搜索结果: 1-15 共查到“理学 MV-W”相关记录15条 . 查询时间(0.066 秒)
15 MV医用直线加速器X射线束的MCNP模拟
医用电子加速器 X射线束 百分深度剂量 蒙特卡罗
2022/3/16
高能医用直线加速器在放射治疗中的应用越来越广泛，其辐射源项及屏蔽防护研究一直是人们关注的重点。应用MCNP（MonteCarloN-ParticleTransportCode）软件对Clinac23EX型医用直线加速器产生的15MVX射线束进行模拟。依据厂家提供的机头内部件的材料组成和几何尺寸，构建X射线模式的加速器机头精细模型，计算了不同照射野下X射线束在水模体中的百分深度剂量（Percenta...
We give a realization of the infinity crystal for affine sl(2) using decorated polygons. The construction and proof are combinatorial, making use of Kashiwara and Saito's characterization of the infin...
2.5 MV特快速瞬态过电压发生器
特高压 气体绝缘开关设备 特快速瞬态过电压 电容传感器
2012/7/2
气体绝缘开关设备(gas insulated switchgear，GIS)以其占地面积少、密封性好，受环境影响小，运行可靠、维修周期长等优点在中国电网中得到了广泛应用。在330 kV以上电压等级的系统中，开关动作产生的特快速瞬态过电压(very fast transient overvoltage，VFTO)对系统有很大危害。为满足特高压GIS中VFTO的模拟，利用6 MV敞开式冲击电压发生器与...
On the possibility of obtaining MOSFET-like performance and sub-60 mV/decade swing in 1D broken-gap tunnel transistors
obtaining MOSFET-like performance sub-60 mV/decade
2010/11/25
Tunneling field-effect transistors (TFETs) have gained a great deal of recent interest due to their potential to reduce power dissipation in integrated circuits. One major challenge for TFETs so far h...
A Localization in MV-algebras
Localization MV-algebras
2010/12/10
In this document we consider a way of localizing an MValgebra.Given any prime filter F we find a local MV-algebra which has the same poset of prime filters as the poset of prime filters comparable to ...
The purpose of this paper is to apply the theory of MV polytopes to the study of com-ponents of Lusztig’s nilpotent varieties. Along the way, we introduce reflection functors for modules over the non-...
6 MV Wedge Photon Beam Profiles with the Fricke Xylenol Gel Dosimeter
Fricke Xylenol Gel physical filter wedge beam profiles
2010/7/8
Wedged beam are often used in clinical radiotherapy to compensate missing tissues and dose gradients. In this work, the Fricke Xylenol Gel (FXG) dosimeter was used for 6 MV photons radiation wedge fie...
MV级EPID成像中靶材料与厚度的优化选择
Monte-Carlo方法 MV级 靶 Geant4 EPID
2011/8/17
MV级电子射野成像系统（EPID）产生的图像相对于kV级对比度差，其中靶的材料和尺寸是一重要因素。采用Monte-Carlo软件包Geant4程序对6 MV医用直线加速器进行模拟，对MV级EPID成像中靶材料与厚度进行优化选择。计算结果表明，低原子序数的薄靶有利于改善成像质量，在无均整器的情况下，3 mm厚的Cu靶或10 mm厚的Al靶更适用于6 MV的电子射野成像系统。
Dose Rate Influence on Deep Dose Deposition Using a 6 MV X-Ray Beam From a Linear Accelerator Accelerator
dose rate x-ray beam dosimetry deep dose deposition
2010/7/5
Linear accelerators used in radiation therapy treatments usually provide the capability of irradiating with different dose rates. The medical physicist may choose arbitrary the dose rate to use, altho...
A Revised Calibration of the MV-W(O I 7774) Relationship using Hipparcos Data：Its Application to Cepheids and Evolved Stars
Evolved Stars MV-W Cepheids
2009/6/16
A Revised Calibration of the MV-W(O I 7774) Relationship using Hipparcos Data：Its Application to Cepheids and Evolved Stars。
用变分法计算带有质量的Wilson费米子的格点Schwinger模型中矢量介子的质量M,从而求出M、对费米子质量m的变化率Mv/m(m=0处),结果与连续理论的准确解十分接近.
The Investigation of Nova-like Variable MV Lyr during the 1999--2001 Years
Cataclysmic variables “anti-dwarf novae”
2009/5/19
A peculiar nova-like MV Lyr was investigated. The CCDobservations
ofMVLyr were continued in Crimea during the outbursts and
quiescent states. Last year its behavior became non-typical for “anti-dwar...
国际空间站蜘蛛太空织网录像被编成MV（图）
蜘蛛 太空织网
2008/12/1
北京时间2008年11月29日消息，据物理学家组织网报道，美国科罗拉多大学波尔多分校11月14日利用“奋进”号航天飞机将织网蜘蛛和蝴蝶幼虫等有效载荷送到国际空间站上，结果这些小东西这在科学家、宇航员和新闻媒体中引发轰动效应，网上还出现了一段蜘蛛伴随着音乐《小蜘蛛》(The Itsy-Bitsy Spider)在国际空间站织网的MV。
X线是人类了解和应用最多的一种放射线，每当人们研究一种新的辐射类型的生物效应时，都要与之相比较。同样，在各种辐射类型诱发人染色体畸变的研究中，已经有大量的实验资料将丫线、中子、电子及其他粒子流与X线作了比较。但是，在进行这种比较之前，首先要对X线本身有更多的知识，即应了解光子能量不同的X线诱发染色体畸变的效能如何，这正是本工作的目的所在。为此，我们选用目前临床诊断和治疗中经常使用的60kV, 1...