丰满流域可能最大暴雨与可能最大洪水分析研究

依据丰满漉域的水文气象资料,计算丰满流域可能最大暴雨,推求白丰区间的可能最大洪水并进行成果合理性分析.     

Analytical modeling and experimental study of tensile strength of asphalt concrete composite at low temperatures

In this study, analytical modeling of the tensile strength of hot-mix asphalt (HMA) mixtures at low temperatures was developed. To do this, HMA mixtures were treated as a two-phase composite material with aggregates (coarse and fine) dispersed in an asphalt mastic matrix. A two-phase composite model, which was similar to Papanicolaou and Bakos's [J. Reinforced Plast. Compos. 11 (1992) 104] model with a particle embedded in an infinite matrix, was proposed. Unlike Papanicolaou and Bakos's model, an axial stress was introduced to the fiber end to consider the load transferred from the asphalt mastic the aggregate. Efforts were also made to consider the effect of aggregate gradation, asphalt mastic degradation, and interfacial damage between the aggregates and asphalt mastic matrix on the tensile strength of the HMA mixtures. Experimental investigations were conducted to validate the developed theoretical relations. A reasonable agreement was found between the predicted tensile strength and the experimental results at low temperatures. Parameters affecting the tensile strength of asphalt mixtures were discussed based on the calculated results.     

Formation and surface modification of self-assembled films with acrylated hyperbranched poly(ester-amine) as the outmost layer

An acrylated hyperbranched poly(ester-amine) (HPEA) synthesized from piperazine and trimethylolpropanetriacrylate at a molar ratio of 1:1.42 was used as the polycation to form self-assembled films by layer-by-layer dipping with poly(sodium-p-styrenesulfonate) as the polyanion. The surface morphology and hydrophilicity of the films with HPEA as the outmost layer were controlled by adjusting the solution pH of HPEA. Due to the existence of many acrylate groups, the films with HPEA as the outmost layer were further reacted with a series of reagents, including piperazine, piperidine, laurylamine and p-phenylenediamine. The surface reactions of the films depended on both the nature of the reagents and the morphology of the initial surface. In the presence of the strong basic amines, piperazine and piperidine, the films dissolved extensively into the solution. In the case of laurylamine, a modified film with an opaque appearance was obtained due to the crystallization of long alkyl chains. With the weak basic amine p-phenylenediamine as the reactant, the film was effectively modified without any change in the surface morphology.     

基于传感器信息的机器人精密装配作业分析

介绍了一个应用力传感器组成的智能机器人精密装配作业的宏／微操作系统，它能够完成一般凸形销孔零件沿任意方向的精密装配作业。     

穿孔顶头表面氧化膜浅析

分析了穿孔顶头表面氧化膜的形成过程、性质、作用、界面行为，以及对顶头使用寿命的影响。指出了提高该氧化膜耐久性的途径。     

Multistage amplifier topologies with nested Gm-Ccompensation

This paper presents a multistage amplifier for low-voltage applications (<2 V). The amplifier consists of simple (noncascode) low gain stages and is stabilized using a nested transconductance-capacitance compensation (NGCC) scheme. The resulting topology is similar to the well known nested Miller compensation (NMC) multistage amplifier, except that the proposed topology contains extra G _m feedforward stages which are used to enhance the amplifier performance. The NGCC simplifies the transfer function of the proposed multistage amplifier which, in turn, simplifies its stability conditions. A comparison between the NGCC and NMC shows that the NGCC has wider bandwidth and is easier to stabilize. A four-stage NGCC amplifier has been fabricated using a 2-μm CMOS process and is tested using a ±1.0 V power supply. A dc gain of 100 dB has been measured. A gain bandwidth product of 1 MHz with 58° of phase margin and power of 1.4 mW can be achieved. The op amp occupies an active area of 0.22 mm². Step response shows that the op amp is stable     

Boundary Constrained Swept Surfaces for Modelling and Animation

Due to their simplicity and intuitiveness, swept surfaces are widely used in many surface modelling applications. In this paper, we present a versatile swept surface technique called the boundary constrained swept surfaces. The most distinct feature is its ability to satisfy boundary constraints, including the shape and tangent conditions at the boundaries of a swept surface. This permits significantly varying surfaces to be both modelled and smoothly assembled, leading to the construction of complex objects. The representation, similar to an ordinary swept surface, is analytical in nature and thus it is light in storage cost and numerically very stable to compute. We also introduce a number of useful shape manipulation tools, such as sculpting forces, to deform a surface both locally and globally. In addition to being a complementary method to the mainstream surface modelling and deformation techniques, we have found it very effective in automatically rebuilding existing complex models. Model reconstruction is arguably one of the most laborious and expensive tasks in modelling complex animated characters. We demonstrate how our technique can be used to automate this process.     

废塑料改性沥青的性能研究

通过沥青基本性能测试、荧光显微镜观察研究了废塑料（PE）对改性沥青高温性能的影响及其机理,并通过对改性沥青混合料的马歇尔稳定度测试及对沥青混合料断口观察研究了混合料的强度及高温性能。结果表明：废PE达到一定剂量时,在沥青中形成网状结构,增强了改性沥青的高温性能；加入废PE后,沥青与矿料的结合强度提高,提高了沥青混合料的高温稳定性。     

在3．39μm波段甲烷吸收特性的测量与应用研究

报道了甲烷气体在３．３９μｍ波段吸收特性的研究结果，及其在３．３９μｍ波段多波长干涉测量中的应用。通过改变甲烷吸收室的充气参数，使激光器工作在双等光强工作点，并完成了绝对距离的干涉测量。     

Testing of the multi-application small light water reactor (MASLWR) passive safety systems

Experimental thermal hydraulic research has been conducted at Oregon State University for the purpose of assessing the performance of a new reactor design concept, the multi-application small light water reactor (MASLWR). The MASLWR is a pressurized light water reactor design with a net output of 35 MWe that uses natural circulation in both normal and transient operation. Due to its small size, portability and modularity, the MASLWR design is well suited to help fill the potential need for grid appropriate reactor designs for smaller electricity grids as may be found in developing or remote regions. The purpose of the OSU MASLWR test facility is to assess the operation of the MASLWR under normal full operating pressure and full temperature conditions and to assess the passive safety systems under transient conditions. The data generated by the testing program will be used to assess computer code calculations and to provide a better understanding of the thermal-hydraulic phenomena in the design of the MASLWR NSSS. During this testing program, four tests were conducted at the OSU MASLWR test facility. These tests included one design basis accident and one beyond design basis accident. During the performance of these tests, plant operations to include start up, normal operation and shut down evolutions were demonstrated successfully.