Integrated product and process development in collaborative virtual engineering environment

Članak prikazaje integrativni pristup u primjeni virtualne inženjerske tehnologije u oblikovanju proizvoda i proizvodnih procesa za njihovu proizvodnju. To je rezultiralo integracijom CAD/CAM/CAE, tehnologija virtualne stvarnosti u oblikovanju proizvoda, FE/FV numeričke simulacije i optimizacije proizvodnih procesa, kao što je digitalna izrada prototipova proizvoda i procesa, s jedne strane, i tehnike brze izrade proizvoda kao izrada fizičkih prototipova, s druge strane. Reverzni inženjering i koordinatna metrologija također su primijenjeni u reinženjeringu procesa oblikovanja lima postojećih proizvoda, s ciljem generiranja inicijalnih digitalnih informacija o proizvodu i konačne kontrole kvalitete na višesenzorskom koordinatnom mjerenom stroju.The paper presents integrative approach in the application of virtual engineering technologies in design of products and production processes for their manufacture. This has resulted in the integration of CAD/CAM/CAE and Virtual Reality technologies in product design and FE/FV numerical simulations and optimization of production processes as digital prototyping of products and processes on one side, and rapid prototyping techniques as physical prototyping, on the other side. Reverse engineering and coordinate metrology have been also applied in reengineering of sheet metal forming process of existing products, with the aim of generating initial digital information about product and final quality control on multi-sensor coordinate measurement machine

Optimizacija i primena gasno-difuzione protočne injekcione metode za određivanje hlorida

A selective and sensitive procedure for the fast and indirect determination of chloride by the gas-diffusion FIA method has been optimized and applied for the determination of chloride in water samples which contained different amounts of the analyte. The examined samples were: seawater, tap water and very pure water from the water-steam system of the power plant "Nikola Tesla B" in Obrenovac. Application of an amperometric detector (model LC-17A; BAS, West Lafayette, USA) enables the detection limit to be decreased down to 0.05 mu mol/dm(3) of chloride, which col responds to 35.5 pg, and adjustment of the acceptor flow rate and direction inside the gas-diffusion unit. In this way the optimized FIA system has excellent repeatability. For 5 mu mol/dm(3) it was found to be 1.11% (n = 5). The throughput of this method is 60 samples per hour.Selektivan i osetljiv postupak za brzo, indirektno određivanje hlorida gasno-difuzionom metodom otpimizovan je i primenjen za određivanje hlorida u uzorcima voda sa vrlo različitim sadržajem ove vrste: morskoj, vodi za piće i vrlo čistim vodama u sistemu voda-para TE "Nikola Tesna B" u Obrenovcu. Upotreba amperometrijskog detektora tipa LC-17A omogućava snižavanje granice detekcije na 0.05 μmol/dm3 hlorida (što za uzorak zapremine 0.2 cm3 iznosi 35.5 pg) i podešavanje brzine i smera toka u gasno-difuzionoj jedinici. Ovako optimizovan protočni sistem ima odličnu reproduktivnost. Za hloridni standard koncentracije 5 μmol/dm3 relativna standardna devijacija iznosi 1.11 % (n = 5)

Kardiopulmonarna metastrongiliodoza pasa i mačaka doprinos za postavljanje dijagnoze

Background. In the last fifteen years on the European continent and also worldwide, the prevalence of cardiopulmonary metastrongyloidosis in dogs and cats has increased significantly, especially cases involving those parasites which are the most important for veterinary practice (Angiostrongylus vasorum, Aelurostrongylus abstrusus and Crenosoma vulpis). Scope and Approach. The aim of this study is to present a detailed clinical-parasitological approach to highlight the importance of these helminths, and to display the newest findings concerning the diagnostic possibilities in dogs and cats Key Findings and Conclusions. The effects of global warming, vector range shift, the frequent transportation and movement of animals to other epizootic areas, as well as the intensification of merchandise transportation and movement of people are just some of the potential factors which could impact the dynamics of incidence, upkeep and spread of cardiopulmonary nematodoses in carnivores. For the timely implementation of effective treatment of sick animals, it essential to accurately diagnose these parasitoses. Accurate, timely diagnosis can, in the end, significantly contribute to the prognostic course of disease in infected carnivores. Cardiopulmonary metastrongyloidoses in dogs and cats have great clinical-parasitological significance because of their high degree of pathogenicity, their spread outside endemic areas, the difficulties encountered in establishing their diagnosis, and the fact that they represent a potential danger to human health.Uvod. U poslednjih petnaest godina, na evropskom kontinentu i širom sveta značajno se povećala prevalencija kardiopulmonalnih metastrongilidoza kod pasa i mačaka, naročito onih uzročnika koji imaju najveći značaj za veterinarsku praksu (Angiostrongylus vasorum, Aelurostrongylus abstrusus i Crenosoma vulpis). Cilj i pristup. Cilj ovog rada je da se detaljnim kliničko-parazitološkim osvrtom istakne značaj ove grupe helmintoza i da se prikažu najnovija saznanja vezana za mogućnosti njihove dijagnostike kod pasa i mačaka. Ključni nalazi i zaključak. Efekti globalnog zagrevanja, pomeranje granica habitacije vektora, učestalo kretanje i transport životinja u druga epizootiološka područja, intenziviran promet robe i velika fluktuacija ljudi, samo su neki od potencijalnih faktora koji bi mogli uticati na ovakvu dinamiku pojavljivanja, održavanja i širenja kardiopulmonalnih nematodoza kod mesojeda. Za blagovremeno sprovođenje efikasnog tretmana obolelih jedinki neophodna je precizna dijagnostika ovih parazitoza, što u krajnjem ishodu značajno može uticati na prognostički tok oboljenja kod inficiranih mesojeda. S obzirom na stepen njihove patogenosti, poteškoće koje se javljaju u postavljanju dijagnoze, kao i činjenicu da neke od njih predstavljaju potencijalnu opasnost po zdravlje ljudi, navedena oboljenja imaju izuzetan klinički i epizootiološki značaj

Electrochemical Synthesis, Structure Elucidation and Antibacterial Evaluation of 9a-aza-9a-chloro-9a-homoerythromycin A

Electrochemical synthesis, structure elucidation and antibacterial evaluation of 9a-aza-9a-chloro-9a-homoerythromycin A were carried out. It was found that the anodic oxidation of 9a-aza-9a-homoerythromycin A via electrogenerated reactive chlorine species leads to the chlorination of lactam nitrogen in high yield provided the pH of the reaction mixture is maintained above 3. NOESY spectra reveal the existence of the mixture of two conformational families in the solution, the "folding-out" conformer being slightly more abundant comparing to 9a-Aza-9a-homoerythromycin A. The chlorine substitution of lactam hydrogen resulted in improved antimicrobial potency against Sreptococcus pyogenes PSCB0542, Moraxella catarrhalis ATCC 25238, Haemophilus influenzae ATCC 49247 and Enteroccocus faecalis ATCC 29212

Simultano inženjerstvo utemeljeno na virtualnoj proizvodnji

U radu je razmatran koncept konkurentnog inženjeringa koji podrazumijeva simultane aktivnosti u integriranom razvoju proizvoda i procesa, kroz primjenu inovativnih tehnologija virtualnog inženjeringa, posebno u dijelu simulacije proizvodnje, tzv. virtualne proizvodnje. Cilj je da se minimiziraju projektne izmjene u kasnijim fazama projektiranja, a time i vrijeme i troškovi projektiranja proizvoda i pripadajućih procesa. Primjena FE/FV simulacija može eliminirati skupe fizičke prototipove i eksperimente. Vrijeme razvoja se drastično smanjuje, više projektnih alternativa se može provjeriti, što rezultira povećanjem kvalitete. Primjena koncepta ilustrirana je brojnim primjerima numeričkih simulacija proizvodnih procesa korišćenjem SIMUFACT.forming softvera: oblikovanje debljih limova, kovanje, "net-shape" obrada, toplo istiskivanje profila, itd

Respiratorna kapilarioza pasa i mačaka - klinički, parazitološki i epidemiološki značaj

Respiratory capillariasis is a disease of domestic and wild carnivores as well as of people, caused by nematode Eucoleus aerophilus syn. Capillaria aerophila, which lives as a parasite in mucosa of trachea, bronchi and bronchioles, rarely in nasal and frontal sinuses of the host. This parasite has either direct or indirect development cycle which includes optional transition hosts - earthworms. Clinical picture is manifested in the form of a very severe respiratory disease, which is accompanied by an increased bronchovesicular sound, sneezing, gasping and chronic dry cough. Despite the fact that this nematode is widespread in all the parts of the world, that it causes a disease followed by a severe clinical picture and has a zoonotic potential as well, it has been insufficiently investigated and moreover from clinical and parasitological aspect it has not been given enough attention so far. The reason for this is the fact that C. aerophila had been considered to be a strain of very low level of pathogenicity causing only sporadic respiratory infections in dogs and cats. The interest of scientific community for this parasitosis increased the moment when its causative agent spread outside the endemic areas. From the standpoint of monitoring and health protection of both carnivores and peorle, knowledge of basic epizootiological and epidemiological characteristics of these nematodes is of crucial importance, having in mind that its prevalence has significantly increased in dogs and cats in the last ten years, both in Europe and worldwide.Respiratorna kapilarioza je oboljenje domaćih, divljih mesojeda i ljudi, prouzrokovano nematodom Eucoleus aerophilus syn. Capillaria aerophila, koja parazitira u mukozi traheje, bronhija i bronhiola, retko u nazalnim i frontalnim sinusima domaćina. Parazit ima direktan ili indirektan razvojni ciklus, u koji su uključeni fakultativni prelazni domaćini - kišne gliste. Klinička slika se manifestuje u vidu vrlo teškog respiratornog oboljenja, koje je praćeno pojačanim bronho-vezikularnim šumom, kijanjem, hroptanjem i hroničnim suvim kašljem. I pored toga što je rasprostranjena u skoro svim delovima sveta, prouzrokuje oboljenje praćeno teškom kliničkom slikom i poseduje zoonozni potencijal, ova nematodoza nije dovoljno istražena, a sa kliničko-parazitološkog aspekta joj nije posvećeno dovoljno pažnje. Razlog za to je i činjenica, što se dugo smatralo da je C. aerophila vrsta niskog stepena patogenosti i da prouzrokuje respiratorne infekcije pasa i mačaka koje se javljaju sporadično. Interesovanje naučne javnosti za ovu parazitozu se povećalo od onog trenutka, kada se njen uzročnik proširio izvan endemskih područja. Sa stanovišta praćenja i zaštite zdravstvenog stanja mesojeda i ljudi, od izuzetnog je značaja poznavanje osnovnih epizootiološko-epidemioloških karakteristika ove nematodoze, čija se prevalencija značajno povećala u poslednjih deset godina, kod pasa i mačaka kako u Evropi, tako i širom sveta

Mogućnosti prevencije gingivitisa u toku terapije fiksnim ortodontskim aparatima

Introduction: During orthodontic treatment, the risk of gingivitis, periodontal disease and dental caries is increased. For good gingival health during orthodontic therapy, patients must be educated about the importance of daily oral hygiene and also given instructions on plaquecontrol techniques and how to use plaque removal devices properly. Objectives: The aim of this study was to present risk factors for gingivitis during treatment with fixed orthodontic appliances as well as methods and resources for prevention of this widespread disease. Conclusion: Maintaining proper oral hygiene is of great benefit not only for gingival health but also for the success of orthodontic treatment and maintenance of treatment results. Beside healthy gingiva, favorable habits in oral hygiene remain life-long.Pacijenti u toku terapije fiksnim ortodontskim aparatima su pod povećanim rizikom za nastanak oboljenja gingive, parodoncijuma i za nastanak karijesa. Da bi se tokom terapije fiksnim ortodontskim aparatima očuvalo zdravlje gingive pacijente treba informisati o važnosti svakodnevnog održavanja oralne higijene i obučiti pacijente kako da koriste sva dostupna sredstva za održavanje oralne higijene. Cilj rada: Cilj rada je da prikaže faktore koji utiču na nastanak gingivitisa tokom tretmana fiksnim ortodontskim aparatima, kao i metode i sredstva koje se koriste za sprečavanje nastanka ovog rasprostranjenog oboljenja. Zaključak: Uspostavljanje navike pravilnog održavanja oralne higijene je velike koristi ne samo za očuvanje zdravlja gingive već i za uspešnost celokupnog ortodontskog tretmana i očuvanje postignutih rezultata terapije. Osim očuvanja zdravlja gingive, navika održavanja oralne higijene ostaje za ceo život