Wyniki wyszukiwania - BazTech

1

Evaluating the safety performance of roundabouts

Alshannaq Mo'ath, Imam Rana

Transport Problems

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2020

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T. 15, z. 1

141--152

EN

The use of roundabouts is well recognized for sustaining an efficient and safe intersection. However, the safety results may vary based on the prevailing conditions. Therefore, this study assesses the safety performance of roundabouts in Jordan. This study developed a predictive model by collecting and analyzing all accident records of 12 major urban roundabouts in the country over 3 years. For developing the model, this study employed an accident frequency analysis. The model calculated the rate of accidents and incorporated the geometric and operational characteristics of roundabouts. This was followed by ranking the safety performance of the roundabouts. It was concluded that driver behavior of violating the traffic rules, lack of clear lane markings in the circulating area and inadequate signage at the roundabouts entries are the main causes of roundabout accidents. The research recommends including the developed predictive model in future traffic control and planning studies, for identifying hazardous locations, or for prioritizing roundabout improvements based on safety performance.

2

Problem selekcji wariantów programu informatyzacji uczelni publicznej

Zajkowski A., Zawiła-Niedźwiecki T.

Zeszyty Naukowe. Studia Informatica / Uniwersytet Szczeciński

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2015

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Nr 38

253--265

PL

Referat jest komunikatem z etapu badań literaturowych służących identyfikacji potencjalnych metod oceny i selekcji wariantów informatyzacji uczelni publicznej w ramach dysertacji podejmującej kwestię strategicznego kształtowania programu informatyzacji uczelni publicznej. Informatyzacja jest programowana wokół koncepcji architektury korporacyjnej. Na poszczególnych etapach programowania informatyzacji powstaje kwestia oceny i wyboru najlepszego wariantu. Rozważane jest korzystanie z metody analitycznego procesu hierarchicznego (AHP). Analizowane są zalety i wady takiego podejścia.

EN

The paper is a report of research within the dissertation taking the issue of strategic development of the program of computerization of public universities. Computerization is programmed around the concept of enterprise architecture. At various stages of computerization program, the question arises evaluation and selection of the best variant. Considered is the use of analytical hierarchy process method (AHP) and his mutation - ANP method. Analyzed are the advantages and disadvantages of such an approach.

3

Operational model for vessel traffic using optimal control and calibration

Shu Y., Daamen W., Ligteringen H., Hoogendoorn S.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2015

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nr 42 (114)

70--77

EN

Due to the ever-increasing economic globalization, the scale of transportation through ports and waterways has increased sharply. As the capacity of maritime infrastructure in ports and inland waterways is limited, it is important to simulate vessel behavior to balance safety and capacity in restricted waterways. Currently many existing vessel simulation models focus mainly on vessel dynamics and maritime traffic in the open ocean. These models are, however, inapplicable to simulating vessel behavior in ports and inland waterways, because behavior in such areas can be influenced by many factors, such as waterway geometry, external conditions and human factors. To better simulate vessel behavior in ports and waterways, we developed a new maritime traffic model by adapting the theory of pedestrian models. This new model comprises two parts: the Route Choice Model and the Operational Model. The Route Choice Model has been demonstrated and calibrated in our recent study, in which the desired speed is generated. This paper presents the second part of the model, the Operational Model, which describes vessel behavior based on optimal control by using the output of the Route Choice Model. The calibration of the Operational Model is carried out as well. In the Operational Model, the main behavioral assumption is that all actions of the bridge team, such as accelerating and turning, are executed to force the vessel to sail with the desired speed and course. In the proposed theory, deviating from the desired speed and course, accelerating, decelerating and turning will provide disutility (cost) to the vessel. By predicting and minimizing this disutility, longitudinal acceleration and angular acceleration can be optimized. This way, the Operational Model can be used to predict the vessel speed and course. Automatic Identification System (AIS) data of unhindered vessel behavior in the Port of Rotterdam, the Netherlands, were used to calibrate the Operational Model. The calibration results produced plausible parameter values that minimized the objective function. The paths generated with these optimal parameters corresponded reasonably well to the actual paths.

4

A discrete approach to assess the risks to the ship routes

Smolarek L., Guze S.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2010

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nr 20 (92)

128-133

EN

In the paper the hazard estimation model of assessment of risk on ship routes in terms of supporting the decision depending on the traffic stream parameters has been proposed. It has been obtained by applying of semi-Markov model of safety and partial models based on consecutive "k out of n: G" systems. Furthermore, the considerations on the aspects of the selection methodology for assessment of risk to a ship route have been presented.

PL

W pracy przedstawiono model określania ryzyka tras morskich w kategoriach wspomagania decyzji w zależności od parametrów natężenia ruchu. Zostało to uzyskane przez zastosowanie semi-Markowskiego modelu bezpieczeństwa i częściowych modeli opartych na systemach progowych typu kolejnych "k z n" zdatnych. Ponadto, zaprezentowano rozważania dotyczące aspektów wyboru metodologii do oceny ryzyka trasy statku.