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181.
The results from a survey of Swedish commercial fishers on regulation compliance and attitudes to control and restrictions are reported. According to the responding fishers, 90% of all Swedish catches are reported, in spite of limited control efforts. From an economic perspective we would expect substantially lower levels of compliance. The results also show that the majority of Swedish fishers are in favour of co-management on a regional basis. However, on this and other management issues opinions divert significantly between large vessel operators and small vessel operators, which reveals conflicting interests for such and similar changes in Swedish management of fisheries.  相似文献   
182.
This paper presents the review and studies at various levels of problems concerning the authors’ previous research on the dynamics of vehicle–deck interactions. The various levels of study include the dynamic structural behavior of vehicle–deck systems, vehicle vibrations, damping effects of vehicles on structural systems, dynamic interactions between tire and deck surface, and vehicle securing on decks during ship motions, etc. The study includes analytical, numerical and experimental analysis. Practical problems encountered by Ro–Ro ship designers are addressed by discussing those analysis. It is shown that influences from the dynamics of vehicle–deck interactions are relevant to a number of aspects of issues, such as the excitation frequency range, how detailed information of the structural system response is required, the structure characteristics, and positions and orientations of vehicles on decks, etc. The study contributes to the knowledge for the naval architect and vehicle engineer on how significant the dynamics of vehicle–deck interactions are when dealing with relevant problems.  相似文献   
183.
The dynamics controlling the response of the Baltic Sea to changed atmospheric and hydrologic forcing are reviewed and demonstrated using simple models. The response time for salt is 30 times longer than for heat in the Baltic Sea. In the course of a year, the Baltic Sea renews most of its heat but only about 3% of its salt. On the seasonal scale, surface temperature and ice-coverage are controlled by the atmospheric conditions over the Baltic Sea as demonstrated by e.g. the strong inter-annual variations in winter temperature and ice-coverage due to variations in dominating wind directions causing alternating mild and cold winters. The response of surface temperature and ice-coverage in the Baltic Sea to modest climate change may therefore be predicted using existing statistics. Due to the long response time in combination with complicated dynamics, the response of the salinity of the Baltic Sea cannot be predicted using existing statistics but has to be computed from mechanistic models. Salinity changes primarily through changes in the two major forcing factors: the supply of freshwater and the low-frequency sea level fluctuations in the Kattegat. The sensitivity of Baltic Sea salinity to changed freshwater supply is investigated using a simple mechanistic steady-state model that includes baroclinic geostrophic outflow from the Kattegat, the major dynamical factor controlling the freshwater content in the Kattegat and thereby the salinity of water flowing into the Baltic Sea. The computed sensitivity of Baltic Sea surface salinity to changes of freshwater supply is similar to earlier published estimates from time-dependent dynamical models with higher resolution. According to the model, the Baltic Sea would become fresh at a mean freshwater supply of about 60 000 m3 s−1, i.e. a 300% increase of the contemporary supply. If the freshwater supply in the different basins increased in proportion to the present-day supply, the Bothnian Bay would become fresh already at a freshwater supply of about 37 000 m3 s−1 and the Bothnian Sea at a supply of about 45 000 m3 s−1. The assumption of baroclinic geostrophic outflow from the Kattegat, crucial for the salinity response of the Baltic Sea to changed freshwater supply, is validated using daily salinity profiles for the period 1931–1977 from lightship Läsö Nord.  相似文献   
184.
Cytochrome P450 monooxygenase activities, reflecting the expression of various subfamilies of P450, were measured in liver samples of harp and hooded seal. Differences in some of the investigated parameters were observed between the two species, between sexes, and between pups and adults. Treatment of single female pups from each species with phenobarbital (i.v. 45 mg/kg), resulted in increased levels of EROD and estradiol 2-hydroxylase activities in both species, whereas MCOD, ECOD and PROD activities were induced only in the harp seal sample. Antibodies against a dog P450 2B form (anti-dog PBD-2 IgG) gave a single band around 52kD in both species, strongest in male pups. This band seemed elevated in the PB-treated harp seal pup. Based on the single treated pup of each species, the results suggest that seals respond to PB-type treatment with a weaker response, and with different enzyme patterns, that most terrestrial mammals. Antibodies against cod P450 IAI cross-reacted with two bands in liver samples from adult seals of both species (about 54 and 52kD), but this was strongest in the hooded seal. The intensity of the bands reflected the EROD activities in the samples, suggesting the application of immunodetection in screening marine mammals for effects of environmental contamination.  相似文献   
185.
Managing authorities in Scandinavia arrange public information meetings when members of the public express fear because wolves or brown bears approach human settlements. This study aimed to increase the understanding of the potential effect of information meetings on self-reported fear of wolves and brown bears. In total, 198 participants completed questionnaires before and after the information meetings. Nine follow-up interviews were held 1 year later. The quantitative analyses revealed that participants who found the information credible reported a significant increase in social trust and a decrease in vulnerability and fear. The qualitative analyses pointed to the importance of information content and meta-communication, for example, nonverbal cues. It is proposed that, among participants who find the information credible, information meetings may change the appraisal of wolves and brown bears, and therefore they might prove useful as an intervention to address fear of these animals.  相似文献   
186.

Reports

17th International Cartographic Conference 10th General Assembly of ICA  相似文献   
187.
Summary A new method is described for deriving values of the natural illumination of direct solar radiation from measurements of the latter, integrally with regard to wavelength and, simultaneously, in well-defined spectral regions. The basic equations are presented and graphical comparisons between data so computed and observed analyzed. The degree of prediction of individual short-period values of direct illumination flux (e. g. half-hourly intervals), established for wide ranges of solar height and turbidity, is of the same order as the accuracy generally expected in such series of carefully conducted measurement programs. This technique of employing radiometric rather than photometric measurements is thus shown to have a general application.
Zusammenfassung Es wird eine neue Methode zur Berechnung von Werten der natürlichen Beleuchtungsst?rke durch die direkte Sonnenstrahlung aus Messungen der letzteren abgeleitet, und zwar gleichzeitig für das gesamte Spektrum und für genau abgegrenzte Spektralbereiche. Es werden die Grundgleichungen angegeben und graphische Vergleiche zwischen den so berechneten und den beobachteten Werten durchgeführt. Einzelwerte des direkten Lichtstromes über kurze Zeiten (z. B. Halbstundenintervalle), die für gro?e Bereiche von Sonnenh?he und Trübung berechnet wurden, haben denselben Genauigkeitsgrad, wie man ihn bei sorgf?ltig ausgeführten Me?programmen gew?hnlich erwartet. Damit ist erwiesen, da? die Methode, Strahlungsmessungen statt Lichtmessungen zu verwenden, allgemein angewendet werden kann.

Résumé Les auteurs exposent ici une nouvelle méthode permettant de calculer l'intensité lumineuse naturelle du rayonnement solaire direct au moyen de la mesure de ce dernier. Cette méthode permet le calcul aussi bien pour la totalité du spectre que pour certaines bandes délimitées. Les auteurs indiquent les équations de base et donnent des comparaisons graphiques entre des valeurs observeés et calculées de cette manière. Les valeurs isolées du flux lumineux direct regu en des laps de temps brefs (par exemple dúne demie-heure), valeurs calculées pour de grands intervalles aussi bien de la hauteur du soleil que du trouble atmosphérique, donnent le même degré déxactitude que celui quón peut attendre de mesures directés effectées soigneusement. On a ainsi démontré que la méthode qui consiste à utiliser des mesures du rayonnement au lieu de la luminosité peut être utilisée de fa?on trés g&&ale.


With 3 Figures

Dedicated to Dr.W. M?rikofer on the occasion of his 70th birthday.  相似文献   
188.
This article documents a 240,000-m3 debris flow resulting from a glacial lake outburst flood in Fjærland, Western Norway, May 8, 2004. The event started when a glacial lake breached a moraine ridge. The ensuing debris flow was able to erode material along its path, increasing in volume from about 25,000 to 240,000 m3 before depositing about 3 km from its starting point. Field investigations, pre- and post-flow aerial photographs as well as airborne laser scanning (LIDAR) were used to describe and investigate the flow. The most striking and unusual feature of this case study is the very pronounced erosion and bulking. We have made a detailed study of this aspect. Erosion and entrainment is quantified and the final volume of the debris flow is determined. We also present geometrical and sedimentological features of the final deposit. Based on the Fjærland data, we suggest that a self-sustaining mechanism might partly explain the extreme growth of debris flows traversing soft terrain.  相似文献   
189.
Our aim was to quantify the effects of forest plantation and management (clear cut or 30% partial harvest) in relation to pasture, on catchment discharge in southeast Rio Grande do Sul state, Brazil. A paired‐catchment approach was implemented in two regions (Eldorado do Sul and São Gabriel municipalities) where discharge was measured for 4 years at three catchments in each region, two of which were predominantly eucalypt plantation (mainly Eucalyptus saligna, rotation of approximately 7–9 years) with native forest and grass in streamside zones. The third catchment was covered with grazed pasture. Weather, soils, canopy interception, groundwater level, tree growth, and leaf area index were also measured. The 3‐PG process‐based forest productivity model was adapted to predict spatial daily plantation and pasture water balance including precipitation interception, soil evaporation, transpiration, soil moisture, drainage, discharge, and monthly plantation growth. The TOPMODEL framework was used to simulate water pools and fluxes in the catchments. Discharge was higher under pasture than pre‐harvesting plantation and increased for 1–2 years after complete plantation harvest; this change was less pronounced in the catchments under partial harvest. The ratio of discharge to precipitation before harvesting varied from 7% to 13% in the eucalypt catchments and 28% to 29% under pasture. The ratio increases to 23–24% after total harvest, and to 17% after partial harvesting. The ratio under pasture also increases during this period (to 32–44%) owing to increased precipitation. The baseflow, in relation to total discharge, varied from 28% to 62% under Eucalyptus and from 38% to 43% in the pasture catchments. Hence, eucalypt plantations in these regions can be expected to influence discharge regimes when compared with pasture land use, and modelling suggests that partial harvesting would moderate the magnitude of discharge variation compared with a full catchment plantation harvesting. The model efficiency coefficient (Nash–Sutcliffe model efficiency coefficient) varied from 0.665 to 0.799 for the total period of the study. Simulation of alternative harvesting scenarios suggested that at least 20% of the catchment planted area must be harvested to increase discharge. This model could be a useful practical tool in various plantation forestry contexts around the world. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
190.
Evidence of a dynamic Holocene glacial history is preserved in the terrestrial and marine archives of St. Jonsfjorden, a small fjord‐system on the west coast of Spitsbergen, Svalbard. High‐resolution, remotely sensed imagery from marine and terrestrial environments was used to construct geomorphological maps that highlight an intricate glacial history of the entire fjord‐system. The geomorphology and stratigraphy indicate an early Holocene local glacier advance constrained to the Lateglacial–early Holocene transition. Identification and 14C dating of the thermophilous bivalve mollusc Modiolus modiolus to 10.0±0.12 cal. ka BP suggest a rapid northward migration of the species shortly after deglaciation. Further evidence enhances the understanding of the onset and subsequent climax of the Neoglacial‐Little Ice Age in inner St. Jonsfjorden. The present‐day terminus of Osbornebreen, the dominating glacier system in St. Jonsfjorden, is located over 8.5 km up‐fjord from its Neoglacial maximum extent. Cross‐cutting relationships suggest subsequent advances of all the smaller glaciers in the area following the break‐up of Osbornebreen. Glacial deposits, landforms and their cross‐cutting relationships observed in both terrestrial and marine settings imply a complex and highly dynamic environment through the later part of the Holocene.  相似文献   
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