摘要：We propose a new 3D inversion scheme to invert the near-and transition-zone data of CSAMT with topography *** this new method,the earth was discretized into unstructured tetrahedra to fit the ragged topography and the vector fi nite-element method was adopted to obtain precise responses and good *** simulate the attitude and shape of the transmitter,we divided a long-grounded transmitter into dipoles and integrated these dipoles to obtain good responses in the near-and transition-fi eld ***,we designed an L2 norm-based objective functional and applied a standard quasi-Newton method as the optimization method to solve the inverse problem and guarantee steady *** tested our 3D inversion method first on synthetic data and then on a field dataset acquired from select sites near Changbai Mountain,*** both tests,the new inversion algorithm achieved excellent fitting between the predicted and observed data,even in near-and transition-fi eld zones,and the inversion results agreed well with the true *** fi ndings reveal that the proposed algorithm is eff ective for 3D inversion of CSAMT data.

摘要：针对10MeV大功率辐照加速器研制的需求,对其磁场系统进行研制,此磁场系统由聚焦系统和扫描系统组成。根据束流加速输运的磁场要求,进行了磁场设计、模拟计算。聚焦系统由6个聚焦线圈组成,每个线圈约束磁场的径向均匀区为4cm,为加速管聚束段提供横向约束磁场,实测磁场分布与束流要求计算曲线分布基本吻合。扫描磁铁采用分体结构,扫描宽度为±334mm,最大扫描频率为15s-1,通过优化磁极结构,使扫描均匀度达到92%。磁场系统各项性能均满足10MeV电子直线辐照加速器的技术要求并稳定运行至今。

摘要：航空电磁法的探测能力受飞行高度、发射波形、发射磁矩和发射基频等因素的影响,致使不同分量间的勘探能力存在差异.航空电磁如对所有磁场和磁感应分量、on-和off-time数据进行观测和解释,不仅数据量大、耗时长,而且出现大量冗余数据.目前国内针对此问题尚无系统解决方法.本文针对吊舱式直升机航空电磁系统,采用积分方程法求解频率域响应,经汉克尔变换转换到时间域,计算了地下三维目标体的B和dB/dt时间域响应.利用异常体响应与背景场响应作比值,并通过设定响应阀值定义最大勘探深度,进而分析不同发射波形、不同分量以及on-和off-time期间的航空电磁系统的探测能力.基于本文分析手段,可根据实际勘探目标,确定一套探测能力较强的航空电磁最佳参数组合,为野外测量和数据处理提供技术指导,高效完成勘探任务.

摘要：微型核电池是目前航天器仪器、设备理想的电源。63Ni是镍电池的核心工作物质。通过在反应堆中辐照高丰度的稳定同位素62Ni,能产生放射性同位素63Ni。为保证62Ni的丰度达到要求,本文开展了62Ni同位素的分离制备研究,进行了磁场及束流输运计算,对离子源及接收器口袋进行了改进设计,制定了电磁分离法分离高丰度62Ni的工艺流程。利用现有的电磁同位素分离器,开展了用电磁分离法分离高丰度、高纯度62Ni稳定同位素的实验,最终获得了丰度≥90%的62Ni同位素。

摘要：根据拟南芥RS基因的编码序列设计引物,利用PCR技术从pGADT7-RS重组质粒上扩增到RS基因编码区476 bp片段。利用双链RNA介导的基因沉默技术,构建RS基因沉默表达载体,为进一步研究该基因在植物与蛋白激发子HpaGXoo互作中的功能及其作用机制奠定基础。首先将RS基因片段连接到pUCm-T载体上,用Pst I/BamH I和Pst I/Xho I分别对pUCm-RS重组载体进行酶切,得到2个RS基因片段;先后将其连接到用相应限制酶酶切的pBSSK-in载体上,构建成pBSSK-RS-in-RS重组载体,该重组载体中的2个RS片段大小一致,反向重复;最后用Sac I/Kpn I酶切pBSSK-RS-in-RS载体得到RS-intron-RS片段,连入表达载体pCAMBIA1301中,构建成该基因的沉默表达载体。

摘要：论述本科毕业论文(设计)的重要意义和存在的问题,对本科毕业论文(设计)与专业实习结合的可行性、有效方法以及结合过程中需要关注的重点问题进行了深入探讨。

摘要：The robustness of LQG designing for latitudinal movement of ship is mainly discussed, when its hydrodynamic parameters fluctuate around criterion value at random on the proportional distributing. When a given ship state at the speed of 18 kn and the course of 45° under Rank 5 state of sea, and the hydrodynamic parameters of the ship fluctuate at random on the proportional distributing with a range of ± 10% , ± 20% , ± 30% , the robustness of muhivariate LQG designing for ship is analyzed with applying the probability modeling of relative controlling effect, The result of simulating shows that when the hydrodynamic parameters of ship fluctuates the relative controlling effect of the LQG designing submit to normal distribution and the mean value of relative controlling effect has no remarkable changes comparing to that without perturbation of hydrodynamic parameter,

摘要：炭柱调压器是飞机电源系统稳定发电机输出电压的关键部件,该设备的性能好坏对飞行安全有着直接影响。针对炭柱调压器故障检测和维护难度大的问题,该文进行“炭柱调压器炭柱粘连故障的低频脉冲扫描检测电路”的设计和应用,实现对疑似故障炭柱调压器进行快速、有效、准确的故障检测,以筛选出故障设备和非故障设备,避免对非故障调压器实施误维修,减轻航空调压器的修理工作强度。该文针对电磁铁的低频脉冲电压驱动电路,炭柱伸缩时阻压转换电路,炭柱电阻电压采集电路进行设计,并将它们连接在一起构成总电路,最终获得基于低频脉冲扫描的炭柱调压器故障检测电路,实现对调压器故障的高效维修。

摘要：The construction of water conservancy projects in cold regions experiences freezing-thawing cycles,which can greatly change the engineering properties of soil and have a significant impact on the construction of *** Hydropower Station(LHS),is a controlling station with the largest installed capacity among the 7 middle reach projects in the Yalong River,the secondary tributary of the yangtze *** is located in a seasonally frozen soil *** on the measured data of air and ground temperature in winter in the dam core wall,the freezing-thawing variation of gravelly soil and contact clay during the filling process of the core wall are compared and analyzed,then the main impact factors of the freezing-thawing variation of soils are *** results show that under the influence of air temperature,soil freezes unidirectionally from ground surface downward and deepens gradually,and the thawing processes are different at the aspects of thawing direction and *** temperature and physical properties of soil including soil type,moisture content and dry density affect the freezingthawing processes of *** the impact of engineering construction is more remarkable than natural *** engineering construction affects soil temperature and freezing-thawing process by controlling the initial temperature of soil,the speed and duration of the technological conversion of paving,compaction,and the length of placed duration at *** to the long placed duration of soil with the slow construction method,the initial temperature of soil gradually reduces,the heat transfer process inside soil is *** the internal heat of soil releases,the decreasing rate of ground temperature of soil at different depths is fast and the frozen depth *** due to the short placed duration of soil with the rapid construction process,the initial temperature of soil is high,high internal heat of soil is supplied every day,and the heat transfer process in

摘要：为了研究供应链赊销交易中知情委托方向代理方进行信号显示的问题,考虑由一个供应商和一个零售商组成的二级供应链,双方进行赊销交易。零售商作为核心企业,拥有销售能力的私人信息。基于显示原理,首先设计了具有激励性质且保证供应商单独可获利的低信息密度最优配置,并分析了博弈的完美贝叶斯均衡。结果表明,知情零售商通过提供低信息密度最优配置向供应商传递信号,但存在信号成本,具体表现为:契约呈现"低端不扭曲,高端向上扭曲"特性;且对高能力零售商的初始资金有门槛要求。其次,通过分析知情零售商提供的事中有效配置发现,当供应商对零售商所属类型的信念满足一定条件时,低信息密度最优是事中有效的,此时博弈存在唯一的完美贝叶斯均衡。否则,由事中有效确定的均衡配置集弱帕累托占优于低信息密度最优;高能力零售商的信号传递成本相对降低,具体表现为:"高端向上扭曲"的程度相对较低,且向供应商提供初始资金的门槛要求也更低。本文的研究对供应链管理中,知情委托方的赊销契约设计问题提供了一定的理论基础和实践指导。