Regnbueørret (Onchorhynchus mykiss); produksjon og interaksjoner med stedegne arter

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Experiences with coastal and maritime UAS BLOS operation with phased-array antenna digital payload data link

This paper describes recent experiences with operating an unmanned aerial vehicle (UAV) in a coastal and maritime environment beyond line of sight (BLOS) in controlled airspace (class D) where separation from other air traffic is provided by the Air Traffic Control (ATC). The UAV operation followed normal ATC procedures with two-way VHF communication between the UAS Operator and ATC in order to provide separation vertically and horizontally by operation within pre-defined areas according to specific operational procedures made by ATC. Tests were conducted using direct 2.4 GHz radio and GPRS mobile network control links at a distance up to 20 km from the ground control station when operating at 1500 ft altitude. A new low-weight and small size experimental phased-array antenna providing a digital high capacity payload data link was tested and found to give stable real-time HD video at a distance of 50 km under line of sight conditions at 2500 ft altitude

Navigation of UAV using Phased Array Radio

Navigation and communication are two of the major challenges when flying unmanned aerial vehicles (UAVs) beyond visual line of sight (BVLOS), in particular when Global Navigation Satellite Systems (GNSS) are unavailable. The phased array radio system used in this paper aims to solve both communication and navigation with one system. To enable high efficiency data transfer, the radio system uses electronic beamforming to direct the energy from the ground radio towards the UAV, but to be able to do this, the ground radio needs to know the bearing and elevation angles towards the UAV. By measuring the round-trip time to compute the range and observing the direction of the incoming signal to compute the bearing and elevation angles, the phased array radio system is able to find the position of the UAV, relative to the ground radio, in all three dimensions. The phased array system is shown to provide absolute measurements for UAV navigation in radio line of sight, which can be used as a redundant system to GNSS measurements. By merging the radio measurements with barometer altitude data, a mean accuracy of approximately 24 m with a standard deviation of approximately 17 m compared to the real time kinematic (RTK) satellite navigation solution is achieved on a UAV flight at a distance of approximately 5 km

Coordinated maritime missions of unmanned vehicles — Network architecture and performance analysis

Multi-vehicle operations using various types of unmanned vehicles (UVs) can increase efficiency of marine data acquisition, reduce the crew risk and lower mission costs. These types of missions are very complex and often involve systems that are not interoperable. From an operational perspective however, some level of integration is necessary. Typically, a common network system architecture and Situation Awareness (SA) platform are required. The architecture allows operators to transfer data between vehicles and their operators, while the SA platform allows to monitor mission progress and react to changes. This paper presents a network system architecture used during an experiment realized in Spring 2016 in Norway. 8 departments from 5 institutions worked together to combine operation of 4 UVs (aerial, surface, underwater), a support vessel and on-shore team. The description is followed by a backbone network performance analysis. Several cases are presented, with focus on a transmission between manned vessel and Unmanned Surface Vehicle (USV), including direct connection, and data-relay mechanism via Unmanned Aerial Vehicle (UAV)

Coordinated maritime missions of unmanned vehicles - network architecture and performance analysis

Multi-vehicle operations using various types of unmanned vehicles (UVs) can increase efficiency of marine data acquisition, reduce the crew risk and lower mission costs. These types of missions are very complex and often involve systems that are not interoperable. From an operational perspective however, some level of integration is necessary. Typically, a common network system architecture and Situation Awareness (SA) platform are required. The architecture allows operators to transfer data between vehicles and their operators, while the SA platform allows to monitor mission progress and react to changes. This paper presents a network system architecture used during an experiment realized in Spring 2016 in Norway. 8 departments from 5 institutions worked together to combine operation of 4 UVs (aerial, surface, underwater), a support vessel and on-shore team. The description is followed by a backbone network performance analysis. Several cases are presented, with focus on a transmission between manned vessel and Unmanned Surface Vehicle (USV), including direct connection, and data-relay mechanism via Unmanned Aerial Vehicle (UAV)

Regnbueørret (Onchorhynchus mykiss); produksjon og interaksjoner med stedegne arter

Den globale spredningen av regnbueørret (Onchorhynchus mykiss) har ført den inn på listen over de 100 verste invaderende arter i verden, utarbeidet av den internasjonale naturvernorganisasjonen IUCN. Den er også oppført på Fremmedartslista i Artsdatabanken, hvor den kategoriseres som en høyrisiko art. På denne bakgrunnen har Fiskeridirektoratet og Miljødirektoratet bestilt en oppdatert gjennomgang av kunnskapsstatus. Den norske produksjonen har de siste ti årene variert mellom vel 50 000 og nesten 90 000 tonn, mens smoltproduksjonen i samme periode har variert mellom 17 og 22 millioner individ. Hovedmengden produseres i Hordaland, Sogn og Fjordane, Møre og Romsdal og Nordland. Årlig antall rapporterte rømte regnbueørret har variert fra under 10 000 til over 300 000 individ. Rømt regnbueørret kan konkurrere med stedegne arter om næringstilbud i ferskvann, og dessuten grave opp og skade gytegroper for laks (Salmo salar) og ørret (Salmo trutta). Regnbueørret kan også være kilde til overføring av patogener og parasitter som for eksempel Gyrodactylus salaris som er en trussel for Atlantisk laks. Undersøkelser viser at regnbueørret som rømmer fra oppdrettsanlegg kan overleve og tilpasse seg tilgjengelige byttedyr i elv og sjø som andre anadrome fisk beiter på. Eksperimentelle studier har vist at i konkurranse med regnbueørret kan laksen bli fortrengt til marginale habitat og derved få redusert tilvekst. Frem til 1996 var det kjent 6 lokaliteter med selvrekrutterende bestander av regnbueørret i Norge, senere er det registrert 2-3 lokaliteter til med sannsynlig reproduksjon. Nye undersøkelser blant annet med miljø-DNA vil kunne gi et mer fullstendig bilde av forekomster av regnbueørret i norske vassdrag. Årsakene til at regnbueørret i liten grad etablerer naturlig reproduserende bestander i Norge og Europa ellers er ikke kjent. Dersom redusert fitness gjennom lang domestisering er årsak til manglende evne til etablering, vil import av nytt genmateriale fra andre avlslinjer evt også fra villfisk, kunne medføre større risiko for etablering. Dersom naturlig forekommende sykdomsorganismer hos stedegne laks og ørret er årsak, vil det være viktig å opprettholde bestander av de stedegne artene. Det er indikasjoner på at regnbueørret har høyere toleranse enn Atlantisk laks med hensyn på fluktuasjoner og forandringer i miljøet. I såfall vil endret flomregime, temperatur eller andre naturlige eller menneskeskapte forhold kunne forandre konkurranseforholdene mellom lokale arter og regnbueørret, og dermed medføre endret risiko for etablering.publishedVersio