基金最佳使用计划

本文给出了基金存款策略的数学模型.对于基金M使用n年的情况而言,首先把M分成n份,其中第i(1≤i≤n)份存款xi存期为i年,那么只有当第i(i ≤n-1)份资金按最佳存款策略存款到期后的本息和等于当年的奖学金数,并且第n份资金按最佳存款策略存款n年后的本息和等于原基金M与当年的奖学金数之和时,每年发放的奖学金才能达到最多.通过求解此模型,我们得到了基金的最佳存款策略,并求出了在n=10年,M=5000万元的情况下,基金的最佳使用方案.在可存款也可购买国库券时,采取一种转化方法,将国库券购买情况转化为相应年期的定期存款,结合问题(一)即可求得在n=10年,M=5000万元的情况下,基金的最佳使用方案;在第三年校庆时奖学金数额比其它年度多20%的问题的分析方法和模型的解决方法与前相同.     

Investigation of the Microstructure of Rolled Semi—Solid Steel

In this paper,spring steel-60Si2Mn and stainless steel-1Cr18Ni9Ti were rolled one pass in semi-solid state.The microstructural evolution during rolling of the steels with different solid fraction was investigated.The experimental results showed that the manner of liquid and solid phases flowing and deforming was different.During rolling,most of solid phases remained in the center of the rolled specimens,while liquid phase flowed to the edge,which resulted in the macrosegregation of liquid and solid phases.Only the amount of solid fraction reached a certain value,were the solid phases deformed and flattened.     

利用分形几何确定多孔介质的孔尺寸分布

提出了利用分形几何确定多孔介质孔尺寸分布的方法。考虑多孔介质中孔间的屏蔽，采用此方法得到的孔尺寸分布范围比采用平行孔模型宽，分别采用本方法和平行孔模型测定γ－Al2O3催化剂的孔尺寸分布，构造简单立方体三维网络模型模拟压汞过程，并将模拟曲线与γ－Al2O3压汞实验曲线比较，结果表明，采用本方法所得孔尺雨分布优于平行孔模型所得孔尺寸分布。     

崇礼东坪黄金公司缓倾斜薄矿体采空区综合治理

在采空区调查的基础上,以FLAC工程力学分析软件为手段,应用“诱导崩落和封闭采空区综合治理”理论,进行缓倾斜薄矿体采空区综合治理研究.该项研究与实践为缓薄矿体采空区综合治理提供了可供借鉴的经验,并为矿山创造了可观的经济效益.     

交流变频钻井泵试验台的研制

针对大功率、超高压（52MPa）钻井泵的试验问题，设计了采用交流变频控制技术，提高试验能力的试验台架。该试验台架体现了实用性、可操作性、高效节能、环保性；电气传动部分采用具有国际先进水平、成熟技术的交流变频调速系统，实现无级调速；机械传动部分采用单级双速变速箱，试验范围广；电控系统可完成对钻井泵各种参数在线监控和测定。     

Effects of Heat Treatment on the Transformation Temperature and the Microstructure of Ni-Ti-Nb Shape Memory Alloy

The effects of heat treatment on the phase transformation temperature and the microstructure of Ni-Ti-Nb alloy have been investigated by means of R-T method, TEM and EPMA. With the increase of annealing temperature, cooling rate and ageing temperature, the Ms temperature increases. TEM observations show no new precipitated phase was found in the B2 parent phase after heat treatment, but EPMA shows the content of Ni (or Ni/Ti ratio) in the B2 matrix changed. The main reason for the change of transformation temperature lies in the change of the matrix composition (or Ni/Ti ratio) with the variation of heat treatment procedure.     

异步交叉轧制能耗特性研究

对异步交叉轧制的能耗特性进行了分析与实验验证.研究表明,随交叉角增大,轧制能耗下降,当交叉角(θ)增至临界值(θcr)时,能耗最小,交叉角θ＞θcr后,能耗基本不变;随异步比增大,能耗亦下降,当异步比(i)增至临界值(icr)时,能耗最小, i＞icr后,能耗则上升,且θ愈大, icr亦愈大.即当交叉角为θcr且异步比亦为icr时,异步交叉轧制综合能耗最小.     

用熔融还原的方法从浸钒渣中提镓——碳饱和情况下的熔融还原过程

用通用旋转组合设计的方法得到了浸钒渣在饱和碳的熔融还原过程中镓的还原提取率与温度,时间及CaO的加入量关系的非线性数学模型。用非线性优化的方法并综合考虑Fe,Mn的回收,得到了最优的工艺条件及结果;用Langmuir—Knudsen方程推算了镓在铁液中的理论挥发量与时间的关系,与由本模型得到的关系式是一致的。     

Fe—Ga—O系平衡测定

在钼丝炉内氩气保护下，利用固体电解质定氧探头测定了含镓１．８７％～６．２１％范围内Ｆｅ－Ｇａ－Ｏ三元系平衡时的氧活度，通过处理得到镓在铁液中的标准溶解自由能等热力学参数与温度的关系。     

A new approach of formation navigation derived from multi-robots cooperative online FastSLAM

A new formation navigation approach derived from multi-robots cooperative online FastSLAM is proposed. In this approach,the leader and follower robots are defined.The posteriori estimation of the leader robot state is treated as a relative reference for all follower robots to correct their state priori estimations.The control volume of individual follower will be achieved from the results of the corrected estimation.All robots are observed as landmarks with known associations by the others and are considered in their landmarks updating.By the method,the errors of the robot posterior estimations are reduced and the formation is well kept.The simulation and physical experiment results show that the multi-robots relative localization accuracy is improved and the formation navigation control is more stable and efficient than normal leader-following strategy.The algorithm is easy in implementation.