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11.
Ingrid Bouwer Utne 《Journal of Cleaner Production》2009,17(8):724-731
This article introduces Quality Function Deployment (QFD) as a method for improving the environmental performance of the Norwegian fishing fleet. Systems engineering has been introduced as a feasible process for handling sustainability issues in the fisheries, because it contains methods for general system design, operation, and support in a life-cycle perspective. QFD is related to systems engineering as a method for translating stakeholder needs into detailed system requirements at each life-cycle stage. Eco-QFD extends the scope of QFD, and combines QFD, Life-Cycle Cost (LCC), and Life-Cycle Analysis (LCA) to evaluate environmental effects and costs in the system development process. The article assesses the usefulness of Eco-QFD in fisheries management decision-making regarding sustainability in the fishing fleet, and for shipyards in their design of fishing vessels. It is concluded that Eco-QFD may be difficult to use for fisheries management in its present form, due to the complexity of sustainability, and the time and efforts demanded to carry out the analyses. Nevertheless, the structuring of the stakeholder needs and requirements may contribute to improved understanding of the decision-situation. 相似文献
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Hans-Ulrich Schnitzler Elisabeth K. V. Kalko Ingrid Kaipf Alan D. Grinnell 《Behavioral ecology and sociobiology》1994,35(5):327-345
When hunting for fish Noctilio leporinus uses several strategies. In high search flight it flies within 20–50 cm of the water surface and emits groups of two to four echolocation signals, always containing at least one pure constant frequency (CF) pulse and one mixed CF-FM pulse consisting of a CF component which is followed by a frequency-modulated (FM) component. The pure CF signals are the longest, with an average duration of 13.3 ms and a maximum of 17 ms. The CF component of the CF-FM signals averages 8.9 ms, the FM sweeps 3.9 ms. The CF components have frequencies of 52.8–56.2 kHz and the FM components have an average bandwidth of 25.9 kHz. A bat in high search flight reacts to jumping fish with pointed dips at the spot where a fish has broken the surface. As it descends to the water surface the bat shows the typical approach pattern of all bats with decreasing pulse duration and pulse interval. A jumping fish reveals itself by a typical pattern of temporary echo glints, reflected back to the bat from its body and from the water disturbance. In low search flight N. leporinus drops to a height of only 4–10 cm, with body parallel to the water, legs extended straight back and turned slightly downward, and feet cocked somewhat above the line of the legs and poised within 2–4 cm of the water surface. In this situation N. leporinus emits long series of short CF-FM pulses with an average duration of 5.6 ms (CF 3.1 and FM 2.6) and an average pulse interval of 20 ms, indicating that it is looking for targets within a short range. N. leporinus also makes pointed dips during low search flight by rapidly snapping the feet into the water at the spot where it has localized a jumping fish or disturbance. In the random rake mode, N. leporinus drops to the water surface, lowers its feet and drags its claws through the water in relatively straight lines for up to 10m. The echolocation behavior is similar to that of high search flight. This indicates that in this hunting mode N. leporinus is not pursuing specific targets, and that raking is a random or statistical search for surface fishes. When raking, the bat uses two strategies. In directed random rake it rakes through patches of water where fish jumping activity is high. Our interpretation is that the bat detects this activity by echolocation but prefers not to concentrate on a single jumping fish. In the absence of jumping fish, after flying for several minutes without any dips, N. leporinus starts to make very long rakes in areas where it has hunted successfully before (memory-directed random rake). Hunting bats caught a fish approximately once in every 50–200 passes through the hunting area. 相似文献
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Amanda Vincent Ingrid Ahnesjö Anders Berglund 《Behavioral ecology and sociobiology》1994,34(6):435-442
In the pipefish Syngnathus typhle, only males brood embryos in specially developed brood pouches, supplying oxygen and nutrients. Laboratory studies have shown that this elaborate paternal care has led to sex-role reversal in this species: males limit female reproductive rate, females are the primary competitors for mates and males exercise greater selectivity in accepting mates. In the first field study of this pipefish, we describe mating behaviour in the wild and test the hypothesis that temporal variations in the operational sex ratio (OSR) determine sex differences in mating behaviour. Our study comprised two reproductive seasons of two sequential mating periods each, the latter separated by a lengthy interval of male brooding. During mating periods, females displayed to all males without wandering and males moved about searching for females, without reacting to all females. The OSR was least female-biased (or even male-biased) at the onset of the breeding season, when most pipefish were simultaneously available to mate, but became strikingly female-biased as males' pouches were filled. The OSR remained substantially female-biased during the second mating period, because few males became available to remate at any one time. As hypothesised, female-biased OSRs resulted in more female-female meetings. As well, females were above the eelgrass more often than brooding males, thus exposing themselves to conspecifics and/ or predators. In the second year, males arrived earlier than females on the breeding site and male pregnancies were shorter, because of higher water temperatures, so rematings occurred earlier. Males met more often during that year than the previous one, but male competitive interactions were still not observed. The field results support laboratory studies and demonstrate that behaviours associated with female-female competition are more prominent when the OSR is more female-biased.
Correspondence to: A. Vincent 相似文献
19.
Professor Dr Gerhard Bernaschek Akgun Yildiz Aytug Kolankaya Ingrid Stuempflen Josef Deutinger 《黑龙江环境通报》1995,15(11):995-1000
Between 1990 and 1993, 166 cases underwent cordocentesis and were followed for at least the following 4 weeks in the Prenatal Diagnosis and Therapy Centre of Vienna University. The indications for the procedure were structural malformations in 46·4 per cent of the cases, other high-risk diagnoses in 48·8 per cent, and maternal age over 35 years in only 4·8 per cent. We investigated retrospectively all cases of complications resulting in fetal loss or preterm labour. Abortion, intrauterine fetal death, chorioamnionitis, and preterm delivery occurred in 0·6, 5·4, 0·6 and 9·0 per cent of these cases, respectively, adding up to a total of 26 cases (15·7 per cent). Although this rate looks relatively high, 20 of the 26 cases had already displayed signs implying a complicated prognosis. Neither maternal age, gestational age, number of attempts, nor placental location correlated with fetal loss or preterm delivery. Significantly higher rates of fetal loss or preterm delivery were observed when cordocentesis was performed in cases diagnosed as duodenal/intestinal stenosis or hydrops–ascites–hydrothroax/hygroma colli (P=0·0488 and P=0·0005). The frequency of complications did not decrease as the experience of the operators increased. 相似文献
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