To enhance the stability of helicopter maneuvers during task execution,a composite trajectory tracking controller design based on the implicit model(IM)and linear active disturbance rejection control(LADRC)is proposed...To enhance the stability of helicopter maneuvers during task execution,a composite trajectory tracking controller design based on the implicit model(IM)and linear active disturbance rejection control(LADRC)is proposed.Initially,aerodynamic models of the main and tail rotor are created using the blade element theory and the uniform inflow assumption.Subsequently,a comprehensive flight dynamic model of the helicopter is established through fitting aerodynamic force fitting.Subsequently,for precise helicopter maneuvering,including the spiral,spiral up,and Ranversman maneuver,a regular trim is undertaken,followed by minor perturbation linearization at the trim point.Utilizing the linearized model,controllers are created for the IM attitude inner loop and LADRC position outer loop of the helicopter.Ultimately,a comparison is made between the maneuver trajectory tracking results of the IM‑LADRC and the conventional proportional-integral-derivative(PID)control method is performed.Experimental results demonstrate that utilizing the post-trim minor perturbation linearized model in combination with the IM‑LADRC method can achieve higher precision in tracking results,thus enhancing the accuracy of helicopter maneuver execution.展开更多
为探究直接复热、水浴复热、微波复热和汽蒸复热方式对川菜回锅肉风味的影响,该研究以智能感官技术中的电子鼻和电子舌与氨基酸分析仪和顶空气相色谱-离子迁移谱(HS-GC-IMS)相结合,对回锅肉在4种复热方式处理下的风味特征进行了系统分...为探究直接复热、水浴复热、微波复热和汽蒸复热方式对川菜回锅肉风味的影响,该研究以智能感官技术中的电子鼻和电子舌与氨基酸分析仪和顶空气相色谱-离子迁移谱(HS-GC-IMS)相结合,对回锅肉在4种复热方式处理下的风味特征进行了系统分析。结果表明,电子鼻和电子舌能有效识别回锅肉的香气与口感特征;其中微波复热显著提升了回锅肉的营养价值。该研究共检测到17种游离氨基酸,经微波复热处理后的回锅肉总游离氨基酸含量达到最高值(202.08±6.68)mg/g。偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)模型显示直接复热与汽蒸复热之间的风味差异最显著,根据变量重要性投影(variable importance in projection,VIP)值,筛选出22种关键差异香气物质,包括1-戊烯-3-醇、顺-2-戊烯醇等,可作为区分不同复热方式回锅肉香气特征的挥发性标志物。该研究为回锅肉的复热方式提供了重要理论依据,并为进一步探究不同复热方式对回锅肉风味的影响提供了数据支持。展开更多
基金supported in part by the National Natural Science Foundation of China(No.12032012)the Key Discipline Construction Project of Colleges and Universities in Jiangsu Province.
文摘To enhance the stability of helicopter maneuvers during task execution,a composite trajectory tracking controller design based on the implicit model(IM)and linear active disturbance rejection control(LADRC)is proposed.Initially,aerodynamic models of the main and tail rotor are created using the blade element theory and the uniform inflow assumption.Subsequently,a comprehensive flight dynamic model of the helicopter is established through fitting aerodynamic force fitting.Subsequently,for precise helicopter maneuvering,including the spiral,spiral up,and Ranversman maneuver,a regular trim is undertaken,followed by minor perturbation linearization at the trim point.Utilizing the linearized model,controllers are created for the IM attitude inner loop and LADRC position outer loop of the helicopter.Ultimately,a comparison is made between the maneuver trajectory tracking results of the IM‑LADRC and the conventional proportional-integral-derivative(PID)control method is performed.Experimental results demonstrate that utilizing the post-trim minor perturbation linearized model in combination with the IM‑LADRC method can achieve higher precision in tracking results,thus enhancing the accuracy of helicopter maneuver execution.
文摘为探究直接复热、水浴复热、微波复热和汽蒸复热方式对川菜回锅肉风味的影响,该研究以智能感官技术中的电子鼻和电子舌与氨基酸分析仪和顶空气相色谱-离子迁移谱(HS-GC-IMS)相结合,对回锅肉在4种复热方式处理下的风味特征进行了系统分析。结果表明,电子鼻和电子舌能有效识别回锅肉的香气与口感特征;其中微波复热显著提升了回锅肉的营养价值。该研究共检测到17种游离氨基酸,经微波复热处理后的回锅肉总游离氨基酸含量达到最高值(202.08±6.68)mg/g。偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA)模型显示直接复热与汽蒸复热之间的风味差异最显著,根据变量重要性投影(variable importance in projection,VIP)值,筛选出22种关键差异香气物质,包括1-戊烯-3-醇、顺-2-戊烯醇等,可作为区分不同复热方式回锅肉香气特征的挥发性标志物。该研究为回锅肉的复热方式提供了重要理论依据,并为进一步探究不同复热方式对回锅肉风味的影响提供了数据支持。
