Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span styl...Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span style="font-family:Verdana;"> com</span><span style="font-family:Verdana;">pared to tilt-wings or tilt-rotors in the pre-80’s era. Radio-controlled </span><span style="font-family:Verdana;">aerobatic airplanes have thrust-to-weight ratio of greater than unity and are capable of performing a range of impressive maneuvers including the so-called harrier maneuver. We hereby present a new maneuver known as the retarded harrier </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">that is applicable to un/manned fixed-wing aircraft for achieving VTOL flight with a better forward flight performance than a quadplane in terms of weight, speed and esthetics.</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> An airplane with tandem roto-stabilizers is also presented as an efficient airframe to achieve VTOL via retarded harrier maneuver, and detailed analysis is given for hovering at 45° and 60° and comparison is made against the widely adopted quadplane. This work also includes experimental demonstration of retarded harrier maneuver using a small remotely pilot airplane of wingspan 650 mm.</span></span></span>展开更多
[目的]了解水稻重要害虫白背飞虱成虫长翅型个体和短翅型个体在形态测量学方面的具体差异。[方法]利用Nikon体视显微镜操作系统(nikon digital sight DS-QilMC)对白背飞虱长、短翅型成虫前翅和后翅进行详细观察和测量。[结果]短翅型雌...[目的]了解水稻重要害虫白背飞虱成虫长翅型个体和短翅型个体在形态测量学方面的具体差异。[方法]利用Nikon体视显微镜操作系统(nikon digital sight DS-QilMC)对白背飞虱长、短翅型成虫前翅和后翅进行详细观察和测量。[结果]短翅型雌虫的后翅与前翅的比率为0.29±0.03,与长翅型雌、雄成虫相应的比值(分别为0.83±0.01、0.84±0.02)差异显著;长翅型雌虫前翅与短翅型雌虫前翅的比率为2.11±0.04,后翅的比率为6.21±0.05,两者差异达显著水平。此外,还发现短翅型白背飞虱雌成虫前翅中的横脉至翅尾长度与前翅长度的比值只有0.231+0.024,明显小于白背飞虱长翅型雄成虫和长翅型雌成虫的比值(0.387+0.012、0.388+0.012),差异达显著水平。[结论]短翅型雌成虫的前、后翅并未按同等比例缩小,且短翅型雌成虫前翅中的横脉更靠近翅尾。该研究结果将有助于进一步了解稻飞虱翅二型现象的本质。展开更多
文摘Modern day VTOL fixed-wing aircraft based on quadplane design is relative<span style="font-family:Verdana;">ly simple and reliable due to lack of complex mechanical components</span><span style="font-family:Verdana;"> com</span><span style="font-family:Verdana;">pared to tilt-wings or tilt-rotors in the pre-80’s era. Radio-controlled </span><span style="font-family:Verdana;">aerobatic airplanes have thrust-to-weight ratio of greater than unity and are capable of performing a range of impressive maneuvers including the so-called harrier maneuver. We hereby present a new maneuver known as the retarded harrier </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">that is applicable to un/manned fixed-wing aircraft for achieving VTOL flight with a better forward flight performance than a quadplane in terms of weight, speed and esthetics.</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> An airplane with tandem roto-stabilizers is also presented as an efficient airframe to achieve VTOL via retarded harrier maneuver, and detailed analysis is given for hovering at 45° and 60° and comparison is made against the widely adopted quadplane. This work also includes experimental demonstration of retarded harrier maneuver using a small remotely pilot airplane of wingspan 650 mm.</span></span></span>
文摘[目的]了解水稻重要害虫白背飞虱成虫长翅型个体和短翅型个体在形态测量学方面的具体差异。[方法]利用Nikon体视显微镜操作系统(nikon digital sight DS-QilMC)对白背飞虱长、短翅型成虫前翅和后翅进行详细观察和测量。[结果]短翅型雌虫的后翅与前翅的比率为0.29±0.03,与长翅型雌、雄成虫相应的比值(分别为0.83±0.01、0.84±0.02)差异显著;长翅型雌虫前翅与短翅型雌虫前翅的比率为2.11±0.04,后翅的比率为6.21±0.05,两者差异达显著水平。此外,还发现短翅型白背飞虱雌成虫前翅中的横脉至翅尾长度与前翅长度的比值只有0.231+0.024,明显小于白背飞虱长翅型雄成虫和长翅型雌成虫的比值(0.387+0.012、0.388+0.012),差异达显著水平。[结论]短翅型雌成虫的前、后翅并未按同等比例缩小,且短翅型雌成虫前翅中的横脉更靠近翅尾。该研究结果将有助于进一步了解稻飞虱翅二型现象的本质。
