67 research outputs found

    Kontaminacija žita aflatoksinima, metabolitima plesni Aspergillus flavus

    Get PDF
    In stored cereals besides other microorganisms, Aspergillus flavus fungi, well known aflatoxin producers, can also be found. When these feedingstuffs, as main material for feed production, are very contaminated with fungi and mycotoxins, they induce different health disturbances both in animals and humans. However, the presence of fungi is not a proof of mycotoxins contamination because thay are produced in specific conditions. By regulating this environmental situation, it is possible to prevent contamination with mycotoxins to a certain extant, as well as their expansion and their threat to health. In this paper results of microbiological and mycotoxicological examinations of 968 cereal samples (corn, wheat, bran, silage, barley, soybean, sorghum) are presented. Samples were sent from different localities in Serbia during 5 years period. At the microbiological examination of cereals it was noticed that 675 samples did not fulfilled legislative requirements regarding fungi content and the biggest difference was present in naturally dried corn. Usually were found Aspergillus spp., Penicillium spp., Fusarim spp., Mucor spp., while A. flavus was present in 154 samples. It was also noticed that aflatoxin was present in 149 samples up to 0,05 mg/kg, what was still in accordance with the actual regulations.Na osnovu rezultata mikrobiološke i mikotoksikološke analize 968 uzoraka žita (kukuruz, pšenica, mekinje, silaža, ječam, soja, sirak) koji su pristizali u ovlašćenu laboratoriju na kontrolu sa teritorije Republike Srbije u toku petogodišnjeg perioda utvrđeno je da sadržaj gljiva (plesni) kod 675 uzoraka žita ne odgovara uslovima Pravilnika o maksimalnim količinama štetnih materija i sastojaka u stočnoj hrani (Službeni list SFRJ, 1990), a najveći stepen odstupanja utvrđen je u prirodno sušenom kukuruzu. Determinacijom gljiva najčešće izolovane vrste su: Aspergillus spp., Penicillium spp., Fusarim spp., Mucor spp., a u 154 uzoraka identifikovano je prisustvo vrste Aspergillus flavus. Ispitivanjem sadržaja aflatoksina, u 149 uzoraka žita, ustanovljen je aflatoksin do koncentracije 0,05 mg/kg (ppm), što je u granicama dozvoljenim važećom regulativom

    Distributed control of manufacturing resources: Security related issues

    Get PDF
    Paradigma industrije 4.0 diktira visoko efikasnu i fleksibilnu proizvodnju uvođenjem konfigurabilnih proizvodnih sistema i resursa koji odlikuju modularnost, interoperabilnost, skalabilnost i mogućnosti komunikacije. Trenutno se širom sveta istražuju različiti pristupi u nastojanju da se dostigne sledeći nivo proizvodnih tehnologija bez ugrožavanja same proizvodnje. Razmatrani pristupi podrazumevaju implementaciju Ciber Phisical Sistem-a, Interneta stvari i generacije proizvodnih sistema Digital Tvins. Složeni industrijski upravljački sistemi, koji su tradicionalno ožičeni i smatraju se sigurnim, sada postaju distribuirani, povezani na internet, obično se zasnivaju na bežičnoj komunikaciji i širom su otvoreni za sve vrste zlonamjernih podviga s potencijalno fatalnim posledicama. U ovom radu predstavljen je pregled bezbednosnih pitanja koja su ključna za razvoj sigurnije bežične distribucije kontrole proizvodnih resursa, pogodnih za izazove u narednim vremenima.Industry 4.0 paradigm dictates highly efficient and flexible production through introduction of reconfigurable manufacturing systems and resources characterized by modularity, interoperability, scalability and communication capabilities. Various approaches are currently researched worldwide in an effort to achieve the next level of production technologies without compromising the production itself. Considered approaches imply implementation of Cyber Physical Systems, Internet of Things and generation of manufacturing systems Digital Twins. Complex industrial control systems, which were traditionally wired and considered safe, are now becoming distributed, internet-connected, usually based on wireless communication and wide open for all kinds of malicious exploits with potentially fatal consequences. This paper presents a review of security related issues that are crucial in developing safer wireless distributed control of manufacturing resources, ADEPT for challenges in coming times

    Prisustvo mikotoksina u smešama za ishranu svinja i živine

    Get PDF
    Mycological and mycotoxicological analysis of many feeding stuffs and complete mashes for different animal species and categories have shown that the feed safety problem has been present for years. It is approved that mouldy feed can contain various mycotoxins, but among them in our conditions the most investigated are aflatoxins, ochratoxins, zearalenone and some trichotecenes. Based on laboratory feed inspection of samples sent to be analysed in the Institute of Veterinary Medicine of Serbia in Belgrade it was concluded that fungi and mycotoxins contamination are common. Primarily presence of zearalenone, ochratoxine and aflatoxin was proven. Although these levels usually do not exceed limits laid by actual legislation, having on mind cumulative effects and possible chronicle exposure of animals to their harmful influence, appropriate and competent approach is necessary. In fact, even when direct loses, as consequence of high mortality are not present, indirect loses due to drop of animal performances and production and occurence of secondary infections must not be neglected.Mikotoksikološkim ispitivanjem uzoraka hrane za živinu i svinje utvrđeno je da je prisustvo mikotoksina veoma aktuelan problem. Pokazalo se da je naročito učestala kontaminacija mikotoksinima prisutna u hrani za svinje, i to u skoro trećini analiziranih uzoraka prevazlazeći maksimalno dozvoljene granice Pravilnikom o maksimalnim količinama štetnih materija i sastojaka u stočnoj hrani (Službeni list SFRJ, 1990). Imajući u vidu kumulativni efekat i moguću hroničnu izloženost životinja štetnom dejstvu mikotoksina i u slučaju nižih koncentracija potrebna je odgovarajuća stručna kontrola. I onda kada se ne manifestuju direktni gubici kao posledica uginjavanja životinja, ne smeju se zanemariti indirektne štete usled pada proizvodnje i pojave sekundarnih oboljenja

    Distributed control of manufacturing resources: Security related issues

    Get PDF
    Paradigma industrije 4.0 diktira visoko efikasnu i fleksibilnu proizvodnju uvođenjem konfigurabilnih proizvodnih sistema i resursa koji odlikuju modularnost, interoperabilnost, skalabilnost i mogućnosti komunikacije. Trenutno se širom sveta istražuju različiti pristupi u nastojanju da se dostigne sledeći nivo proizvodnih tehnologija bez ugrožavanja same proizvodnje. Razmatrani pristupi podrazumevaju implementaciju Ciber Phisical Sistem-a, Interneta stvari i generacije proizvodnih sistema Digital Tvins. Složeni industrijski upravljački sistemi, koji su tradicionalno ožičeni i smatraju se sigurnim, sada postaju distribuirani, povezani na internet, obično se zasnivaju na bežičnoj komunikaciji i širom su otvoreni za sve vrste zlonamjernih podviga s potencijalno fatalnim posledicama. U ovom radu predstavljen je pregled bezbednosnih pitanja koja su ključna za razvoj sigurnije bežične distribucije kontrole proizvodnih resursa, pogodnih za izazove u narednim vremenima.Industry 4.0 paradigm dictates highly efficient and flexible production through introduction of reconfigurable manufacturing systems and resources characterized by modularity, interoperability, scalability and communication capabilities. Various approaches are currently researched worldwide in an effort to achieve the next level of production technologies without compromising the production itself. Considered approaches imply implementation of Cyber Physical Systems, Internet of Things and generation of manufacturing systems Digital Twins. Complex industrial control systems, which were traditionally wired and considered safe, are now becoming distributed, internet-connected, usually based on wireless communication and wide open for all kinds of malicious exploits with potentially fatal consequences. This paper presents a review of security related issues that are crucial in developing safer wireless distributed control of manufacturing resources, ADEPT for challenges in coming times

    An open architecture control system for multi‐axis wood CNC machining center

    Get PDF
    Abstract: This paper presents an open architecture control system for multi‐axis wood computer numerical control (CNC) milling machining centre, based on LinuxCNC. The wood CNC machining system is supported by an equivalent virtual machine in a CAD/CAM environment, as well as in the control system. Simulation within virtual environment is essential for multi‐axis machining, and the developed virtual machines are used for program verification and monitoring of the machining process. The virtual machine in the programming system allows the verification of the program before it’s sent to the actual machine, while the virtual machine in the control system represents the final verification of the program, as well as the process monitoring system. Configuration of the control system and implementation of virtual machines will be shown, along with the conducted machining experiments that ensued after the successful simulation on developed virtual machines

    Indicators of inflammation and proteasis/antiproteasis system and their relation to lung function and clinical caracteristics of patients with chronic obstructive pulmonary disease

    Get PDF
    Uvod/Cilj: Hronična opstruktivna bolest pluća (HOBP) predstavlja značajan javno zdravstveni problem u celom svetu jer su njena učestalost i posledice u stalnom porastu, naročito u zemljama sa značajnom populacijom pušača. Procene oboljevanja za 2010.godinu su ukazale na 384 miliona slučajeva HOBP uz godišnji mortalitet od 2,9 miliona ljudi [1-3]. Hronična opstruktivna bolest pluća (HOBP) se karakteriše ograničenjem protoka vazduha koje nije potpuno reverzibilno. Ograničenje protoka vazduha je obično progresivno i udruženo sa poremećenim inflamacijskim odgovorom pluća na štetne čestice ili gasove [4,5]. Pacijente obolele od HOBP odlikuje stanje pojačane inflamacije i oksidativnog stresa, pojačane proteolize ekstracelularnog matriksa i neravnoteže u proteaza/antiproteaza sistemu, uz prateće patomorfolološke promene u smislu destrukcije alveola i remodelovanje disajnih puteva. Multikomponentna priroda bolesti podrazumeva pored patoloških promena u disajnom stablu i plućima, i sistemske efekte sa zahvatanjem drugih organskih sistema: kardio-vaskularnog sistema, mišića i kostiju, metabolizma, kognitivnih svojstva i raspoloženja. Cij ovog istraživanja je bio da se ispitaju nivoi pokazatelja sistemske inflamacije i sistema proteaza/antiproteaza i utvrdi njihova povezanost sa pokazateljima plućne funkcije i kliničkim karakteristikama pacijenata sa hroničnom opstruktivnom bolesti pluća. Metod: Ovim istraživanjem su bili obuhvaćeni svi pacijenti sa dijagnozom hronične opstruktivne bolesti pluća koja je postavljena prema GOLD kriterijumima (engl. Global Initiative for Chronic Obstructive Disease - GOLD) [1]) i lečeni su u periodu od maja 2017.godine do januara 2018.godine na Odeljenje za astmu, HOBP i hroničnu respiracijsku insuficijenciju Klinike za pulmologiju KCS. Učestvovalo je ukupno 98 ispitanika, starijih od 40 godina, pušači i bivši pušači, u stabilnoj fazi bolesti, bez drugog respiratornog oboljenja. Kontrolnu grupu je činilo 47 zdravih ispitanika uparenih po polu i godinama. Na pregledu je učinjeno ispitivanje plućne funkcije: spirometrija, difuzijski kapacitet za ugljen-monoksid (CO), telesna pletizmografija...Introduction / Aim: Chronic Obstructive Pulmonary Disease (COPD) is a significant public health issue with a constant increase in disease incidence, especially in countries with a significant population of smokers. Predictions for year 2010 were 384 million cases of COPD with an annual mortality of 2.9 million people [1-3]. Chronic obstructive pulmonary disease (HOBP) is characterized by a limitation of airflow that is not completely reversible. The limitation of airflow is usually progressive and associated with an abnormal inflammatory response to the fumes or gases [4,5]. Patients with COPD are characterized by a state of increased inflammation and oxidative stress, enhanced extracellular matrix degradation and imbalance in the proteasis/antiproteasis system, with accompanying pathomorphologic changes of alveolar destruction and airway remodeling. Multicomponent nature of the disease includes pathological changes in the respiratory tract, as well as systemic effects with the involvement of other organ systems: cardio-vascular system, osteosceletal, metabolism, cognitive properties. The aim of this study was to asses the levels of systemic inflammation and the possible imbalance in protease / antiprotease system and to determine their relation to lung function parameters and clinical characteristics of patients with COPD. Method: This study included all patients diagnosed with COPD according to the Global Initiative for Chronic Obstructive Disease (GOLD) [1], and treated in the period from May 2017 to January 2018 in the Department of Asthma, COPD and chronic respiratory insufficiency in the Clinic for pulmonology, Clinical center of Serbia, Belgrade. Study included 98 subjects, aged 40 and over, smokers and former smokers, in a stable phase of COPD, with no other respiratory disease. Healthy control group included 47 subjects. All subjects completed pulmonary function testing (spirometry, diffusion capacity for carbon monoxide (CO), and body plethysmography), COPD Assessment Test (CAT) and the mMRC dyspnoea scale..

    Procedure for definition of end-effector orientation in planar surfaces robot applications

    Get PDF
    Razvoj moćnih metoda za programiranje robota koje su ujedno i korisnički prilagođene je tema značajnih istraživanja u robotskoj zajednici. Radi olakšavanja programiranja robota, pojavljuje se ideja o razvoju standardnih procedura za programiranje najčešće prisutnih robotskih zadataka, a koje se mogu univerzalno lako upotrebiti kao gotov deo (ready-made) korisničkog programa. Važna klasa aplikacija industrijskih robota podrazumeva kretanje hvatača (end-effector) u paralelnim ravnima. U ovom radu je prikazan razvoj procedure jezika za programiranje robota koja služi za određivanje normale ravni objekta u odnosu na koordinatni sistem od značaja, kao i osnova procedure za automatizovani postupak programiranja orijentacije hvatača u odnosu na ravan objekta. Ova procedura se može koristiti kao integralni deo task oriented metoda programiranja robota, a takođe kao i procedura eksplicitnog robotskog programskog jezika, i ilustrovana je kroz praktični primer na robotu Lola 15.Design of user-friendly and at the same time powerful robot programming methods is the subject of significant efforts undertaken by the international robotics community. For the purpose of facilitating robot programming, with regard to the most common present-day applications in industry, it would be useful to develop programming procedures for frequently used manipulator tasks which could be easily implemented and used as ready-made application software. Important class of industrial robot applications involves end-effector trajectories in planar surfaces. Development of robot programming language procedure intended for determination of object plane normal with respect to frame of interest, as well as programming of end-effector orientation is presented in this paper. This procedure can be used as integral part of task oriented robot programing applications as well as a procedure for explicit programming languages, and it is illustrated in practical example with the robot Lola 15

    Procedure for definition of end-effector orientation in planar surfaces robot applications

    Get PDF
    Razvoj moćnih metoda za programiranje robota koje su ujedno i korisnički prilagođene je tema značajnih istraživanja u robotskoj zajednici. Radi olakšavanja programiranja robota, pojavljuje se ideja o razvoju standardnih procedura za programiranje najčešće prisutnih robotskih zadataka, a koje se mogu univerzalno lako upotrebiti kao gotov deo (ready-made) korisničkog programa. Važna klasa aplikacija industrijskih robota podrazumeva kretanje hvatača (end-effector) u paralelnim ravnima. U ovom radu je prikazan razvoj procedure jezika za programiranje robota koja služi za određivanje normale ravni objekta u odnosu na koordinatni sistem od značaja, kao i osnova procedure za automatizovani postupak programiranja orijentacije hvatača u odnosu na ravan objekta. Ova procedura se može koristiti kao integralni deo task oriented metoda programiranja robota, a takođe kao i procedura eksplicitnog robotskog programskog jezika, i ilustrovana je kroz praktični primer na robotu Lola 15.Design of user-friendly and at the same time powerful robot programming methods is the subject of significant efforts undertaken by the international robotics community. For the purpose of facilitating robot programming, with regard to the most common present-day applications in industry, it would be useful to develop programming procedures for frequently used manipulator tasks which could be easily implemented and used as ready-made application software. Important class of industrial robot applications involves end-effector trajectories in planar surfaces. Development of robot programming language procedure intended for determination of object plane normal with respect to frame of interest, as well as programming of end-effector orientation is presented in this paper. This procedure can be used as integral part of task oriented robot programing applications as well as a procedure for explicit programming languages, and it is illustrated in practical example with the robot Lola 15

    Failure prediction of gas and oil drilling rig pipelines with axial defects

    Get PDF
    Working conditions of casing pipes in drilling rigs can significantly influence the initiation and development of damage in the material, and therefore also the safe service of the entire system. In this work, an integrity assessment of a steel pipe with initial defect (machined surface crack) is presented. The position of this defect is on the external surface; unlike transport pipes, where internal surface is often endangered due to the contact with the fluid, casing pipes are often exposed to damages at the external surface. Analyzed crack is in axial direction, bearing in mind that this type of defect most significantly decreases the load carrying capacity of the cylindrical pressurized components. A pipe segment exposed to internal pressure is analyzed experimentally and numerically, using the finite element method. The experimental setup included the tracking of crack mouth opening displacement (CMOD) values, as well as J integral, which is determined by application of direct measurement. Criteria for pipe failure are determined on finite element models of the pipe; fracture initiation and plastic collapse are considered as failure mechanisms. The size of the crack is varied in the finite element models; several 3D models with different crack sizes (length and depth) are evaluated. Dependence of maximum internal pressure on the defect size is obtained. 2D plane strain models are also examined, with an aim to determine the applicability limits of this simplified approach. Based on the obtained results, integrity assessment criteria for the analyzed geometries are discussed

    Determination of optimal parameters for rapid prototyping of the involute gears

    Get PDF
    Nowadays, rapid prototyping technologies are available at very affordable prices. This is the main reason why they are being used in almost all industry sectors. 3D printers are currently being widely used for rapid prototyping and development of the new products. However, taking into account the permanent progress of rapid prototyping materials mechanical characteristics (usually different kinds of plastics), 3D printers are sometimes used even for production of the failed parts replacements - operating at the low load and rotational speed conditions. This is the main goal of this paper - to establish optimal 3D printing parameters (printing direction, layer height and percent of infill) which will allow printed gears to replace failed steel gears, for at least some time, enough for spare steel gears to be produced and delivered on site. Taking into account previously mentioned facts, the application of the 3D printed gears can potentially provide the reduction of maintenance delays in different industrial facilities (factories, workshops, etc.) which will consequently lead to significant energy and financial savings
    corecore