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1.
国家"十二五"工程将在哈尔滨工业大学建造一台空间辐射地面模拟装置(SESRI),该装置能够模拟空间辐照环境,对研究离子辐照材料、生命体等具有重要意义。SESRI主要由双ECR离子源,直线注入器,同步环和3个高能实验终端组成。周长为43.9 m的同步环作为装置的核心部分,能够向3个实验终端输送离子种类多、能量范围广的粒子束。为了保证环内有足够的粒子数,注入系统的设计至关重要,SESRI同步环采用多圈注入方案,并利用ACCSIM程序模拟粒子真实运动情况。结果表明,粒子的注入效率为85.5%,离子数增益可达17.1,可满足设计要求。Space Environment Simulation and Research Infrastructure (SESRI), which is one of the large-scale scientific projects proposed in National Twelfth Five-Year Plan of China, will be constructed in Harbin Institution of Technology. The SESRI project dedicated to space radiation consists of two ECR ion sources, a high intensity ion linac, a synchrotron and 3 research terminals. As the key part of the complex, a 43.9 m synchrotron can provide broadest energy range and variable ion beam for each terminal. To obtain required intensity in the synchrotron, the injection system is significant. A multi-turn injection scheme is adopted in the synchrotron and the injection process is simulated by ACCSIM with multi-particle tracking method. The results show that the injection efficiency and intensity gain factor can reach 85.5% and 17.1 respectively. The multi-turn injection system can meet the design requirement.  相似文献   

2.
平面与空间转子体系的双波函数研究   总被引:10,自引:1,他引:10       下载免费PDF全文
刘全慧  王发伯 《物理学报》1991,40(10):1562-1566
本文给出了平面与空间转子体系的双波函数论,精确地得到了平面与空间转子体系的经典力学运动方程,并探讨了这两个体系通常量子论中的有关问题。 关键词:  相似文献   

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基于Pareto类遗传算法的平面叶栅多工况优化   总被引:1,自引:0,他引:1  
将叶型参数化、试验设计方法、神经网络算法与Pareto类遗传算法相结合,发展了一种平面叶栅多目标优化设计方法.在该算法中,为提高优化效率,提出了并行神经网络算法和改进了NSGA-Ⅱ算法.以极小化三个工况点的总压损失系数为目标函数,将该优化方法应用于某平面叶栅多工况优化设计.与初始叶栅相比,优化后叶栅的总压损失系数在三个工况均有一定的减小,说明该优化方法是有效的.  相似文献   

4.
多联机双风轮系统拍振分析与性能优化研究   总被引:2,自引:0,他引:2  
各品牌的中央空调多联室外机均采用双风轮系统,都存在不同程度的低频脉动异音,异音呈低频特性,易让人产生烦躁感.双风轮系统在旋转基频比较接近的情况下运转时,旋转噪声叠加后产生拍振异音,其频率等于双风轮的旋转基频差.旋转噪声是拍振腹能量的主要来源.本文设计了新三叶风轮,采用新三叶风轮与原四叶风轮组合方式运行.同时测试两风轮的...  相似文献   

5.
为满足ITER相关设计准则,采用有限元分析方法,以ITER装置单个端口气体注入管线为例,对注入管线开展线弹性应力分析并进行了设计优化。分析结果表明原管线柔性未得到有效限制,在较大形变处增设支撑是必要的。优化后的分析结果显示注入管线在限制柔性的同时管线中的应力值满足设计规范的评判标准,没有出现塑性塌陷、局部失效和棘轮效应,而且支撑等部件的支反力减小33%。验证了优化方案的可行性,最终管线结构的可靠性和安全性得到了明显的改进。  相似文献   

6.
KYCORE程序是中国核动力研究设计院开发的径向MOC(特征线方法)与轴向SN耦合三维中子输运程序。KYCORE将二维MOC与一维SN通过角通量实现高精度耦合,并通过粗网有限差分实现快速收敛,是目前可工程化应用于三维中子输运计算中精度最高的方法之一。介绍了2D/1D计算与加速理论,并通过与蒙特卡罗程序的计算对比,数值验证了KYCORE三维中子计算的准确性与高效性。  相似文献   

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KYCORE程序是中国核动力研究设计院开发的径向MOC(特征线方法)与轴向SN耦合三维中子输运程序。KYCORE将二维MOC与一维SN通过角通量实现高精度耦合,并通过粗网有限差分实现快速收敛,是目前可工程化应用于三维中子输运计算中精度最高的方法之一。介绍了2D/1D计算与加速理论,并通过与蒙特卡罗程序的计算对比,数值验证了KYCORE三维中子计算的准确性与高效性。  相似文献   

8.
施炜  黄黎蓉  段子刚  冯玉春 《光子学报》2006,35(9):1313-1316
根据多量子阱中注入载流子的输运机制,计算了多量子阱中注入载流子的非均匀分布.引入不均匀度参量Asy来衡量载流子分布的不均匀程度,分析了各种敏感因素对载流子非均匀分布的影响.指出注入载流子分布的非均匀性,随量子阱数、注入电流、量子垒高度的增加而显著增加,随工作温度的升高而减小.  相似文献   

9.
提出了一种基于方向性靶标和多约束优化的双目相机标定方法。新型方向性平面靶标能够判断靶标的旋转方向,并对每个标定角点进行编码,以保证双目相机在拍摄到局部靶标的情况下依然能够完成同名点匹配,进而完成双目相机标定。根据方向性靶标建立双目相机标定模型,引入用于描述平面靶标姿态的天顶角和方位角,通过天顶角和方位角筛选出在不同位置上的靶标姿态均具有明显差异的图像作为标定图像,这提高了双目标定结果的稳定性;结合靶标的三维几何信息,建立了多维度约束的双目参数优化模型,提高了双目标定结果的精度。实验结果表明,与传统的张氏标定方法相比,所提出的标定方法能够有效提高所获得的标定结果的稳定性和精度;通过对标准量块进行多次测量,进一步验证了所提方法的有效性。  相似文献   

10.
研究了不同垒厚对InGaN/GaN多量子阱电注入发光性能的影响及机理。实验发现,当GaN垒层的厚度从6 nm增大到24 nm时,垒厚的样品发光强度更强,而且当注入电流增加时,适当增加垒厚,可以更显著增加发光强度。进一步结合发光峰位和光谱宽度的研究表明,由于应力和极化效应的存在,当垒层厚度在6~24 nm范围内时,适当增加垒层厚度不仅会使得能带的倾斜加剧,减少电子泄露,而且也会增加InGaN阱层的局域态深度,从而改善量子阱的发光性能。  相似文献   

11.
Improved Computer Program for Magnetron Injection Gun Design   总被引:1,自引:0,他引:1  
Gyrotron has received extensive attention owing to its high-power capability, especially when the wavelength shrinks below the millimeter-wave range. The electron beam of a gyrotron is typically generated by a magnetron injection gun (MIG). For high cathode current density, the MIG may operate in a region that combines temperature limited and space-charge limited emissions. An improved computer program for electron gun design is appropriate for MIGs that operate between space-charge limited and temperature limited emission. Moreover, the initial input formation of the program resembles that of the EGUN code. Analysis of a Pierce electron gun and MIGs reveals that the stimulated beam current appears consistent with the measured results. However, EGUN simulation results in which the cathode emitters of MIGs are chosen for the temperature limited emission differ from those of our simulation results. This difference is most likely owing to that the initial emitting energy can not be completely described in the EGUN simulation. Finally, the improved computer program is used to design a MIG for a Ka-band, TE01 mode gyro-TWT.  相似文献   

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分析比较了基于锁相环技术和基于注入锁定技术的两种光电振荡器的特性,推导了两种光电振荡器的噪声传递函数,并进行了实验验证,得出了这两种技术应用于光电振荡器的相似性和各自的优缺点.由于光纤对温度的高敏感性,采用这两种技术的光电振荡器都存在着易失锁的问题.为解决这一问题,分别分析了两种光电振荡器输出信号与参考信号间的相位关系,基于此关系设计了锁定状态监测和反馈系统,并实验验证了系统的有效性.  相似文献   

14.
Journal of Applied Spectroscopy - A simple, accurate, novel, safe, and precise method was developed for the estimation of erlotinib hydrochloride in tablet dosage form using a mixture of methanol...  相似文献   

15.
Journal of Applied Spectroscopy - A reproducible, sensitive, and cost-effective spectrofluorimetric method has been developed for quantification of the drug ibrutinib in bulk and in its oral...  相似文献   

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任健  武林平  申卫东 《计算物理》2015,32(4):431-436
基于并行应用支撑软件框架JASMIN的辐射流体与粒子输运耦合程序RHSn2D,采用最小邦元固定处理器数目的并行策略,计算实际模型的并行规模扩展至8192核,并行效率约为16%.集成程序时间分析,验证软件框架底层MPI并行环境聚合通信对于并行优化算法(尤其是辐射流体计算时间)的影响.  相似文献   

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《Journal of voice》2019,33(6):948.e23-948.e29
PurposeThe Dysphonia Severity Index (DSI) is an objective multiparameter index of voice quality that measures and describes overall voice quality. Some studies have suggested that the reliability of devices for DSI measurement should be examined. We explored the feasibility of DSI measurements using the Dr. Speech (DRS) device, verified its effectiveness for clinical voice measurements and intradevice reliability, and examined the correlation between the DSI and self-evaluations of voice problems.MethodsSeventy adult participants (including individuals with voice problems and healthy adults) underwent objective and subjective voice assessments. These data were then used to establish a DSIDRS model and test the intradevice (DRS device and Praat software) reliability. The clinical validation of the DSIDRS was conducted by measuring the DSI of six other participants and comparing the observed and predicted perceived voice quality as expressed by the G score (of the GRBAS scale). Moreover, the relationship between the DSI measurements and participants’ self-evaluations of voice problems was investigated by analyzing the correlation between the DSI and the Voice Handicap Index (VHI).ResultsThe DSIDRS discriminated 80% of participants’ voice quality ratings. There were strong correlations between the DSI and variables measured by the DRS device and Praat software. Furthermore, there was no significant correlation between the DSIDRS and VHI.ConclusionThe DRS device can perform DSI measurements. Objective voice measurements and perceptual voice ratings reflected different aspects of vocal function and its effects. These factors should be considered in clinical practice settings.  相似文献   

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