The aspect of compatibility between large and small cars has become a main topic in recent accide... more The aspect of compatibility between large and small cars has become a main topic in recent accident research. The likelihood of collisions between vehicles of considerable different size is triggering latest discussion on new legal requirements and test procedures. Computer modelling applicable in crashworthiness has advanced substantially due to the availability of mature software and powerful hardware. Design guide lines derived from these calculations are no longer restricted to A-B comparisons and rough trend analyses. This paper describes a compatibility study based on full scale finite element and lumped mass model calculations involving models exceeding 140000 elements. A head-on car-to-car offset crash is compared to a car-to-deformable-barrier simulation. The cars have a weight ratio of approximately 1.5:1. The efforts of obtaining a single deformable barrier which gives similar deformation and deceleration profiles for both vehicles as in the case of the car-to-car collisi...
Tropical estuarine fishes are inextricably linked with mangroves, which are the dominant vegetati... more Tropical estuarine fishes are inextricably linked with mangroves, which are the dominant vegetation of tropical and subtropical estuaries. Among the most produc-tive of aquatic areas and heavily exploited, their future may depend upon ecosystem understanding. This ...
Canadian Journal of Fisheries and Aquatic Sciences, 2007
We describe a Bayesian modelling approach to estimate abundance and biomass of pelagic fishes fro... more We describe a Bayesian modelling approach to estimate abundance and biomass of pelagic fishes from gillnet catches in data-limited situations. By making a number of simple assumptions, we use fish sustained swimming speed to calculate the effective area fished by a gillnet in a specified soak time to estimate abundance (fish·km–2) from the number of fish caught. We used catch data from various sampling methods in northern Australia and elicited anecdotal information from experts to build a size distribution of the true population to compensate for size classes that were unlikely to be represented in the catch because of size selectivity of the gear. Our final abundance estimates for various-sized scombrids (0.04–4.17 fish·km–2) and istiophorids (0.004–0.005 fish·km–2) were similar to what has been estimated for similar species in more data-rich situations in tropical regions of the Pacific Ocean. The model is particularly useful in data-limited situations in which abundance or bioma...
Tropical estuarine areas comprise small systems of a few km, larger estuaries, coastal lakes of h... more Tropical estuarine areas comprise small systems of a few km, larger estuaries, coastal lakes of hundreds of km 2 and vast shallow coastal waters that are contiguous with estuaries and have similar reduced salinities. Many of the world's great estuaries are in the tropics, eg the ...
The demersal fish fauna of the Gulf of Carpentaria was surveyed during November and December 1990... more The demersal fish fauna of the Gulf of Carpentaria was surveyed during November and December 1990. Over 300 species from 85 families were caught by trawling a systematic grid of 107 stations. The absolute mean biomass was 124.8 kg ha-1 (s.e. =44.1) for day trawls and 53.7 kg ha-1 (s.e. =6.0) for night trawls. The overall mean catch rates were 421.3 kg h-1 (s.e. = 128.5) for day trawls and 198.6 kg h-1 (s.e. =21.5) for night trawls. Biomasses were twice as high in the prawn-trawling grounds of Albatross Bay, the south-eastern gulf and Groote Eylandt as they were elsewhere in the gulf. Twenty-five species made up 75% of the biomass; the dominant families were Haemulidae, Carangidae, Leiognathidae and Nemipteridae. Community-structure and distribution patterns were analysed by numerical classification techniques and principal-coordinates analysis. These indicated six main site groups and 15 fish community groups, based on fish species occurrences and biomasses. There was a relationship...
Page 1. Env. Biol. Fish., Vol. 1, No. 2, pp. 197-204, 1977. Tbe biology of tbe burrowing goby Cro... more Page 1. Env. Biol. Fish., Vol. 1, No. 2, pp. 197-204, 1977. Tbe biology of tbe burrowing goby Croilia mossambica Smith (Teleostei, Gobiidae) Stephen JM Blaber & Alan K. Whitfield Zoology Department, University of Natal, Pietermaritzburg, Natal, South Africa ...
Page 1. tnv. Biol. Fish. Vol. 3, No. 3, pp. 293-296, 1978 Resource segregation among iliophagous ... more Page 1. tnv. Biol. Fish. Vol. 3, No. 3, pp. 293-296, 1978 Resource segregation among iliophagous fish in Lake St. Lucia, Zululand Alan K. Whitfield & Stephen J. M. Blaber Zoology Department, University of Natal, Pietermaritzburg, Natal, South Africa ...
The aspect of compatibility between large and small cars has become a main topic in recent accide... more The aspect of compatibility between large and small cars has become a main topic in recent accident research. The likelihood of collisions between vehicles of considerable different size is triggering latest discussion on new legal requirements and test procedures. Computer modelling applicable in crashworthiness has advanced substantially due to the availability of mature software and powerful hardware. Design guide lines derived from these calculations are no longer restricted to A-B comparisons and rough trend analyses. This paper describes a compatibility study based on full scale finite element and lumped mass model calculations involving models exceeding 140000 elements. A head-on car-to-car offset crash is compared to a car-to-deformable-barrier simulation. The cars have a weight ratio of approximately 1.5:1. The efforts of obtaining a single deformable barrier which gives similar deformation and deceleration profiles for both vehicles as in the case of the car-to-car collisi...
Tropical estuarine fishes are inextricably linked with mangroves, which are the dominant vegetati... more Tropical estuarine fishes are inextricably linked with mangroves, which are the dominant vegetation of tropical and subtropical estuaries. Among the most produc-tive of aquatic areas and heavily exploited, their future may depend upon ecosystem understanding. This ...
Canadian Journal of Fisheries and Aquatic Sciences, 2007
We describe a Bayesian modelling approach to estimate abundance and biomass of pelagic fishes fro... more We describe a Bayesian modelling approach to estimate abundance and biomass of pelagic fishes from gillnet catches in data-limited situations. By making a number of simple assumptions, we use fish sustained swimming speed to calculate the effective area fished by a gillnet in a specified soak time to estimate abundance (fish·km–2) from the number of fish caught. We used catch data from various sampling methods in northern Australia and elicited anecdotal information from experts to build a size distribution of the true population to compensate for size classes that were unlikely to be represented in the catch because of size selectivity of the gear. Our final abundance estimates for various-sized scombrids (0.04–4.17 fish·km–2) and istiophorids (0.004–0.005 fish·km–2) were similar to what has been estimated for similar species in more data-rich situations in tropical regions of the Pacific Ocean. The model is particularly useful in data-limited situations in which abundance or bioma...
Tropical estuarine areas comprise small systems of a few km, larger estuaries, coastal lakes of h... more Tropical estuarine areas comprise small systems of a few km, larger estuaries, coastal lakes of hundreds of km 2 and vast shallow coastal waters that are contiguous with estuaries and have similar reduced salinities. Many of the world's great estuaries are in the tropics, eg the ...
The demersal fish fauna of the Gulf of Carpentaria was surveyed during November and December 1990... more The demersal fish fauna of the Gulf of Carpentaria was surveyed during November and December 1990. Over 300 species from 85 families were caught by trawling a systematic grid of 107 stations. The absolute mean biomass was 124.8 kg ha-1 (s.e. =44.1) for day trawls and 53.7 kg ha-1 (s.e. =6.0) for night trawls. The overall mean catch rates were 421.3 kg h-1 (s.e. = 128.5) for day trawls and 198.6 kg h-1 (s.e. =21.5) for night trawls. Biomasses were twice as high in the prawn-trawling grounds of Albatross Bay, the south-eastern gulf and Groote Eylandt as they were elsewhere in the gulf. Twenty-five species made up 75% of the biomass; the dominant families were Haemulidae, Carangidae, Leiognathidae and Nemipteridae. Community-structure and distribution patterns were analysed by numerical classification techniques and principal-coordinates analysis. These indicated six main site groups and 15 fish community groups, based on fish species occurrences and biomasses. There was a relationship...
Page 1. Env. Biol. Fish., Vol. 1, No. 2, pp. 197-204, 1977. Tbe biology of tbe burrowing goby Cro... more Page 1. Env. Biol. Fish., Vol. 1, No. 2, pp. 197-204, 1977. Tbe biology of tbe burrowing goby Croilia mossambica Smith (Teleostei, Gobiidae) Stephen JM Blaber & Alan K. Whitfield Zoology Department, University of Natal, Pietermaritzburg, Natal, South Africa ...
Page 1. tnv. Biol. Fish. Vol. 3, No. 3, pp. 293-296, 1978 Resource segregation among iliophagous ... more Page 1. tnv. Biol. Fish. Vol. 3, No. 3, pp. 293-296, 1978 Resource segregation among iliophagous fish in Lake St. Lucia, Zululand Alan K. Whitfield & Stephen J. M. Blaber Zoology Department, University of Natal, Pietermaritzburg, Natal, South Africa ...
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