Wyniki wyszukiwania - Biblioteka Nauki

1

Advances in risk analysis in railway signalling

100%

Jensen B. , Griebel S.

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tom Vol. 3, No. 1

101--108

EN

The paper is concerned with the developments of risk analysis during the last decade, starting from full range quantitative risk analysis of e.g. a level crossing based on the CENELEC standards EN50126 and EN50129 up to semi-quantitative methods for risk analysis. To expedite this shift from pure quantitative approaches to a more categorized approach were the perennial challenges of insufficient availability of accurate data and the sheer complexity of the reality to be model quantitatively. The article contains both a presentation of a complete quantitative risk analysis for a level crossing as well as a discussion of the crucial points that will need improvement on the basis of a new semi-quantitative standard for risk analysis that has been issued as a national pre-standard in Germany. The relation to the current regulations stipulated by the European Railway Agency and recent publications on this issue are presented as well.

2

The weight of the eyelens in the European hares of known age

100%

Andersen J. , Jensen B.

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1972

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tom 17

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nr 1-11

3

Ervironmental friendly drilling fluid management offshore Norway

80%

Bilstad T. , Jensen B. , Toft M.

AGH Drilling, Oil, Gas

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2014

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tom Vol. 31, no. 2

191--197

EN

Types and amount of fluids utilized when drilling a well determine to which extent the drilled cuttings are legally considered hazardous waste. The main categories of drilling fluids are oil based (OBM), water based (WBM) and synthetic based mud (SBM). The purpose of adding fluids to the drilling operations is to cool and lubricate the drill bit, to stabilize the well bore, to control subsurface pressure, to control formation pressure, to control well stability. to control corrosion, and to carry cuttings to the surface. Historically, cuttings from drilling sub-surface wells have been depositeddirectly from the platform to the seabed. However, environmental laws and regulations for the Norwegian offshore sector prohibit such practice when the oil on cutting exceeds 1 % by weight. Re-injection of cuttings as a slurry into subsurface formations is still practiced. Due to migration, leaks, re-entering of slurry onto the seabed, and collapsing formations this disposal method is on a decline. Transport of oily cuttings to shore for final treatment is the preferred Norwegian practice. However, cutting treatment on platforms is also continuousl yevaluated. For logistics and cost reasons, as well as health, safety and environmental (HSE) and working environment reasons, emphasis is put on offshore waste minimization, reuse and recycle.Ten onshore locations in Norway are currently receiving cuttings for further treatment and fluid recovery. The treated cuttings are for the most part disposed in landfills.

4

Non-chemical methods for controlling seedborne fungi in carrot with special reference to Alternaria radicina

70%

Szopinska D. , Jensen B. , Knudsen I. M. B. , Tylkowska K. , Dorna H.

Journal of Plant Protection Research

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2010

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tom 50

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nr 2

184-192

EN

The objective of the work was to study the efficacy of carrot seed treatment with antagonistic microorganisms Clonostachys rosea, C. solani, and grapefruit extract (Biosept 33 SL™). Seeds were artificially inoculated with Alternaria radicina spores prior to treatment. The presence of fungi, seed germination and vigour were determined in laboratory tests, whereas seedling emergence and health were determined in sand and soil assays. Clonostachys spp. and grapefruit extract significantly reduced seed infestation with A. radicina and improved seed germination capacity. At a lower concentration of ioculum, treatment with Clonostachys spp. increased percentage of healthy plants in sand assay. At a higher concentration of inoculum, treatment with Biosept 33 SL™ at 0.5% was more effective. Inoculation with pathogen and, in most cases, the following treatments, did not affect total plant emergence in a soil assay. However, pathogen affected significantly a percentage of healthy plants. Treatment with Biosept 33 SL™ at 0.5% as well as with C. rosea increased their numbers significantly at both concentrations of inoculum.

PL

Celem pracy byļo zbadanie efektywności zaprawiania mikroorganizmami antagonistycznymi Clonostachys rosea, C. solani i ekstraktem z grejpfruta (Biosept 33 SL™) nasion marchwi, sztucznie inokulowanych zarodnikami grzyba Alternaria radicina. W testach laboratoryjnych oceniano zasiedlenie nasion przez grzyby, kiełkowanie i wigor, natomiast wschody siewek i ich zdrowotność badano w piasku i uniwersalnym podłożu do wysiewu nasion. Grzyby rodzaju Clonostachys, podobnie jak ekstrakt z grejpfruta, znacząco ograniczyły zasiedlenie nasion przez A. radicina i poprawiały zdolność kiełkowania nasion. Przy mniejszym stężeniu inokulum, zaprawianie nasion Clonostachys spp. zwiększało wschody i udział zdrowych roślin w piasku. Przy większym stężeniu inokulum, bardziej efektywne było zaprawianie preparatem Biosept 33 SL™ o stężeniu 0,5%. Inokulacja nasion patogenem i w większości przypadków zaprawianie, nie miały wpływu na wschody roślin w podłożu do wysiewu nasion, ale patogen wpływał istotnie na ich zdrowotność. Niezależnie od stężenia inokulum zaprawianie nasion preparatem Biosept 33 SL™ w stężeniu 0,5% oraz grzybem C. rosea, znacząco zwiększało liczbę zdrowych roślin.

5

Effects of soil disturbance and disease on the growth and reproduction of Lolium perenne L. (Poaceae) introduced into semi-natural grasslands

70%

Erneberg M. , Strandberg B. , Strandberg M. , Jensen B. , Weiner J.

Polish Journal of Ecology

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2008

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tom Vol. 56, nr 4

593-604

EN

We performed manipulative field experiments to investigate the effects of soil disturbance and exposure to a fungal plant pathogen, Puccinia coronata (Corda), on the establishment and spread of two introduced, cultivated genotypes of perennial ryegrass, Lolium perenne (L.). The two cultivars of L. perenne with different levels of susceptibility to P. coronata were introduced to grassland sites to investigate whether a plant cultivar selected to resist a pathogen shows better establishment in semi-natural plant communities than a susceptible cultivar. At two sites where L. perenne was already present, the addition of L. perenne seeds had no significant effect on the shoot biomass of the species, indicating that these populations were not seed limited. Exposure to the pathogen resulted in disease, and infected L. perenne populations showed increased shoot biomass over the course of the 3 year experiment and at harvest the final year, but no effect on seed production. Reproductive allocation was not affected by disease exposure in disturbed plots, but decreased in the presence of disease in undisturbed plots. The increased biomass observed in the semi-natural plant communities when exposed to the pathogen contrasts with the reduced biomass observed in garden experiments when the two cultivars of L. perenne were exposed to pathogen attack. The surprising positive effect of P. coronata on biomass in semi-natural communities indicates that processes here are more complex than in more intensively managed production systems.

6

Offshore drilled cuttings management

70%

Bilstad T. , Stenberg E. S. , Jensen B. , Larsen T. , Toft M.

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2013

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tom Vol. 30, no. 1

47--50

EN

The search for offshore fossil fuels generates large volumes of drilled cuttings which under certain conditions are defined hazardous, negating disposal at sea. Much of the cuttings end up in onshore landfills. The types of fluids used in well drilling operations determine to which extent the cuttings are considered hazardous. The three main types of fluids are oil based mud (OBM), water based mud (WBM) and synthetic based mud (SBM). The purpose of adding fluids or mud in the drilling operations is to cool and lubricate the drill bit, to stabilize the well bore, to control subsurface pressure, formation pressure, well stability and corrosion, and to carry cuttings to the surface. OBM is based on either diesel or mineral oil. One advantage of OBM is enhanced drilling performance, especially in technical challenging environments. A drawback, however, is the toxicity of OBM, prohibiting discharge of cuttings to the marine environment. Drilled cuttings are rocks produced during drilling operations, becoming coated with drilling fluids. Historically, cuttings have been disposed to sea. However, recent environmental laws and regulations prohibit such practice. Re-injection of cuttings as a slurry into subsurface formations has also been discontinued due to leaks and re-entering of slurry into the bottom waters. Transport of cuttings to shore is therefore the choice. For logistics and cost reasons emphasis is put on offshore waste minimization and reuse/recycle. Total fluid management (TFM) leads to environmental impact reduction (EIR). Minimization of drilling fluids and reuse of fluids lead to cost reduction. Volume of cuttings is reduced through directional drilling and by drilling smaller diameter holes. Synthetic based drilling fluids (SBM) are replacing OBM. Drilling wastes are further separated into a fluid and a solid phase. The solids may be used for road and other construction purposes, whereas the OBM is burned for energy recovery. The purpose of the thermo-mechanical cuttings cleaner (TCC) is to convert hazardous oily cuttings into useful products. TCC facilities are only available onshore in Norway. However, offshore TCC units will in due time be introduced, negating the need for transport of cuttings to shore. Cuttings are allowed disposed to sea when no toxic fluids are attached. TCC separation is accomplished by generating temperatures of 240-300 degrees of Celsius sufficient for evaporation of oil and water from the mineral solids.

7

Development and validation of an operational fast time ship manoeuvring solver to increase navigation efficiency in horizontally restricted waterways

70%

Kazerooni M. F. , Rahimian M. , Tree M. , Womersley T. , Jensen B.

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tom Vol. 17 No. 1

71--76

EN

Growth of demand for containerized cargo shipping has put more ports into pressure to accommodate larger vessels. Considering the limitations on dimensions of navigation channels, this is not feasible unless aiming for significant capital dredging or alternatively creating high precision predictions of vessel motions subjected to environmental forcing and interaction with shallow and restricted waterway. NCOS ONLINE (Nonlinear Channel Optimisation Simulator) is a state of the art navigation support tool which combines DHI’s high level forecast of environmental conditions with mathematical model of ship motions to add an extra level of accuracy in predicting the under-keel clearance and vessel swept path to boost the efficiency of navigation and pilotage within restricted channels. NCOS Manoeuvring Module utilizes an autopilot scheme based on PID (Proportional / Integral / Derivative) controller and Line of Sight Algorithm to FORCE Technology’s SimFlex4 manoeuvring solver for prediction of manoeuvring ship swept path and response, which will effectively bring the accuracy of real time full bridge simulator to fast time operation support tool. In this paper, the result of mathematical model is validated against fullscale measurements of containership transits through Port of Auckland Navigation channel by comparing pilot commands, leeway drift and swept path through output of portable pilotage unit. According to the results the model is found promising to predict the behaviour of human pilots with precision required in operational use. Finally, the swept path and manoeuvring performance of a sample transit is assessed on different environmental conditions and tide stages to evaluate the safe transit windows in operation.

8

Phase angle and vector analysis from multifrequency segmental bioelectrical impedance analysis: new reference data for older adults

61%

Reljic D. , Zarafat D. , Jensen B. , Herrmann H. J. , Neurath M. F. , Konturek P. C. , Zopf Y.

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tom 71

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nr 4