Jednym z głównych naturalnych źródeł rtęci w środowisku jest aktywność wulkaniczna. Emisja rtęci wynikająca z działalności wulkanicznej może stanowić aż do 78% całkowitej ilości rtęci emitowanej ze źródeł naturalnych.
Ośrodek Badawczo-Rozwojowy Ster w Swadzimiu jest jedną z czołowych europejskich instytucji zajmujących się projektowaniem, przeprowadzaniem badań oraz opracowywaniem technologii produkcji foteli stosowanych w pojazdach środków komunikacji zbiorowej (kolejnictwo, tramwaje, autobusy, mikrobusy). Ośrodek generuje nowe rozwiązania stosowane następnie na masową skalę w zakładach produkcyjnych firmy Ster Sp. z o. o. w Poznaniu oraz w Szamotułach.
Intensywność przyspieszania i hamowania w zmiennych warunkach stanu nawierzchni i różnych temperaturach otoczenia i drogi jest zdeterminowana interakcją opona-nawierzchnia. Uzyskiwany w zadanych warunkach współczynnik przyczepności warunkuje zdolność do przekazywania sił i momentów na drogę. Powoduje to również, iż kierowca musi się przystosować do warunków panujących na drodze aby w sposób zaplanowany i bezpieczny się po niej poruszać. W artykule przedstawiono wyniki badań doświadczalnych cech kinematycznych ruchu pojazdu w warunkach drogi pokrytej warstwą ubitego śniegu.
EN
The intensity of acceleration and deceleration under varying road conditions and different ambient temperatures and the road is determined by the tire-pavement interaction. The resulting in selected circumstances coefficient of friction determines the ability to transmit forces and moments on the road. It also means that the driver needs to adjust to the conditions on the road to making a planned and safe to navigate. This paper presents the results of experimental kinematic characteristics of the vehicle under the road covered with a layer of compacted snow.
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Przedstawiono wyniki badań, a także rozważania teoretyczne pomocne do bardziej obiektywnego wyznaczania parametrów ruchu pojazdów, które stanowią jeden z wyznaczników doboru metod budowy lub wykonywania prac remontowych warstwy ścieralnej nawierzchni, zapewniających optymalne cechy przyczepności samochodów osobowych, a tym samym zwiększenie bezpieczeństwa w ruchu drogowym.
EN
Presented are the test results as well as theoretical aspects, which might contribute to unbiased estimation of the vehicle movement parameters, which, among others, are usually taken into consideration for selection of the road wearing course building or repair projects for optimum passenger car tractive adhesion and thus, higher traffic safety.
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Tyres friction traces shapes constitute the basic input parameter for computer simulations of movement reconstruction before and after vehicle collision. Traces often include encoded, possible to readout, information concerning movement dynamics of a car that was marking them. This information may concern also both if the vehicle was intensively braked or not, and what trajectory it was moving before or after arriving the place of collision. In this paper there are presented two selected cases of reconstruction of real road accidents for which issuing of uncompromising opinion and ruling would not be possible without previous identification of tyres traces outlines on the roadway.
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Kinematic features describing the curvilinear track of vehicle make significant problem in analysis of braking, accelerating and also arc driving processes. Recognized features of motion during measurement can be used in analysis of instantaneous values of accelerations, speeds and covered path. Research of the curvilinear track on road generating are oriented for come to know parameters for vehicle movement in given conditions and type of road. In testing grounds were used special measuring device making possible linkage of motion parameters of vehicle with geometrical features formed by track. The paper describes measuring device for three-dimensional canvassing and archiving of motion parameters of vehicle and also presents comparative analysis of the curvilinear contour of track from tyre with vehicle trajectory motion.
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There were presented the results of computational simulations of curvilinear and three- dimensional motion of vehicle, which were done with software for a reconstruction of road accidents. The paper also presents the results of real experiments, which were performed with a motor-car. The values of acceleration and angular velocity were the results of simulation. These results were generated for a coordinate system of vehicle and used for further analysis. In case of real vehicle, the above mentioned parameters of motion were measured with three-axial accelerometer sensors with piezogyroscopes from Analog Devices company - these sensors were mounted on the vehicle roof. Simulation data was used to create and verify the transformation method of acceleration from the vehicle coordinate system to the global coordinate system of a position of mass centre of vehicle. The results obtained from this method were correct. Next the attempt of performing of the similar transformations for the results of measurement of real motion of vehicle with a set of sensors was done. The obtained results of simulations and experiments were compared. The reasons of discrepancy between obtained results were shown.
W artykule zestawiono niektóre rodzaje urządzeń, służących do pomiarów parametrów ruchu pojazdów, mierzących w sposób bezpośredni różne wielkości fizyczne. Omówiono sposób rejestracji danych przez czujniki przyspieszeń z elektronicznymi żyroskopami, stosowanymi między innymi w samochodowych "czarnych skrzynkach". Przeprowadzona została analiza sygnałów z ww. czujników, poprzedzona badaniami symulacyjnymi i eksperymentalnymi. W przypadku obu rodzajów badań, podejmowano próby odtwarzania toru ruchu środka masy samochodu, na podstawie uprzednio wyznaczonych (w symulacyjnym programie komputerowym) lub zmierzonych (w rzeczywistym eksperymencie) przyspieszeń i prędkości kątowych. Wyniki badań wskazały na istniejące obecnie ograniczenia w zakresie stosowania czujników do odtwarzania parametrów ruchu pojazdów, co uzasadnia konieczność prowadzenia dalszych poszukiwań w celu wyjaśnienia przyczyn oraz minimalizację zaobserwowanych błędów.
EN
In the paper there were compared some of the types of devices used for measuring vehicles movement parameters, which in direct way measure various physical parameters. There was discussed, how data are registered by acceleration sensors with electronic gyroscopes, used among others in the automotive "black boxes". There was carried out the signal analysis from above mentioned sensors, followed by making simulation and experimental research. For both types of studies, there were made the attempts to reconstruct the motion of the mass center of a car, on the basis on pre-assigned (in a simulation computer program) or measured (in a real experiment) acceleration and angular velocity values. The results indicated the existing restrictions in usage of sensors to make reconstruction of vehicle movement parameters, justifying the need for further research to clarify the causes and minimize the observed errors.
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The paper presents the comparative analysis of contact roughness between friction surfaces of brake pads, which were fastened to the bicycle frame, and friction surfaces of the element of the wheel rim. The following temporary hypothesis was formulated: on the basis of the measured geometry of the surface irregularities of the elements, it is possible to determine which rim surface cooperated with the left and right brake pad. The proposed method of comparison of the roughness profiles of the frictional braking elements can be useful and appropriate for analyzing some types of vehicle accident reconstructions.
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Reconstruction of accidents of automotive vehicles, including motorcycles, requires an analysis and determination of parameters of their movement before collision. Cases when accelerated motorcycles have accidents take place. Based on increased number of high speed motorcycles and lack of information about their traction possibilities there were conducted researches, which the main aim was characteristic of maximum parameters of motion of these vehicles. In paper there were presented the results of performed researches of accelerations of sports motorbike Honda CBR 900 RR. Experiment was used for analysis of process of acceleration with partition to a few characteristic phases of motion.
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Possibility of speed reducing with high intensity is one of the most significant dynamic parameters conditioning usage safety of vehicles in road traffic. Although cars' braking effectiveness was broadly recognized and described (Dudziak, 2002; Gaca, 2002; Gillespie, 1992; Ślaski et al., 2001), but there are considerable difficulties with finding information concerning motorcycle braking effectiveness. In this elaboration there are presented results of braking of sport motorcycles Honda CBR 900RR (sport motorcycle of high engine cubic capacity and high horsepower) and Junak Millenium (motorcycle rated to two-wheel vehicles class type cruiser). Results of carried out road tests were registered with measuring system of our own design based on acceleration sensors and piezogyroscope. During tests, motorcycles were accelerated and then broken with maximal possible to obtaining deceleration.
The role of TTI is an effective supporting the use of transport network for example, in order to improve the capacity and to shorten travel time, delays, fuel consumption. In the time of increasing traffic congestion on the road network, especially on EU freight corridors and in cities, the RDS-TMC deliver the alternatives and it facilitate traveller information by providing powerful travel planning tools. Establishing a national RDS-TMC system is the goal for Poland not only because approaching EURO 2012 but mainly to join to other European countries and as they enjoy the benefits of TMC service. All actions must be supported by the agreement of all players in the information chain which creating the TMC service: ministerial bodies, civil/public services, public road authorities, public broadcasters, road users and industry. Only clear and transparency system of responsibility for maintenance and overseeing could guarantee the high reliability and correct work of TMC service.
Changes in the act on Public Roads and some other acts are intended to implement in Polish law the provisions of European Parliament Directive 2006/38/EC on fee collection for use of some types of infrastructure by heavy vehicles. According to the bill submitted to the Polish Parliament (Sejm) by the government, the vignette system was to cease to operate on 1st July 2008. After the works undertaken by Infrastructure Commission some changes was introduced to the bill to the act on public roads. The main changes concern maintain the vignettes up to the half of 2011 and introducing the electronic fee system from 1st July 2011, also rise the vignette charges to stabilise the NRF’s budget for next three years. The paper present the evolution of legislative path accompanied constructing motorways in Poland.
Przedstawiono wyniki badań eksperymentalnych hamowania samochodu osobowego, wyposażonego w system ABS i opony letnie, na trzech różnych nawierzchniach. Dokonano wstępnej analizy efektywności hamowania według kryterium rodzaju nawierzchni. Badania zostały wykonane w maju 2004 r. w ramach współpracy Katedry Podstaw Kontrukcji Maszyn Politechniki Poznańskiej i Ośrodka Badawczo-Rozwojowego Przemysłu Oponiarskie-go Stomii w Poznaniu.
EN
The results of experimental research of passenger car equipped in ABS system with summer tyres on three different road surfaces braking process were presented. Initial analysis of efficiency of this process was executed according to kind of road surface criterion. The research were executed by Poznań University of Technology, the Chair of Basics of Machine Design and the Research and Developing Centre of the Tyre Industry OBRPO Stomil in Poznań, in May 2004.
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Here is presented the method of stereometric measurements of wearing surface replicas of road pavement using coordinate, optical measuring technique. In this elaboration there was discussed the analysis of roadway roughness basing on roughness coefficients such as: amplitude, hybrid, functional and connected with analysis of material fraction curve. There was pointed out the purposefulness of introduction of new techniques to measurements of road pavement roughness. Some feats of road pavement surface roughness were identified, those which have the biggest influence on characteristic of tire - road pavement mating. Elaborated method can be used to analysis of optional three-dimensional porous surfaces.
An analysis was carried out focusing on geometric properties and load conditions of structural components made of zirconium oxide (96% of zirconium dioxide partially stabilised by 4% yttrium oxide). The examined components are used in dentistry for implantation of artificial teeth. The above sinter is electrically and magneticaly non-conductive and is chemically inert. The surface geometry and mechanical strength properties were investigated under various load conditions. The new design of implant support is characterised by high strength comparable with that for high quality steel.
PL
Dokonano analizy cech geometrycznych i stanu obciążenia elementów konstrukcyjnych wykonanych z tlenku cyrkonu, stosowanych w technice stomatologicznej do implantowania sztucznego uzębienia. Zbadano geometrię powierzchni oraz cechy wytrzymałościowe w różnych stanach obciążenia. Nowa konstrukcja wspornikowa implantów cechuje się wysokimi własnościami wytrzymałościowymi o porównywalnych cechach stali wyższej jakości.
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