Walters, C. (1995). Estimation of historical stock sizes and recruitment anomalies from relative abundance time series (Vol. 52).
Zusammenfassung: Often only simple relative abundance time series and basic growth and (or) survival estimates are available for assessing impacts of fishing and environmental factors. Assessment then involves fitting production models to the series, while forcing the model with observed catch or effort series. A key uncertainty in this approach is how to deal with recruitment variations due to factors other than stock size. A dynamic programming algorithm can be used to compute maximum likelihood estimates of the recruitment anomaly sequence, given prior knowledge of growth parameters, the natural survival rate, and proportion of the variation in the relative abundance index that is due to abundance measurement errors.
Schlüsselwörter: stock-assessment; approximation-; anomalies-; recruitment-; abundance-; growth-; survival-; algorithms-; fishery-management; marine-fisheries
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Hiramatsu, K., Akamine, T., & Kitada, S. (1995). Effectiveness of partial likelyhood of estimating fish mortality rates from tag recoveries and the stock composition in the mixed population based on genetic data.
Zusammenfassung: Because of the simplicity of calculation and the availability of evaluating the precision of the estimates, a partial likelihood approach has been used for estimating fish mortality rates from tag recoveries and the stock composition in the mixed population based on genetic data. We compare the partial likelihood estimator with the full likelihood estimator, and find that under some conditions, both estimators are the same. The above applications meet the conditions and hence the estimates using the partial likelihood are the same as the ones using the full likelihood. In this case, the partial likelihood approach is quite useful.
Schlüsselwörter: stock-assessment; tagging-; genomes-; fishing-mortality; mixing-ratio; mathematical-analysis
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Gronek, G. (1995). Ähnlichkeiten gesucht – Fehlertoleranter Suchalgorithmus `Shift-AND`.
Schlüsselwörter: suchen, algorithmus, textverarbeitung, theorie, c, listing
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Gronek, G. (1995). Optimal schnell – Schnelle Textsuche mit ´Optimal Mismatch´.
Schlüsselwörter: textverarbeitung, methode, suchen, algorithmus, c, listing, tools
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Strass, H. (1995). Alles an einem Strang – USB: der universelle Bus für Peripherie-Geräte.
Schlüsselwörter: treiber, hardware, schnittstelle, theorie
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Rudolph, R. (1995). Lauflicht am Ende des LAN – UTP Tester (Vol. 1995).
Schlüsselwörter: UTP-Tester, Hardware, Ethernet
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Hüskes, R. (1995). Tool-Almanach – VBX- und OCX-Module im Überblick.
Schlüsselwörter: vbx, vergleich, ocx, delphi, c++, software
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Magnusson, K. G. (1995). An overview of the multispecies VPA -- theory and applications (Vol. 5).
Zusammenfassung: Multispecies virtual population analysis is an attempt to take species interactions into account when assessing the status of fish stocks. It was introduced primarily with the aim of lowering the uncertainty in the natural mortality rate as used in single species VPA and to take account of variability between years and ages by calculating inside the model the part of the mortality rate caused by predation. The output of the MSVPA is therefore – in addition to stock sizes and fishing mortality rates as in single species VPA and intraspecific – and possible species replacement are not considered and neither is predation on larvae and prerecruits. The potential relevance of multispecies models lies in long-term forecasts since short-term forecasts from multi- and single species models differ only slightly. In making long-term forecasts, predicting recruitment is of fundamental importance and the value of MSVPA in throwing light on the processes governing recruitment is limited. MSVPA is concerned primarily with calculating postrecruitment mortalities, and although in principle there is nothing to prevent prerecruitment predation mortalities being calculated, such estimates are not likely to be reliable or useful. Predation on the larval stages can be of major importance in determining recruitment but is not addressed in the MSVPA. Thus, it is quite possible that processes which are not dealt with in the MSVPA are much more important in determining the future of the fisheries. In view of all this uncertainty, it is inevitable that it will be questioned whether multispecies management advice is superior to single species advice.
Schlüsselwörter: vpa, statistik, modell, vergleich, fischerei
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Brunke, M., Schwörbel, J., & Wendling, K. (1995). Die Auswirkungen eines Flußtunnels auf die Fliessgewässerbiozoenose: Makrozoobenthon und Fischfauna (Vol. 24).
Zusammenfassung: Im Stadtgebiet von Idar-Oberstein wurde die Nahe auf einer Laenge von 1880 m durch Ueberbauung und massiven Ausbau der Sohle hermetisch vom Umland abgeschlossen. Zusaetzlich wurde der natuerliche Geschiebebetrieb durch ein Wehr oberhalb des Tunnels unterbrochen. Die Makroinvertebraten- und Fischfauna ist im Tunnel hinsichtlich der Artenzusammensetzung und der Individuendichte verarmt, eine photoautotrophe Besiedlung fehlt. Die Driftdichte ist im Tunnel verringert, die Driftrate erhoeht, der Sauerstofftagesgang stark veraendert. Einfluesse auf die nahen Bereiche ober- und unterhalb des Tunnels liessen sich in dieser Untersuchung nicht feststellen. Hinweise auf oekologische Aspekte bei der Konstruktion aehnlicher Anlagen werden gegeben.
Schlüsselwörter: Wasserbau, Ökologie, Gewässerverbau, Fisch
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Hahn, S. (1995). Untersuchungen zur Besiedelung von Fischteichen mit submersen Makrophyten in der Oberlausitz. Rostock: Universität Rostock.
Schlüsselwörter: Wasserpflanzen, Fischteich
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