In this application, the lorentz force generated by the interaction between the current in the wire and the geomagnetic field produces an electro - dynamic drag leading to a fast orbital decay. in this paper, we make an intensive study of the process of de - orbiting using electro - dynamic tether system. the concrete work includes : firstly, i have studied the basic principle of how to generate the electro - dynamic drag, modeled via accuracy geomagnetism, made a concrete analysis of the de - orbiting duration, the magnitude and direction of electro - dynamic drag under the action of the dipole and accurate geomagnetic models, set up a counterbalance between electro - dynamic torque and gravity gradient torque, emulate the de - orbiting process of spacecraft, and compared the change of six orbital factors and the de - orbiting duration under the action of the dipole and accurate geomagnetic models
本文對基於電動力纜繩的航天器離軌過程進行了深入研究,具體工作如下:首先,本文研究了電動力纜繩產生電動力拉力的基本原理,建立了精確地
磁場模型;分別在偶極子模型和精確地
磁場模型作用下,對電動力拉力的大小、方向、離軌時間及電動力纜繩
傾角的大小進行了計算分析;建立了電動力力矩與纜繩系統重力梯度力矩的平衡關系;分析了電動力力矩為系統提供能量的原理;最後分別在偶極子地
磁場模型和精確地
磁場模型作用下,對受電動力纜繩作用的航天器的離軌過程進行模擬,分析了在不同精度地
磁場模型下,航天器離軌過程中各軌道參數的變化情況,並比較了不同模型對離軌時間的影響。
The main achievements are as follows : the theory models of defect mfl field are set up ; based on the magnetic dipole model and finite element model, the distribution of defect mfl field is simulated in the dissertation ; the component of flux density ( magnetic filed ) parallel to the surface of pipe is detected by a circumferential array of hall probes ; the factors including defect geometry parameters, defect surface angle and shape, pipe material, field intensity, vehicle velocity, background magnetization, operating pressure and remanent magnetization and so on influence the mfl signal characteristics
採用霍爾元件作為缺陷漏
磁檢測傳感器,獲得管道軸截面漏
磁場切向分量的漏
磁信號;研究了缺陷外形尺寸、缺陷
傾角和形狀、管道材質和
磁化強度、檢測儀移動速度、管道背底
磁場、管內壓力和剩
磁對漏
磁信號的影響。提出了各通道增益放大、各路漏
磁信號偏離調整、波形微分、數字濾波和平滑等漏
磁信號預處理方法;分析了等空間采樣的漏
磁信號轉換為等時間采樣信號的必要性,研究了漏
磁信號的小波去噪方法。
When a charged particle is in a magnetic field, it tends to travel along that field ' s lines of force, spiralling as it goes
當一個帶電微粒在
磁場中時,它會
傾向于沿著
磁力線螺旋運動。
Are you power cycling the devices after setting the write protect dip switch to off ( switch 1 )
你是使在設定之後騎腳踏車兜風裝置有力量那寫保護
磁傾角開關到離開(開關1 )
I feel the phoenix dip slightly in altitude, a familiar sensation indicating we ' re on final approach. whatever ' s in the needle ken gave me works damned fast. i can almost see him again. " ken ? " i whisper
我在高度中些微地感覺鳳凰城
磁傾角,指出我們在最後的方式上的熟悉感覺。無論什麼在針肯恩中極快速地給予了我工廠。我能幾乎再一次看見他。 "肯恩" ?我耳語。
Firstly, in the magnetic field varying from 0mt to 1200mt, we have tested the faraday rotation angle of the three kinds of crystals. at different aspects such as nonlinear aspects, the influence on rotation angle caused by coating the crystals and inclining them the experiment has been finished. and the experiment achieved the following results : 1
從faraday效應的
磁致非線性特徵、鍍增透膜對faraday旋光角的影響、晶體
傾斜對旋光角的影響三個有關旋光角的方面進行了實驗,得出: 1 、 faraday旋轉隨外
磁場變化的非線性變化曲線; 2 、鍍增透膜前後晶體旋光角的變化比較曲線; 3 、晶體
傾斜前後旋光角變化比較曲線。
Because the magnetic field of the earth is inclined in most places ( it points not only north but also downward in the northern hemisphere and upward in the southern ), a magnetotactic bacterium can follow a magnetic field line up or down to its desired destination
由於地球上大多數地區的
磁場是
傾斜的(在北半球,
磁場不只是往北指,還向下指;在南半球則是向上指) ,
磁感細菌可以根據
磁場的上下方向,而到達它的目的地。
The magneto - elastic motion equation and the electrodynamic equation of the thin strip conductive plate in a leaning magnetic field are derived on the basis of the principle magneto - elastic theory, and the characteristic equations of the vibration of the plate supported along two long sides are obtained as well
摘要以
磁彈性基本假設為出發點,給出了
傾斜
磁場中無限長條形薄板的
磁彈性運動方程及電動力學方程,並推得了兩長邊簡支薄板的
磁彈性振動特徵方程式。
Without electricity, we can neither watch tv, listen to the tape, nor chat on line
沒有電,我們裝不手錶電視,
傾聽
磁帶,亦不閑談于罐中在線。
Develop, research, produce and sell 13 types of functional products with national patent. its products cover far infrared nb element magnetic healthy bedclothes and raiment, far infrared warm - keeping health - care underwear, anti - radiation raiment, anti - ultraviolet cool textile and bedclothes against asthma due to dust mite
是江蘇堂皇集團的核心企業,它以高新科技為依託,傾力開發研製生產銷售十三項國家專利功能產品:遠紅外nb素磁性健康寢具服飾,遠紅外保暖保健內衣,防輻射服飾,防紫外線涼爽織物,防塵蟎性哮喘寢具。