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| Registros recuperados: 32 | |
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| Satti Hassan Yasir; Department of Agricultural Mechanization, College of Engineering, Huazhong Agricultural University, Wuahn-China; QingXi Liao; Department of Agricultural Mechanization, College of Engineering, Huazhong Agricultural University, Wuahn-China; Jiajia Yu; Department of Agricultural Mechanization, College of Engineering, Huazhong Agricultural University, Wuahn-China; Dali He; Department of Agricultural Mechanization, College of Engineering, Huazhong Agricultural University, Wuahn-China. |
| The objective of this study was to apply the precision metering on wheat seeding to overcome seed damage, seed loss and non-uniform distribution. Accordingly, a prototype of the pneumatic precision metering device for wheat was developed. The performance of the device, including quality of feed index (QFI), multiple index (MULI), miss index (MISI) and seed rate expressed in number of kernels per meter length (KPM), was investigated under laboratory conditions in Wuhan using a test stand with camera system. The results revealed that the rotating speed (RS) and negative pressure (NP) and their interactions had a significant effect on these variables. The maximum QFI (92.98%) was obtained at rotating speed of 19.0 rpm and negative pressures of 2.5 kPa... |
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Palavras-chave: Wheat; Experiments; Performance indices; Pneumatic precision metering device. |
| Ano: 2012 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2073 |
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| Huber, Robert; Swiss Federal Institute for Forest, Snow and Landscape Research WSL; robert.huber@wsl.ch; Rigling, Andreas; Swiss Federal Institute for Forest, Snow and Landscape Research WSL; andreas.rigling@wsl.ch; Bebi, Peter; WSL Institute for Snow and Avalanche Research SLF; bebi@slf.ch; Brand, Fridolin Simon; Natural and Social Science Interface, Department of Environmental Systems Science, ETH Zurich; fridolin.brand@env.ethz.ch; Briner, Simon; Agri-food and Agri-environmental Economics Group, Department of Environmental Systems Science, ETH Zurich; briners@ethz.ch; Hirschi, Christian; Environmental Policy and Economics, Department of Environmental Systems Science, ETH Zurich; christian.hirschi@env.ethz.ch; Lischke, Heike; Swiss Federal Institute for Forest, Snow and Landscape Research WSL;; Scholz, Roland Werner; Natural and Social Science Interface, Department of Environmental Systems Science, ETH Zurich; roland.scholz@env.ethz.ch; Seidl, Roman; Natural and Social Science Interface, Department of Environmental Systems Science, ETH Zurich; roman.seidl@env.ethz.ch; Walz, Ariane; Potsdam Institute for Climate Impact Research PIK; Institute for Earth and Environmental Science, University of Potsdam;; Zimmermann, Willi; Environmental Policy and Economics, Department of Environmental Systems Science, ETH Zurich;; Bugmann, Harald; Forest Ecology, Department of Environmental Systems Science, ETH Zurich; harald.bugmann@env.ethz.ch. |
| Mountain regions provide essential ecosystem goods and services (EGS) for both mountain dwellers and people living outside these areas. Global change endangers the capacity of mountain ecosystems to provide key services. The Mountland project focused on three case study regions in the Swiss Alps and aimed to propose land-use practices and alternative policy solutions to ensure the provision of key EGS under climate and land-use changes. We summarized and synthesized the results of the project and provide insights into the ecological, socioeconomic, and political processes relevant for analyzing global change impacts on a European mountain region. In Mountland, an integrative approach was applied, combining methods from economics and the political and... |
| Tipo: Peer-Reviewed Synthesis |
Palavras-chave: Adaptive management; Climate change; Ecosystem services; Experiments; Interdisciplinary research; Land-use change; Modeling; Transdisciplinary research. |
| Ano: 2013 |
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| Bouvy, Marc; Dupuy, Christine; Got, Patrice; Domaizon, Isabelle; Carré, Claire; Pagano, Marc; Debroas, Didier; Roques, Cécile; Leboulanger, Christophe. |
| Planktonic communities from Juan de Nova lagoon were submitted to a single exposure of diuron or naphthalene in triplicate outdoor 40-L mesocosms for 5 days. The study followed the temporal changes of the assemblages by determining abundances and taxonomic level of microbial (heterotrophic prokaryotes, picocyanobacteria, heterotrophic protists and phytoplankton) and metazooplankton communities. Exposure to both contaminants did not result in significant changes in phytoplankton abundances. Microscopic identification demonstrated the dominance of Bacillariophyta (mostly Chaetoceros tenuissimus) accounting for more than 95% of the microalgae detected in all mesocosms. Using 18S rRNA metabarcoding, temporal changes in the proportion of eukaryotic operational... |
| Tipo: Text |
Palavras-chave: Contaminant; Taxonomy; Metabarcoding; Plankton; Experiments; Lagoon.. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00681/79348/81853.pdf |
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| Morvan, Barthelemy; Bles, G; Dumergue, Nicolas; Priour, Daniel. |
| The evaluation of the mesh opening stiffness of fishing nets is an important issue in assessing the selectivity of trawls. It appeared that a larger bending rigidity of twines decreases the mesh opening and could reduce the escapement of fish. Nevertheless, netting structure is complex. A netting is made up of braided twines made of polyethylene or polyamide. These twines are tied with non-symmetrical knots. Thus, these assemblies develop contact-friction interactions. Moreover, the netting can be subject to large deformation. In this study, we investigate the responses of netting samples to different types of solicitations. Samples are loaded and unloaded with creep and relaxation stages, with different boundary conditions. Then, two models have been... |
| Tipo: Text |
Palavras-chave: Numerical model; Experiments; Braided twine; Mesh opening rigidity; Large deformation.. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00348/45899/45581.pdf |
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| Grasso, Florent; Le Hir, Pierre; Bassoullet, Philippe. |
| Sediment transport modelling in estuarine environments, characterised by cohesive and non-cohesive sediment mixtures, has to consider a time variation of erodibility due to consolidation. Generally, validated by settling column experiments, mud consolidation is now fairly well simulated; however, numerical models still have difficulty to simulate accurately the sedimentation and consolidation of mixed sediments for a wide range of initial conditions. This is partly due to the difficulty to formulate the contribution of sand in the hindered settling regime when segregation does not clearly occur. Based on extensive settling experiments with mud-sand mixtures, the objective of this study was to improve the numerical modelling of mixed-sediment consolidation... |
| Tipo: Text |
Palavras-chave: Mud-sand mixtures; Hindered settling; Consolidation; Experiments; Numerical modelling; Segregation. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00254/36539/35168.pdf |
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| Hudson, Darren. |
| The roots and uses of economic experiments in problem solving and hypothesis testing are explored in the present article. The literature suggests that the primary advantage of economics experiments is the ability to use controlled stimuli to test economic hypotheses. Other literature also suggests that experiments are useful in problem solving settings. The advantages and disadvantages of experiments are discussed. |
| Tipo: Journal Article |
Palavras-chave: Experiments; Problem solving; Hypothesis testing; C81; C91; C92; C93. |
| Ano: 2003 |
URL: http://purl.umn.edu/43209 |
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| Spraggon, John M.. |
| This paper tests the ability of an exogenous targeting instrument to induce compliance when the principal cannot observe the actions of individual agents. A number of papers show that although these instruments are able to induce groups to the target outcome, they are not able to induce individuals to make socially optimal decisions in a number of different controlled laboratory experiments. This study investigates whether the information individuals have about others’ payoffs affects how they make their decisions in this environment. Ledyard (1995) suggests that when subjects have less information in public goods experiments they are more likely to choose the Nash equilibrium decision. However, as he points out, this effect differs between groups with... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Moral Hazard in Groups; Exogenous Targeting Instruments; Experiments; Information; Research Methods/ Statistical Methods; C72; C92; D70. |
| Ano: 2007 |
URL: http://purl.umn.edu/7383 |
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| Spraggon, John M.; Oxoby, Robert J.. |
| We explore the effects of recommended play and the presentation of payoff information on behavior in an ambient-based policy instrument experiment. Specifically, we test the effects of recommended play (via a description of marginal decision making) and a payoff table on the behavior of individuals facing an ambient-based policy instrument. We find that recommended play and the presentation of a payoff table increases the use of the socially optimal strategy, thereby increasing efficiency. These results suggest that providing decision makers with a richer description of the decision making environment significantly reduces decision error, significantly improving the efficiency of ambient-based policy instruments. |
| Tipo: Journal Article |
Palavras-chave: Ambient pollution instruments; Recommended play; Experiments; Environmental Economics and Policy. |
| Ano: 2010 |
URL: http://purl.umn.edu/90832 |
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| Kovarik, Jaromir; Mengel, Friederike; Romero, Jose Gabriel. |
| We study (anti-) coordination problems in networks in a laboratory experiment. Partici- pants interact with their neighbours in a fixed network to play a bilateral (anti-) coordination game. Our main treatment variable is the extent to which players are heterogeneous in the number of connections (neighbors) they have. Other network characteristics are held constant across treatments. We find the following results. Heterogeneity in the number of connections dramatically improves the rate of successful coordination. In addition, even though there is a multiplicity of Nash equilibria theoretically, a very sharp selection is observed empirically: the most connected player can impose her preferred Nash equilibrium almost always and observed Nash equilibria are... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Game Theory; Networks; Coordination Problems; Experiments; Risk and Uncertainty; C72; C90; C91; D85. |
| Ano: 2010 |
URL: http://purl.umn.edu/61370 |
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| Registros recuperados: 32 | |
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