Rapid Prototyping and Manufacturing Technology: Principle,Representative Technics,Applications, and Development Trends

The rapid prototyping and manufacturing technology (RPM), is an integration of many different disciplines. It is based on an advanced dispersed-accumulated forming principle and originated from 1980s. It generates an entity by first forming a series of layers according to the dispersed section information of the digital model, and then piling the formed layers sequentially together. It is capable of forming parts with complicated structures and non-homogeneous materials. Traditional RPM techniques are mainly used as prototypes in product invention process, such as stereolithography, three-dimensional printing, laminated object manufacturing, and fused deposition modeling. Later, with the progress of material and enabling technology, many new RPM techniques emerged out and have been already applied in the fields such as rapid tooling/moulding, direct formed usable part, nano-/micro-RPM, and biomanufacturing. This high flexible digital manufacturing method has a likely ability to become an almighty forming technology.     

Sikkema-Kantorovitch算子在B_α空间的逼近

研究了Sikkema－kantorovitch算子在Bα空间的逼近估计．     

时间延缓的动力学计算

从动力学的观点计算相对论效应中的时间延缓，提出一种关于时间延缓的因果型说明     

运用弦振动法测大型构件的应力

介绍了一种新的测量构件应力的方法，论述了振弦作为敏感元件的工作原理，并提出了缩放倍数的概念；最后用实例验证了这一方法的可行性。     

甲胺磷原油中硫酸二甲酯的正相高效液相色谱分析

采用 Ｃ１８ 柱，示差折光检测器，以７０３０（ 体积比） 正己烷 异丙醇为流动相的正相高效液相色谱对甲胺磷原油中的硫酸二甲酯进行了分析，方法准确，快速，其平均回收率为９８ ．４ ％ ，相对标准偏差小于０ ．５ ％ ．     

深冷处理对高速钢高低温力学性能的影响研究

研究了深冷处理和未深冷处理的试样在室温及高温下的力学性能 .结果表明 ,深冷处理试样的力学性能明显提高 ;深冷处理和未深冷处理试样的磨损表面形貌和垂直截面形貌有显著差异 ,说明它们有不同的磨损规律 ;通过X 射线衍射还发现 ,深冷处理可使马氏体轴比和碳含量下降 ,促使新相碳化物MC析出 .     

二阶PLL特性参量的一种新测试方法

通常测量二阶锁相环(PLL) 的自然角频ωn 和阻尼系数ζ时,需要分别测量环路直流总增益和滤波器的时间常数等有关参量,此方法繁琐且误差较大.本文讨论一种通过输入小频偏的调频信号,可以方便、且较准确地测出理想二阶PLL的ωn 和ζ的实际值.该方法同样适用于非理想二阶环,以及由相位超前无源比例积分器构成的二阶环.     

Consistent Algorithm for Multi-value Constraint with Continuous Variables

Mature algorithms for the Constraint Satisfaction Problem (CSP) of binary constraint with discrete variables have already been obtained for the application. For the instance of multi-value constraint with continuous variables, the approach will be quite different and the difficulty of settling will aggrandize a lot. This paper presents the algorithm for realizing global consistency of continuous variable. And this algorithm can be applied to multi-value constraint.     

SF6的单取代和二取代物中^2JFF的半经验计算

运用最大键级杂化轨道这一计算方法，计算并拟合得到单取代和二取代的ＳＦ６衍生物中＾２ＪＦＦ的具体计算公式，由新公式得到的计算值与实验值基本吻合。     

Constrained oscillation of a bubble subjected to shock wave in microvessel

A three-phase coupled model of the gas–liquid–solid oscillation system is established to analyze the oscillation characteristics of a bubble inside a micro blood vessel with various radii and its shape changes with different interface boundaries. The results show that unlike the spherical symmetric oscillation in an unbounded fluid, the oscillating bubble has significant asymmetric characteristics under the constraint of a flexible microvessel, especially while its radius reduces to the same order of magnitude as that of the bubble. Moreover, the variation of microbubble motion, whether the geometric shape or oscillation feature, exhibits obvious differences in the micro blood vessel compared with the rigid wall. The reasons behind these phenomena are analyzed in this paper. The conclusions have significant importance in the understanding of the mechanism of microvessel injury in ultrasound therapy.