Wyniki wyszukiwania dla: COLLISION%20AVOIDANCE
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Decision Support Based on Optimal Collision Avoidance Path and Collision Risk
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Parameters of evolutionary algorithm in problem of collision avoidance at sea
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Genetic operators of evolutionary algorithm in problem of collision avoidance at sea
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Mean Crossover in evolutionary path planning method for maritime collision avoidance
PublikacjaAbstract: This paper presents the use of mean crossover genetic operator for path planning using evolutionary algorithm for collision avoidance on sea. Mean crossover ensures widening of the possible solutions' set that can be achieved in comparison to exchange crossover variant. The research shown, that the mean crossover allows to achieve results independent from the initial generation and quicker transition of thealgorithm from...
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Evolutionary Sets Of Safe Ship Trajectories: A New Approach To Collision Avoidance
PublikacjaThe paper introduces a new method of solving multi-ship encounter situations for both open waters and restricted water regions. The method, called evolutionary sets of safe trajectories combines some of the assumptions of game theory with evolutionary programming and aims to find optimal set of safe trajectories of all ships involved in an encounter situation. In a two-ship encounter situation it enables the operator of an on-board...
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Recognition Of Colours And Collision Avoidance In Robotics Using Optical Fiber Sensors
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A Target Information Display for Visualising Collision Avoidance Manoeuvres in Various Visibility Conditions
PublikacjaThe paper introduces a new approach to displaying information on targets. The proposed display visualises three types of information: targets’ motion parameters (typical for target tracking), combinations of own course and speed which collide with those targets (typical for Collision Threat Parameters Area display by Lenart (1983)) and combinations of own course and speed which are not compliant with COLREGS in this case (based...
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A new method of ship routing on raster grids, with turn penalties and collision avoidance
PublikacjaArtykuł przedstawia nowy algorytm znajdowania optymalnych tras na siatkach rastrowych. Szczegółowo opisano zastosowane struktury danych, dzięki którym algorytm ma liniową złożoność obliczeniową. Na podstawie algorytmu opracowano metodę wyznaczania tras dla statków, uwzględniającą kwestie unikania kolizji z innymi statkami i przeszkodami nawigacyjnymi.Przedstawiono dwa warianty metody, dedykowane odpowiednio systemom pokładowym...
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Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations
PublikacjaShip domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...
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Path planning algorithm for ship collisions avoidance in environment with changing strategy of dynamic obstacles
PublikacjaIn this paper a path planning algorithm for the ship collision avoidance is presented. Tested algorithm is used to determine close to optimal ship paths taking into account changing strategy of dynamic obstacles. For this purpose a path planning problem is defined. A specific structure of the individual path and fitness function is presented. Principle of operation of evolutionary algorithm and based on it dedicated application...
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Towards a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Toward a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Ship Collision Risk Assessment Based on Collision Detection Algorithm
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Collision-Free Network Exploration
PublikacjaA set of mobile agents is placed at different nodes of a n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round may two agents occupy the same node. In each round, an agent may choose to stay at its currently occupied node or to move to one of its neighbors. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest possible...
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Collision-free network exploration
PublikacjaMobile agents start at different nodes of an n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round two agents may occupy the same node. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest time required to reach a configuration in which each agent has visited all nodes and returned to its starting location. In...
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A ship domain-based model of collision risk for near-miss detection and Collision Alert Systems
PublikacjaThe paper presents a new model of ship collision risk, which utilises a ship domain concept and the related domain-based collision risk parameters. An encounter is here described by five variables representing: degree of domain violation (DDV), relative speed of the two vessels, combination of the vessels’ courses, arena violations and encounter complexity. As for the first three variables, their values can be directly computed...
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Financial risk information avoidance
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Tomasz Wąsowicz dr hab.
OsobyAbsolwent Technikum Elektrycznego w Słupsku (1997 rok) oraz Wydziału Matematyki, Fizyki i Informatyki Uniwersytetu Gdańskiego (2002 rok). W 2006 roku obronił dysertację doktorską z fizyki na WMFiI UG. Pracując już w PG, w 2018 roku uzyskał habilitację. W pierwszym okresie prace badawcze Tomasza Wąsowicza miały związek ze spektroskopią atomową wysokiej zdolności rozdzielczej i koncentrowały się na pomiarze i analizie prawdopodobieństw...
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Comments to the article by Ramos et al. ‘Collision avoidance on maritime autonomous surface ships: Operators’ tasks and human failure events’ (Safety Science Vol. 116, July 2019, pp. 33–44)
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An adaptive approach to the problem of collision avoiding at sea
PublikacjaW referacie przedstawiono koncepcję podejścia adaptacyjnego do unikania kolizji na morzu. Omawiany problem został sklasyfikowany jako problem uczenia się ze wzmocnieniem. Zamieszczono opis podstawowych technik uczenia się ze wzmocnieniem, ich ograniczeń i sposobu w jaki można zapewnić efektywne uczenie się, mimo wspomnianych ograniczeń. Zaprezentowana metoda została zilustrowana przykładowym procesem konstrukcji modelu i algorytmami...
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Electron collision with sulfuryl chloride (SO2Cl2) molecule
PublikacjaStosując liniową metodę transmisyjną zmierzono całkowite przekroje czynne (TCS) na zderzenie elektronów z drobinami SO2Cl2 w zakresie energii 0.5-150 eV. Stwierdzono obecność głębokiego minimum przy ok. 1.8 eV i szerokiego maksimum w pobliżu 9.5 eV. Przeprowadzono porównanie z dostępnymi wynikami dla innych związków zawierających grupę sulfonową.
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Electron collision with B(CD3)3 molecules
PublikacjaArtykuł prezentuje całkowite przekroje czynne na rozpraszanie elektronów na drobinach B(CD3)3 zmierzone dla niskich i średnich energii zderzenia. Wyniki porównano z elastycznymi i jonizacyjnymi przekrojami czynnymi obliczonymi dla drobiny B(CD3)3 dla średnich energii zderzenia. Porównano i przedyskutowano przekroje czynne dla drobin zawierających bor.
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Collision Risk-Informed Weather Routing for Sailboats
PublikacjaSelected COLREG rules, good seamanship and sheer common sense indicate that it is in a sailboat's interest to follow collision-free routes without relying on large power-driven ships to give way. Until now, however, no method has integrated a sailboat's weather routing with collision risk monitoring and collision avoidance. Therefore, a new deterministic approach to combine the above features within one method is introduced here....
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Probability modelling of vessel collisions
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Fuzzy Collision Threat Parameters Area (FCTPA) - a new display proposal
PublikacjaW rozdziale przedstawiono nową metodę wizualizacji umożliwiającą nawigatorom oszacowanie sytuacji zbliżenia dwóch statków i w razie konieczności - wybór manewru antykolizyjnego. Metoda ta jest oparta na metodzie CTPA i oferuje następujące, nowe w stosunku do CTPA elementy: rozmyte sektory zabronionych prędkości i kursów oraz możliwość zastosowania dowolnej domeny statku. Metoda jest wystarczająco szybka do zastosowania w dowolnym...
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A Framework of a Ship Domain-based Collision Alert System
PublikacjaThe paper presents a framework of a planned ship collision alert system. The envisaged system is compliant with IMO Resolution MSC.252 (83) “Adoption of the revised performance standards for Integrated Navigation Systems (INS)”. It is based on a ship domain-oriented approach to collision risk and introduces a policy of alerts on dangerous situations. The alerts will include cautions, warnings and alarms, which will be triggered...
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Cross sections for electron collision with pyridine [C5H5N] molecule
PublikacjaThe absolute grand -total cross section (TCS) for electron scattering from pyridine, C5H5N, molecules has been measured at impact energies from 0.6 to 300 eV in the linear electron-transmission experiment. The obtained TCS energy dependence appears to be typical for targets of high electric-dipole moment; the cross section generally decreases with rising energy, except for the 3–20 eV range, where a broad enhancement peaked near...
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The concept of anti-collision system of autonomous surface vehicle
PublikacjaThe use of unmanned vehicles in various fields of science and the economy is becoming more common. An extremely important aspect of creating this type of solution is to provide autonomous vehicle navigation, which does not require interference of the human factor or in which it is limited to a minimum. This article discusses the concept of autonomous anti-collision system of unmanned surface vehicle. It proposed a sensor system...
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An analysis of domain-based ship collision risk parameters
PublikacjaAccording to a lot of contemporary research on ship collision avoidance the classic approach parameters – distance at closest point of approach (DCPA) and time to the closest point of approach (TCPA) – are not sufficient for estimating ship collision risk and for planning evasive manoeuvres. Consequently new measures are introduced, often utilizing the concept of a ship domain. Their drawback, up to this point, was the lack of...
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System of Safe Ship Steering In a Collision Situation at Sea.
PublikacjaPrzedstawiony hybrydowy system sterowania statkiem w sytuacji kolizyjnej na morzu, ma umożliwić nawigatorowi podjęcie decyzji pozwalającej na bezpieczne przejście przez dany akwen z uwzględnieniem warunków pogodowych, i spotkanych ograniczeń nawigacyjnych o charakterze statycznym i dynamicznym. System ten łączy pracę dwóch technik komputerowych, algorytmów ewolucyjnych do wyznaczania optymalnej ścieżki przejścia i sterowania rozmytego...
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Predicting Risk of Collision for Oil Tankers in the Gulf of Finland
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Supporting Navigator's Decisions By Visualizing Ship Collision Risk
PublikacjaW artykule wprowadzono metodę wizualizacji, która umożliwia nawigatorowi oszacowanie ryzyka kolizji i (w razie konieczności) wybór manewru antykolizyjnego. Metoda jest oparta na wcześniejszej metodzie CTPA, uwzględnia dowolną zadaną domenę statku i jest wystarczająco szybka do zastosowania w okrętowych systemach wspierania decyzji nawigatora.
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A Simple Neural Network for Collision Detection of Collaborative Robots
PublikacjaDue to the epidemic threat, more and more companies decide to automate their production lines. Given the lack of adequate security or space, in most cases, such companies cannot use classic production robots. The solution to this problem is the use of collaborative robots (cobots). However, the required equipment (force sensors) or alternative methods of detecting a threat to humans are usually quite expensive. The article presents...
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Collision Strengths of Astrophysical Interest for Multiply Charged Ions
PublikacjaThe electron impact excitation and ionization processes are crucial for modeling the spectra of different astrophysical objects, from atmospheres of late-type stars to remnants of supernovae and up to the light emission from neutron star mergers, to name just a few. Despite their signifi- cance, however, little is known quantitatively about these processes for low- and medium-impact energies of, say, Ekin . 5000 eV of the free...
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Electron Elastic Collisions with C3F6 Molecule
PublikacjaObliczono różniczkowy i scałkowany przekrój czynny na zderzenia elektronu z molekułą C3F6 w zakresie średnich i wysokich energii (50-1000eV). Obliczenia wykonano stosując metodę atomów niezależnych. Stwierdzono dobrą zgodność z wynikami oszacowanymi na podstawie eksperymentu.
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Electron collisions with ethylene oxide molecules
PublikacjaZmierzono całkowite przekroje czynne na rozproszenie elektronów na drobinach tlenku etylenu w zakresie energii od 0.7 do 400 eV. Obliczono przekroje czynne na zderzenia sprężyste oraz przekroje czynne na jonizację. Otrzymane wyniki obliczeń są zgodne z wynikami eksperymentalnymi w pokrywającym się przedziale energii zderzenia. Wyniki uzyskane dla tlenku etylenu porównano z przekrojami czynnymi dla jego izoelektronowego odpowiednika...
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Hybrid system of safe ship steering in a collision situation at sea
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Fluorescence emission of carbon disulfide in low energy electron collision.
PublikacjaZbadano widma emisyjne dwusiarczku węgla w zakresie widmowym od 235 nm do575 nm wzbudzane zderzeniami elektronów o energii 9.7eV I 15eV. W otrzymanych widmach największe natężenie miały pasma pochodzące z dysocjacji cząsteczek dwusiarczku węgla.
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Absolute total cross-section measurements for electron collision with tetrahydrofuran
PublikacjaZmierzono absolutny, całkowity przekrój czynny na rozpraszanie elektronów na drobinach tetrahydrofuranu (C4H8O) w zakresie energii zderzenia 1-370 eV. Otrzymane wyniki pozostają w dobrej zgodności z sumą obliczonych przekrojów elestycznych i jonizacyjnych. Przeprowadzono porównananie z innymi dostępnymi przekrojami czynnymi.
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Cross sections for electron collision with five-membered ring heterocycles
PublikacjaCałkowity absolutny przekrój czynny (TCS) na rozpraszanie elektronów na cząsteczce izoksazolu (CH)3NO, został zmierzony przy wykorzystaniu liniowej techniki transmisyjnej dla energii zderzenia od 1 do 400 eV. Zależność energetyczna funkcji TCS jest typowa dla cząsteczek silnie polarnych; w całym zakresie badanych energii wartość TCS maleje wraz ze wzrostem energii zderzenia. Zaobserwowano wąskie struktury rezonansowe w okolicy...
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Assessment of a critical area for a give-way ship in a collision encounter
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Tools for an Extended Risk Assessment for Ropax Ship-Ship Collision
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A risk-informed ship collision alert system: Framework and application
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Temporal pattern of wildlife-train collisions in Poland
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Electron collisions with trifluorides: BF3 and PF3 molecules.
PublikacjaArtykuł prezentuje zmierzone metodą transmisyjną całkowite przekroje czynne na rozpraszanie elektronów na płaskich drobinach BF3 i piramidalnych cząstkach PF3 w zakresie energii 0.5-370eV. Otrzymane wyniki zostały porównane z dostępnymi cząstkowymi przekrojami czynnymi (tj. sprężystym, jonizacyjnym). Zaprezentowane całkowite przekroje czynne porównano także ze sobą aby zbadać wpływ geometrii drobiny na wartość i kształt całkowitego...
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Electron collisions with nitrogen trifluoride (NF3) molecules.
PublikacjaArtykuł prezentuje zmierzone całkowite przekroje czynne oraz obliczone sprężyste i jonizacyjne przekroje czynne na rozpraszanie elektronów na drobinach fluorku azotu (NF3) dla niskich i średnich energii zderzenia. Wyniki porównano z dostępnymi cząstkowymi przekrojami czynnymi. W celu zbadania wpływu podstawienia atomów fluoru w miejsce atomów wodoru porównano całkowite przekroje czynne dla NF3 i NH3 (efekt fluorowania).
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Electron collisions with boron trichloride (BCl3) molecules
PublikacjaPrzedstawiono wyniki pomiarów absolutnych, całkowitych przekrojów czynnych na rozpraszanie elektronów na drobinach BCl3. Pomiary przeprowadzono w zakresie energii 0.3 - 370eV. Otrzymane wyniki porównano z dostępnymi cząstkowymi przekrojami czynnymi (tj. sprężystym, jonizacyjnym. Przedyskutowano rolę peryferyjnych atomów molekuły, zestawiając wyniki pomiarów całkowitych przekrojów czynnych dla drobin BCl3 i BF3.
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Ionization and fragmentation of furan molecules by electron collisions
PublikacjaCation mass spectra obtained by electron impact were measured to investigate the ionization and ionic fragmentation of furan, C4H4O, molecules in the gas phase. The most abundant cations, with comparable intensities in the mass spectra, were the parent, C4H4O+, cation (68 amu) and the C3H3+ fragment (39 amu). The appearance energies of most of the observed ionic fragments were determined and the possible fragmentation processes...
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A method of determining and visualizing safe motion parameters of a ship navigating in restricted waters
PublikacjaThe paper presents a method of displaying ship collision avoidance information which is based on an unconventional Collision Threat Parameters Area (CTPA) technique. The solution presented here extends CTPA's functionality from past works by supporting navigation in restricted waters and handling ship domains analytically instead of numerically. It visualizes potential navigational threats as well as possible collision avoidance...
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Pedestrian and bicycle bridges as examples of safe collision-free road crossings
PublikacjaPedestrians are most at risk when they are crossing the road. This represents a significant proportion of all fatalities among pedestrians, amounting respectively to 50% in non-built-up areas and 75% in built-up areas. The most frequent reason for this accident is failure to give way. What is most terrible is that 30% of pedestrian accidents occurred at marked pedestrian crossings. Therefore, an important part of pedestrian safety...
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Search safe ship trajectories in collision situation at sea by evolutionary computation
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Simulation of damage process of containership's side structure due to collision with a rock
PublikacjaW artykule przedstawiono wyniki uproszczonego modelowania numerycznego procesu kolizji burty kontenerowca ze skałą. Analiza wyników modelowania pozwala wyciągnąć wnioski o charakterze zjawiska jak również określić obszar i głębokość uszkodzenia wywołanego przez penetrującą skałę w celu doboru wymiarów geometrii i wypełniacza dla drugiej bariery ochronnej.
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A unified measure of collision risk derived from the concept of a ship domain
PublikacjaW artykule zaprezentowano nową miarę ryzyka kolizji dwóch statków, wywiedzioną z koncepcji domeny statku. Jej prostota oraz fakt, że uwzględnia ona kursy obydwu statków czynią ją dobrą alternatywą dla często stosowanego pojęcia odległości największego zbliżenia. Miara ta jest elastyczna, tzn. można korzystać z niej w powiązaniu z dowolną, zadaną domeną statku. Szczegółowo przedstawiono wyprowadzenia wszystkich niezbędnych wzorów...
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Coalition Shaping the Vaccination Landscape
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Determining and visualizing safe motion parameters of a ship navigating in severe weather conditions
PublikacjaThe paper presents a method of determining, organizing and displaying ship collision avoidance information, which is based on the Collision Threat Parameters Area (CTPA) technique. The method makes it possible to visualize navigational threats as well as possible collision avoidance manoeuvres. The solution is focused on supporting navigation in severe weather conditions. Normally collision avoidance decisions are made taking into...
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Electron collisions with tetrafluoroethylene (C2F4) and ethylene (C2H4) molecules.
PublikacjaStosując liniową metodę transmisyjną zmierzono całkowite przekroje czynne(TCS) na zderzenie elektronów z drobinami C2F4 w zakresie energii 0.6-370eV.Stwierdzono obecność szerokiego maksimum przy ok. 30eV. Dla porównania zmierzono TCS dla C2H4. Przedyskutowano wpływ podstawienia atomu fluoru w miejsce wodoru.
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Electronic states of tetrahydrofuran molecules studied by electron collisions
PublikacjaElectronic states of tetrahydrofuran molecules were studied in the excitation energy range 5.5-10 eV using the technique of electron energy loss spectroscopy in the gas phase. Excitation from the two conformations, C2 and Cs, of the ground state of the molecule are observed in the measured energy loss spectra. The vertical excitation energies of the 3(no3s) triplet state from the C2 and Cs conformations of the ground state of the...
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Collisions of electrons with trimethylamine N(CH3)3 molecules
PublikacjaPrzedstawiono całkowite przekroje czynne na rozpraszanie elektronów na drobinach N(CH3)3, zmierzone dla niskich i średnich energii zderzenia. Wyniki porównano z elastycznymi i jonizacyjnymi przekrojami czynnymi, obliczonymi dla tej drobiny, dla średnich energii zderzenia. Porównano i przedyskutowano przekroje czynne dla drobin zawierających azot jako atom centralny.
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Multiple-scattering and electron-uracil collisions at low energies
PublikacjaDyskutowany jest związek dwóch znanych metod w teorii rozpraszania elektronów na cząsteczkach : potencjałów zerowego promieniu i metody potencjałów "muffin-tin". Rozwój obu metod pozwala na stworzenie nowej techniki obliczenia parcjalnych faz i przekrojów czynnych w nazwanej teorii. Technika ta ma zastosowanie do zagadnienia dotyczącego układu elektron-uracil.
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Collisions of electrons with trimethylphosphine [P(CH3)3] molecules
PublikacjaPrzedstawiono wyniki pomiarów całkowitych przekrojów czynnych na rozpraszanie elektronów na molekułach P(CH3)3. Pomiary przeprowadzono w przedziale energii od 0,4 do 400eV. Obliczono przekroje czynne na rozpraszanie sprężyste i na jonizację. Wyniki porównano z przekrojami czynnymi dla innych związków zawierających fosfor jako atom centralny oraz grupę metylową.
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Ionization and ionic fragmentation of tetrahydrofuran molecules by electron collisions
PublikacjaElectron impact ionization and ionic fragmentation of tetrahydrofuran molecules in the gas phase were studied in the energy range from ionization threshold up to 150 eV using the technique of mass spectrometry. The cation mass spectra, ionization and ionic fragmentation efficiencies were measured over this energy range. Well-resolved mass peaks were detected in the mass range 10-72 amu and assigned to corresponding ionic molecular...
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Understanding the formation of metastable furan dication in collisions with ions
PublikacjaThis work relies on complementary theoretical and experimental studies of the processes induced by ion-furan collisions. Results of the Molecular Dynamics simulations and exploration of the energy profiles combined with coincidence mass spectrometry provide complete picture of the fragmentation of furan dication.
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Heuristic Method of Safe Manoeuvre Selection Based on Collision Threat Parameters Areas
PublikacjaThis paper is a continuation of papers dedicated to a radar-based CTPA (Collision Threat Parameters Area) display designed to support safe manoeuvre selection. The display visualizes all the ships in an encounter and presents situational overview from the own ship’s point of view. It calculates and displays information on unsafe or unrealistic own ship’s course & speed allowing a user to select a safe manoeuvre. So far only the...
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Trajectory planning in collision situations at sea by evolutionary computation - experiments with moving targets
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Numerical analysis of lumbar spine injury during road safety barrier collision
PublikacjaPurpose: Enhancing road safety is a critical goal worldwide, necessitating the development of clear standards for road safety systems. This study focuses on lumbar spine (L-spine) compression injuries during collisions with concrete road safety barriers (RSBs). It aims to analyze internal forces during impact to understand L-spine injury biomechanics in such accidents. Methods: The research included a literature review, analyzing...
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State selective electron capture in the collision of S3+ ions in atomic hydrogen and helium.
PublikacjaZostało zaprezentowane teoretyczne podejście, uwzględniające obliczenia krytycznych adiabatycznych energii potencjalnych i dynamicznych sprzężeń pomiędzy nimi, do opisu procesu przechwytu elektronu przez jony siarki w zderzeniach z atomami wodoru i helu.
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Total cross-section measurements for electron collision with α-tetrahydrofurfuryl alcohol (C5H10O2)
PublikacjaPrzedstawiono całkowite przekroje czynne (TCS) na rozpraszanie elektronów na drobinach α-tetrahydrofurfurylu, zmierzone w zakresie energii zderzenia 1-370 eV oraz policzone powyżej 50 eV. Przedyskutowano otrzymaną zależność TCS od energii. Wyniki porównano z dostępnymi teoretycznymi i eksperymentalnymi przekrojami czynnymi.
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Collision-induced luminescence spectra of pyridine bombarded by 1000 eV He+ cations
PublikacjaHere we show collision-induced luminescence spectra measured for collisions of the He+cations with thearomatic six-membered ring of the pyridine molecule (C5H5N). Distinct emission bands due to the CH(A2Δ→X2Πr;B2Σ+→X2Πr;C2Σ+→X2Πr), CN(B2Σ+→X2Σ+), C2(d3Πg→a3Πu), and NH(A3Π→X3Σ−) transitions, aswell as atomic H, He, and C lines have been observed. Apart from the He atoms, all the emitters arise from thefragmentation of the pyridine...
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Biomechanics of Lumbar Spine Injury in Road Barrier Collision–Finite Element Study
PublikacjaLiterature and field data from CIREN database have shown that lumbar spine injuries occur during car crashes. There are multiple hypotheses regarding how they occur; however, there is no biomechanical explanation for these injuries during collisions with road safety barriers (RSBs). Therefore, the objective of this study was to investigate the mechanics of vertebral fractures during car collisions with concrete RSBs. The finite...
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Autonomous Control of the Underwater Remotely Operated Vehicle in Collision Situation with Stationary Obstacle
PublikacjaThe article considers the problem of autonomous control of the underwater remotely operated vehicle mini Remotely Operated Vehicle (ROV) in a collision situation with a stationary obstacle. The control of the collision avoidance process is presented as a synthesis of fuzzy proportional-differential controllers for the control of distance and orientation concerning the detected stationary obstacle. The control of the submergence...
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Charge transfer and formation of complexes in the He+ collisions with the furan molecules
PublikacjaCharge transfer and formation of the collision complexes have been studied experimentally in fragmentation of the furan molecules in collisions with He+ cations. The excited atomic and diatomic fragments of furan have been identified using collision-induced luminescence spectroscopy. Charge transfer ionization of the furan molecules has been observed in production of helium atoms in the excited 1s4d 1D2, 3D1,2,3 states. The fragmentation...
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Determination of energy-transfer distributions in ionizing ion-molecule collisions
PublikacjaThe main objective of this study is to determine the energy transfer occuring in ion-molecule collisions. In order to solve this problem, we followed two approaches; the first one by validating a purely experimental method and the second one by testing a new theoretical model M3C (Microcanonical Metropolis Monte Carlo).
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Investigation of rotational state-changing collisions of C2N− ions with helium
PublikacjaThe cross sections for rotational inelastic collisions between atoms and a molecular anion can be very large, if the anion has a dipole moment. This makes molecular anions very efficient in cooling atomic gases. We address rotational inelastic collisions of Helium atoms with the molecular anion C2N–. Here we present preliminary calculations of the potential energy surface.
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Experimental research on evolutionary path planning algorithm with fitness function scaling for collision scenarios
PublikacjaThis article presents typical ship collision scenarios, simulated using the evolutionary path planning system and analyses the impact of the fitness function scaling on the quality of the solution. The function scaling decreases the selective pressure, which facilitates leaving the local optimum in the calculation process and further exploration of the solution space. The performed investigations have proved that the use of scaling...
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Determination of collision criteria and causation factors appropriate to a model for estimating the probability of maritime accidents
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DETERMINATION OF ADDITIONAL TENSION IN TOWED STREAMER CABLE TRIGGERED BY COLLISION WITH UNDERWATER MOVING OBJECT
PublikacjaThe 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...
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Non-ergodic fragmentation upon collision-induced activation of cysteine–water cluster cations
PublikacjaCysteine–water cluster cations Cys(H2O)3,6 + and Cys(H2O)3,6H+ are assembled in He droplets and probed by tandem mass spectrometry with collision-induced activation. Benchmark experimental data for this biologically important system are complemented with theory to elucidate the details of the collisioninduced activation process. Experimental energy thresholds for successive release of water are compared to water dissociation energies...
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Theoretical treatment of charge-transfer processes induced by collision of C^q+ ions with uracil
PublikacjaWychwyt ładunku został opisany teoretycznie przy użyciu podstawowych metod chemii kwantowej, uzupełnionych półklasycznym opisem dynamiki zachodzącego procesu. Otrzymane przekroje czynne pokazują zróżnicowane zachowanie pod wpływem struktury elektronowej badanego jonu i mogą służyć do wyjaśniania prowadzonych badań doświadczalnych.
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Identification of Risk Factors for Collisions Involving Cyclists Based on Gdansk Example
PublikacjaThe role of pedestrian and bicycle traffic in Poland has growing trend. The comprehensive traffic study, conducted in Gdansk in 2016, has confirmed the increase in the number of cyclists and their share in the modal split. Therefore, it is particularly important to ensure the safety of this group of unprotected road users. Only in 2015 on the roads of Gdansk occurred 93 accidents (excluding collisions) involving cyclists. As a...
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Low-energy positron collisions with water: elastic and rotationally inelastic scattering
PublikacjaDifferential, integral and momentum transfer cross sections for the vibrationally elastic and rotationally inelastic scattering of positrons from water at low collision energy (E ≤ 10 eV) are reported. Several models within the R-matrix method are used to compute the body-fixed T-matrices, while the scattering calculations are performed within the fixed-nuclei approximation corrected with the standard Born-closure formula. These...
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Charge dependence of fragmentation process induced by ion collisions with furan molecule
PublikacjaThe goal of this work is to describe the system evolution after ion-molecule interaction. We combine different quantum chemistry and statistical mechanics approaches in order to give extended description of the process. Herein we report on a recent study of the fragmentation mechanism of neutral, singly- and doubly-ionized furan molecule in the gas phase.
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PROBLEMS OF COLLISIONS BETWEEN ADJACENT STEEL STRUCTURES UNDER EARTHQUAKE EXCITATION
PublikacjaNowadays, the high level of urbanization forces the engineers to design closely-separated structures and to take into account many factors influencing their response, including collisions between them due to insufficient separation distance during moderate to strong ground motions. Recent observations as well as experimental and numerical investigations have confirmed that interactions...
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Collusion and bid rigging in the construction industry: case studies from Poland
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Problems of collisions between adjacent steel structures under earthquake excitation
PublikacjaNowadays, the high level of urbanization forces the designers to design closely-separated structures and to take into account many factors influencing the response of these structures, which may collide due to insufficient separation distance during moderate to strong ground motions. Recent observations as well as numerical and experimental investigations have confirmed that the interactions between structures may lead to significant...
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Cross sections for ionization and ionic fragmentation of pyrimidine molecules by electron collisions
PublikacjaThe electron impact mass spectroscopy and the total ion collection measurements were used to investigate the ionization and ionic fragmentation of the pyrimidine, C4H4N2, molecules in the gasphase. The cation mass spectra were measured in the 10−85 amu range and the observed mass peaks assigned to corresponding ionic fragments. The most abundant cation in the mass spectra is the parent cation, C4H4N+2, at 80 amu. The appearance...
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Optical Spectroscopic Studies of Tetrahydrofuran Fragmentation Induced by Collisions with Dihydrogen Cations
PublikacjaCollisions of dihydrogen cations with tetrahydrofuran molecules have been studied. Luminescence spectra and the emission functions of the excited products at projectile energies ranging from 8 to 1000 eV have been measured using collision-induced emission spectroscopy. The recorded spectra are dominated by the atomic lines of the hydrogen Balmer series, whose intensities decrease more quickly than derived by the quantum-theoretical...
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Electron collisions with cyanoacetylene HC3N : Vibrational excitation and dissociative electron attachment
PublikacjaWe experimentally probe electron collisions with HC3N in the energy range from 0 to 10 eV with the focus on vibrational excitation and dissociative electron attachment. The vibrational excitation cross sections show a number of resonances which are mode specific: the two dominant π∗ resonances are visible in the excitation of all the vibrational modes; however, broad σ ∗ resonances are visible only in certain bond-stretching vibrational...
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A non-adiabatic wavepacket dynamical study of the low energy chargetransfer process in the S3+ + H collision
PublikacjaThe collisional system S3+ + H?S2+ + H+ has been studied using a time-dependent wavepacket methodologyin two-dimensions. Using available potential energy surfaces and coupling matrix elementsobtained from multireference ab initio calculations, five non-adiabatically coupled electronic states of1P symmetry have been included in the dynamical simulations. The collision has been studied in thelow energy regime of 1-10 eV. The wavepacket...
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A probabilistic model for accidental cargo oil outflow from product tankers in a ship–ship collision
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Collision‐Aware Routing Using Multi‐Objective Seagull Optimization Algorithm for WSN‐Based IoT
PublikacjaIn recent trends, wireless sensor networks (WSNs) have become popular because of their cost, simple structure, reliability, and developments in the communication field. The Internet of Things (IoT) refers to the interconnection of everyday objects and sharing of information through the Internet. Congestion in networks leads to transmission delays and packet loss and causes wastage of time and energy on recovery. The routing protocols...
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Weather Hazard Avoidance in Modeling Safety of Motor-Driven Ship for Multicriteria Weather Routing
PublikacjaWeather routing methods find the most suitable ocean?s route for a vessel, taking into account changeable weather conditions and navigational constraints. In the multicriteria approach based on the evolutionary SPEA algorithm one is able to consider a few constrained criteria simultaneously. The approach applied for a ship with hybrid propulsions has already been presented by one of the authors on previous TransNav?2009. This time...
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Conformation analysis and semiclassical dynamics study of charge exchange process induced by collision of C2+ ions with tetrahydrofuran
PublikacjaWe present the results of recent investigations of charge transfer processes in the collisions of C²⁺ ions with heterocyclic molecules of tetrahydrofuran.
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Hydroacoustic System in a Biomimetic Underwater Vehicle to Avoid Collision with Vessels with Low-Speed Propellers in a Controlled Environment
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The POCOBIO Database for Computed Scattering Cross-Sections for Positron Collisions with Biomolecular Systems
PublikacjaThe design of a database for positron interactions with biomolecular systems is outlined. The database contains only scattering cross sections, which are derived from theory. The data model is defined in a very flexible way, which facilitates the usage of weakly bound clusters of molecules and molecular systems with many tautomeric forms.
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EXPERIMENTAL AND NUMERICAL STUDY ON COLLISIONS BETWEEN STEEL STRUCTURES UNDER EARTHQUAKE EXCITATION
PublikacjaIn the time of high urbanization, the need to build closely-spaced structures forces the designers to take into account earthquake-induced collisions between adjacent buildings and their effects on the response of structures. Past and recent investigations confirmed that interactions between adjacent buildings during earthquakes may cause serious damages to the structural elements and may even lead to total collapse of the structure....
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Positron-electron correlation-polarization potentials for the calculation of positron collisions with atoms and molecules
PublikacjaWe present correlation-polarization potentials for the calculation of scattering cross sections of positrons with atoms and molecules. The potentials are constructed from a short-range correlation term and a long-range polarization term. For the short-range correlation term we present four different potentials that are derived from multi-component density functionals. For the long-range polarization term we employ a multi-term...
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A method for detecting possible near miss ship collisions from AIS data
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Uncertainty in maritime risk analysis: Extended case study on chemical tanker collisions
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Electron collisions with X(CH3)4 molecules (X = C, Si, Ge)
PublikacjaAbsolute grand-total cross sections (TCSs) for electron scattering from tetramethylmethane [C(CH3)4], tetramethylsilane [Si(CH3)4], and tetramethylgermane [Ge(CH3)4] molecules have been measured at electron-impact energies extending from around 0.5 to 300 eV in the linear electron-transmission experiment. The measured TCS energy dependences show very pronounced broad enhancement, peaking near 5.5 eV for Si(CH3)4 and Ge(CH3)4 molecules...
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublikacjaThis paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra...