醋酸装置火炬头的低噪无烟化改造

分析了醋酸厂低压甲醇羰基化生产醋酸装置火炬头运行噪音过高的原因,认为运行噪音过高主要是由于助燃蒸汽喷射噪音所引起;比较了几种降低噪音方法的可行性;改造采用火炬头中下部的蒸汽引射空气喷嘴注入方式的方法代替火炬头顶部简单的蒸汽喷射,并加设高效盆式消声器.改造后距火炬中心80 m处的噪音强度从原来的105dB(A)降低至79 dB(A),取得了良好的效果.     

Some characteristics of X-ray imaging for energy region of over 100 keV using plastic scintillation fiber array

In this work, characteristics of using PSFs （plastic scintillation fibers） coupled with CCD （charge-coupled devices ） to build area detectors for high energy X-ray imaging are studied with a Monte Carlo simulation, which cover an energy range of a few hundred keV to about 20 MeV. It was found that the efficiency of PSF in detecting X-ray with energy above a few hundred keV is low. We can use large incident flux to increase the output signal to noise ratio （SNR）. The performance can also be improved by coating PSF with X-ray absorption layers and the MTF of the system is presented. By optimizing the absorption layer thickness, the crosstalk of the area detector built with PSF decreases.     

随机微分方程解的不合流性

研究了一维Ｉｔｏ型随机微分方程,在相当弱的条件下,当扩散系数非退化时,证明了方程强解的不合流性。     

利用建筑设计减少纺织厂噪音

分析了纺织厂噪声对劳动环境的危害程度，从建筑学的角度论述了内吸外隔的治理手段。     

一种透射式低温光学系统的设计与验证

由于能够减小系统自身的热噪声和提高系统信噪比,低温光学是实现高灵敏度红外探测的必要手段。提出了一种将脉冲管制冷机用作冷源的透射式低温光学系统。这种新型低温光学系统可用于体积和重量受限而又需要进行高灵敏度红外探测的场合。从光学设计、光机结构设计和内部热噪声分析等方面说明了透射式低温光学系统的设计过程。搭建了用于对脉冲管制冷机冷却光学系统的可行性进行验证的试验系统,并从系统内部热噪声的角度对低温光学的有效性进行了验证。实验结果表明,经过3 h,透镜温度由300 K降至设计温度150 K,继续降温则可达到最低温度105 K。测试过程中,透镜保持完好,验证了将脉冲管制冷机用作冷源的可行性。用黑体和320×256元碲镉汞探测器对光学系统自身的热噪声进行了测试。结果表明,当光学系统的温度从300 K降至215 K时,其自身热辐射减少了75%。这与理论分析结果一致,验证了低温光学降噪的有效性。     

选煤厂溜槽减振降噪的设计与应用

通过对选煤厂溜槽噪声的分析,介绍了几种在选煤生产中常用的溜槽减振降噪方法,并阐述了各方法的减振降噪原理与特点,为选煤生产中溜槽噪声的治理提供了借鉴。     

基于随机LQ控制的一类投资组合优化策略

将随机LQ控制模型推广到系统状态为带有马尔科夫调制参数的跳跃-扩散过程的随机LQ控制模型,采用倒向随机微分方程得到最优反馈控制,然后用来处理借贷利率不等条件下的投资组合问题.将原始问题转化为随机LQ最优控制问题后,引入跳跃-扩散的随机Riccati方程,应用随机变分法求得问题的最优反馈控制策略.     

高速列车车内声品质优化仿真研究

随着高速列车运行速度的不断提高,车内噪声问题对乘坐舒适性的影响越来越显著.为了抑制高速列车车内噪声的影响,基于改进的能量有限元方法,建立高速列车车内噪声的预测模型,并验证模型的准确性.基于预测模型,结合Zwicker响度模型、Zwicker尖锐度模型和Aures粗糙度模型,研究轮轨噪声激励的优化对车内声品质的影响.结果...     

Deciphering and handling uncertainty in shale gas supply chain design and optimization: Novel modeling framework and computationally efficient solution algorithm

The optimal design and operations of shale gas supply chains under uncertainty of estimated ultimate recovery (EUR) is addressed. A two‐stage stochastic mixed‐integer linear fractional programming (SMILFP) model is developed to optimize the levelized cost of energy generated from shale gas. In this model, both design and planning decisions are considered with respect to shale well drilling, shale gas production, processing, multiple end‐uses, and transportation. To reduce the model size and number of scenarios, we apply a sample average approximation method to generate scenarios based on the real‐world EUR data. In addition, a novel solution algorithm integrating the parametric approach and the L‐shaped method is proposed for solving the resulting SMILFP problem within a reasonable computational time. The proposed model and algorithm are illustrated through a case study based on the Marcellus shale play, and a deterministic model is considered for comparison. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3739–3755, 2015     

车门内饰板优化分析及模具设计

利用CAE分析软件Moldex3D先找出整个设计是否存在缺陷,为了增加优化效率,采用田口实验设计法规划控制因子与配置。L9(34)直交表来求得成型条件的最佳化参数组别,观察结果并找出最佳成型条件,以降低成型后所发生的体积收缩率以及翘曲位移量。由S/N因子反应表可看出对于Z轴变形量在塑料温度209℃、保压时间11.025 s、冷却时间17.85 s时较优良。Z轴的翘曲从1.64 mm降低到1.04 mm,整体改善了36.5%,最终根据优化结果进行了模具设计。