The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform
W J Frith - One of the best experts on this subject based on the ideXlab platform.
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The relative Effectiveness of a hidden versus a visible speed camera programme
Accident Analysis & Prevention, 2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Abstract Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called ‘speed camera areas’) which are mainly road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four Police regions. This trial was still in progress at the time of writing and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden cameras and related publicity were found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties both in speed camera areas and on 100 km/h speed limit roads generally. There were initial changes in public attitudes in response to the programme that later largely reverted to pre-trial levels. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. As further crash, speed and attitude data become available, the longer-term Effects of the hidden camera programme will be evaluated.
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The relative Effectiveness of hidden versus visible speed cameras
2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly-operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to some 1,200 sites which are specific signed road sections with a record of speed-related crashes. A trial of hidden speed cameras took place between mid-1997 and mid-2000 in 100 km/h speed limit areas in one of New Zealand's four Police regions. Camera operation remained overt elsewhere. After the trial, camera operation in the trial area reverted to the previous overt system. This paper reports the results of an evaluation of the first two years of the trial. During the first two years, the hidden camera programme was found to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. These changes in speeds, crashes and casualties were identified in the trial area in comparison with a control area where generally highly visible speed camera enforcement continued to be used. Despite compelling evidence of changes in drivers' speeding behaviour, which was the ultimate objective of hiding the cameras, initial changes in public attitudes associated with the trial later reverted to pre-trial levels. The four-fold increase in speed camera tickets issued in the trial area was an expected consequence of hiding the cameras and as such, an integral part of the hidden camera programme.
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THE RELATIVE EffectIVENESS OF HIDDEN VERSUS VISIBLE SPEED CAMERAS
1999Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called "speed camera areas") which are generally road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four police regions. This trial is still in progress and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden camera programme was found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. Crash and casualty rates and speeds are continually being monitored to evaluate the longer-term Effects of the hidden camera programme. (a) For the covering entry of this conference, please see ITRD abstract no. E202275.
Stuart Banks - One of the best experts on this subject based on the ideXlab platform.
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SeaWiFS satellite monitoring of oil spill impact on primary production in the Galápagos Marine Reserve.
Marine pollution bulletin, 2020Co-Authors: Stuart BanksAbstract:Near daily satellite monitoring of ocean colour using sea viewing wide angle of field viewing sensor (SeaWiFS) allowed the oceanic and near coastal chlorophyll-a distributions to be followed across the Galápagos Marine Reserve (GMR) from space. In the aftermath of the Jessica spill early indications suggested that, compared to the three preceding years 1998-2000, local chlorophyll concentrations over January 2001 were elevated across the Galápagos Marine Reserve [Biological Impacts of the Jessica Oil Spill on the Galápagos Environment: Preliminary Report. Charles Darwin Foundation, Puerto Ayora, Galápagos, Ecuador, 2001]. At the time of the spill the central and eastern extent of the archipelago was experiencing a spatially extensive moderate bloom event (0.5-2.5 mgm(-3) chl-a) extending over the central islands, including the source of the spill and areas of known impact such as the islands of Santa Fé, eastern Santa Cruz and Floreana directly in the advection path.Further investigation shows that chlorophyll across the affected regions of western San Cristóbal, Santa Fé, southeast Santa Cruz, eastern Floreana and eastern Isabela declined in the week directly following the spill event, yet rose in the successive month to levels analogous to preceding years. Although there may have been a Localised Effect of the spill upon near coast phytoplankton primary production in the short term, the observed variance in the weeks following the spill was not significant in comparison to the normal high variation between years and within the El Niño/Southern Oscillation signal.
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SeaWiFS satellite monitoring of oil spill impact on primary production in the Galápagos Marine Reserve.
Marine Pollution Bulletin, 2003Co-Authors: Stuart BanksAbstract:Abstract Near daily satellite monitoring of ocean colour using sea viewing wide angle of field viewing sensor (SeaWiFS) allowed the oceanic and near coastal chlorophyll-a distributions to be followed across the Galapagos Marine Reserve (GMR) from space. In the aftermath of the Jessica spill early indications suggested that, compared to the three preceding years 1998–2000, local chlorophyll concentrations over January 2001 were elevated across the Galapagos Marine Reserve [Biological Impacts of the Jessica Oil Spill on the Galapagos Environment: Preliminary Report. Charles Darwin Foundation, Puerto Ayora, Galapagos, Ecuador, 2001]. At the time of the spill the central and eastern extent of the archipelago was experiencing a spatially extensive moderate bloom event (0.5–2.5 mg m−3 chl-a) extending over the central islands, including the source of the spill and areas of known impact such as the islands of Santa Fe, eastern Santa Cruz and Floreana directly in the advection path. Further investigation shows that chlorophyll across the affected regions of western San Cristobal, Santa Fe, southeast Santa Cruz, eastern Floreana and eastern Isabela declined in the week directly following the spill event, yet rose in the successive month to levels analogous to preceding years. Although there may have been a Localised Effect of the spill upon near coast phytoplankton primary production in the short term, the observed variance in the weeks following the spill was not significant in comparison to the normal high variation between years and within the El Nino/Southern Oscillation signal.
D.d Patil - One of the best experts on this subject based on the ideXlab platform.
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Classification evaluation of water injected hydrocyclone
Minerals Engineering, 1999Co-Authors: D.d PatilAbstract:Abstract The performance of hydrocyclone with a truncated cone and water injection facility at its apex has been studied. It was found that the flow rate of water in the overflow of the cyclone is higher when smaller cone is used. However on injecting water at the apex, the overflow water rate is minimum when smallest cone is used, implying Localised Effect of injection of water in the displacement of fines. Experiments using silica as feed, along with water injection, showed that the weight percent of particles less than a particular size in the underflow is reduced, this size being a function of inlet pressure and truncated cone diameter.
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Classification evaluation of water injected hydrocyclone
Minerals Engineering, 1999Co-Authors: D.d Patil, T.c RaoAbstract:The performance of hydrocyclone with a truncated cone and water injection facility at its apex has been studied. It was found that the flow rate of water in the overflow of the cyclone is higher when smaller cone is used. However on injecting water at the apex, the overflow water rate is minimum when smallest cone is used implying Localised Effect of injection of water in the displacement of fines. Experiments using silica as feed, along with water injection showed that the weight percent of particles less than a particular size in the under flow is reduced this size being a function of inlet pressure and truncated cone diameter. (C) 1999 Elsevier Science Ltd. All rights reserved.
Michael Keall - One of the best experts on this subject based on the ideXlab platform.
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The relative Effectiveness of a hidden versus a visible speed camera programme
Accident Analysis & Prevention, 2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Abstract Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called ‘speed camera areas’) which are mainly road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four Police regions. This trial was still in progress at the time of writing and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden cameras and related publicity were found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties both in speed camera areas and on 100 km/h speed limit roads generally. There were initial changes in public attitudes in response to the programme that later largely reverted to pre-trial levels. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. As further crash, speed and attitude data become available, the longer-term Effects of the hidden camera programme will be evaluated.
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The relative Effectiveness of hidden versus visible speed cameras
2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly-operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to some 1,200 sites which are specific signed road sections with a record of speed-related crashes. A trial of hidden speed cameras took place between mid-1997 and mid-2000 in 100 km/h speed limit areas in one of New Zealand's four Police regions. Camera operation remained overt elsewhere. After the trial, camera operation in the trial area reverted to the previous overt system. This paper reports the results of an evaluation of the first two years of the trial. During the first two years, the hidden camera programme was found to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. These changes in speeds, crashes and casualties were identified in the trial area in comparison with a control area where generally highly visible speed camera enforcement continued to be used. Despite compelling evidence of changes in drivers' speeding behaviour, which was the ultimate objective of hiding the cameras, initial changes in public attitudes associated with the trial later reverted to pre-trial levels. The four-fold increase in speed camera tickets issued in the trial area was an expected consequence of hiding the cameras and as such, an integral part of the hidden camera programme.
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THE RELATIVE EffectIVENESS OF HIDDEN VERSUS VISIBLE SPEED CAMERAS
1999Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called "speed camera areas") which are generally road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four police regions. This trial is still in progress and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden camera programme was found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. Crash and casualty rates and speeds are continually being monitored to evaluate the longer-term Effects of the hidden camera programme. (a) For the covering entry of this conference, please see ITRD abstract no. E202275.
Lynley J Povey - One of the best experts on this subject based on the ideXlab platform.
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The relative Effectiveness of a hidden versus a visible speed camera programme
Accident Analysis & Prevention, 2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Abstract Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called ‘speed camera areas’) which are mainly road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four Police regions. This trial was still in progress at the time of writing and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden cameras and related publicity were found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties both in speed camera areas and on 100 km/h speed limit roads generally. There were initial changes in public attitudes in response to the programme that later largely reverted to pre-trial levels. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. As further crash, speed and attitude data become available, the longer-term Effects of the hidden camera programme will be evaluated.
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The relative Effectiveness of hidden versus visible speed cameras
2001Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly-operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to some 1,200 sites which are specific signed road sections with a record of speed-related crashes. A trial of hidden speed cameras took place between mid-1997 and mid-2000 in 100 km/h speed limit areas in one of New Zealand's four Police regions. Camera operation remained overt elsewhere. After the trial, camera operation in the trial area reverted to the previous overt system. This paper reports the results of an evaluation of the first two years of the trial. During the first two years, the hidden camera programme was found to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. These changes in speeds, crashes and casualties were identified in the trial area in comparison with a control area where generally highly visible speed camera enforcement continued to be used. Despite compelling evidence of changes in drivers' speeding behaviour, which was the ultimate objective of hiding the cameras, initial changes in public attitudes associated with the trial later reverted to pre-trial levels. The four-fold increase in speed camera tickets issued in the trial area was an expected consequence of hiding the cameras and as such, an integral part of the hidden camera programme.
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THE RELATIVE EffectIVENESS OF HIDDEN VERSUS VISIBLE SPEED CAMERAS
1999Co-Authors: Michael Keall, Lynley J Povey, W J FrithAbstract:Overtly operated mobile speed cameras have been used in New Zealand since late 1993. Their operation has been confined to specific sites (called "speed camera areas") which are generally road sections with a record of speed-related crashes. A trial of hidden speed cameras began in mid-1997 in 100 km/h speed limit areas in one of New Zealand's four police regions. This trial is still in progress and the current paper reports the results of an evaluation of the first year of the trial. During that period, the hidden camera programme was found (compared with the generally highly visible speed camera enforcement in the rest of New Zealand) to be associated with net falls in speeds, crashes and casualties - both in speed camera areas and on 100 km/h speed limit roads generally - along with changes in public attitudes to speed and speed enforcement. Compared with the Localised Effect of visible cameras on speeds and crashes mainly in speed camera areas, the hidden cameras had a more general Effect on all roads. Crash and casualty rates and speeds are continually being monitored to evaluate the longer-term Effects of the hidden camera programme. (a) For the covering entry of this conference, please see ITRD abstract no. E202275.
