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1

Collision–attachment law of lepidolite, feldspar and quartz with bubbles in the combined cationic and anionic collector system

Liu Ziyu, Jiao Fen, Qin Wenqing, Wei Qian

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 155324

EN

The purpose of this study is to explore the collision–attachment law of lepidolite, feldspar and quartz during their interaction with bubbles by particle settlement method and bubble rising method under the action of combined collector. In this study, HQ-330 and dodecylamine were used as combined collector to separate lepidolite, feldspar and quartz by flotation. It also aims to analyse the relationship between collision probability, attachment probability, formation time of three-phase contact line and flotation recovery and the main factors affecting the formation time of three-phase contact line. Experimental results show that when the pH is 7 and the combined collector dosage is 100 mg/L, the separation of lepidolite from feldspar and quartz can be achieved. In the particle settlement experiments, the correlation between collision probability and flotation recovery is low, the correlation between attachment probability and flotation recovery is positive. In the bubble rising experiments, the formation time of three-phase contact line (tTPC) is negatively correlated with flotation recovery, and the combined collector changes tTPC by changing drainage time.

2

Manoeuvring areas to adapt ACAS for the maritime domain

Baldauf M., Mehdi R., Deeb H., Schröder-Hinrichs J. U., Benedict K., Krüger C., Fischer S., Gluch M.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2015

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nr 43 (115)

39--47

EN

Rapidly increasing numbers of ships and ship sizes pose an ever-growing challenge to the maritime industry. Although statistics indicate improved levels of safety in the industry which carries 90% of the world’s trade, the risk of navigational accidents, among other issues, remains a prime concern and priority (EMSA, 2010; 2014). In order to address these concerns, the authors turned to another high-risk industry for inspiration. Specifically, they turned to the aviation industry, which has often been used as a source of comparisons and ideas by researchers in the maritime domain. Keeping up with the trend, the authors of this paper turn to a tried-and-tested system used widely in modern aviation: the Airborne Collision Avoidance System (ACAS). The prime idea behind ACAS is to construct two virtual 3D zones around an aircraft. These zones are dynamic, and depend on the manoeuvring characteristics of a given aircraft. If the system detects an “intruder” (another aircraft) in either of the two well-defined virtual zones, it provides warnings and/or instructions to pilots of both aircraft to take certain precautionary or emergency measures. In the current paper, the authors explore whether or not such a system is feasible for use in the maritime domain and, if so, how. The paper provides a detailed analysis of the potential benefits and drawbacks of using an ACAS-like system onboard vessels. It also discusses possible means of implementation and integration with current equipment, and explores how the introduction of e-navigation may impact the proposed solution.

3

Model of navigational safety of vessels in Polish EEZ

Przywarty M., Jarząbek D., Gucma L.

Annual of Navigation

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2014

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No. 21

133--142

EN

The paper presents the assumptions of a simulation model for assessing the navigational safety of fishing vessels. The model consist of submodels of merchant and fishing vessels traffic, submodel of external condition and submodel of accident consequences. Paper present also a results of simulation experiment which was carried out for Polish EEZ. Model takes into account all Polish fishing vessels operating in the Polish EEZ with length more than 15 meters and the merchant vessels traffic in South Baltic Sea area. As a results positions of simulated collisions of fishing and merchant vessels, positions and sizes of simulated bunker spills and the positions of losses of fishing equipment were achieved.

PL

W artykule przedstawiono założenia złożonego modelu symulacyjnego dla szacowania bezpieczeństwa nawigacyjnego statków rybackich. Model składa się z modeli ruchu statków handlowych i statków rybackich, modelu warunków środowiskowych oraz modelu skutków zdarzenia. Ponadto w artykule przedstawiono rezultaty eksperymentu symulacyjnego przeprowadzonego dla polskiej wyłącznej strefy ekonomicznej. Model uwzględnia wszystkie polskie statki rybackie operujące w polskiej wyłącznej strefie ekonomicznej o długości większej niż piętnaście metrów oraz ruch statków handlowych na południowej części Morza Bałtyckiego. W rezultacie otrzymano pozycje prawdopodobnych kolizji statków transportowych oraz rybackich, pozycje i rozmiary prawdopodobnych rozlewów olejowych oraz pozycje utraty narzędzi połowowych.

4

Modelling the accident probability in large-scale, maritime transportation system

Blokus-Roszkowska A., Montewka J., Smolarek J.

Journal of Polish Safety and Reliability Association

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2012

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Vol. 3, No. 2

237--244

EN

The probability of an accident in transportation systems can serve as a measure of these systems safety or risk, depending on the objective. Therefore numerous methods and models for risk evaluation, with respect to maritime, have been developed. However, these models are either too simplified, allowing relatively fast analysis but very often missing the substantial links among the model variables, or they are too slow for effective analysis, due to computational complexity, not necessarily being backed-up with the complexity of the model itself. Thereby, this paper introduces a novel method evaluating the probability of ship-ship collision in the maritime transportation system focusing on the open sea collisions, applying the queuing theory in the simulation model. The model allows relatively fast prediction as it focuses on the specific events (e.g. accidents), instead of simulating the whole traffic. To support this hypothesis a case study is presented focusing on a selected element of transportation system in operation.

5

Predicting risk of collision for oil tankers in the Gulf of Finland

Montewka J.

Journal of KONBiN

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2009

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No. 3-4 (11-12)

17-32

EN

The Gulf of Finland (GOF) is considered one of the most dense place in the world in terms of marine traffic, and in addition to the Danish Straits it forms the narrowest and shallowest waters in the Baltic Sea. As the volume of shipping in the GOF increases constantly, so does the risk of accidents. This paper presents a model for risk assessment for vessels colliding with emphasis put on tankers. A new adaptation of pre-existent physical model based on molecular collision theory for probability of collision assessment is presented. The consequences of an accident are expressed in the monetary terms, and concern the costs due to an oil spill. Neither loss of humans' life nor structural damages were considered in the presented risk model. The risk that colliding tankers pose are assessed for winter and traffic summer profiles separately.

PL

Zatoka Fińska jest uważana za jedno z tych miejsc na świecie, które charakteryzują się największą intensywnością ruchu morskiego, a oprócz Cieśnin Duńskich stanowi najwęższy i najpłytszy szlak wodny w akwenie Morza Bałtyckiego. Ponieważ intensywność ruchu statków na obszarze Zatoki Fińskiej ciągle rośnie, zwiększa się również ryzyko wypadków. W niniejszym artykule przedstawiono model dla oceny ryzyka związanego z kolizją statków, ze szczególnym uwzględnieniem tankowców. Przedstawiono nowe zastosowanie znanego wcześniej modelu fizycznego opartego na teorii kolizji molekularnych oraz użycie tego modelu do oceny prawdopodobieństwa kolizji statków. Konsekwencje takiego wypadku są wyrażone jako koszty materialne i związane są ze stratami spowodowanymi przez wyciek ropy. W zaprezentowanym modelu ryzyka nie uwzględnia się start życia ludzkiego ani szkód materialnych poniesionych przez armatorów. Ryzyko związane z kolizją tankowców oceniono oddzielnie dla letniego i zimowego profilu pogodowego.