基于整数线性规划的MPSoC通信优化策略

摘要： 针对多处理器片上系统 (Multiprocessor System on chip,MPSoC) 的通信优化技术--通信流水线和消息聚合,其过度使用可能会导致系统同步开销上升从而带来整体系统性能降低的问题,提出了基于整数线性规划(Integer Linear Programming, ILP)的优化策略.该策略以综合优化系统通信和同步开销为目标,通过对通信流水线技术和消息聚合技术的合理规划,使系统性能达到最优.实验结果表明,基于ILP的通信优化策略能够充分发挥通信优化技术的优点,使系统性能显著提升.
关键词： 通信优化; 整数线性规划; Simulink
中图分类号： TP 31文献标志码： A     

医疗无线传感器网络匿名认证机制

针对无线医疗传感器网络的特点,以智能卡和口令作为身份认证与密钥交换的基础,提出了一种匿名认证机制,主要包括注册、登陆、认证以及口令更新4个阶段.该机制可以保证专业人员及其病人的匿名性,实现传感器节点与专业人员之间的双向认证以及网关、传感器节点、专业人员之间的公平的密钥协商;与此同时,利用静态Diffie-Hellman密钥、会话密钥对传输过程的相关信息进行加密,保证其机密性.     

Controlled synthesis of HBsAg in a differentiated human liver carcinoma-derived cell line.

A significant aspect of primary hepatic carcinoma in man is the high positive correlation of hepatocellular carcinoma with infection with hepatitis B virus (HBV)1. Analysis of the relationship between HBV infection and oncogenesis is difficult because natural infection with HBV is limited to man and experimental infection has been achieved only in chimpanzees and gibbons. Furthermore, because HBV has not been successfully propagated in cell culture, basic study of virus-cell interaction of the aetiological agent of one of the most widespread infections of man has been impossible. Recently, however, a cell line (PLC/PRF/5) derived from a human hepatoma biopsy was described which produces the HRV surface antigen (HBsAg) and so provides a tool for the experimental investigation of HBV in viro. We now report the derivation and characterisation of two additional cell lines primary liver carcinomas. In contrast to the PLC/PRF/5 cell line, these cell lines retain the capacity to synthesise many human plasma proteins, including both albumin and alpha-fetoprotein (AFP). One of these lines also produces BHsAg. We also present evidence that HBsAg synthesis and secretion in this cell line are correlated with the growth state of the culture. This finding is in contrast to the continuous HBsAg production found in the PLC/PRF/5 cell line.     

颗粒级配对火山灰力学特性影响的试验研究

以吉林省靖宇县的黑色、红色两种火山灰为原材料,分别配制了5种不同级配的试样.通过土粒相对密度、矿物成分与颗粒形态、直接剪切和固结试验分析,得到该火山灰材料的土粒相对密度、化学成分、颗粒形态、剪切强度、压缩性等物理力学特性,并分析了5种级配的中值粒径d50和不均匀系数cu对火山灰剪切强度的影响.靖宇火山灰主要由泡沫状的火山玻璃组成,未经历过长期水力、风力的磨圆作用,颗粒棱角分明,其剪切特性与干沙土类似,内聚力很小,剪切强度受级配的影响较大.在配制的5种级配曲线的粒径范围,试样的内摩擦角随着中值粒径d50的增大而增大,不均匀系数cu对试样内摩擦角的影响较小.     

Positive regulation of apoptosis signal-regulating kinase 1 by dual-specificity phosphatase 13A

Apoptosis signal-regulating kinase 1 (ASK1), a member of the MAP kinase kinase kinase, is activated by several death stimuli and is tightly regulated by several mechanisms such as interactions with regulatory proteins and post-translational modifications. Here, we report that dual-specificity phosphatase 13A (DUSP13A) functions as a novel regulator of ASK1. DUSP13A interacts with the N-terminal domain of ASK1 and induces ASK1-mediated apoptosis through the activation of caspase-3. DUSP13A enhances ASK1 kinase activity and thus its downstream factors. Small interfering RNA (siRNA) analyses show that knock-down of DUSP13A in human neuroblastoma SK-N-SH cells reduces ASK1 kinase activity. The phosphatase activity of DUSP13A is not required for the regulation of ASK1. This regulatory action of DSUP13 on ASK1 activity involves competition with Akt1, a negative regulator of ASK1, for binding to ASK1. Taken together, this study provides novel insights into the role of DUSP13A in the precise regulation of ASK1.     

Chaperonin-mediated stabilization and ATP-triggered release of semiconductor nanoparticles

Various properties of semiconductor nanoparticles, including photoluminescence and catalytic activity, make these materials attractive for a range of applications. As nanoparticles readily coagulate and so lose their size-dependent properties, shape-persistent three-dimensional stabilizers that enfold nanoparticles have been exploited. However, such wrapping approaches also make the nanoparticles insensitive to external stimuli, and so may limit their application. The chaperonin proteins GroEL (from Escherichia coli) and T.th ('T.th cpn', from Thermus thermophilus HB8) encapsulate denatured proteins inside a cylindrical cavity; after refolding, the encapsulated proteins are released by the action of ATP inducing a conformational change of the cavity. Here we report that GroEL and T.th cpn can also enfold CdS semiconductor nanoparticles, giving them high thermal and chemical stability in aqueous media. Analogous to the biological function of the chaperonins, the nanoparticles can be readily released from the protein cavities by the action of ATP. We expect that integration of such biological mechanisms into materials science will open a door to conceptually new bioresponsive devices.     

半平面上有限级B值Dirichlet级数的增长性

研究了有关B值Dirichlet级数的一些基本性质,扩充了B值Dirichlet级数的理论.在此基础上,研究了B值Dirichlet级数的增长级,得到了正规增长的几个充分必要条件.     

广义 Korteweg-de Vries-Burgers 方程解的一致估计

考查了广义Korteweg-de Vries-Burgers方程ut f(u)x=μuxx δuxxx的Cauchy问题解的一致估计。粗略地讲就是Korteweg-de Vries-Burgers方程是无粘Burgers方程的一个粘性逼近。     

Mismatch-specific post-meiotic segregation frequency in yeast suggests a heteroduplex recombination intermediate

Post-meiotic segregation of alleles, which is seen, for example, in the 5:3 distribution of alleles in the products of a single meiosis in fungi, has been thought to be due to the non-repair of heteroduplex regions formed during genetic recombination. In current models of genetic recombination, heteroduplex DNA is formed either as the primary intermediate generated by two interacting non-sister chromatids or as a short region flanking a double-stranded gap. The frequency of post-meiotic segregation differs for different alleles, and this is presumed to reflect the varying efficiencies with which different types of mismatches in the heteroduplex are repaired. To gain some insight into this process, we have now determined the nucleotide sequences of various yeast alleles with different post-meiotic segregation frequencies and compared the mismatches predicted to occur in heteroduplexes of these alleles with wild-type DNA with those repaired with varying efficiency in bacterial systems. A striking correlation is observed, with the mismatches predicted for high post-meiotic segregation frequency alleles being similar to mismatches repaired with low efficiency in bacteria. These results support the view that postmeiotic segregation frequency reflects heteroduplex repair efficiency and the contention that meiotic gene conversion is the result of the successful repair of heteroduplex mismatches.