Na osnovi poznavanja dimenzijskih značajki skidera s vitlom (osnovne dimenzije, masa vozila, položaj točke težišta), razvijen je model procjene kretnosti skidera za privlačenje drva uz nagib terena ...na siguran, djelotvoran i okolišno prihvatljiv način. Model je zasnovan na graničnom nagibu kretnosti skidera temeljem vučne značajke vozila, koji povezuje dva istraživačka pristupa, 1) vozilo – teren (raspodjela sila ovisno nagibu i vučenom teretu) te 2) kotač – tlo (procjena vučnih značajki skidera temeljem indeksa kotača), uz poštivanje niza ograničenja proisteklih iz prethodnih istraživanja: i) rasterećenja prednje osovine vozila, ii) preopterećenja stražnje osovine vozila, iii) najmanje uzdužne stabilnosti skidera, iv) najmanje nosivosti šumskog tla te v) dopuštenog opterećenja pneumatika.
Rezultati simulacijskog modeliranja procjene kretnosti skidera s vitlom Ecotrac 55V opremljenoga pneumaticima 12.4-24 pri privlačenju drva uz nagib terena, značajno se razlikuju s obzirom na uvjete nosivosti podloge te masu vučenih tereta. Kod manjih tereta, mase do 1 tone, kretnost skidera određuju kriteriji/ograničenja graničnoga nagiba kretnosti vozila (vučna značajka) i okolišne pogodnosti (najmanja nosivost podloge). Porastom težine tereta, osim nosivosti šumskog tla, odlučujući ograničavajući čimbenik kretnosti postaje odnos opterećenja prednje i stražnje osovine vozila (>1 : 3,5), koji ograničava kretnost skidera na terene nagiba <33 % kod tereta od 1,5 tone, tj. <20 % kod tereta od 2 tone. Kod tereta od 2,5 tone, na kretnost skidera, utječu kriteriji najvećeg dopuštenog opterećenja stražnje osovine skidera na nagibima <7 %.
Based on the dimensional characteristics of the cable skidder (dimensions, weight, position of the center of gravity), a model was developed for estimating the mobility of the skidder during timber extraction (skidding) uphill in a safe, efficient and environmentally sound way. The model is based on the limiting slope of skidders’ mobility depending on the traction performance of the vehicle, which connects two research approaches, 1) vehicle – terrain (distribution of forces depending on the slope and load) and 2) wheel – soil (traction performance based on wheel numeric). The model is in compliance with a number of restrictions arising from previous research: i) unloading the front axle of the vehicle, ii) overloading the rear axle of the vehicle, iii) minimum longitudinal stability of the skidder, iv) minimal soil bearing capacity and v) allowed tyre load capacity.
The results of the mobility of the cable skidder Ecotrac 55V equipped with 12.4-24 tires during skidding timber uphill, differ significantly with regard to the load-bearing capacity and the load size. For smaller loads, weighing up to 1 ton, the mobility of the skidder is determined by the criteria/limits of the skidder gradeability (traction performance) and environmental benefits (minimum load-bearing capacity). As the weight of the load increases, apart from the load-bearing capacity, the decisive limiting factor of mobility becomes the load ratio of the front and rear axles of the vehicle (> 1: 3.5), which limits the mobility of the skidder on slopes <33% for loads of 1.5 tons, <20% for 2 tons. At a load of 2.5 tons, the mobility of the skidder is affected by the criteria of the maximum allowable load of the rear axle of the skidder on slopes <7%.
Insurgent citizenships have arisen in cities around the world. This book examines the insurgence of democratic citizenship in the urban peripheries of São Paulo, Brazil, its entanglement with ...entrenched systems of inequality, and its contradiction in violence. James Holston argues that for two centuries Brazilians have practiced a type of citizenship all too common among nation- states--one that is universally inclusive in national membership and massively inegalitarian in distributing rights and in its legalization of social differences. But since the 1970s, he shows, residents of Brazil's urban peripheries have formulated a new citizenship that is destabilizing the old. Their mobilizations have developed not primarily through struggles of labor but through those of the city--particularly illegal residence, house building, and land conflict. Yet precisely as Brazilians democratized urban space and achieved political democracy, violence, injustice, and impunity increased dramatically. Based on comparative, ethnographic, and historical research, Insurgent Citizenship reveals why the insurgent and the entrenched remain dangerously conjoined as new kinds of citizens expand democracy even as new forms of violence and exclusion erode it. Rather than view this paradox as evidence of democratic failure and urban chaos, Insurgent Citizenship argues that contradictory realizations of citizenship characterize all democracies-- emerging and established. Focusing on processes of city- and citizen-making now prevalent globally, it develops new approaches for understanding the contemporary course of democratic citizenship in societies of vastly different cultures and histories.
Za prikupljanje prostornih podataka većih zahvata u prostoru sve se više upotrebljavaju metode izmjere terena koje su ekonomski isplativije te ne zahtijevaju predugački vremenski rok za realizaciju ...projekta. Cilj ovog članka bio je analizirati visinsku točnost službenoga DMR-a Republike Hrvatske dobivenog fotogrametrijskom restitucijom, kao primjer takvog tipa prostornih podataka. Upravo zbog načina njegova nastanka, to je ujedno i najtočniji službeni DMR Republike Hrvatske prikupljen u gradskim područjima na razini cijele države. Prostorna analiza provedena je na područjima različitih topografskih značajki. Ispitivanje visinske točnosti DMR-a provedeno je ovisno o nagibu terena, izgrađenosti grada i vegetaciji. Visinska točnost DMR-a nastalog fotogrametrijskom restitucijom analizirana je u odnosu na katastarske točke geodetske osnove, terestrička mjerenja te DMV dobiven na osnovi SRTM podataka. Računalna priprema i obrada prostornih podataka provedena je uz pomoć profesionalnih softvera AutoCAD Civil 3D, Global Mapper i QGIS, dok je analiza točnosti i vizualizacija izvedena u programskom paketu ArcGIS. Ovo istraživanje moglo bi se iskoristiti za studije izvodivosti izgradnje sustava odvodnje oborinskih voda te za druge pripremne radove pri izradi geoprostornih projekata na većim zahvatima u prostoru.
Insurgent citizenships have arisen in cities around the world.
This book examines the insurgence of democratic citizenship in the
urban peripheries of São Paulo, Brazil, its entanglement with
...entrenched systems of inequality, and its contradiction in
violence. James Holston argues that for two centuries Brazilians
have practiced a type of citizenship all too common among
nation-states--one that is universally inclusive in national
membership and massively inegalitarian in distributing rights and
in its legalization of social differences. But since the 1970s, he
shows, residents of Brazil's urban peripheries have formulated a
new citizenship that is destabilizing the old. Their mobilizations
have developed not primarily through struggles of labor but through
those of the city--particularly illegal residence, house building,
and land conflict. Yet precisely as Brazilians democratized urban
space and achieved political democracy, violence, injustice, and
impunity increased dramatically. Based on comparative,
ethnographic, and historical research, Insurgent
Citizenship reveals why the insurgent and the entrenched
remain dangerously conjoined as new kinds of citizens expand
democracy even as new forms of violence and exclusion erode it.
Rather than view this paradox as evidence of democratic failure and
urban chaos, Insurgent Citizenship argues that
contradictory realizations of citizenship characterize all
democracies--emerging and established. Focusing on processes of
city- and citizen-making now prevalent globally, it develops new
approaches for understanding the contemporary course of democratic
citizenship in societies of vastly different cultures and
histories.
Nowadays, coherent and conventional supersonic jets are widely used in electric arc furnace (EAF) steelmaking processes. Generally, these jets are installed in the EAF oven wall with a tilt angle of ...35?45?. However, limited studies have been conducted on the impact characteristics of these inclined supersonic jets. This study developed an optimized theoretical model to calculate the penetration depth of inclined coherent and conventional supersonic jets by combining theoretical modeling and numerical simulations. The computational fluid dynamics results are validated against water model experiments. A variable k is newly defined to reflect the velocity variation, which is related to the jet exit at the jet free distance. The results of the optimized theoretical model show that the lance height and lance angle influence the penetration depth of the inclined supersonic jet. At the same lance angle, the penetration depth decreases with the increase in the lance height. Similarly, it decreases with the decrease in lance angle at the same lance height. In addition, the penetration depth of an inclined coherent supersonic jet is larger than that of an inclined conventional supersonic jet under the same conditions. An optimized theoretical model can accurately predict the penetration depths of the inclined coherent and conventional supersonic jets.
I have asked three of the most renowned scholars (Lars Elleström, Lúcia Nagib and Joachim Paech), whose works have had a wide-reaching impact in the field, to explain what drew them to the study of ...intermedial phenomena in the first place and how they see the relevance of intermediality and its most important questions today. I also wanted to find out how their different cultural or theoretical backgrounds have informed their work.
Nagib ramena različit je kod svakog čovjeka jer je on posljedica tjelesne konstitucije, spola, dobi, zanimanja, bavljenja sportom, životnih navika te urođenih ili stečenih anomalija (bolesti). ...Mjerenje stvarnog nagiba ramena važno je za kvalitetnu izradu odjevnog predmeta po mjeri. U tu svrhu izrađen je kutomjer za precizno određivanje nagiba ramena.
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