Drop the needles on the paper and calculate the percentage that fall on a line. With enough attempts, the answer should be the needle length divided by the width between lines, all multiplied by 2/pi.
将针随便丢在纸上，然后计算出落在线上的针的百分比，随着尝试次数的足够多，最终这个百分比将越来越逼近针的长度除以格子的宽度再乘以2/pi。
Keep a bag handy. Slip a pencil, paper, articles or mail to read, clothing darning needle and thread.
准备一个手边的袋子，放入铅笔、纸、要读的文章或书信、缝衣针和线。
He made some small holes in the paper with a needle, which formed the shape of a flower.
他用针在纸上刺了些眼儿，眼儿连成了花的形状。
To tear the paper or pick out the fiber using the needle, then to find the two color on the same one fiber .
撕开纸张或用针挑出纤维直接观察，一根纤维上有两种颜色。
Each dart consisted of a hollow steel needle with a paper tail.
每个飞镖由一个带着纸尾巴的空心铁针组成。
This paper mostly introduces the illumination technology of vehicle dashboard at present in our country, particulaly introduces the dial illumination, the needle illumination and the LCD illumination.
主要介绍国内目前的汽车仪表照明技术，分别从表盘照明、指针照明、液晶照明等几个方面予以说明。
The paper talks about the theory on transforming single needle sewing machine into overedging machine.
简述单针缝纫机改造成包边机的原理。
This paper reports a systematic study on the needle-coke grain orientation as a function of radial position of a premium grade graphite electrode using image analysis.
本文采用图像分析的方法，系统地研究了一种优等石墨电极中针状焦晶粒的取向与其在电极中的径向位置的依赖关系。
This is a paper for the therapeutic effects of 35 nocturia and 32 urinary and fecal incontinence with needle-pricking method.
本文报道用针挑刺疗法治疗夜尿症35例、尿便失禁32例的疗效。
The centrifugal compound casting process of needle-like bainite ductile iron roller was establish in this paper.
本文制定了针状贝氏体球铁离心复合轧辊的生产工艺。
Two key questions in test running homemade PET spunbonded needle punched nonwovens production line are introduced in the paper. Method to solve these key questions are explained.
介绍了国产聚酯纺粘针刺非织造布生产线生产调试过程中的两个关键问题，说明了调试过程关键问题的解决办法。
Development and manufacturing from the opening, carding, lapping machine needle into the entire line of paper craft and equipment.
开发和制造从开松、梳理、铺网机针刺成卷整线工艺和设备。
Summary 38 cases of lung and mediastinum diseases diagnosed by percutaneous needle biopsy were reported in this paper.
本文报导了38例经皮针吸活检诊断肺及纵隔病变。
This paper introduces the different pile warp knitted fabrics knitted on single and double needle bar warp knitting machines and its application in practice, and gives some mature technology.
介绍了在单针床经编机和双针床经编机上的不同绒类织物，及在实际中的应用，并且给出了部分成熟工艺。
This paper introduces the motion of CAM hook needle of the linking machine, and describes the motion locus of.
介绍了合缝机三角钩针的组合运动，描述了三角钩针针尖运动的轨迹。
The paper also analyzed the crystal defeat formed in the process of growth and put forward to the solution, furthermore, the mechanism of needle - like growth was discussed.
并对晶须生长过程中所形成的各种晶体缺陷进行了分析，提出了解决办法。同时对羟基磷灰石晶须针状生长的结晶学和界面动力学机理进行了探讨。
A new device for measuring run out error of needle valve seat′s cone surface is proposed. The calculating and estimating methods of the error are also described in the paper.
推出了一种新的针阀体座面圆跳动误差测量装置，介绍了误差的计算与评定方法。
The paper should give an idea of the significance of even the smallest details and execution caracteristics of a latch needle in terms of an optimum knitting process.
本文阐述了基于优化针织编织过程的舌针的细节设计和运动特性重要性概念。
This paper has presented a graphic designing method for the tubular fairies knitted on double needle bar warp knitting machine.
本文提出圆筒双针床经编组织的图解设计方法。
In this paper, the influence of flow coefficient of injector hole, hole diameter and needle lift on emission is studied through contrast experiment of different injectors.
本文通过对柴油机配置不同喷油器所进行的排放对比试验，研究分析了喷油器喷孔流量系数、喷孔直径、针阀升程对排放的影响。
Throngh analysis and comparing, this paper brings forward a new assume, which use gait analysis to validate needle-knife theory. It is a new idea.
通过分析比较，提出了利用步态分析来验证针刀理论的新构想，是一种全新的思路。
The needle blight disease of spruce, which is new to china, is described in this paper.
本文报道了在我国新发现的一种病害，云杉叶疫病。
The difference between spunbonded nonwovens needle-punched process and short fiber needle-punched process is introduced in the paper.
介绍了纺粘法非织造布针刺生产工艺与短纤针刺工艺的不同。
Using needle-to-plane electrodes plasma discharge in water, active species generated has been studied in this paper.
本文对尖-板电极水中脉冲放电产生的活性粒子进行了研究。
This paper is about the texture segmentation technology on lace image and the method of separating needle region and distinguishing.
本文阐述了对花边图像采用纹理分区技术，进行针法区域分割进而识别的方法。
The present paper has described the die made by chromium car - bide for forming mass spectrometer needle and double curved surface glass tube in surface analyzing instrument.
介绍了采用碳化铬硬质合金制作质谱计和表面分析仪器中的双曲面玻璃管的成形模具。
An interchangeable method of outer ring assembly of needle roller bearings with or without inner rings is introduced in this paper.
介绍一种有内圈和无内圈的滚针轴承外圈组件互换的方法。
The present paper has introduced in detail the pilot production and research and development of cemented carbide printing needle with high ductility used for electronic printer.
本文介绍了电子打印机用高韧性硬质合金打印针的研制与开发。
Package form: Customer could choose all-plastic package or paper plastic package, and the needle spec ups to the contact.
包装形式︰具备全塑包装、纸塑包装等多种形式，客户可自行选择，带针规格按客户合同。
In this paper a new method for measuring 3-d displacements, needle projection method with holographic interferometry, is developed.
本文提出一种新的三维位移测量方法：标针投影全息干涉法。
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