垂直流人工湿地净化机理及工程实践

结合工程实践——深圳石岩一期垂直流人工湿地,介绍了湿地的结构、组成、各部分功能、工艺特点、净化机理和脱氮除磷过程,根据石岩一期的运行情况,对人工湿地系统的污水净化效果、去除率、经济性进行了分析,研究表明,人工湿地系统是一种有效的污水处理技术并具有良好的发展前景.     

液态LPG直喷发动机混合气形成的数值解析

首先数值解析了缸内电控直喷汽油机的混合气形成过程,并且与光学纹影实验结果比较,验证了解析方法的可行性。在此基础上,分别考察了电控LPG直喷发动机曲面活塞顶燃烧室和凹坑型活塞顶燃烧室在部分负荷工况下混合气的形成过程。结果表明:在部分负荷下、压缩行程后期喷射时,由于缸内滚流的作用,两种不同形状活塞顶的燃烧室在接近压缩终了时,缸内混合气都能呈明显分层构造,即在火花塞附近聚集了较浓的混合气,而离火花塞较远处则是较稀的混合气,整个燃烧室的空燃比达到40∶1。     

EVA/Al_2O_3纳米复合材料的结构与性能

以纳米A l2O3为增强材料,制备了EVA/A l2O3纳米复合材料,并采用FESEM、FT-NIR、SEM等测试手段表征纳米A l2O3微粒在EVA基体中的分散性与结构,研究了纳米A l2O3的质量分数对纳米复合材料力学性能的影响。结果表明:A l2O3微粒以20 nm左右的粒径分散于EVA基体中,并与EVA形成化学键合结构,复合材料的断裂机理发生变化。填充质量分数为0.5%的纳米A l2O3微粒时,拉伸强度提高13.0%;当加入的纳米A l2O3的质量分数为1%时,断裂伸长率可提高13.3%。     

2-苯并噻唑偶氮-7-(4-硝基苯偶氮)-1,8-二羟基萘-3,6- 二磺酸的合成及用于铁和钛同时分光光度测定

合成了一种新的不对称双偶氮变色酸类试剂 2 苯并噻唑偶氮 7 ( 4 硝基苯偶氮 ) 1 ,8 二羟基萘 3,6-二磺酸。研究了试剂的结构和试剂的光度性质 ,并用偏最小二乘法 (PLS)不经分离同时分光光度测定了合成试样和铝合金试样中的微量Fe 和Ti 。     

A memory-based model for planning target reach postures in the presence of obstructions

Existing posture prediction and motion simulation models generally lack the capability of simulating human obstruction avoidance during target reach. This compromises the utility of digital human models for ergonomics, as many design problems involve interactions between humans and obstructions. To address this problem, this paper presents a novel memory-based posture planning (MBPP) model, which plans reach postures that avoid obstructions. In this model, the task space is partitioned into small regions called cells. For a given human figure, each cell is linked to a memory that stores various alternative postures for reaching the cell. When a posture planning problem is given in terms of a target and an obstruction configuration, the model examines postures belonging to the relevant cell, selects collision-free ones and modifies them to exactly meet the hand target acquisition constraint. Simulation results showed that the MBPP model is capable of rapidly and robustly planning reach postures for various scenarios.     

Receptive field structures for recognition

Localized operators, like Gabor wavelets and difference-of-gaussian filters, are considered useful tools for image representation. This is due to their ability to form a sparse code that can serve as a basis set for high-fidelity reconstruction of natural images. However, for many visual tasks, the more appropriate criterion of representational efficacy is recognition rather than reconstruction. It is unclear whether simple local features provide the stability necessary to subserve robust recognition of complex objects. In this article, we search the space of two-lobed differential operators for those that constitute a good representational code under recognition and discrimination criteria. We find that a novel operator, which we call the dissociated dipole, displays useful properties in this regard. We describe simple computational experiments to assess the merits of such dipoles relative to the more traditional local operators. The results suggest that nonlocal operators constitute a vocabulary that is stable across a range of image transformations.     

基于MapX的高速公路动态拓扑结构的构建

最优路径分析是地理信息系统(GIS,Geographic Information System)网络分析的基础,而道路网络拓扑结构的构建又是最优路径分析的关键.结合高速公路网和MapX组件的特点,将MapX控件与Visual C++ 6.0开发平台相结合,采用数据结构中的邻接表来表示高速公路网络的拓扑结构.仿真结果表明,对高速公路电子地图中任意选定的某条道路或某些区域,系统都能形成所选区域中道路之间的拓扑关系,并将提取出的相关道路的路网信息自动存储到数据库中,从而为后续的道路交通仿真及事故救援时进行最优路径搜索提供必要的信息.     

基于遗传算法的协作学习自动分组

分组直接影响协作学习的效果,采用异质分组,对学生的学习能力、学生特性和性别进行特征量化可得到一个7元组,本文提出一种基于遗传算法的协作学习自动分组策略,对学生7元组特征进行个体编码,设置适应度函数进行遗传操作,为实现协作学习的自动分组提高了效率和可靠性。     

Physical modeling with orthotropic material based on harmonic fields

Although it is well known that human bone tissues have obvious orthotropic material properties, most works in the physical modeling field adopted oversimplified isotropic or approximated transversely isotropic elasticity due to the simplicity. This paper presents a convenient methodology based on harmonic fields, to construct volumetric finite element mesh integrated with complete orthotropic material. The basic idea is taking advantage of the fact that the longitudinal axis direction indicated by the shape configuration of most bone tissues is compatible with the trajectory of the maximum material stiffness. First, surface harmonic fields of the longitudinal axis direction for individual bone models were generated, whose scalar distribution pattern tends to conform very well to the object shape. The scalar iso-contours were extracted and sampled adaptively to construct volumetric meshes of high quality. Following, the surface harmonic fields were expanded over the whole volumetric domain to create longitudinal and radial volumetric harmonic fields, from which the gradient vector fields were calculated and employed as the orthotropic principal axes vector fields. Contrastive finite element analyses demonstrated that elastic orthotropy has significant effect on simulating stresses and strains, including the value as well as distribution pattern, which underlines the relevance of our orthotropic modeling scheme.     

ProteinParser--a community based tool for the generation of a detailed protein consensus and FASTA output

Comparison of bioinformatic data is a common application in the life sciences and beyond. In this communication, a novel Java based software tool, ProteinParser, is outlined. This software tool calculates a detailed consensus, or most common, amino acid at a given position in an aligned protein set, whilst also generating a full consensus protein FASTA output. A second application of this software tool, computing a consensus amino acid given a tolerance threshold, is also demonstrated. The phytase and the common bacterial beta-lactamase proteins are analysed as 'proof of concept' examples. Consensus proteins, as generated by ProteinParser, are regularly utilised in the selection of residues for protein stabilisation mutagenesis; however, this widely applicable software tool will find many alternative applications in areas such as protein homology modelling.