Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2017
Forfattere
Ricardo Fonseca Werner Creixell Javier Maiguashca Victor Rueda-AyalaSammendrag
Image analysis is essential through a wide range of scientific areas and most of them have one task in common, i.e. object detection. Thus automated detection algorithms had generated a lot of interest. This proposal identifies objects with similar features on a frame. The inputs are the image where to look at, and a single appearance of the object we are looking for. The object is searched by a sliding window of various sizes. A positive detection is given by a cascaded classifier that compares input patches from sliding window to the object model. The cascaded classifier has three stages: variance comparison, layers of pixel comparisons and patch correlation. Object model is a collection of templates which are generated from scales and rotations of the first appearance. This algorithm is capable to handle change in scale, in plane rotation, illumination, partial occlusion and background clutter. The proposed framework was tested on high cluttered background aerial image, for identifying palm oil trees. Promising results were achieved, suggesting this is a powerful tool for remote sensing image analysis and has potential applications for a wide range of sciences which require image analysis.
Forfattere
Arne SteffenremSammendrag
No abstract has been registered
Sammendrag
The absorption of anthropogenic CO 2 by the oceans is causing a reduction in the pH of the surface waters termed ocean acidification (OA). This could have substantial effects on marine coastal environments where fleshy (non-calcareous) macroalgae are dominant primary producers and ecosystem engineers. Few OA studies have focused on the early life stages of large macroalgae such as kelps. This study evaluated the effects of seawater pH on the ontogenic development of meiospores of the native kelp Macrocystis pyrifera and the invasive kelp Undaria pinnatifi da , in south-eastern New Zealand. Meiospores of both kelps were released into four seawater pH treatments (pH T 7.20, extreme OA predicted for 2300; pH T 7.65, OA predicted for 2100; pH T 8.01, ambient pH; and pH T 8.40, pre-industrial pH) and cultured for 15 d. Meiospore germination, germling growth rate, and gametophyte size and sex ratio were monitored and measured. Exposure to reduced pH T (7.20 and 7.65) had pos itive effects on germling growth rate and gametophyte size in both M. pyrifera and U. pinnatifida , whereas, higher pH T (8.01 and 8.40) reduced the gametophyte size in both kelps. Sex ratio of gametophytes of both kelps was biased toward females under all pH T treatm ents, except for U. pinnatifida at pH T 7.65. Germling growth rate under OA was significantly higher in M. pyrifera compared to U. pinnatifida but gametophyte development was equal for both kelps under all seawater pH T treatments, indicating that the microscopic stages of the native M. pyrifera and the invasive U. pinnatifida will respond similarly to OA.
Sammendrag
No abstract has been registered
Forfattere
Callum Aidan Stephen Hill Greeley BeckSammendrag
This paper discusses the applicability of the Flory–Huggins and Vrentas sorption models for studying the sorption behaviour of wood. This theory was originally developed to explain the sorption behaviour of glassy polymers and was further extended to account for hysteresis effects. The model also has the advantage that, in principle, it does not require adjustable parameters for fitting and can be calculated independently of the sorption isotherm data. It was tested against some sorption isotherms and satisfactory fits to the data were obtained for both the absorption and desorption data. The values of the parameters required for satisfactory fitting were realistic, except for the magnitude of the glass transition temperature of water. As far as the authors are aware, this is the first reported study of the use of the Vrentas model to explain sorption and hysteresis in wood.
Forfattere
Laura Jaakola Laura Zoratti Nga Nguyenquynh Lara Giongo Katja Karppinen Anne Linn Hykkerud Eivind Uleberg Inger Martinussen Hely HäggmanSammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Forfattere
Bjørg Helen Nøstvold Ingrid Kvalvik Rune Rødbotten Eivind Uleberg Sigridur DalmansdottirSammendrag
No abstract has been registered
Forfattere
Mette Thomsen Erlend Indergård Belachew Asalf Tadesse Pia Heltoft Thomsen Anne-Berit Wold Berit Nordskog Gerd Guren Johannes Dyste Hanne LarsenSammendrag
Optimization of produce quality and storage conditions to reduce loss during long-term storage of root vegetables in Norway (OPTIROOT, 2016-2019) Authors: Thomsen, M.G., Indergaard, E., Asalf, B., Heltoft, P., Wold, A.B., Nordskog, B., Guren, G, Dyste, J. & Larsen, H. Author’s affiliation: Key words: carrot, swede, celeriac, storage technology, diseases, physiological disorder, packaging, nutrition Reducing yield loss along the supply chains is important for resource sustainability in vegetable production. Norwegian root vegetables are typically stored 6 to 8 months before consumption, often resulting in 20-30% loss post harvest. In OptiRoot 26 producers, refrigeration-technology companies, sensor developer, grower’s organisation, agricultural advisory service, and four research institutes are cooperating and conducting research to improve storage quality of carrot, swede and celeriac. The research focuses on: i) Fertilizer/Boron deficiency affects the storage quality of root vegetables and amount, methods of application, and timing of boron are studied in swede and celeriac. ii) Interaction between storage conditions/functions and produce quality of the root vegetables through mapping of technical features of 27 storages. The storage conditions recorded are relative humidity, air movement, temperature in boxes and storages, and physical features of storages. In addition, the physiological and health status of the produces are assessed one week before harvest, postharvest and post-storage. The prevalence of fungal diseases or disorders varied from region to region and between storages. iii) Effects of pre-storage wound healing are tested using seven different temperature strategies (direct to 0° C vs. down 0.2° C per day vs. 1° C per day) and low/high humidity in carrot (2016/17/18), celeriac and swede (2017/18/19). Preliminary results show that wound healing reduced loss due to fungal infections in carrot iv) CO2 concentration, temperature and relative humidity were recorded over time inside carrot storage bin liners with different numbers of perforations. An initial screening indicated a positive correlation between number of holes and number of fresh roots. As a post storage method, coating of swede with chitosan oligomers will be tested to inhibit growth of post-harvest pathogens. In conclusion, OptiRoot have gained good progress and promising preliminary results by connecting data on biology and technology for reduction of loss during long-term storage.