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排序方式: 共有298条查询结果,搜索用时 15 毫秒
291.
Jana Kierdorf Laura Verena Junker-Frohn Mike Delaney Mariele Donoso Olave Andreas Burkart Hannah Jaenicke Onno Muller Uwe Rascher Ribana Roscher 《野外机器人技术杂志》2023,40(2):173-192
In this paper, we present GrowliFlower, a georeferenced, image-based unmanned aerial vehicle time-series dataset of two monitored cauliflower fields (0.39 and 0.60 ha) acquired in 2 years, 2020 and 2021. The proposed dataset contains RGB and multispectral orthophotos with coordinates of approximately 14,000 individual cauliflower plants. The coordinates enable the extraction of complete and incomplete time-series of image patches showing individual plants. The dataset contains the collected phenotypic traits of 740 plants, including the developmental stage and plant and cauliflower size. The harvestable product is completely covered by leaves, thus, plant IDs and coordinates are provided to extract image pairs of plants pre- and post-defoliation. In addition, to facilitate classification, detection, segmentation, instance segmentation, and other similar computer vision tasks, the proposed dataset contains pixel-accurate leaf and plant instance segmentations, as well as stem annotations. The proposed dataset was created to facilitate the development and evaluation of various machine-learning approaches. It focuses on the analysis of growth and development of cauliflower and the derivation of phenotypic traits to advance automation in agriculture. Two baseline results of instance segmentation tasks at the plant and leaf level based on labeled instance segmentation data are presented. The complete GrowliFlower dataset is publicly available ( http://rs.ipb.uni-bonn.de/data/growliflower/ ). 相似文献
292.
Ni- to Kr-like Pt ions have been studied by relativistic multi-reference Møller–Plesset many-body perturbation theory calculations. Energy levels and lifetimes of low-lying excited states within the n=4 complex are reported for each ion. Wavelengths and transition probabilities for the strongest electric-dipole transitions are compared with available experimental data. Synthetic radiative spectra are shown for various wavelength regions. 相似文献
293.
Hongbin Zhang Gerd Mrozynski Amir Wallrabenstein Juergen Schrage Elmar Griese 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(3):377-389
A self-consistent model of vertical-cavity surface-emitting lasers (VCSEL's) is presented in this paper, in which the carrier diffusion rate equation, the photon density rate equation, and the thermal conduction equation are considered simultaneously. The nonuniform heat flux density distribution in the active region due to the current-spreading effect is taken into account. The effects of temperature on gain and transparency carrier density are also included in this model. It is nonlinearly and self-consistently solved in the Matlab environment. The transient and lateral distribution characteristics of the carrier and photon densities and the junction temperature are investigated. Some interesting results are gotten and analyzed. 相似文献
294.
295.
296.
Klement Möhler und Elmar Hallermayer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1974,156(4):206-210
Zusammenfassung Photometrische Methoden allein reichen als Test für Modellversuche über Bildung und Abbau von cancerogenen Nitrosaminenin vitro und in Lebensmitteln nicht aus. In der Regel ist eine gaschromatographische Trennung die Methode der Wahl. Die mikrobiologisch/enzymatisch katalysierte Nitrosaminbildung verdient besondere Beachtung.
Auszug aus der Dissertation von Elmar Hallermayer: Nitrosamine in Lebensmitteln, Beiträge zu Analytik, Abbau und Aufbau. Technische Universität München 1973 (Promotionstag 29. März 1973).
Der Deutschen Forschungsgemeinschaft danken wir für die finanzielle Unterstützung. 相似文献
Nitrosamines in foods. Contributions to analysis, decomposition and formation I. Determination methods for model experiments
Summary Photometric methods are not sufficient for the investigation of model tests regarding the formation or breakdown of carcinogenic nitrosaminesin vitro or in foods. Usually a GL-separation is the best method. Formation of nitrosamines, enzymatically catalyzed by microorganisms, deserves special attention.
Auszug aus der Dissertation von Elmar Hallermayer: Nitrosamine in Lebensmitteln, Beiträge zu Analytik, Abbau und Aufbau. Technische Universität München 1973 (Promotionstag 29. März 1973).
Der Deutschen Forschungsgemeinschaft danken wir für die finanzielle Unterstützung. 相似文献
297.
Ionic liquid matrixes (ILM) have been shown to allow very homogeneous sample preparations, facilitating relative quantifications using internal standards in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). In the present work, the ability to perform quantifications of peptides without using internal standards in these matrixes was investigated. Linear correlations between peptide amount and signal intensities could be observed when increased molar matrix-to-analyte ratios were applied. The dynamic range of linearity was approximately 1 order of magnitude. The method was applied successfully to monitor the time-dependent evolution of substrates and products in trypsin-catalyzed digests of single peptides and peptide mixtures. Thus, ionic liquid matrixes allow quantitative MALDI-MS without the need for internal standards, making the method a suitable tool for the fast screening of new enzymes or the search for substrates or inhibitors. 相似文献
298.
Ruprecht Jaenicke 《Journal of aerosol science》1980,11(5-6):577-588
The present day knowledge is summarized and the atmospheric aerosols are given in model size distributions. The optical properties relevant for climatological considerations are given. The most recent data about the stratospheric aerosol are given and the correlation with volcanic activities is discussed. Claimed man-made influences upon the global aerosols are critically discussed. While the influences of the stratospheric aerosol on global temperature seem to be confirmed the influence of the tropospheric aerosol remains speculative. 相似文献