A new peak detector based on usage of CCCIIs

Peer Reviewe

Opšti pristup održavanju motora, sa aspekta radnih fluida poljoprivredne i druge mehanizacije u cilju produženja veka i racionalne eksploatacije

Every IC engine is designed and produced with an intention to enable the planned lifetime to be as long as possible. The lifetime is influenced by numerous factors such as reputation of designers and producers, the choice and realization of technical methods and materials, manner of exploitation, using adequate working mediums (lubricants, fuels, liquid coolants, additives etc.) and other factors. The application of appropriate mediums in exploitation and their required change may significantly influence the extension of the IC engines and its components lifetime. However, the improper application of the mediums or low quality application and / or prolonged change time may cause a reduction in expected engine lifetime and increasing of toxic components in exhaust emission. In this paper a general approach is given to analyses of significant factors of oil quality, liquid coolant quality and other additives quality and the influence of these factors on the maintenance and lifetime of agricultural and other mechanization engines in order to enhance rational exploitation, as well as a global approach is given to actual possibilities in exhaust emission control.Svaki motor, projektovan je i proizveden sa težnjom da planirani vek trajanja bude što duži. Na dužinu tog veka, utiči mnogobrojni faktori, pre svega renome projektanta i proizvođača, zatim, izbor i realizacija tehnoloških postupaka i materijala, način eksploatacije, primena adekvatnih radnih mediuma (maziva, goriva, rashladnih sredstava, aditiva i dr.) i drugi faktori. Primena odgovarajućih mediuma u eksploataciji i njihova predviđena zamena u znatnoj meri mogu uticati na produženje veka motora, odnosno njihovih komponenata. Međutim, njihova neadekvatna primena, ili primena niskog kvaliteta, kao i neodgovarajućim produženjem intervala zamene, može doprineti smanjenju očekivanog veka trajanja motora i povećanju štetnih komponenata emisije izduvnih gasova. U ovom radu je dat jedan opšti prikaz uticajnih faktora kvaliteta ulja, rashladnog fluida i drugih aditiva na održavanje i vek motora poljoprivredne i druge mehanizacije, a u cilju racionalne eksploatacije, kao i jedan globalni pristup aktuelnim mogućnostima smanjenja emisije izduvnih gasova

Reproductive Parameters and Birth Type Influence on Sanska Goat Kids Body Weight

In this paper Sanska goat reproductive parameters after the first kidding are shown as well as influence of birth type on kid body weight at birth. At first insemination average age of young goats was 252 days. Average gestation period for goats that carried twins was 150.19 days and for goats that carried singles 151.10 days. Determined difference in gestation length of 0.91 days in favor of goats that carried singles was not statistically significant (P0.05). Goat fertility after first kidding was 164.70%. Kid body weight at birth was analyzed based on birth type (singles-twins). Singles had higher body weight at birth than twins by 0.91kg (34.60%) which was statistically very significant (P<0.01). Average body weight of singles was 3.54kg, and twins 2.63kg, twins were approximately 74.29% of body weight of singles. Gender based differences at birth in body weight were present in favor of male kids, but they were not statistically significant (P0.05). Based on obtained results in this research we can conclude that the results which were obtained for researched parameters are within average limits for Sanska goat breed

Predictability modulates the affective and sensory-discriminative neural processing of pain

Knowing what is going to happen next, that is, the capacity to predict upcoming events, modulates the extent to which aversive stimuli induce stress and anxiety. We explored this issue by manipulating the temporal predictability of aversive events by means of a visual cue, which was either correlated or uncorrelated with pain stimuli (electric shocks). Subjects reported lower levels of anxiety, negative valence and pain intensity when shocks were predictable. In addition to attenuate focus on danger, predictability allows for correct temporal estimation of, and selective attention to, the sensory input. With functional magnetic resonance imaging, we found that predictability was related to enhanced activity in relevant sensory-discriminative processing areas, such as the primary and secondary sensory cortex and posterior insula. In contrast, the unpredictable more aversive context was correlated to brain activity in the anterior insula and the orbitofrontal cortex, areas associated with affective pain processing. This context also prompted increased activity in the posterior parietal cortex and lateral prefrontal cortex that we attribute to enhanced alertness and sustained attention during unpredictability. (c) 2006 Elsevier Inc. All rights reserved.This study was supported by grants from The Swedish Research Council (2003-5810), The family Hedlund Foundation and Karolinska Institutet. The project was finished in the context of Stockholm Brain Institute.info:eu-repo/semantics/publishedVersio

Analiza trenda razvoja transmisija traktora sa aspekta poboljšanja vučno-dinamičkih karakteristika

Within the period of almost a hundred years of tardition, developmental concept of transmissions of agricultural tractors has gradually been brought into accord with engine power, tractor mass, velocity of movement and other requests, with the purpose of finding permanent improvements of pulling and dynamic characteristics, and all that with the view to optimizing agricultural and technical conditions and increasing the degree of rationalization of production. In the first phases of development of tractor transmissions shafting from engine was effected through gradual gearbox and main gearing to driving wheels. In further decades of development of trnsmission systems, more and more attention was paid to the development of gearbox gearings particularly in the increase of gear shift. In that way, optimal solution, i. e. the ideal pulling hyperbola, was nearer and nearer. In tadey, s trend of development of tractor transmissions so-called automatic transmissions have an ever increasing application, providing a continual shafting depending on conditions of operation. Tractors fitted with such types of transmissions have a much higher degree of power utilization, i. e. more favourable potential pulling characteristic. In this work a short review is given of the analysis of agricultural tractors transmission from the aspect of improvement of pulling and dynamic characteristics.Koncept razvoja transmisije poljoprivrednih traktora kroz skoro stogodišnju tradiciju vremenom se usklađivao sa snagom motora, masom traktora, brzinom kretanja i drugim zahtevima, u cilju iznalaženja permanentnih poboljšanja vučno-dinamičkih karakteristika, a sve u cilju optimiranja agrotehničkih uslova i povećanja stepena racionalizacije proizvodnje. U prvim fazama razvoja traktorskih transmisija snaga od motora se prenosila preko stepenastog menjača i glavnog prenosnika do pogonskih točkova. U daljim decenijama razvoja transmisionih sistema, sve veća pažnja se posvećivala razvoju menjačkih prenosnika, pre svega u povećanju broja stepena prenosa. Na taj način sve više se prilazilo optimalnom rešenju, odnosno približavalo idealnoj hiperboli vuče. U današnjem trendu razvoja transmisija traktora sve veću primenu imaju tkz. automatske transmisije koje obezbeđuju kontinualni prenos snage u zavisnosti od uslova eksploatacije. Traktori opremljeni sa takvim tipovima trasmisija imaju znatno veći stepen iskorišćenja snage, odnosno povoljniju potencijalnu vučnu karakteristiku. U ovom radu dat je kratak osvrt analize razvoja transmisije poljoprivrednih traktora, sa aspekta poboljšanja vučno dinamičkih karakteristika, odnosno potencijalne vučne karakteristiketr taktora

Biomasa iz poljoprivrede kao potencijani izvor alternativnih goriva pogonskih agregata

Liquid fossil fuels are the dominant fuel for the plant, as means of all forms of transport, employment and agricultural machines and aggregates. In the coming period is unrealistic to expect more intense and massive development, implementation, construction of new engines that would be adapted to another type of fuel. All efforts have been focused on finding such a fuel that could be adapted to existing engine structures, and to simultaneously satisfy additional criteria related to ecology, as well as reliability and privacy. In this context, biofuel is given increasing attention, which can be produced from renewable primary and secondary agricultural raw materials, with generally positive effects of performance, reliability, emissions and thus protect the environment, as well as other requirements that the current fossil fuel backgrounds meet. As biofuels can be considered methanol, biometanol, bioethanol, biodiesel, natural gas, hydrogen and others. Raw materials from agricultural biomass to produce alternative fuels could be: sugar cane, sugar beet, corn sorghum, corn, wheat, rapeseed, sunflower, potatoes, barley, olive, palm, sweet potato, monioka, Jerusalem artichokes (topinambur) and others. Products and residues from forest mass: wood, pulp, paper, black lug and others. Now it different kinds of waste such as municipal and secondary waste, food wastes, wastes from production of cereals and food, etc.., With the current use of fossil origin fuel from oil, coal, oil shale, natural gas and others. The paper gives a brief review of possible fuel from biomass, which can be, with its advantages and disadvantages, potential use as fuel internal combustion engines.Tečna fosilna goriva su najdominantnija goriva za pogon, kako sredstava svih vidova saobraćaja, tako i poljoprivrednih radnih mašina i agregata. U narednom periodu je nerealno očekivati intenzivniji i masovniji razvoj, u primeni, novih konstrukcija motora koje bi bile prilagođene nekoj drugoj vrsti goriva. Svi napori su usredsređeni na pronalaženju supstitucije goriva, koje bi bilo prilagođeno postojećim konstrukcijama motora, a da istovremeno zadovolje i dodatne kriterijume vezane za obnovljivost, ekologiju, pouzdanost korišćenja i dr. U tom kontekstu, biogorivima se posvećuje sve veća pažnja, koja se mogu proizvesti iz obnovljivih primarnih i sekundarnih poljoprivrednih sirovina, sa generalno pozitivnim efektima performansi, pouzdanosti, emisije izduvnih gasova, a time i zaštite životne sredine, kao i drugim zahtevima koje sadašnja goriva fosilnog porekla ispunjavaju. Kao biogoriva mogu se razmatrati metanol, biometanol, bioetanol, biodizel, prirodni gas, vodonik i dr. Sirovine iz poljoprivredne biomase za proizvodnju alternativnih goriva mogu biti: šećerna trska, šećerna repa, sirak šećerac, kukuruz, pšenica, uljana repica, suncokret, krompir, ječam, maslina, palma, batata, monioka, jerusalemska artičoka (topinambur) i dr. Iz proizvoda i ostataka šumskih masa: drvo, celuloza, papir, crni lug i dr. Zatim iz različitih vidova otpada, kao što su: komunalni i sekundarni otpad, otpadi iz proizvodnje žitarica i hrane i dr., uz sadašnju primenu goriva fosilnog porekla iz: nafte, uglja, uljnih škriljaca, prirodnog gasa i dr. U radu je dat kraći prikaz mogućih vrsta goriva iz biomase, koja se mogu, sa svojim prednostima i manama, potencijalno koristiti kao pogonsko gorivo motora SUS

Radijalne zaptivače - uloga i značaj u održavanju mašina

Appropriate choice of sealing elements is one of essential tasks of sealing related with problem of working fluids loosening. In that way cost of maintenance are decreasing and reliability of machinery couples is improving. Radial sealers are used for sealing of different types of axles and shafts, primary in motor and vehicles industries as well as productions of machinery and equipment. This paper presents basical types of radial sealers with accent on material type used for their production, physical and chemical factors of material properties as well as some tribology characteristics. Influence of working conditions on strength of radial sealers is also shown as well as reliability on chemical reagents.Pravilan izbor zaptivnih elemenata kvalitetno rešava problem gubitka radnog fluida što je jedan od suštinskih zadataka zaptivanja. Na taj način smanjuju se troškovi održavanja a povećava pouzdanost mašinskih sklopova. Radijalne zaptivače se koriste za zaptivanje kod različitih osovina i vratila, prvenstveno u motornoj i vozilskoj industriji, mašinskoj industriji, industriji opreme. U radu su prikazane osnovne vrste radijalnih zaptivača, pri čemu je naglasak dat na vrste materijala koji se koriste za njihovu izradu, uticaj fizičko-hemijskih faktora na osobine materijala, kao i neke tribološke karakteristike. Takođe, prikazan je i uticaj radnih uslova na izdržljivost radijalnih zaptivača, kao i postojanost na hemijske reagense

Razmatranje potrošnje motornog ulja dizel motora

From aspect of regulation strict ecological regulations of exgsauts emissions from diesel engines as well imroving maintenace of diesel enigine, today reducing of consumption from motor lubricant is primary goal in construction of engine. In that way important role in that feature is researching in the level of consumption of oil and influencing factors. Date obtained in this field give consumers the costs of exploitation using adequate engine lubricant for certified engine. In this paper work it is evaluated problem of consumption of engine lubricant from several influencing parameters like construction of engine, condition of exploitation and quality parameters of measured lubricant.Sa aspekta zadovoljenja strogih ekoloških propisa izduvne emisije dizel motora kao i poboljšanja dizel motora sa stanovišta održavanja, danas smanjenje potrošnje motornog ulja predstavlja jedan od primarnih zadataka konstruktora motora. U tom kontekstu značajno mesto zauzima istraživanje nivoa potrošnje motornog ulja i uticajnih faktora. Rezultati istraživanja daju smernice i korisnicima koji mogu da projektuju troškove eksploatacije koji su ogledaju u korišćenju odgovarajućeg motornog ulja za odgovarajući motor. U radu je razmatran problem potrošnje motornog ulja sa stanovišta uticaja konstrukcije motora, uslova eksploatacije, kao i parametra kvaliteta motornog ulja

Oscilatorne pojave kod poljoprivrednih traktora

When considering the basic aspect of ergonomic requests for the purpose of improving general comfort of tractor is very complex. Besides base ergonomic requests, (noise, mikroklimate, visibilty, air contamination to favour to handl and etc.), are qurentitatve oscilatory loads on tractor operator are very important. In IMR Institute comprehensive me asurements of acceleration of vertical vibrations on table tests add have been carred out on one type tractor, manufacturing IMR on diferent measure ments points and operating regimengine. In the contex, along with the given review of a part of obtained results, the analysis of vibratory acceleratiopns of tested seats of steeping wheel has been made from the aspect of meeting ISO standard criteria and out standard.Osnovni aspekt ergonomskih zahteva u cilju poboljšanja opšte komfornosti rukovaoca traktora je veoma kompleksan. Pored osnovnih ergonomskih zahteva (buka, mikroklima, vidljivost, pogodnost rukovanja komandama, aerozagađenje i dr.), veoma su značajna i kvantitativna oscilatorna opterećenja rukovaoca traktora. U Institutu IMR-a izvršena su opsežna merenja vertikalnih vibracija na dizel motoru na probnom stolu, i na jednom tipu traktora iz svog proizvodnog programa, na različitim mernim mestima i režimima rada motora. U tom kontekstu, dat je prikaz dela dobijenih rezultata i analiza vibratornih ubrzanja na mernim mestima kao i sedištu rukovaoca traktora sa aspekta zadovoljenja kriterijuma ISO standarda, kao i vanstandardnih ispitivanja