排毒完全手册

人体需要排毒的原因若胆固醇过高,没有及时排出体外,容易沉积在血管壁上,使血管变窄,导致高血压和动脉硬化等疾病。宿便是人体肠道毒素根源。被重吸收的毒素会重新侵入身体,降低人体免疫力,甚至长期便秘的女性经常会长痘痘。按照自然规律,夏季本是排毒的最佳时机,因为天气炎热,人体会通过大量出汗的方式来排出一年来堆积的毒素。但是现在生活带给我们空调、冷饮、电风扇,使得我们在都市生活中成为"不出汗一族"。没有办法通过自然手段排毒,那么只能自己动手,丰衣足食,用人工手段来排毒了。     

New hard X-rays sources at 38° declination

We report the detection of three new hard X-Rays sources emitting in the range 15 – 150 KeV. Their observation was carried out by means of a balloon borne payload, consisting of two large area high spectral resolution Multiwire Spectroscopic Proportional Counters.     

Effect of Forbush decreases of cosmic ray flux on ozone at higher middle latitudes

The Forbush decreases of cosmic ray flux occur prevailingly together with geomagnetic storms, because these phenomena have a similar origin in solar/interplanetary processes. To study the effects of large Forbush decreases on total ozone at middle latitudes, we use the TOMS total ozone data along latitudinal circles 40°N and 50°N. The effects of Forbush decreases are found to occur or to be non-measurable under the same conditions as those of geomagnetic storms: certain effect occurs only at 50°N (not 40°N), in winter, under conditions of high solar activity and the east phase of the QBO. However, the effects of the analyzed Forbush decreases are weaker than the effects of strong geomagnetic storms.     

用有限元显式算法解具有烧蚀动边界的传热问题

本文借助于运动坐标系用显式有限元算法求解烧蚀动边界的传热问题。通过坐标变换,在变换平面内确定固定的有限元结点,物理平面内对应的结点随边界的烧蚀而运动。在线性插值函数模式下温度的时间导数在三角形单元中处处相等的假设下导出有限元方程的显式计算格式。对横观各向同性材料的端头帽在再入飞行中的烧蚀和瞬时温度场的计算结果与用有限差分法计算的结果相互吻合。     

Integrated track splitting filter--efficient multi-scan single target tracking in clutter

A fully automatic tracking algorithm must be able to deal with an unknown number of targets, unknown target initiation and termination times, false measurements and possibly time-varying target trajectory behaviour. An efficient algorithm for tracking in this environment is presented here. This approach makes use of estimates of the probability of target existence, which is an integral part of the algorithm. This allows for the efficient generation and management of possible target hypotheses, yielding an algorithm with performance that matches what can be obtained by multiple hypothesis tracking-based approaches, but at a significantly lower computational cost. This paper considers only the single target case for clarity. The extension to multiple targets is easily incorporated into this framework. Simulation studies are given that show the effectiveness of this approach in the presence of heavy and nonuniform clutter when tracking a target in an environment of low probability of detection and in an environment where the target performs violent manoeuvres.     

双层旋转锥形液膜一次破碎特性数值研究

为了全面加深对锥形液膜一次破碎机理的认识,对双层锥形液膜的雾化过程进行了数值模拟,重点研究了压降和同轴旋转空气对双层液膜宏观形态、液膜破碎模式、液膜破碎长度和喷雾锥角等液膜一次破碎特性的影响。数值计算的喷雾场宏观形态与试验结果接近,喷雾锥角和索特尔平均直径的计算最大误差分别为4.9%、7.4%。研究表明：同轴旋转空气参与雾化会改变喷雾场的整体形态;增大压降和空气速度会改变液膜的破碎模式和主导表面波模式;双层液膜的合并会在液膜表面产生剧烈的表面波动,同时会略微增大液膜的喷雾锥角;液膜的破碎长度会随着压降和同轴旋转空气轴向速度的增大而减小。该研究有助于进一步研究双层液膜一次破碎的机理,从而指导对双路离心式喷嘴的雾化认识。     

表贴式永磁电机碳纤维护套转子强度及过盈量分析

针对表贴式永磁电机转子在高速高温状态下转子强度计算问题,提出了考虑磁钢分块结构的转子模型。基于厚壁圆筒理论推导了转子强度计算的解析解,分别计算出碳纤维护套及磁钢的切向应力和径向应力;基于有限元法分析了多种工况下的转子强度,在高速及高温工况下转子所受应力均会增加;对比解析分析结果表明,有限元法及解析法均能准确计算碳纤维护套应力,而磁钢却受到边缘效应的影响,磁钢边缘应力增大,解析分析难以进行精准计算;基于有限元法分析护套与磁钢过盈量,优化了转子结构,提出了过盈量的最优范围。     

空间目标RCS序列的分形分析

空间运动目标雷达散射截面(RCS)序列为非平稳时间序列, 常用时间序列分析方法很难对其进行分析和特征提取。针对部分空间运动目标 RCS序列的变化规律, 首次引入了分数布朗运动模型对其 RCS序列进行分析和特征提取。实测数据处理结果表明,其RCS序列具有分形特性, 其分形维可作为空间目标识别的有效特征。     

浅谈PON网络的工程测试方法

PON是将光网络单元(ONU)安装在住家用户或企业用户处,是最靠近用户的光接入网应用类型。本文介绍了PON网络的相关测试,包括PON网络的测试仪器选用、测试要求、测试方法以及注意事项。