Development of stable crops cultivars adapted to environmental constraints is very important for food security. Safflower, an oilseed crop which tolerates environmental abiotic stresses, is suitable for marginal lands...Development of stable crops cultivars adapted to environmental constraints is very important for food security. Safflower, an oilseed crop which tolerates environmental abiotic stresses, is suitable for marginal lands relatively dry and deprived from fertilizer inputs or irrigation. A set of Moroccan and introduced cultivars as well as international accessions were conducted at Oujda (Eastern of Morocco) during 2009-2010 for late and conventional sowing under two water regimes, in a field experiment using a completely randomized design, with three replications. The objective was to evaluate the effect of genotype and contrasting environment on safflower behavior and to select genotypes with large adaptation to the contrasted environmental conditions. Morphological, physiological and agronomic traits, as well as the stress susceptibility index (SSI), were recorded in this study. Results showed significant effect of genotype, year (sowing time), water regime and their interaction on most of the studied parameters. Late sowing and drought affected negatively all the parameters except seed oil which lightly increased under drought stress. Number of heads per plant (NHP) had the strongest association with seed yield under both drought and non-drought conditions, and hence could be taken as selection criterion for safflower seed yield improvement. Five accessions showed the highest overall mean seed yield (~ 1,000 kg/ha) and four accessions exhibited the highest overall mean seed oil content (〉 310 g/kg). For late sowing, the accessions P1262421 and PI537604 produced the highest seed yield (〉 800 kg/ha) and the highest seed oil content (〉 290 g/kg). For conventional sowing, the accessions PI250076 and PI250523 were the most performant, with a seed yield 〉 1,300 kg/ha and a seed oil content 〉 330 g/kg. Based on their mean productivity across environments, their SSI and their MDA, P1271073 and P1250076 could be selected and used as promising germplasm in safflower breeding program in Morocco as well as other dry areas throughout the world.展开更多
A high resolution speed and position identification algorithm, suitable for brushless DC drives, is presented in this paper. In particular, the algorithm is proposed for BLDC (brushless DC) machines that are charact...A high resolution speed and position identification algorithm, suitable for brushless DC drives, is presented in this paper. In particular, the algorithm is proposed for BLDC (brushless DC) machines that are characterized by an un-ideal trapezoidal emfs shape. The algorithm, which is developed basing upon the MRAS technique (model reference adaptive system) and the Popov's hyperstability criterion, guarantees the convergence of the estimated rotor speed and position signals to their corresponding actual values. The identification procedure can be performed starting from the knowledge of low resolution rotor position signals, phase currents and the BLDC emfs shape. The identification algorithm is properly tested on a BLDC drive controlled by a predictive algorithm, by performing a simulation study in the Matlab-Simulink environment. The corresponding results have highlighted the effectiveness of the proposed sensorless predictive control system, at both low and high speed operation.展开更多
Global climate change poses a severe threat to mountain biodiversity.Phenotypic plasticity and local adaptation are two common strategies for alpine plant to cope with such change.They may facilitate organismal adapta...Global climate change poses a severe threat to mountain biodiversity.Phenotypic plasticity and local adaptation are two common strategies for alpine plant to cope with such change.They may facilitate organismal adaptation to contrasting environments,depending on the influences of the environment or genotype or their interacted effects.In this study,we use an endemic alpine plant(Rorippa elata)in the Hengduan mountains(HDM)to unravel its phenotypic basis of adaptation strategy and evaluate the relative contributions of environment and genotype to its phenotype.We transplanted 37 genotypes of R.elata into two common gardens across low and high elevations(2800 vs.3800 m)during 2021-2022.Nine fitness-related traits were measured,including flowering probability and glucosinolates(GS)content.We estimated the environmental or genotypic contributions to the phenotype and identified the main environmental components.Our results revealed that both environment and genotype-by-environment interactions contributed to the phenotypes of R.elata.Latitudinal heterogeneity was identified as a key factor that explained 24%of the total phenotypic variation.In particular,genotypes of the northern HDM showed significantly higher plasticity in flowering probability than those of the southern HDM.Furthermore,within the southern HDM,GS content indicated local adaptation to herbivory stresses for R.elata genotypes along elevations.In conclusion,our results suggest that R.elata may have adapted to the alpine environment through species-level plasticity or regional-level local adaptation.These processes were shaped by either complex topography or interactions between genotype and mountain environments.Our study provides empirical evidence on the adaptation of alpine plants.展开更多
Due to the good balance between high efficiency and accuracy, meta-model based optimization algorithm is an important global optimization category and has been widely applied. To better solve the highly nonlinear and ...Due to the good balance between high efficiency and accuracy, meta-model based optimization algorithm is an important global optimization category and has been widely applied. To better solve the highly nonlinear and computation intensive en- gineering optimization problems, an enhanced hybrid and adaptive meta-model based global optimization (E-HAM) is first proposed in this work. Important region update method (IRU) and different sampling size strategies are proposed in the opti- mization method to enhance the performance. By applying self-moving and scaling strategy, the important region will be up- dated adaptively according to the search results to improve the resulting precision and convergence rate. Rough sampling strategy and intensive sampling strategy are applied at different stages of the optimization to improve the search efficiently and avoid results prematurely gathering in a small design space. The effectiveness of the new optimization algorithm is verified by comparing to six optimization methods with different variables bench mark optimization problems. The E-HAM optimization method is then applied to optimize the design parameters of the practical negative Poisson's ratio (NPR) crash box in this work. The results indicate that the proposed E-HAM has high accuracy and efficiency in optimizing the computation intensive prob- lems and can be widely used in engineering industry.展开更多
文摘Development of stable crops cultivars adapted to environmental constraints is very important for food security. Safflower, an oilseed crop which tolerates environmental abiotic stresses, is suitable for marginal lands relatively dry and deprived from fertilizer inputs or irrigation. A set of Moroccan and introduced cultivars as well as international accessions were conducted at Oujda (Eastern of Morocco) during 2009-2010 for late and conventional sowing under two water regimes, in a field experiment using a completely randomized design, with three replications. The objective was to evaluate the effect of genotype and contrasting environment on safflower behavior and to select genotypes with large adaptation to the contrasted environmental conditions. Morphological, physiological and agronomic traits, as well as the stress susceptibility index (SSI), were recorded in this study. Results showed significant effect of genotype, year (sowing time), water regime and their interaction on most of the studied parameters. Late sowing and drought affected negatively all the parameters except seed oil which lightly increased under drought stress. Number of heads per plant (NHP) had the strongest association with seed yield under both drought and non-drought conditions, and hence could be taken as selection criterion for safflower seed yield improvement. Five accessions showed the highest overall mean seed yield (~ 1,000 kg/ha) and four accessions exhibited the highest overall mean seed oil content (〉 310 g/kg). For late sowing, the accessions P1262421 and PI537604 produced the highest seed yield (〉 800 kg/ha) and the highest seed oil content (〉 290 g/kg). For conventional sowing, the accessions PI250076 and PI250523 were the most performant, with a seed yield 〉 1,300 kg/ha and a seed oil content 〉 330 g/kg. Based on their mean productivity across environments, their SSI and their MDA, P1271073 and P1250076 could be selected and used as promising germplasm in safflower breeding program in Morocco as well as other dry areas throughout the world.
文摘A high resolution speed and position identification algorithm, suitable for brushless DC drives, is presented in this paper. In particular, the algorithm is proposed for BLDC (brushless DC) machines that are characterized by an un-ideal trapezoidal emfs shape. The algorithm, which is developed basing upon the MRAS technique (model reference adaptive system) and the Popov's hyperstability criterion, guarantees the convergence of the estimated rotor speed and position signals to their corresponding actual values. The identification procedure can be performed starting from the knowledge of low resolution rotor position signals, phase currents and the BLDC emfs shape. The identification algorithm is properly tested on a BLDC drive controlled by a predictive algorithm, by performing a simulation study in the Matlab-Simulink environment. The corresponding results have highlighted the effectiveness of the proposed sensorless predictive control system, at both low and high speed operation.
基金supported by the National Natural Science Foundation of China(32170224,32225005)the NSFC-ERC International Cooperation and Exchange Programs(32311530331)the Youth Innovation Promotion Association CAS(2020391).
文摘Global climate change poses a severe threat to mountain biodiversity.Phenotypic plasticity and local adaptation are two common strategies for alpine plant to cope with such change.They may facilitate organismal adaptation to contrasting environments,depending on the influences of the environment or genotype or their interacted effects.In this study,we use an endemic alpine plant(Rorippa elata)in the Hengduan mountains(HDM)to unravel its phenotypic basis of adaptation strategy and evaluate the relative contributions of environment and genotype to its phenotype.We transplanted 37 genotypes of R.elata into two common gardens across low and high elevations(2800 vs.3800 m)during 2021-2022.Nine fitness-related traits were measured,including flowering probability and glucosinolates(GS)content.We estimated the environmental or genotypic contributions to the phenotype and identified the main environmental components.Our results revealed that both environment and genotype-by-environment interactions contributed to the phenotypes of R.elata.Latitudinal heterogeneity was identified as a key factor that explained 24%of the total phenotypic variation.In particular,genotypes of the northern HDM showed significantly higher plasticity in flowering probability than those of the southern HDM.Furthermore,within the southern HDM,GS content indicated local adaptation to herbivory stresses for R.elata genotypes along elevations.In conclusion,our results suggest that R.elata may have adapted to the alpine environment through species-level plasticity or regional-level local adaptation.These processes were shaped by either complex topography or interactions between genotype and mountain environments.Our study provides empirical evidence on the adaptation of alpine plants.
基金supported by the Research Project of State Key Laboratory of Mechanical System and Vibration(Grant Nos.MSV201507&MSV201606)the National Natural Science Foundation of China(Grant No.51375007)+3 种基金the Natural Science Foundation of Jiangsu Province(Grant No.SBK2015022352)the Fundamental Research Funds for the Central Universities(Grant No.NE2016002)the Open Fund Program of the State Key Laboratory of Vehicle Lightweight Design,P.R.China(Grant No.20130303)the Visiting Scholar Foundation of the State Key Lab of Mechanical Transmission in Chongqing University(Grant Nos.SKLMT-KFKT-2014010&SKLMT-KFKT-201507)
文摘Due to the good balance between high efficiency and accuracy, meta-model based optimization algorithm is an important global optimization category and has been widely applied. To better solve the highly nonlinear and computation intensive en- gineering optimization problems, an enhanced hybrid and adaptive meta-model based global optimization (E-HAM) is first proposed in this work. Important region update method (IRU) and different sampling size strategies are proposed in the opti- mization method to enhance the performance. By applying self-moving and scaling strategy, the important region will be up- dated adaptively according to the search results to improve the resulting precision and convergence rate. Rough sampling strategy and intensive sampling strategy are applied at different stages of the optimization to improve the search efficiently and avoid results prematurely gathering in a small design space. The effectiveness of the new optimization algorithm is verified by comparing to six optimization methods with different variables bench mark optimization problems. The E-HAM optimization method is then applied to optimize the design parameters of the practical negative Poisson's ratio (NPR) crash box in this work. The results indicate that the proposed E-HAM has high accuracy and efficiency in optimizing the computation intensive prob- lems and can be widely used in engineering industry.