temperatures and hydrolisation duration, using the designed and built experimental laboratory reactor for alkaline hydrolysis. Production of hydrolysed substance biogas is monitored using the existing laboratory biogas circuit. Large potentials of hydrolyzates utilisation for energy purposes is featured by the analysis and systematisation of quantified results of the research, and the method used can be successfully applied for the pre-treatment of high-risk biological substances in biogas production.Otpad je jedan od ključnih problema moderne civilizacije i predstavlja rezultat našeg načina života. Nakon pojave goveđe spongiformne encefalopatije, te zabrane hranjenja životinja mesnim koštanim brašnom razvijaju se nove tehnologije prerade životinjskog otpada i njegova upotreba u energetske svrhe. Neki dijelovi ovog otpada, kao mozak i leđna moždina, visoko su rizične tvari i mogu biti zaraženi prionima, te je njihovo zbrinjavanje moguće isključivo u strogo kontroliranim uvjetima. Pomoću osmišljenog i izgrađenog eksperimentalnog laboratorijskog reaktora za alkalnu hidrolizu provedena su ispitivanja učinaka hidrolize pri različitoj temperaturi i trajanju hidroliziranja na uzorcima prve kategorije otpada životinjskog podrijetla, mozgu goveda. Korištenjem postojećeg laboratorijskog bioplinskog sklopa praćena je proizvodnja bioplina hidroliziranog materijala. Analizom i sistematizacijom kvantificiranih rezultata istraživanja istaknut je velik potencijal energetske upotrebe hidrolizata te se korištena metoda može uspješno primijeniti za predtretman visoko rizičnih bioloških materijala pri proizvodnji bioplina

Ispitivanje zavarljivosti čelika TStE 420 nakon simulacije toplinskog ciklusa zavarivanja

The paper presents a short description and overview of the weld thermal cycle simulation methods. An experimental investigation on the weld cycle simulated specimens is predicted by a plan of experiment using single cycle simulation. The obtained hardness results are compared with double cycle simulated specimens results of individual points in the heat-affected zone. Beside that, the characteristic microstructures of points in the heat-affected zone after a single weld thermal cycle simulation are given. A thermal simulation method is suitable for different weldability examinations. In this paper, the authors would like to investigate the maximal hardness of individual points in the weld joint what is important when considering cold cracking sensitivity.U radu se daje kratak opis i pregled metoda simulacije toplinskog ciklusa zavarivanja. Planom eksperimenta je predviđeno eksperimentalno istraživanje na toplinski cikliranim uzorcima. Mjerenjem dobiveni rezultati tvrdoće nakon jednostruke simulacije toplinskog ciklusa u zoni utjecaja topline su uspoređeni s rezultatima nakon dvostruke simulacije toplinskog ciklusa. Pored toga, u radu su prikazane karakteristične mikrostrukture pojedinih točaka u zoni utjecaja topline nakon jednostruke simulacije toplinskog ciklusa zavarivanja. Simulacija toplinskog ciklusa je prikladna za različita ispitivanja zavarljivosti, a u ovom su radu autori željeli istražiti maksimalno očekivane tvrdoće pojedinih točaka u zoni utjecaja topline što je važno kod razmatranja osjetljivosti prema hladnim pukotinama

Scientific Conferences as a Medium of Academic Communication – a Case of INFuture

Scientific conferences provide opportunities for both formal and informal communication of academic insights among conference participants and make possible the sharing of those insights with the wider academic community as well as the wider public through the publication of conference papers in both print and digital form, and owing to all this they may be considered a significant medium of academic communication. Every system of communication consists of three basic elements: source of information, information user(s) and mediums or channels used for disseminating information. We analysed the system of academic communication using this basic structure, where we approached scientific conferences as a medium used for the dissemination of information. However, it is important to emphasise that in this basic scheme researchers represent the source of information and information users at the same time. Our analysis of academic communication includes both the dissemination and assimilation of scientific information taking place at conferences. Standard forms of activity and interaction at scientific conferences, ranging from oral communication during the giving of presentations, through written communication involved in the publication of papers as part of conference proceedings to one’s very presence at a conference, should carefully be evaluated in terms of their effectiveness as mediums of academic communication. We will present the results of our preliminary research through demonstrating correlations between the number of authors and number of papers presented at previous INFuture conferences, classifying authors by country, co-authorship, etc., and thus provide an introduction into a more detailed research into the communication space created as a result of scientific conferences and the role of that space in the communication within a particular academic community. A more extensive research project will include scientometric and bibliometric analyses, interviews and comparative analyses that should provide us with insights into the significance of conferences as a medium of academic communication and their impact on the academic community

Međukristalna korozija raznorodnog austenitnog zavara

Research on influence of heat treatment parameters by annealing (temperature and time duration) as well as quality of austenitic stainless steel weld joint of dissimilar steel on degree delta ferrite transformation (measured by device for ferrite content measuring dr.Foerster type 1.053) and inter-granular corrosion rate using Huey test ( ASTM A 262 part C). A pair of basic materials quality in accordance with standards ASTM A387Gr.12 and ASTM A 240 TP 304L was welded by SMAW using austenitic consumable material different quality. Factors plan of experiment 33 has been applied i.e. temperature 650,700,750ºC; time duration 0,2,10 hours and welds quality AWS E309L, AWS E316L, AWS E 308L.Provedena su istraživanja utjecaja parametara toplinske obradbe žarenjem (temperature i vremena trajanja ) te vrste austenitnog korozijski postojanog zavarenog spoja raznorodnih čelika na stupanj transformacije delta ferita ( mjereno uređajem za određivanje sadržaja ferita dr.Foerster tip1.053) i brzinu međukristalne korozije putem Huey testa (ASTM A 262 partC). Par osnovnih materijala kakvoće sukladne normama ASTM A387gr.12 i ASTM A240 TP 304L je zavarivan REL postupkom primjenom austenitnog dodatnog materijala različite kakvoće. Primijenjen je faktorski plan pokusa 33 tj. varirane su razine temperature toplinske obradbe žarenjem 650, 700,750ºC, kao i vrijeme trajanja toplinske obradbe 0,2,10sati te kakvoća zavarenog spoja raznorodnih čelika AWS E309L, AWS E316L, AWS E 308L

Modelling of Dross Height in Plasma Jet Cutting Process of Aluminium Alloy 5083 Using Fuzzy Logic Technique

Dross height is an important cut quality characteristic in plasma jet cutting process. It can be defined as molten metal blown from the cutting zone and localized on the bottom of the metal sheet. In each plasma jet cutting process, it is important to obtain dross free cuts. Aluminium is as material very present in shipbuilding and metal industry and because of that very usually cut by plasma jet. Because of high heat and electrical conductivity of aluminium, plasma jet cutting is followed by insecurity about process parameters settings that lead to optimal cut quality characteristics. The aim of this paper is to develop a fuzzy logic model that predicts the influence of variable process parameters on dross height in plasma jet cutting of aluminium alloy 5083. Experiments were performed according to Taguchi L27 orthogonal array by varying cutting speed, arc current and cutting height as input process parameters. Fuzzy logic model was defined using Mamdani inference system. This model was used to investigate effects of variable process parameters on dross height response. In order to analyse interaction effects of plasma jet cutting process parameters on dross formation 3D surface and contour plots were generated. The analysis revealed that the cutting speed has the most significant effect followed by arc current and cutting height. Obtained results of this research indicate that artificial intelligence technique, fuzzy logic, can be effectively used for modelling and prediction of dross formation in plasma jet cutting process of aluminium alloy

Approach to determining weldability of steel

U radu su prikazani čimbenici koji utječu na zavarljivost, s posebnim osvrtom na zavarljivost mikrolegiranih čelika i čelika za poboljšavanje. Provedena su ispitivanja simulacijom toplinskog zavarivačkog ciklusa na simulatoru tipa Smitweld TCS 1405, te metodama Implant i Tekken u svrhu utvrđivanja sklonosti mikrolegiranih i poboljšanih čelika hladnim pukotinama. Na koncu su predloženi parametri zavarivanja koji pretpostavljaju zavareni spoj bez hladnih pukotina.The paper presents the factors that affect weldability, with special reference to the weldability of micro-alloyed and quenched and tempered steel. Tests were carried out by simulating the weld thermal cycle simulator type Smitweld TCS 1405, and methods of Implant and Tekken for the purpose of determining the propensity of micro-alloyed and quenched and tempered steel cold cracking. At the end of the proposed welding parameters which assume welding connection without cold cracks

Ispitivanje zavarljivosti čelika TStE 420 nakon simulacije toplinskog ciklusa zavarivanja

The paper presents a short description and overview of the weld thermal cycle simulation methods. An experimental investigation on the weld cycle simulated specimens is predicted by a plan of experiment using single cycle simulation. The obtained hardness results are compared with double cycle simulated specimens results of individual points in the heat-affected zone. Beside that, the characteristic microstructures of points in the heat-affected zone after a single weld thermal cycle simulation are given. A thermal simulation method is suitable for different weldability examinations. In this paper, the authors would like to investigate the maximal hardness of individual points in the weld joint what is important when considering cold cracking sensitivity.U radu se daje kratak opis i pregled metoda simulacije toplinskog ciklusa zavarivanja. Planom eksperimenta je predviđeno eksperimentalno istraživanje na toplinski cikliranim uzorcima. Mjerenjem dobiveni rezultati tvrdoće nakon jednostruke simulacije toplinskog ciklusa u zoni utjecaja topline su uspoređeni s rezultatima nakon dvostruke simulacije toplinskog ciklusa. Pored toga, u radu su prikazane karakteristične mikrostrukture pojedinih točaka u zoni utjecaja topline nakon jednostruke simulacije toplinskog ciklusa zavarivanja. Simulacija toplinskog ciklusa je prikladna za različita ispitivanja zavarljivosti, a u ovom su radu autori željeli istražiti maksimalno očekivane tvrdoće pojedinih točaka u zoni utjecaja topline što je važno kod razmatranja osjetljivosti prema hladnim pukotinama

Heat treatment influence on clad dissimilar joints weakness

Raznovrsni uzorci (ASTM A387 Gr.12 + ASTM A240 TP 304L) platirani različitim postupcima (eksplozijskim zavarivanjem, elektrolučnim postupkom navarivanja pod prahom elektrodnom trakom (EPP) i toplim valjanjem) toplinski su obrađivani (650 °C tijekom 2 sata). Provedena su ispitivanja smične čvrstoće platiranog spoja i Charpy udarne radnje loma. Rezultati ispitivanja su statistički obrađeni te je utvrđena značajnost utjecaja postupka toplinske obradbe na slabljenje platiranog spoja.The dissimilar specimens (ASTM A387 Gr.12 + ASTM A240 TP 304L) clad by different procedures (explosion welding, submerged arc welding–surfacing using strip electrode (SAW) and hot rolling) were heat treated (650 °C through 2 hours). The shear strength testing of clad joints and Charpy impact energy testing were performed. The statistical analysis of testing results was elaborated, and the significance of heat treatment influences on the clad joints weakness was established