Jens Hansen – författare
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2 produkter
2 produkter
E-bok
Engelska, 2013106 kr
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"Thrilling, dramatic, historic." —Robert K. TanenbaumLife And Death At Parkland HospitalOn November 22, 1963, Dr. Charles Crenshaw, an accomplished surgeon, tried to save John F. Kennedy''s life -- and then days later, the life of the alleged assassin, Lee Harvey Oswald. His gripping, firsthand account contradicts the Warren Commission and years of public misperception to illuminate a chapter in American history long cloaked in conspiracy. Writing with eye-opening immediacy, Dr. Crenshaw takes readers into the emergency room to share the critical events at Parkland Hospital as he lived them. Now updated, his searing testimony punctures myths and shatters a cover-up of massive proportions. "Hard-hitting, courageous, and correct in every respect." —Cyril Wecht, M.D., J.D. "Dr. Crenshaw offers his expert opinion with persuasive evidence. Read this page-turning account of the Kennedy assassination." —Robert K. TanenbaumDeputy Chief Counsel, Congressional Committee Investigation into the Assassination of President KennedyIncludes revealing photosPreviously published as JFK Conspiracy of Silence
E-bok
PDF, Engelska, 202019 kr
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Master's Thesis from the year 2020 in the subject Agrarian Studies, grade: B, University of Copenhagen (Institute of Plant and Environmental Science (PLEN)), language: English, abstract: In this thesis, the Hi-sAFe and yield-safe are calibrated with data from two sets of alley cropping systems, one Danish and one English. Then, predictions of crop yields and tree growth for the growing systems are made with the models and compared to measured data. The quality of the model outputs is evaluated regarding accuracy, correlation to measurements, and bias, and the strengths, weaknesses and potentials of the models are described. Alley cropping is an agroforestry practice with considerable potentials of providing both environmental and economic benefits in Northern Europe. However, these potentials are rarely quantified, and the knowledge required to design new alley cropping systems is lacking. Computer simulation of alley cropping systems may provide solutions through estimation. The objective of this study is to validate the Hi-sAFe and yield-safe models regarding predictions of tree growth and crop yields in Northern European alley cropping systems. Data from the Ministry of Agriculture, Fisheries and Food-sponsored alley cropping systems (MAFF-sponsored trials) and the Combined Food and Energy system, Copenhagen (CFEC) were used. For the MAFF-sponsored trials, data from one (Cirencester trial) out of three sites (Cirencester, Silsoe and Leeds trials) were used for calibration. For the CFEC, data for a subset (years 2012-2019) of the recorded period (2000-2019) was used for calibration. Then, validation simulations were run with the remaining data from each set. For the English growing systems, both models showed substantial error in crop yield predictions (r2 = 0.02-0.57), but successfully simulated tree growth (r2 = 0.94-1.00). In the Danish systems, yield-safe produced better predictions of crop yield (r2 = 0.01-0.35) than Hi-sAFe (r2 = 0.03-0.05), and none of the models reproduced the variability of tree growth measurements (r2 = 0.02-0.09). For all simulations, yield-safe was substantially easier to use, and thus more efficient, than Hi-sAFe, which on the other hand has been used to deliver critical insights in transdisciplinary studies. Suggestions for further model developments are given, and appropriateness of using the models for different tasks is discussed. This may have relevance to researchers of agroforestry modelling and potential model users.