IPv6地址路由机制研究综述

IPv6协议是在IPv4的基础上发展起来为了解决现有网络问题的协议。其地址路由机制是下一代网络运行的基础。该文介绍了IPv6协议现有的地址路由的一些机制和标准,在这些机制的基础上总结了现今IPv6路由的热点问题,并参考了国内外的一些研究文档,对这些问题的一些解决方案进行了概括描述和分析。最后对于目前研究的方向和解决方法进行归纳。     

镁合金及镁基复合材料阻尼性能研究进展

简要介绍了纯镁、镁合金及镁基复合材料的位错型阻尼机理,叙述了温度、合金成分、组织结构和微观缺陷(包括晶界相界)以及热处理等因素对镁合金阻尼性能的影响.镁基复合材料较镁合金有较高的阻尼性能,是由于增加了多种阻尼机制的结果,其中最重要的是塑性区阻尼、位错密度的增大、界面滑移阻尼等.     

人工神经网络在建筑物物理力学参数识别中的应用

基于神经网络的BP算法,建立了识别建筑物物理力学参数的数值方法.在经典的BP算法中,网络中的权值的确定是将权值的计算修正过程描述为网络的训练过程,其中迭代步长由经验选定,常常造成收敛速度慢,并且收敛速度与初始权值的选择有关以及引起振荡等问题.在网络的训练过程中采用改进的BP算法,通过对学习算子的优化搜索,大大提高了网络的收敛速度,解决了BP算法迭代过程中目标函数的震荡问题.数值计算表明,所提出的改进的BP算法进行建筑结构物理力学参数识别的收敛速度和识别精度都得到了提高.     

网络化制造中加工过程仿真的研究

分析了加工过程仿真的工业需求 ,提出加工过程建模和仿真的关键技术问题 ,并实现一种铣削力在网络环境中的仿真     

Three classes of binary linear codes with good parameters

Three classes of linear codes with good parameters are constructed in this paper. The length, dimension and minimum distance for each class of linear codes are also investigated by means of the well-known Kloosterman sums over finite fields. It is interesting to note that the constructed three classes of linear codes possess good parameters and some of them are shown to be optimal.     

1200kt/a乙烯改扩建工程管网改造项目方案探讨

1200kt/a乙烯改扩建工程是大庆石化公司"十一五"发展的重点工程。文中以该工程的工艺及热力管网改造项目为例,从工程概况、材料计划、施工方案编制、过程经营、成本控制、风险防范等方面,探讨了管网改造项目的实施方案。     

反渗透装置处理炼油污水的优化运行

阐述了在土地勘测定界测量中,为了提高工作效率,减少在生产中出现的错误,利用VB2005结合.NET API对AutoCAD进行了二次开发。在土地分类标注文字中,把土地类别和面积分别加入到文字的扩展数据中,然后在面积统计中再提取文字中的扩展数据进行计算并输出至表格,实现了土地利用分类的标注和面积统计的自动化。     

Isolation and identification of high pressure‐resistant bacteria naturally contaminating strawberry pulp

The inactivation of bacteria naturally present in strawberry pulp was investigated after high hydrostatic pressure (HHP) treatment at pressure levels up to 600 MPa at 25 °C for 5 ~ 25 min. Five strains of pressure‐resistant bacteria designated as A, B, C, D and E were isolated and identified. The five strains were gram‐positive, spore‐forming, rods or rod in chains. Growth of the strains was observed at 30 ~ 45 °C, and strain B also grew well at 55 °C. They could produce acid from glucose and were catalase‐positive. Analysis of 16S rRNA gene sequences showed that the five strains belonged to the genus Bacillus. Strain A and D exhibited the greatest 16S rRNA gene sequence similarity of 99% with B. licheniformis and B. firmus, respectively. By combination of phenotypic characteristics and 16S rRNA gene sequences, strain C was B. mycoides and E was B. pumilus. On the basis of physiological and biochemical characteristics, gyrB gene sequences analysis and whole‐cell fatty acids analysis, strain B was B. amyloliquefaciens. Further studies showed that strain B (B. amyloliquefaciens) exhibited the highest pressure resistance, and it was reduced by 4.62‐log after treatment at 600 MPa for 25 min at 25 °C as the most effective observed inactivation.     

面向任务口语理解研究现状综述

口语理解是对话系统重要的功能模块，语义槽填充和意图识别是面向任务口语理解的两个关键子任务。近年来，联合识别方法已经成为解决口语理解中语义槽填充和意图识别任务的主流方法，介绍两个任务由独立建模到联合建模的方法，重点介绍基于深度神经网络的语义槽填充和意图识别联合建模方法，并总结了目前存在的问题以及未来的发展趋势。     

Discovery of Dual ETA/ETB Receptor Antagonists from Traditional Chinese Herbs through in Silico and in Vitro Screening

Endothelin-1 receptors (ETAR and ETBR) act as a pivotal regulator in the biological effects of ET-1 and represent a potential drug target for the treatment of multiple cardiovascular diseases. The purpose of the study is to discover dual ETA/ETB receptor antagonists from traditional Chinese herbs. Ligand- and structure-based virtual screening was performed to screen an in-house database of traditional Chinese herbs, followed by a series of in vitro bioassay evaluation. Aristolochic acid A (AAA) was first confirmed to be a dual ETA/ETB receptor antagonist based intracellular calcium influx assay and impedance-based assay. Dose-response curves showed that AAA can block both ETAR and ETBR with IC₅₀ of 7.91 and 7.40 μM, respectively. Target specificity and cytotoxicity bioassay proved that AAA is a selective dual ETA/ETB receptor antagonist and has no significant cytotoxicity on HEK293/ETAR and HEK293/ETBR cells within 24 h. It is a feasible and effective approach to discover bioactive compounds from traditional Chinese herbs using in silico screening combined with in vitro bioassay evaluation. The structural characteristic of AAA for its activity was especially interpreted, which could provide valuable reference for the further structural modification of AAA.