查询词典 dorsal fin

Pectoral fin long, far more than the end of the ventral fin base.

胸鳍长，末端远超过腹鳍基部。

The experimental results prove that an IPMC based centimeter scale micro robot fish is feasible. The velocity control can be realized by changing frequency and duty ratio of the control signal, and ascent-descent, turning, cruising can be realized by the cooperation of pectoral fin and caudal fin.

实验结果证明，基于IPMC的厘米级机器鱼是可行的：通过改变控制信号的频率和占空比，实现微型机器鱼的速度控制；通过控制胸鳍和尾鳍，实现上浮、下潜、转弯、巡游等运动模式。

Any of several rays of the family Mobulidae,inhabiting tropical and subtropical seas and having a large flattened body,winglike pectoral fin s,a whiplike tail,and two hornlike fin s that project forward from the head.

蝠鲼任一种蝠鲼科的鳐鱼，生活在热带或副热带海域，有大而扁平的身体和翼状的胸鳍，以及鞭状的尾，头的前部有两个角状的向前突出的鳍

His paper established the physics model for the newly developed under water bio-robot Robo-Mackerel moving about under the pattern of the swinging of its pectoral fin, and the motion equation of the swinging of mechanical pectoral fin was presented.

对新近研制的仿生水下机器人Robo-Mackerel，建立其在胸鳍摆动模式下游动的物理模型，并给出机械胸鳍摆动的运动方程。

Two-winged species have only the pectoral fin s enlarged; four-winged species have both the pectoral and the pelvic fin s enlarged.

有些种类具双翼而仅胸鳍较大，有些则有四翼，胸、腹鳍皆大。

The research achievement provides valuable theory and advanced engineering method for engineering design, manufacture, improve and accident analysis of fin-stabilited sabot-discarded penetrator, and it has higher practical value to improve quality and efficiency of design, and reduce design cost for fin-stabilited sabot-discarded penetrator.

本文研究成果能为尾翼稳定脱壳穿甲弹的设计分析、研制、改型和事故分析提供参考，这种计算分析方法对提高脱壳穿甲弹的设计质量和效率，降低设计成本，有较大的实用价值。

In order to improve the maneuverability of underwater biomimetic fish-like propulsor, we recently study black ghost knifefish which typically uses undulatory locomotion of ventral ribbon fin to produce thrust. The morphology and kinematics of this ribbon fin is analyzed.

为了提高仿鱼型推进器在水中运动的灵活性，选择了典型的依靠腹部绸带状鱼鳍波动运动产生推进力的黑色魔鬼刀鱼进行研究，对此绸带状鱼鳍的形态和运动机理进行了分析，同时对鱼鳍的结构进行简化。

Firstly, this dissertation carries out bionic research on the motion of fish body and caudal fin of Thunmiform swimmers in one-dimensional steady swimming for the purpose of establishing kinematic model of underwater propulsor of Thunmiform. This paper also presents the kinematic parameters which describe the motion of fish body and caudal fin, the fundamental approach to getting the propulsion force and the factors related to the propulsion force and efficiency.

首先，从建立仿鲹科加新月形尾鳍推进模式水下推进器运动学模型的目的出发，对采用鲹科加新月形尾鳍推进模式的鱼类在一维稳态游动情况下的身体以及尾鳍的运动进行了仿生学研究，研究了推进运动的基本特征，给出了身体及尾鳍的运动状态、描述其运动的运动学参数、推进力产生的基本途径以及与推进力和推进效率有关的因素，从而为仿鱼水下推进器运动学建模与仿真提供了仿生学基础。

When the saturated vapor of pure R11 or R113 was condensed on the PF tubes under free convection conditions, the HTCs (based on the outside area of the base tube, the same be1ow) were 14 to 20 times those of the smooth tube because the condensate surface tension made the condensate film on fin surfaces thin and the rough saw-toothed fin surfaces disturbed the boundary layer in the condeneate film.

纯R11、R113的饱和蒸气在大空间花瓣形翅片管上冷凝时，由于凝液的表面张力将翅片表面上的液膜拉薄以及粗糙的锯齿形的翅片表面扰乱了凝液膜内的流动边界层，传热膜系数（以坯管外表面积为基准，下同）是光滑管的14—20倍。

Changes in rheological properties and structure of shark fin s(gel strength,maximum breakage strain,shearing strength and fracture stress) were studied on shark fin s heated for various periods(1h,2h,3h,and 4h)by a texture meter.

研究了鱼翅在不同加热时间(1、2、3、4 h)条件下组织构造及其物性学参数(凝胶强度、最大破断应变、剪切应力、破断强度)变化，并测定了胶原蛋白含量。

A carrier gas such as nitrogen is directed through line 20 and valve 22 to connect with line 26 and mix with the gas sample.

如氮气之类的载体通过管线20和阀22引入，与管线26相通，与气体样品混合。

But for the most part, knaves and parasites had the command of his fortune

然而支配他的家产的大多是恶棍和寄生虫。