基于磁致伸缩位移传感器的高炮浮动参数测试系统

针对高炮射击时自动机运动速度快、冲击加速度大和测试环境恶劣等情况,结合浮动参数的测试要求,采用磁致伸缩位移传感器,设计了一种采样精度高、功能多且操作简便的测试系统。系统由硬件和软件组成,硬件采用单片机多CPU控制技术和宏控带锁非易失性数据存储技术,实现了多路位移数据的自动同步采集和自动检测起始零位。软件根据采集的位移数据,利用单调曲线的纵向关联性实现了浮动参数的计算,并根据需要进行参数和曲线的显示、保存或打印。实弹测试试验表明,系统能够满足高炮浮动参数的测试要求。

某自行高炮浮动参数监测系统的设计与实现

为了能够实时掌握自行高炮自动机性能,提高装备的可靠性,利用无线传感器网络技术,设计并建立了自行高炮浮动参数监测系统。该监测系统利用磁致伸缩位移传感器,实现了后坐位移的精确测量;设计了一种具有高速采集和片上处理功能的无线传感器网络节点,实现了数据的采集、储存与无线传输;开发了上位机软件,能够根据回传数据,完成后坐曲线的显示和浮动参数的自动提取。实弹测试试验表明,该监测系统能够基本满足自行高炮浮动参数在线监测的要求。

首发浮动的高初速榴弹机枪发射性能研究

为研究采用首发浮动技术的榴弹机枪(GMG)的动力学特性,建立GMG刚柔耦合动力学模型,并进行了20连发动力学计算。通过动力响应研究了浮动参数对射击密集度的影响。采用外弹道理论计算了20连发射击密集度,并与实验值进行比较,对动力学模型的准确性进行了验证。研究了浮动参数对武器架座力及射击密集度的影响规律。研究结果表明:建立的仿真计算模型可以有效预测GMG射弹散布,并可通过合理匹配浮动参数达到提高武器射击密集度、降低武器后坐力的目的。

基于反馈线性化/LQR方法的高超声速飞行器姿控系统设计

进行了吸气式乘波体高超声速飞行器建模与姿态控制系统设计。首先基于拟合气动参数,建立了高超声速飞行器纵向动力学数学模型;然后针对模型参数不确定性情况,在对系统进行反馈线性化基础上,借助状态转换和一阶泰勒级数展开,建立了不确定部分的线性化模型,并设计了LQR控制器参数。最后仿真结果表明,当模型参数浮动的情况下,本文设计的高超声速飞行控制系统,能很好地实现速度与弹道倾角参考指令跟踪。

Effect of surface dissolution on kinetic parameters in flotation of ilmenite from different gangue minerals

The effects of acid surface dissolution on the flotation kinetics of ilmenite(IL)and its common accompanied gangue minerals including olivine-pyroxene(Ol-Px),tremolite-clinochlore(Tr-Cch)and quartz were investigated.The results show that through the surface dissolution the adsorption rate constant for ilmenite increases from 5.272 to 8.441 mol/(g·min)while it decreases for Ol-Px,Tr-Cch and quartz from 6.332,7.309 and 7.774 mol/(g·min)to 5.034,6.223 and 7.371 mol/(g·min),respectively.Also,the flotation experiments on a binary mixture of minerals indicate that after surface dissolution the values of modified rate constant for ilmenite flotation from Ol-Px,Tr-Cch and quartz are enhanced from 36.15,36.52 and 47.86 min-1 to 41.72,45.78 and 56.24 min-1,respectively.This results in the improvement of kinetic selectivity index(SI)in the separation of treated ilmenite from gangue minerals.As evidenced by ICP-MS analysis,the decrease of kinetic parameters for gangue minerals can be due to the removal of Fe^2+,Ca^2+and Mg^2+ions from their surfaces,which results in the lack of enough active sites to interact with collector species.As confirmed by contact angle measurements,this prevents the formation of a stable hydrophobic layer on the minerals surfaces for creating stable attachments between minerals and bubbles.Generally,the improvement of ilmenite flotation kinetics has a negative correlation with the iron content in its accompanied gangue minerals.

Investigating the first-order flotation kinetics models for Sarcheshmeh copper sulfide ore

This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stage,influence of pH,solid concentration,water chemistry and the amount of collector dosage were investigated on kinetics parameters including flotation rate constant and ultimate recovery.The results indicated that that perfectly mixed reactor model and Kelsall model gave the best and the weakest fit to the experimental data,respectively.It was observed that flotation rate constant and ultimate recovery were strongly affected by chemical factors investigated especially water quality.The flotation rate constant decreased with increasing the solids content,while ultimate recovery increased to certain value and thereafter reduced.It was also found that the most values of flotation rate constant and ultimate recovery obtained in dosage of collector are 30 and 40 g/t,respectively.

Zooplankton community of Keibul Lamjao National Park (KLNP) Manipur, India in relation to the physico-chemical variables of the water

Keibul Lamjao National Park （KLNP）, a floating park in Loktak Lake, Manipur （India） was studied from Winter （WIN） to Post Monsoon （POM） for its zooplankton composition and some selected water parameters. The resultant data were subjected to multivariate techniques---Principal Component Analysis （PCA） and Canonical Correspondence Analysis （CCA）. Analyses of water parameters with PCA revealed that the first PC axis （PC 1） accounts for maximum variance in the seasonal data, explaining a variability of 91%. The PCA revealed that the seasonal variability in water parameters was due to the wet and dry cycle of seasons and the stations were distinguished on the basis of transparency and turbidity. Zooplankton abundance was dominated by copepods followed by cladocerans. Temporally, abundance of copepods reached a maximum during Post-monsoon （POM） （3 880 ind./L）. Spatially, $6 was found to be most abundant of the other stations in zooplankton. Copepodites and nauplii larvae were the major components of zooplankton. The Rotifera were the least abundant among the three zooplankton groups. Brachionus formed the major component of Rotifera zooplankton at all the stations during the study period. In the Cladocera, Macrothrix was present during all the four seasons, while Pleuroxus, Oxyurella, Kurzia and, Diaphanosoma were rare. The CCA shows that maximal temporal variability in zooplankton abundance was explained by temperature and rainfall. ANOVA revealed no significant difference in mean zooplankton abundance among the seasons, but there was a statistically significant difference among the sites.

Temperature and Process Variations Aware Dual Threshold Voltage Footed Domino Circuits Leakage Management

Considering the effect of temperature and process variations, the inputs and clock signals combination sleep state dependent leakage current characteristics is analyzed and the optimal sleep state is examined in sub-65nm dual threshold voltage （V1） footed domino circuits. HSPICE simulations based on 65nm and 45nm BSIM4 models show that the proposed CLIL state （the clock signal and inputs are all low） is the optimal state to reduce the leakage current of the high fan-in footed domino circuits at high temperature and almost all footed domino circuits at room temperature, as compared to the conventional CHIL state （the clock signal is high and inputs are all low） and the CHIH state （the clock signal and inputs are all high）. Further, the influence of the process variations on the leakage current characteristics of the dual V1 footed domino circuits is evaluated. At last, temperature and process variation aware new low leakage current setup guidelines are provided.