基于UTOPIA接口的数据采集设计与实现

通过对信元的深入分析 ,提出基于ATM技术的UTOPIA接口的IP数据包的提取方法。用FPGA实现ATM层的数据分装与重组 ,可大大提高转换速度 ,然后通过对CPCS -PDU的分析采用软件提取IP数据包 ,最后给出了基于UTOPIA接口的信元提取的仿真结果。     

TD-PRS终端的子网相关会聚协议

阐述了基于TD-SCDMA分组数据标准(TD-PRS)的子网相关会聚协议(SNDCP)的功能和目的，并对SNDCP的应用进行了分析，提出了SNDCP层的一种实现方案，最后给出了协议数据单元(PDU)的分段和重组的仿真算法。结果表明，此方案是可以实现该协议的。     

The microtubule aster formation and its role in nuclear envelope assembly around the sperm chromatin in<Emphasis Type="Italic">Xenopus</Emphasis> egg extracts

Nuclear envelope separates cell genome from cyto-plasm in eucaryotic cells and plays a pivotal role in the cell life. The nuclear envelope is composed of two jointed membranes, the inner membrane and the out membrane, embedded the nuclear pore complexes. The out membrane is continuous with the endoplasmic reticulum (ER). The ARTICLES inner membrane faces to and connects with the chromatin through the nuclear lamina, an intermediate filamentous network thought to play a structural role for…     

Atomic force microscopy observation on nuclear reassembly in a cell-free system

Cell-free system is interesting and useful for studying nuclear assembly in mitosis. Atomic force microscopy (AFM), which is a simple way for imaging fixed reassemble nuclei with high resolution, has not been used in the cell-free system. In this paper, we put forward an air-drying sample preparation for AFM. Using AFM, we observed nuclear reassembly process within 100 nm resolution in a cell-free system. As a result, we found that the images were artifact-free, and with higher resolution compared with fluorescent optical microscope images. Furthermore, the morphology of membrane vesicles was obtained dearly, and a dynamic change of morphology during the vesides‘‘ approaching to nuclear envelope was also observed, which is enlightened to understand the mechanism of nuclear envelope assembly.     

面向维修的机械系统可靠度预测与仿真研究

机电产品在服役期间因零件失效而产生故障,重组维修破坏了原有的系统可靠性模型,因而需要对设备可靠性问题重新进行研究和评价。基于机电系统中零件的失效时间分布密度函数,研究了在重组维护过程中机电系统服役期间零件年龄结构的分布规律,发展了机电系统可靠性数学模型。通过仿真研究,探讨了系统服役期间年龄结构、可靠度和失效率的发展规律,定量地研究了失效时间分布密度函数的参数对系统可靠度的影响。这对于评估机械系统的可靠性和全生命周期的失效率,制定合理的维修策略具有重要意义。     

A preliminary study on functional domains of small heat shock protein Hsp16.3

Hsp16.3, the small heat shock protein (sHSP) from Mycobacterium tuberculosis, was originally identified as an immunodominant antigen,which possesses three functional domains typical of sHSP family, namely the N-terminal hydrophobic region, α-crystallin domain and a short non-conserved C-terminal extension.To further understand the functional assignment of these independent regions, the three functional domains of Hsp16.3 were defined and the two N- or C-terminal truncated Hsp16.3 remnants were successfully cloned, expressed and purified.In the far and near circular dichroism analysis, the results showed that these remnants expressed similar secondary and tertiary structures to that of wild-type protein.During the reassembly of wild-type nonamer, the C-terminal truncated remnant could interact with the wild-type protein to form hetero-oligomers.When trypsin is used to digest the wild-type Hsp16.3, its α-crystallin domain could resist such degradation.Taken together, these results indicate that the stable secondary and tertiary structures of Hsp16.3 are mainly kept by its α-crystallin domain.     

带相反电荷无机纳米片胶体稳定存在的溶剂

为了探讨采用不同溶剂所获得的带正、负电荷无机纳米片均能以稳定胶体状态存在的溶剂,用熔融盐法和均匀沉淀法分别合成带负电及正电层板的层状化合物birnessite型锰酸钠和CoAl层状双金属氢氧化物LDH,并对它们进行离子交换、剥离而制得在四甲基胺离子水溶液和甲酰胺中稳定存在的MnO2和CoAl-LDH纳米片.研究发现,甲酰胺可作为此2种纳米片胶体稳定存在的溶剂.     

网络处理器平台下基于角色的分片审计研究

提出了一种基于角色的分片审计模型，以解决因利用各个操作系统分片重组策略不同的特点进行网络渗透而导致安全审计系统识别能力降低的问题．其主要思想是：在处理畸形的分片数据包的同时，将采集终端主机的操作系统类型写入角色信息库，并根据角色信息进行分片重组转发，从而消除了分片语义歧义性．同时，提出了BSD-Linux、BSD-Right和First先行转发策略，以提高系统的性能．采用分阶段流水处理的微引擎设计模型，可使系统原型在网络处理器上得以实现．从实验结果中看出，该模型能有效提高安全审计系统的识别精度，消除分片语义歧义性．在处理大负载的情况下，先行转发策略的运用可使系统的识别精度维持在90％左右。     

基于FPGA的ATM采集卡的设计与实现

4口155 M异步传送模式（asynchronous transfer mode,ATM）业务采集卡实现对4个155 M ATM overSDH/SONET接口的数据采集,基于大容量FPGA（field programmable gate array）实现AAL2/AAL5的线速信元重组,重组后生成的AAL2SSSAR-SDU/AAL5 CPCS-SDU加上时间戳、ATM通道标识后,封装成以太网报文,通过采集输出口输出给信令协议分析服务器,可实现对Iu-CS、Iu-PS接口的信令监测,同时支持cell mode的采集应用.