扫描

Objective To explore the effects on images from the space location of spectrum and scanning parameters,and summarize the technological essential and application hints.Methods 65 patients were scanned in brain with magnetic resonance spectroscopy,the location and the size of region of interesting and other scanning parameters values （FOV,frequency matrix,phase matrix,saturate cingulum,etc.） were changed intentionally,the values of full width at half maxium and water suppression lever were recorded.A preliminary evaluation of the resulted waves and the relationship between the parameters data and the quality of the MRS waves were probed.

目的 观察波谱空间定位和扫描参对图像质量的影响，并初步小结应用要点方法对65例头颅检查的受检者行磁共振波谱扫描，有目的地改变感兴趣区域的位置、小和其他参数设置（FOV、频率矩阵、相位矩阵、预饱和带等），记录预扫描后系统显示的半高宽、水抑制程度等数值，并对扫描后显示的图像质量进行初步评价，探讨些数值与波谱质量之间的关系。

objective to explore the effects on images from the space location of spectrum and scanning parameters'and summarize the technological essential and application hints.methods 65 patients were scanned in brain with magnetic resonance spectroscopy'the location and the size of region of interesting and other scanning parameters values （fov'frequency matrix'phase matrix'saturate cingulum'etc.

目的 观察波谱空间定位和扫描参数对图像质量的影响，并初步小结应用要点。方法对65例头颅检查的受检者行磁共振波谱扫描，有目的地改变感兴趣区域的位置、大小和其他参数设置（fov、频率矩阵、相位矩阵、预饱和带等），记录预扫描后系统显示的半高宽、水抑制程度等数值，并对扫描后显示的图像质量进行初步评价，探讨这些数值与波谱质量之间的关系。

The raw data was processed by using axial, coronal and double oblique multi-planar reformation; Images obtained were graded in terms of quality with a 5-point scale(5=excellent, 4=good, 3=fair, 2=poor, and 1=nondiagnostic). In grading image quality at axial MPR, The radiologic specialists focused on the subarcuate fossa, tendon of tensor tympani, facial recess, vestibular aqueduct and pyramidal eminence, In grading image quality at coronal MPR, attention was given to the scute, crista transversa, fenestra cochleae, lateral malleal ligament and snake eyes signature of cranial nerve, In the grading of the image quality at double oblique MPR, the radiologic specialists concentrated on the malleus, incus, stirrup bone, upper bony semicircular and aquaeductus fallopii, and then to implement statistical analysis. In order to choose the minimum tube current values and the maximum pitch that can satisfy the diagnosis request, image quality of axial, coronal and double oblique reformation images was compared with different tube current groups. 15 ears of volunteers were used to test the validity with the scanning parameter. Subsequently noise, MTF and dose length product were measured by phantoms in different tube current and pitch, the parameters obtained were compared and taken into statistics analysis.

扫描模式使用临床常用的颞骨螺旋扫描方式：管电压120 kV，准直宽度20×0.6 mm，视野200 mm，重建矩阵512×512，旋转时间1 s/r，重建层厚0.6 mm，重建间隔0.3 mm，分别改变管电流(380、300、200、160、120和80 mA)和螺距(0.8、1.0和1.2)进行扫描和重建，然后对颞骨进行横断面、冠状面和双斜面多平面重组，于重组后的横断层面图像上选取弓形下窝、鼓膜张肌腱、面神经隐窝、前庭导水管和锥隆起5个解剖结构，冠状面重组图像上选取盾板、横嵴、蜗窗、面神经的蛇眼征和锤骨外侧韧带5个解剖结构，双斜面重组图像上选取锤骨、砧骨、镫骨、上骨半规管和面神经管5个解剖结构，在双盲的情况下由放射学专家分别对各管电流和螺距下扫描的重组图像进行评分，随后进行统计学处理，从中筛选出满足诊断要求的最低管电流值和最大的螺距，分别采用患者25例(15耳)用该管电流值和螺距验证其可行性；然后利用模体分别测试各管电流和螺距下的图像的空间分辨率、噪声及其剂量长度积，并对测试所得参数数值进行比较和统计学处理。

In order to improve scan precision of the laser galvanometer scan system, especially when scan area is large, the reasons of graphic distortion are analyzed in this paper when the laser galvanometer scan system is running, and the whole bag of compensating tricks are put forward for every reason of corresponding graphic distortion.

针对如何提高振镜式激光扫描的扫描精度，特别是当扫描区域较大时的精度问题，文中展开了对振镜式激光扫描时图形畸变原因的分析，并对每一种误差产生的原因提出了校正补偿的办法。

Results When scanning speed of frequency-tripled Nd : YAG laser was no more than 80 mm/s, the thermal damage rate was lower, and the aperture size of microperes varied indistinctively.

结果激光束扫描速度小于或等于80mm/s，热损伤率较低，微孔孔径变化不明显；随着激光束扫描速度的加快，热损伤率增大，孔径随之增大；当扫描速度加快至500mm/s，孔径开始缩小；当扫描速度为600mm/s，激光束不能穿透真皮基质形成微孔。

Internal cylindrical drum machanistic imagesetter scan records section of the main characteristics is that sencitivity is adsorbed on drums of intine, phototypesetting, drum does not rotate, but by scanning head side to side movement in turnused mediumso imaging, usually on the exposure from drum 360 degree of 270 degrees as a scan of the film to prevent blurry due to reflection.

边方滚筒扫描式激平照排机的扫描纪录局部的次要特不面是，感平质料被吸附在滚筒的边壁上，照排时，滚筒并不不停不静，而是靠扫描脚一背回旋扭不停，一背移不静在感平质料上曝平不败像，凡是只诳骗滚筒360量洋的270量息为感平胶片的扫描区，以避免不屈射引起的暧昧不隐象。

Workers can also key in numeric data" such as quantities" while scanning.

扫描速度是指单位时间内扫描光束在扫描轨迹上的扫描频率。

This paper discuss the key techniques used in Stroke to Raster Scan Conversion: The fundamentals of video scan conversion. A practical scan conversion system based on CPLD is proposed, in which CPLD is used to control SRC system flexibly and it realizes stroke to taster scan display system conversion.

本论文分析了随机扫描到光栅扫描转换的关键技术，即视频扫描转换的基本原理，并给出了一种实际实现方案，构建了以CPLD为控制核心的扫描转换硬件系统。

Some basic equations of dual beam scan are derived,such as,the position vector for the incident point,the scalar expression for reflected ray,scan pattern on observation plane ect.

文摘：应用几何光学理论研究了多光束转镜扫描场的非对称性，导出多光束扫描入射点位置矢量、反射线标量表达式、观察面上的扫描轨迹方程，并研究了扫描远场的非对称性。

This paper presents a new selective trigger scan chain architecture by changing traditional scan design using a scan register,whose length is equal to that of scan chain.

利用一个和扫描链等长的扫描移位寄存器，对传统扫描链进行改造，提出了一种新型的选择触发的扫描链结构。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。