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1
EN
The purpose of this article is to present the results of a preliminary analysis of modern methods for preventing collisions between birds and aircraft. The focus was in particular on methods that enable defining the level of threat in passenger aviation and existing solutions for eliminating these threats. The first section defines the level of the existing threat of collision with birds for civil aviation on the basis of collision statistics based on collision reports submitted by pilots. The second chapter describes normative documents on methods intended to reduce the risk of collisions with birds, such as aviation rules and regulations, passenger aircraft certification, bird detection and deterrence systems, procedures of flight crews and air traffic controllers, and the development of bird detection and deterrence methods. Based on the analysis of existing solutions, the third chapter proposes a block diagram of an on-board system reducing the risk of aircraft collisions with birds by determining the level of collision risk and transmitting information about the risk level to the flight crew in order to reduce the effect of surprise among pilots, improve the accuracy of the statistics and operational safety by carrying out a technical inspection of the aircraft after the collision. The final chapter contains conclusions.
PL
Celem niniejszego artykułu jest przedstawienie wyników wstępnej analizy współczesnych metod przeciwdziałania kolizji statku powietrznego z ptakami. W szczególności skoncentrowano się na metodach, które umożliwiają zdefiniowanie poziomu zagrożenia w lotnictwie pasażerskim oraz istniejących rozwiązaniach eliminacji tych zagrożeń. W pierwszej części zdefiniowano poziom istniejącego zagrożenia kolizji z ptakami dla lotnictwa cywilnego na podstawie statystyk kolizji określonych na podstawie raportów składanych przez pilotów o zaistniałej kolizji. W drugim rozdziale opisano dokumenty normatywne traktujące o metodach umożliwiających ograniczenie ryzyka kolizji z ptakami takie jak zasady i przepisy lotnicze, certyfikacja samolotu pasażerskiego, systemy detekcji i odstraszania ptaków, procedury załóg i kontrolerów lotniczych oraz rozwój metod detekcji i odstraszania ptaków. W trzecim rozdziale na podstawie przeprowadzonej analizy istniejących rozwiązań zaproponowano schemat blokowy systemu pokładowego redukującego zagrożenie kolizji statku powietrznego z ptakami poprzez określenie poziomu zagrożenia kolizji oraz przekazanie informacji o stopniu zagrożenia do załogi lotniczej, w celu zredukowania efektu zaskoczenia u pilotów, poprawienia dokładności statystyk oraz bezpieczeństwa operacji poprzez wykonanie przeglądu technicznego samolotu po kolizji. Ostatni rozdział zawiera wnioski.
EN
The Indosinian orogeny, which was regarded as the collision event between the South China and Indochina blocks that occurred in Southeast Asia, including Vietnam, resulting in the formation of the Indosinian mountain range. However, the question of how many times collision between these blocks occurred in the past and during which period remains unanswered. Furthermore, the closure of the ancient ocean and the evidence of its remnants between the South China and Indochina Blocks are still the subjects of serious debate. The underlying origin of the Indosinian thermo-tectonism is uncertain. The entire region was affected by the thermal-tectonic processes in the west, caused by the collision of the Sibumasu plate and Indochina block. The absence of evidence supporting the Indosinian as a significant mountain-building event is highlighted through an examination of regional paleogeography, as well as palaeontological and thermochronological data. There is no conclusive evidence to suggest that the Indochina and South China blocks collided during the Triassic times. A plate tectonic scenario that describes the Indosinian orogeny as a reactivation event triggered by the accretion of the Sibumasu block to Indochina is favored.
EN
Concrete hollow thin-walled high piers (CHTWHPs) located in mountainous areas may be destroyed by the huge impact force of accidental rocks. The study focuses on analyzing the effects of rock impact on the pier, including its impact force, pier damage, dynamic response, and energy dissipation characteristics. The results show that: (1) Increasing the impact height led to a decrease in the peak impact force. Specifically, 15.5% decrease in the peak collision force is induced when the height of rock collision rises from 10 m to 40 m. (2) The damage mode of the pier’s collision surface is mainly oval damage with symmetrical center, radial damage on the side surface, and corner shear failure on the cross section. (3) The peak displacement of bridge pier increases with the increase of collision height. As the collision height increased from 10 m to 40 m, the bridge pier’s peak displacement also increased, rising by 104.2%. (4) The concrete internal energy gradually decreased with increasing collision height, dropping by 36.9% when the height of rock collision rises from 10 m to 40 m. The reinforcement internal energy showed an increase of 78%. The results of this study may provide reference for the rock collision resistance design of CHTWHPs.
EN
The paper concerns modelling the dynamics of the contact system of the tested sample with an elastic half-space (anvil) during their collision. The original elements in the paper include the proposed general approach to solving the problem of contact dynamics. The presented approach consists in determining the force of impact on the sample during the collision and the joint solution of the problem for the tested sample and the problem for an elastic semi-space under the conditions of the assumptions of Hertz's theory. The resulting interaction forces allow the determination of displacements and stresses.
EN
This article explores the use of ontology for semi-automatic marine vessel navigation and ship-to-ship communication to mitigate collision risk. Semi-automatic vessel communication is a step towards automatic communication for autonomous ships. Examples of how such communication can be used is discussed, based on a comprehensive analysis of selected marine collisions, with particular attention to the communication conducted on ships. The effectiveness of such communication was assessed and compared. The suggested solutions are based on the review of official reports from accident investigations. The novelties of this work include original ontologies and interfaces. Through this work, it could be possible to fully automate communication processes between ships. In future work, the research results in this work will be used to create a system of automatic communications for manned and autonomous vessels.
PL
Na podstawie dwóch zdarzeń drogowych pokazano, jakie są możliwości ustalania prędkości pojazdów przed kolizją z wykorzystaniem analizy nagrań wideo pochodzących z kamer pokładowych i geodezyjnego pomiaru miejsca zdarzenia. Pozyskane informacje pozwoliły na odtworzenie ruchu uczestników kolizji przy wykorzystaniu metody modelowania symulacyjnego, co dało możliwość wskazania na przyczyny kolizji.
EN
On the basis of two road traffic incidents the possibilities of specifying vehicles speeds prior to collision by analysing the video recordings from on-board cameras and geodetic measurements are shown. Owing to the thus obtained data it was possible to reconstruct the movements of the participants of the collisions, using the simulation modelling method, which enabled the identification of the causes of the collisions.
PL
W artykule przedstawiono podstawowe założenia dotyczące zastosowania metodologii BIM oraz modelowania 3D w projekcie tunelu w Świnoujściu. Pokazano praktyczne wykorzystanie modeli 3D oraz nowoczesnych technologii na placu budowy.
EN
The article presented basic assumptions of the BIM methodology and 3D modeling in the tunnel Świnoujście project. There was shown the practical usage of the 3D models and modern technologies on the construction site.
EN
Offshore wind farms are developing well all over the world, providing green energy from renewable sources. The evaluation of possible consequences of a collision involves Finite Element computer simulations. The goal of this paper was to analyse the influence of selected strain-based failure criteria on ship damage resulting from a collision with an offshore wind turbine monopile. The case of a collision between an offshore supply vessel and a monopile-type support structure was examined. The results imply that simulation assumptions, especially the failure criteria, are very important. It was found that, using the strain failure criteria according to the minimum values required by the design rules, can lead to an underestimation of the ship damage by as much as 6 times, for the length of the hull plate, and 9 times, for the area of the ship hull opening. Instead, the adjusted formula should be used, taking into account both the FE element size and the shell thickness. The influence of the non-linear representation of the stress-strain curve was also pointed out. Moreover, a significant influence of the selected steel grade on collision damages was found.
10
Content available remote Uniknięcie zderzenia czołowego przez wykonanie obronnego manewru skrętu w lewo
PL
W artykule przedstawiono wypadek drogowy, w którym dwa auta zderzyły się czołowo prawymi narożnikami. Z materiału osobowego wynikało, że obaj kierowcy wykonali przed zderzeniem obronny manewr skrętu - każdy w swoją lewą stronę. Ten typ zderzenia, jak i zachowanie kierowców było wyjątkowo nietypowe. Jednym z tych pojazdów był radiowóz policyjny, który był pojazdem uprzywilejowanym. W artykule przedstawiono również rozważania dotyczące możliwości rozpoznania pojazdu jako uprzywilejowanego, które były efektem wykonanego eksperymentu.
EN
A road traffic accident in which two cars collided with their front rights comers is described. According to the witnesses’ testimony both drivers performed a defensive turning manoeuvre before the crash - each to his left. This type of collision and the drivers’ behavior were exceptionally unusual. One of the vehicles was a police car, which is an emergency vehicle. Following an experiment, the recognisability of a vehicle as an emergency vehicle is also discussed.
PL
W artykule przedstawiono metodykę obliczania wartości EES na podstawie wyników testów zderzeniowych z dużymi prędkościami. Wskazano możliwości wykorzystania danych z rejestratorów EDR (Event Data Recorder) w rekonstrukcji zderzeń. Porównano wartości współczynników A i B stosowanych w metodzie CRASH3 i wartości EES obliczonych na podstawie testów OMBD (Oblique Moving Deformable Barrier) i standardowych testów NHTSA.
EN
The methodology of calculating EES on the basis of data from crash tests at high speeds is presented. The applicability of data provided by EDR (Event Data Recorder) in collision reconstruction is indicated. The values of coefficients A and B used in the CRASH3 methods and the values of EES based on OMBD (Oblique Moving Deformable Barrier) tests as well as standard NHTSA tests are compared.
PL
Artykuł przedstawia metodę opiniowania zdarzeń drogowych, udokumentowanych zapisem monitoringu, w których istnieje podejrzenie świadomego sprowokowania kolizji przez jednego z uczestników. Rozważania oparto na konkretnym zdarzeniu, w którym taką możliwość sugerowały zarówno dowody osobowe, jak i informacje o uczestniczeniu jednego z kierujących w dużej ilości podobnych zdarzeń drogowych. Pomimo że w przedmiotowej sprawie pytania skierowane do biegłego były sformułowane wyjątkowo ogólnikowo, to w istocie sprowadzały się do ustalenia, czy intencją obwinionego - kierującego, posiadającego pierwszeństwo przejazdu, było sprowokowanie zderzenia w okolicznościach wskazujących na odpowiedzialność drugiego uczestnika zdarzenia za jego wystąpienie. Oczywistym jest, że bezpośrednia odpowiedź na tego typu pytania byłaby skazana na zarzut przekroczenia kompetencji, ale odpowiednio przygotowana analiza może dać organowi procesowemu podstawę do samodzielnego ustalenia, jakie były intencje obwinionego.
EN
A method of producing expert opinions on road traffic accidents evidenced by monitoring system recording, in which one of the participants is suspected of having deliberately orchestrated the collision is presented. The discussion was based on an actual event in which such a possibility was suggested by both the witnesses’ testimony as well as information on the participation of one of the drivers in a large number of similar events. Despite the fact that the questions the court expert was asked were formulated in an extremely general way, they were essentially aimed at establishing whether it was the intention of the defendant - the driver who had the right of way to provoke the collision in circumstances indicating the responsibility of the other participant. Obviously, a direct answer to this type of question was doomed to the complaint of exceeding the competences. However, an adequately formulated analysis may provide the judicial authority with a basis for an independent decision as to what the defendant’s intentions were.
EN
To characterize the deep structure of the Klippen Belt, we made magnetotelluric measurements in profiles across the western and eastern segments in the territory of Slovakia, from which we created 3D models. The models revealed significant differences in tectonic structure between these segments. In the western segment, the Klippen Belt is located in the southern reversing wing of the original subduction flower structure (retroarc thrusting) with an overthrust to the south onto the Inner Western Carpathian units. This structure was later modified by significant transpressional movements. In the eastern segment, the Klippen Belt is primarily an organic part of the accretionary wedge of the Outer Western Carpathians and it is overthrusted onto the Flysch Belt. This was followed by modification of the structures, mostly in a transpressional regime, including local reversing overthrusts and the development of a steep fault boundary, mainly along the southern margin, against the Inner Carpathian Paleogene succession. These differences between the structure of the western and eastern Klippen Belt segments indicate the contrast between the interaction of the western and eastern parts of the Inner Western Carpathians with the European Platform. In the western part, oblique collision and sinistral transpression dominate. In the eastern part, by contrast, subduction and orthogonal collision dominated over later transpressional modifications.
EN
This article presents a mathematical model of a planar system for the multipoint, oblique, and eccentric impact of rough bodies. The created model served for numerical investigations of the system’s behaviour. To analyse the influence of various parameters, three simplified cases were defined. Each of these cases focused on different aspects of the simulation. The first case was used to determine how many contacting bodies undergo impact at a given time point. This result was then compared with the experimental observations, which gave good agreement. The second case investigated the influence of the body configuration and the coefficient of friction (COF) on the sliding process during impact. Depending on the parameter values, the sliding process was divided into three main areas: slip-reversal slip, stick-slip, and continuous slip with increasing sliding velocity. The third case focused on the energy dissipation expressed by the coefficient of restitution (COR) and the angle of incidence of the initiating impact; this case showed possible improvement areas of the used impact force model.
PL
W artykule przedstawiono model matematyczny płaskiego zderzenia wielopunktowego. Konfiguracja zderzających się ciał pozwalała na wystąpienie zarówno zderzenia mimośrodowego jak i ukośnego oraz uwzględniała tarcie. Opracowany model posłużył następnie badaniom symulacyjnym. W celu przeanalizowania wpływu różnych parametrów na zachowanie systemu zdefiniowano trzy uproszczone przypadki. W pierwszym badano, jaka ilość ciał bierze jednocześnie udział w zderzeniu. Przeprowadzone porównanie otrzymanych wyników z obserwacjami eksperymentu pokazało dobrą zgodność. W drugim przypadku badano wpływ konfiguracji zderzających się ciał oraz współczynnika tarcia na przebieg procesu poślizgu w trakcie zderzenia. W zależności od wartości parametrów możliwe są trzy główne scenariusze: poślizg–zmiana kierunku poślizgu, poślizg–zatrzymanie poślizgu, ciągły poślizg ze wzrastającą prędkością poślizgu. Trzeci przypadek skupiał się na dyssypacji energii wyrażonej poprzez współczynnik restytucji oraz kierunku uderzenia inicjującego; przypadek ten pokazał obszary, w których wykorzystany model siły zderzenia wymaga dopracowania.
EN
The paper deals with issues connected with the behaviour of a streamer cable towed by a survey seismic vessel when the cable undergoes a strike triggered by collision with an underwater moving object. The consequences of such collisions may be both threat to the life of marine animals or damage to underwater units and large economic losses suffered by vessel owners. The risk of such collisions has increased over the last years as a result of increased offshore seismic survey operations. Therefore, a towed streamer should be very robust. To assure its robustness, we should know the deformation mechanism of a single streamer cable. This in turn requires the development of an appropriate mathematical model of such a phenomenon. In particular, the paper presents the characteristics of seismic survey vessels and streamers; an analysis of collisions that have occurred in the past; a statement of the problem, and a computer-aided system supporting simulation of the cable behaviour. To obtain all the necessary design parameters regarding the deformation mechanism of a streamer cable, we set up a dedicated computer-aided system that supports their calculation.
EN
The numerical approach for determination of influence of deformation of the gas bubble (radius 0.74 mm) on added mass coefficient in (i) steady-state conditions and (ii) during approach to the horizontal wall, is proposed. It is shown that the bubble deformation can be tuned numerically (within the range 1.06 - 1.88) via proper variations of the Laplace pressure, without changing the bubble radius. Influence of the bubble deformation on its motion parameters is discussed and compared to theoretical predictions regarding the bubble drag coefficient and Reynolds number. Moreover, the approach allowing determination of the added mass of rising bubble, on the basis of variations in fluid kinetic energy, is described. It is shown that calculated added mass variations strongly depends on the interplay between (i) the bubble deformation ratio and (ii) its rising velocity. This effect is especially important for added mass of a gas bubble approaching a solid wall, because it can affect the kinetics of drainage of the separating liquid film formed under dynamic conditions, when Re >> 1.
17
Content available remote Weryfikacja możliwości rozpoznania kolizji przy małych prędkościach uderzenia
PL
Artykuł zawiera analizę możliwości zweryfikowania odczucia przez kierowcę i pasażerów samochodu kolizji przy małych prędkościach uderzenia, wynoszących kilka lub kilkanaście kilometrów w na godzinę. Do takich kolizji dochodzi niejednokrotnie podczas manewrowania na placach parkingowych. Odczucie przez osoby wewnątrz samochodu uderzenia w inny pojazd bywa utrudnione z uwagi na jednoczesne hamowanie pojazdu. Szarpnięcie spowodowane zderzeniem bywa często zbyt słabe, aby osoba je zarejestrowała.
EN
An analysis is performed of the possibility of vehicle driver and occupants to recognize if they are involved in a collision at low impact speeds of a few or several km/h. Such collisions frequently happen during manoeuvres on parking lots. It is difficult for vehicle occupants to feel the impact against another vehicle because braking takes place simultaneously. The jolt caused by the collision is often too slight to be registered by a person.
EN
This study aims to identify and quantify the economic benefits of eliminating collisions between two transport systems: rail and inland waterway transport. The collision between transport systems is caused here by the obsolete structure of a railway drawbridge, which constitutes an element of the railway line used by freight and passenger transport and is located on the main inland waterway used by inland waterways freight transport. Railway transport results in limitations of inland waterway transport and, vice versa, inland waterways transport blocks railway transport during lifting of the bridge span. In the case of railway transport, the low capacity of the single-track railway bridge constitutes an additional limitation of the development of transportation. There are plans to eliminate the collision in the regional transport system by constructing a new railway bridge in place of the old drawbridge. The effects of the transportation infrastructure improvement were measured directly for both rail and inland water freight systems as well as the result of the interaction between passenger rail and car and bus transport. In order to compare the different types of impact, the effects of different actions were valued in monetary terms. The planned intervention, as investigated here, will lead to reductions in the cost of time of inland waterways freight transport and costs of time of rail passenger and freight transport and a decrease in the external costs of transport. This will make possible transportation services that are both cheaper and more reliable.
19
Content available remote Wzajemne zderzenia pieszych w ruchu drogowym. Zagadnienia sporne i dyskusyjne
PL
Artykuł omawia problematykę zderzeń ze sobą pieszych w ruchu lądowym, akcentując perspektywę prawnokarną. Biegacz, łyżworolkarz, wrotkarz, a nawet zwykły spacerowicz, poruszając się, może doprowadzić do zdarzenia, w którym ucierpi inna osoba, będąca uczestnikiem ruchu. Na kanwie analizy zasad bezpieczeństwa obowiązujących w takich sytuacjach, autor stara się zakreślić pole potencjalnej odpowiedzialności karnej. Rozważania te mają charakter zarówno dogmatyczny, jak i praktyczny, dzięki części poświęconej omówieniu zdarzeń hipotetycznych. W pracy autor posłużył się metodą badawczą w postaci wtórnej analizy dawnych zdarzeń (orzecznictwa oraz literatury prawniczej), jak i studium przypadków.
EN
The article is devoted to a discussion of collisions between pedestrians in road traffic with an emphasis on the aspects of criminal law. A runner, a rollerblade skater, a roller skater, or even an ordinary person taking a stroll may cause an event in which another participant of the road traffic will be affected. On the basis of the analysis of traffic safety rules, the author makes an attempt to define the scope of possible criminal liability. His approach is both dogma and practice orientated, manifested in the section devoted to the discussion of hypothetical events. The author employs the research method of secondary analysis of past events (the case law and legal literature) as well as case studies.
EN
Road accidents and collisions are very common in Poland and, although for the last several years their number has been constantly decreasing, it is still one of the highest in Europe. This article attempts to provide an answer to the question whether drivers’ overrating the changes in the Polish road transport infrastructure might contribute to the status quo – the factor that has so far been left uninvestigated. In [21] the authors demonstrate that drivers take notice of the changes and perceive them as changes for the better.
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