2,557 research outputs found
Soil respiration in cucumber field under crop rotation in solar greenhouse
Crop residues are the primary source of carbon input in the soil carbon pool. Crop rotation can impact the plant biomass returned to the soil, and influence soil respiration. To study the effect of previous crops on soil respiration in cucumber (Cucumis statirus L.) fields in solar greenhouses, soil respiration, plant height, leaf area and yield were measured during the growing season (from the end of Sept to the beginning of Jun the following year) from 2007 to 2010. The cucumber was grown following fallow (CK), kidney bean (KB), cowpea (CP), maize for green manure (MGM), black bean for green manure (BGM), tomato (TM), bok choy (BC). As compared with CK, KB, CP, MGM and BGM may increase soil respiration, while TM and BC may decrease soil respiration at full fruit stage in cucumber fields. Thus attention to the previous crop arrangement is a possible way of mitigating soil respiration in vegetable fields. Plant height, leaf area and yield had similar variation trends under seven previous crop treatments. The ratio of yield to soil respiration revealed that MGM is the crop of choice previous to cucumber when compared with CK, KB, CP, BGM, TM and BC
IrányĂtás mint hajĂłzás – a „governance” Ă©rtelmĂ©rĹ‘l
„A végtelen sajátosságának tűnik, hogy mindenhol és mindenben jelen legyen.” (Aquinói Szt. Tamás: Summa Theologiae
Classification-Aided Robust Multiple Target Tracking Using Neural Enhanced Message Passing
We address the challenge of tracking an unknown number of targets in strong
clutter environments using measurements from a radar sensor. Leveraging the
range-Doppler spectra information, we identify the measurement classes, which
serve as additional information to enhance clutter rejection and data
association, thus bolstering the robustness of target tracking. We first
introduce a novel neural enhanced message passing approach, where the beliefs
obtained by the unified message passing are fed into the neural network as
additional information. The output beliefs are then utilized to refine the
original beliefs. Then, we propose a classification-aided robust multiple
target tracking algorithm, employing the neural enhanced message passing
technique. This algorithm is comprised of three modules: a message-passing
module, a neural network module, and a Dempster-Shafer module. The
message-passing module is used to represent the statistical model by the factor
graph and infers target kinematic states, visibility states, and data
associations based on the spatial measurement information. The neural network
module is employed to extract features from range-Doppler spectra and derive
beliefs on whether a measurement is target-generated or clutter-generated. The
Dempster-Shafer module is used to fuse the beliefs obtained from both the
factor graph and the neural network. As a result, our proposed algorithm adopts
a model-and-data-driven framework, effectively enhancing clutter suppression
and data association, leading to significant improvements in multiple target
tracking performance. We validate the effectiveness of our approach using both
simulated and real data scenarios, demonstrating its capability to handle
challenging tracking scenarios in practical radar applications.Comment: 15 page
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