桅杆

Towards evening the mate and boat-swain begged the master of our ship to let them cut away the foremast, which he was very unwilling to: But the boat-swain protesting to him, that if he did not, the ship would founder, he consented; and when they had cut away the foremast, the main-mast stood so loose, and shook the ship so much, they were obliged to cut her away also, and make a clear deck.

临近傍晚，大副和水手长请求我们的船长让他们砍掉船头第一根桅杆；船长当然是很不愿意干的。但水手长坚持说，如果船长不这样做，船就会被风浪击沉；船长同意了。当他们把这根桅杆砍掉，主桅杆就站立不稳，船也随着剧烈摇晃，他们又只得把主桅杆也砍掉。这样就只剩下一个空荡荡的甲板了。

To remove from a step.the third mast from the bow in a vessel having three or more masts; the after and shorter mast of a yawl, ketch, or dandy.

帆船上从船头算起的第三条桅杆有三根或多根桅杆；快艇、双桅船或双桅帆船上后面的短的桅杆。

Any of various small, swift boats.the third mast from the bow in a vessel having three or more masts; the after and shorter mast of a yawl, ketch, or dandy.

帆船上从船头算起的第三条桅杆有三根或多根桅杆；快艇、双桅船或双桅帆船上后面的短的桅杆。

The third mast from the bow in a vessel having three or more masts; the after and shorter mast of a yawl, ketch, or dandy.

帆船上从船头算起的第三条桅杆有三根或多根桅杆；快艇、双桅船或双桅帆船上后面的短的桅杆。

After they had enjoyed fair winds and weather for a season, they were en－countered many times with cross winds and met with many fierce storms with which the ship was shroudly shaken, and her upper works made very leaky; and one of the main beams in the midships was bowed and cracked, which put them in some fear that the ship could not be able to perform the voyage.

至于那根弯曲的主桅杆，因为船上的乘客们从荷兰带了一个巨大的铁螺钉，所以可以用它把那根桅杆复位，然后身兼木匠的船主保证他可以用一根固定在下层甲板上的柱子撑在它的下面，其他方向也绑好，这根桅杆就可以安全使用了。

Furthermore, the parametric vibration of guyed mast analyses and its control method is proposed. Finally, the wind tunnel experiment of guyed mast was carried out, and the test results were examined. Through the experiment, the dynamic characteristics of guyed mast are well understood, and the proposed method is this paper is verified.

并进一步分析了桅杆结构参数振动的特性及其控制方法，通过对桅杆结构风洞试验的分析，了解了桅杆结构在实际工作状态下的动力特性，并证明目前理论的正确性。

Parameter study of three-way guyed mast structure ;2. Damage detection method for vertical bars of mast structure in time domain;3. According to structural dynamic features of mast structure and the change of dynamic properties after damage modal analysis is applied for damage detection.

研究了桅杆结构的破坏原因和破坏机理，针对桅杆结构本身的结构动力特性和损伤后的动力特性改变，对应用模态分析方法在桅杆结构的损伤诊断的应用问题进行了分析，指出了模态分析的损伤诊断方法在桅杆结构中的应用方向。

The guyed mast structure is made of soft cables and slender mast shaft, which dynamic characteristics are very complicated due to its large displacement and nonlinearity. Because its complicated theory is not fully understood yet, the damage probability is relatively high under normal design, construction and material.

桅杆结构是由纤绳和杆身所组成，其大变形及几何非线性使得其动力特性十分复杂，在正常设计、建造及材料情况下，桅杆破坏发生的比例之高在土木建筑中是罕见的，这主要是因为桅杆结构复杂的工作机理尚未完全被揭示。

The along-wind vibration and across-wind vibration , icing situations of Guyed Mast are also studied, furthermore, the parametric vibration, the phenomenon of jump and chaos of the Guyed Mast are investigated; also, the wind tunnel experiment of Guyed Mast first made in China is finished and the test result, along with measurement of the real structure, are examined, which provide the reasonable theory and reliable experimental data for the revision of the high-rise structure code.

本文系统地研究了桅杆的顺风、横风以及在裹冰下的风效应，并进一步分析了桅杆的参激振动、跳跃及混沌现象等，完成了国内首次桅杆结构的风洞试验，分析了桅杆实测和试验结果，为今后高耸结构规范的修订提供了的合理的理论依据和可靠试验数据。

But because of its big slenderness ratio, smaller rigidity and damping, it is easy to cause a larger vibration in the windload and iceload function and so on, mast structure destruction accidents frequently occurred, has caused engineering and academic circles\\\s concern, this article summarizes the main structure damage diagnosis methods, carrys on preliminary dynamic analysis and the time-frequency distribution analysis with the vibration signal to the mast structure, and proposes the signal processing method is a appropriate method on the diagnosis to the mast damage.

但是，由于桅杆结构长细比很大，刚度、阻尼较小，在风荷载、裹冰荷载等作用下容易产生较大幅度的振动，桅杆结构的破坏事故时有发生，引起了工程界和学术界的重视，本文总结了几种主要的结构损伤诊断方法，并对桅杆结构进行了动力分析和振动信号时频分析，并提出信号处理的时频方法对桅杆损伤进行诊断比较合适的。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。