Application and Advantages of Catamarans for Coastal Patrol Vessels

1996 ◽  
Vol 33 (02) ◽  
pp. 108-118
Author(s):  
Robert G. Allan

Although the catamaran hull has been, for the past decade, the predominant choice for ferry designs of increasingly larger dimensions, as well as other applications, its adoption for small patrol craft has been limited. This paper describes the advantages and applicability of the catamaran for typical patrol boat missions, assesses its capital and operating costs versus those of a monohull of equivalent performance, and reviews the experience of a standard series of catamaran patrol boats operating in offshore British Columbia waters by the Royal Canadian Mounted Police. RCMP Commissioner class patrol vessels at speed

Author(s):  
Tom Novecosky

NOVA’s Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, United States and British Columbia. It is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level which allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).


1994 ◽  
Vol 116 (1) ◽  
pp. 152-155 ◽  
Author(s):  
T. Novecosky

NOVA’s Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, United States, and British Columbia. There is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level that allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).


2005 ◽  
Vol 40 (4) ◽  
pp. 418-430 ◽  
Author(s):  
Markus L. Heinrichs ◽  
Brian F. Cumming ◽  
Kathleen R. Laird ◽  
J. Sanford Hart

Abstract Diatom and chironomid analysis of sediments encompassing the past 400 years from Bouchie Lake, British Columbia, suggests two distinct periods of limnological conditions. Prior to 1950 AD, Fragilaria construens and F. pinnata are the most common diatom species, and Chironomus, Procladius and Tanytarsini dominate the chironomid record. Moderately low nutrient concentrations consistent with oligo-mesotrophic lakes are inferred. From 1950, the diatom assemblage is dominated by Stephanodiscus parvus, a eutrophic indicator, whereas the chironomid communities show a relative increase in littoral taxa coincident with lower head capsule abundance. Higher nutrient levels, specifically total phosphorus, which increased from 8 µg L-1 prior to 1950 to 20 µg L-1 currently, are coincident with midge communities indicative of lower oxygen concentrations. Observed biotic changes and nutrient levels inferred from the sediment core correspond to historical land-use changes.


1995 ◽  
Vol 11 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Brian F. Atwater ◽  
Alan R. Nelson ◽  
John J. Clague ◽  
Gary A. Carver ◽  
David K. Yamaguchi ◽  
...  

Earthquakes in the past few thousand years have left signs of land-level change, tsunamis, and shaking along the Pacific coast at the Cascadia subduction zone. Sudden lowering of land accounts for many of the buried marsh and forest soils at estuaries between southern British Columbia and northern California. Sand layers on some of these soils imply that tsunamis were triggered by some of the events that lowered the land. Liquefaction features show that inland shaking accompanied sudden coastal subsidence at the Washington-Oregon border about 300 years ago. The combined evidence for subsidence, tsunamis, and shaking shows that earthquakes of magnitude 8 or larger have occurred on the boundary between the overriding North America plate and the downgoing Juan de Fuca and Gorda plates. Intervals between the earthquakes are poorly known because of uncertainties about the number and ages of the earthquakes. Current estimates for individual intervals at specific coastal sites range from a few centuries to about one thousand years.


1993 ◽  
Vol 115 (1) ◽  
pp. 1-8 ◽  
Author(s):  
D. G. Waugaman ◽  
A. Kini ◽  
C. F. Kettleborough

This paper describes recent published design advances that have been made in desiccant cooling systems. In desiccant cooling cycles, the desiccant reduces the humidity of the air by removing moisture from the air. Then the temperature is reduced by other components such as heat exchangers, evaporative coolers, or conventional cooling coils. The main advantage that desiccant cooling systems offer is the capability of using low-grade thermal energy. Desiccant cooling systems for residential and commercial applications are now being used to reduce energy-operating costs. However, the initial costs are comparatively high. The focus of research for the past decade has been to develop desiccant systems with a high coefficient of performance. Recent studies have emphasized computer modeling and hybrid systems that combine desiccant dehumidifiers with conventional systems.


1964 ◽  
Vol 86 (2) ◽  
pp. 97-104 ◽  
Author(s):  
David Migdal ◽  
John J. Horgan

Supersonic transports will require jet-engine thrust nozzles that are highly efficient from take-off to supersonic cruise in order to minimize the direct operating costs. Variable-area ejectors, plug nozzles, and modifications of these basic types have been tested extensively during the past several years. Performance trends for these nozzles are presented with the emphasis on external flow effects. A new ejector which utilizes aerodynamically actuated doors to admit external air into the ejector shroud is discussed.


1996 ◽  
Vol 70 (2) ◽  
pp. 280-293 ◽  
Author(s):  
Desmond Collins

The remarkable “evolution” of the reconstructions of Anomalocaris, the extraordinary predator from the 515 million year old Middle Cambrian Burgess Shale of British Columbia, reflects the dramatic changes in our interpretation of early animal life on Earth over the past 100 years. Beginning in 1892 with a claw identified as the abdomen and tail of a phyllocarid crustacean, parts of Anomalocaris have been described variously as a jellyfish, a sea-cucumber, a polychaete worm, a composite of a jellyfish and sponge, or have been attached to other arthropods as appendages. Charles D. Walcott collected complete specimens of Anomalocaris nathorsti between 1911 and 1917, and a Geological Survey of Canada party collected an almost complete specimen of Anomalocaris canadensis in 1966 or 1967, but neither species was adequately described until 1985. At that time they were interpreted by Whittington and Briggs to be representatives of “a hitherto unknown phylum.”Here, using recently collected specimens, the two species are newly reconstructed and described in the genera Anomalocaris and Laggania, and interpreted to be members of an extinct arthropod class, Dinocarida, and order Radiodonta, new to science. The long history of inaccurate reconstruction and mistaken identification of Anomalocaris and Laggania exemplifies our great difficulty in visualizing and classifying, from fossil remains, the many Cambrian animals with no apparent living descendants.


Author(s):  
David Ehrenfeld

When we arrived in Vancouver at the start of our vacation, the tabloid headline at the newspaper stand caught our attention. “World’s Bravest Mom,” it shrieked. We stopped to read. The story was simple; it needed no journalistic embellishment. Dusk, August 19, 1996. Mrs. Cindy Parolin is horseback riding with her four children in Tulameen, in southern British Columbia’s Okanagan region. Without warning, a cougar springs out of the vegetation, hurtling at the neck of one of the horses. In the confusion, Steven Parolin, age six, falls off his horse and is seized by the cougar. Mrs. Parolin, armed only with a riding crop, jumps off her horse and challenges the cougar, which drops the bleeding child and springs at her. Ordering her other children to take their wounded brother and go for help, Mrs. Parolin confronts the cougar alone. By the time rescuers reach her an hour later, she is dying. The cat, shot soon afterward, was a small one, little more than sixty pounds. Adult male cougars can weigh as much as 200 pounds, we learn the next day from the BC Environment’s pamphlet entitled “Safety Guide to Cougars.” We are on our way to Garibaldi Provincial Park, where we plan to do some hiking, and have stopped in the park head-quarters for information. “Most British Columbians live all their lives without a glimpse of a cougar, much less a confrontation with one,” says the pamphlet, noting that five people have been killed by cougars in British Columbia in the past hundred years. (Actually, the number is now higher; cougar attacks have become increasingly common in the western United States and Canada in recent years.) “Seeing a cougar should be an exciting and rewarding experience, with both you and the cougar coming away unharmed.”However, the pamphlet notes, cougars seem to be attracted to children as prey, possibly because of “their high-pitched voices, small size, and erratic movements.” When hiking, “make enough noise to prevent surprising a cougar . . . carry a sturdy walking stick to be used as a weapon if necessary,” and “keep children close-at-hand and under control.”


SAGE Open ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 215824401989908 ◽  
Author(s):  
Krista Stelkia

Independent oversight of Canadian police has increased over the past decade in response to a number of high-profile cases of police misconduct and public dissatisfaction with internal police investigations. To date, however, the dynamics of the oversight process have not been subjected to critical analysis. This study examines the benefits and challenges of the oversight systems for the Royal Canadian Mounted Police (RCMP) and municipal police in British Columbia, Canada, as well as the role of oversight in increasing police accountability, improving public confidence, and modifying police behavior. Drawing on semi-structured interviews with persons ( n = 13) from oversight agencies, police unions, special interest groups, and professional standards units, the study found that despite having one of the most progressive oversight models in Canada, the system faces major challenges. These include slow processing of complaints, the administrative burden of minor complaints, the difficulty in determining return on investment, and the two-tier complaint model.


1969 ◽  
Vol 45 (1) ◽  
pp. 5-13
Author(s):  
George A. Garratt

Stimulated most recently by the reorganization of the post-secondary education systems in British Columbia, Ontario, and Quebec, the number of formal forest-technician training programs has now increased to 17, two-thirds of them two-year offerings, with several additional courses in prospect for 1969. Enrollments have shown a rather consistent increase over the past six years, as a consequence both of the initiation of 13 new programs during that period and of enlarged student bodies in the older establishments. The number of forest-technician diploma awards reached an all-time high of 472 in 1968, to give a ratio of 4.4 technicians per professional (B.Sc.F.) degree recipient. About two-thirds of the 1968 graduates who entered forestry work were employed by provincial agencies, approximately a fourth were hired by the forest industries, and the balance entered federal service.


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