IEEE 802.16协议物理层的System View仿真

采用软件仿真工具System View对IEEE 802.16协议物理层的下行链路进行了仿真,给出了仿真结果,并对采用不同调制方式和编码方式时的误比特率性能分别进行了分析和比较.     

Homocysteine increases the synthesis of adrenomedullin in vascular fibroblasts of rats

Homocysteine (Hcy), a highly reactive sulfur- containing amino acid, is an intermediate product of methionine metabolism. Elevation of plasma Hcy has been widely studied as an independent risk factor for many cardiovascular diseases such as atherosclerosis, thrombosis, etc.[1]. Inherited hyperhomocysteinemia cases usually suffer from occlusion or thrombosis in arteries and large veins before the age of 20. Hyperhomocysteinemia significantly reduces the survival rate[2] and dilatation functi…     

Myosin V orientates the mitotic spindle in yeast

Coordination of spindle orientation with the axis of cell division is an essential process in all eukaryotes. In addition to ensuring accurate chromosomal segregation, proper spindle orientation also establishes differential cell fates and proper morphogenesis. In both animal and yeast cells, this process is dependent on cytoplasmic microtubules interacting with the cortical actin-based cytoskeleton, although the motive force was unknown. Here we show that yeast Myo2, a myosin V that translocates along polarized actin cables into the bud, orientates the spindle early in the cell cycle by binding and polarizing the microtubule-associated protein Kar9 (refs 7-9). The tail domain of Myo2 that binds Kar9 also interacts with secretory vesicles and vacuolar elements, making it a pivotal component of yeast cell polarization.     

Geodetic evidence for a low slip rate in the Altyn Tagh fault system

The collision between India and Asia has been simulated with a variety of computational models that describe or predict the motions of the main faults of east Asia. Geological slip-rate estimates of 20-30 mm yr(-1) suggest that the largest of these faults, the 2,000-km-long Altyn Tagh fault system on the northern edge of the Tibetan plateau, absorbs as much of the Indo-Asian convergence signal as do the Himalayas--partly by oblique slip and partly by contraction and mountain growth. However, the predictions of dynamic models for Asian deformation and the lower bounds of some geological slip-rates estimates (3-9 mm yr(-1); refs 7, 8) suggest that the Altyn Tagh system is less active. Here, we report geodetic data from 89-91 degrees E that indicate left-lateral shear of 9 +/- 5 mm yr(-1) and contraction of 3 +/- 1 mm yr(-1) across the Altyn Tagh system. This result--combined with our finding that, at 90 degrees E, Tibet contracts north-south at 9 +/- 1 mm yr(-1)--supports the predictions of dynamic models of Asian deformation.     

倒立摆控制方法的研究

运用牛顿动力学方法对单级倒立摆系统进行了数学建模,并对基于经典控制理论的PID控制法、基于自适应神经网络模糊控制方法进行了仿真对比分析研究。     

超生产容量阻止对手进入有效性的实物期权分析

将产业中企业竞争的策略行为推广到不确定性的市场环境中,用实物期权分析方法研究了行业内的垄断企业阻止具有决策灵活性的潜在进入者时,投资超生产容量策略的有效性.研究基于行业内企业的生产容量对进入者项目价值的影响评估,给出了业内企业生产容量对对手的进入期权价值和投资决策的影响结果,证明了当潜在进入者有足够的决策灵活性:投资前持有进入期权,投资后持有暂时停止和恢复期权时,对业内企业设置的任何生产容量,潜在进入者都会等待有限的时间后投资进入行业,即在净现值分析方法下有效的、以超生产容量阻止进入的竞争策略,对于持有投资和生产决策期权的进入者是无效的.     

INFORMATION CHARACTERIZATION OF COMMUNICATION CHANNELS FOR SYSTEM IDENTIFICATION

This paper studies identification of systems in which the system output is quantized, transmitted through a digital communication channel, and observed afterwards. The concept of the CR Ratio is introduced to characterize impact of communication channels on identification. The relationship between the CR Ratio and Shannon channel capacity is discussed. Identification algorithms are further developed when the channel error probability is unknown.     

孔隙结构表征陶粒滤料净水效能的方法

在分析陶粒的吸附性能和孔隙结构的基础上,采用浊度和UV254等动态实验方法研究了陶粒滤料的净水效能,建立了陶粒滤料过滤性能的表征方法.结果表明,陶粒的比表面积和碘吸附值、孔体积和单宁酸吸附值、最可几孔径与全部吸附值的相关系数分别是0.99、0.92和1.00.其表征方法所得的陶粒滤料评价结果与陶粒滤料净水效能的实验结果相符,为评价陶粒滤料的净水效能和针对不同水质选择陶粒滤料提供了标准.     

Enolate chelating N-heterocyclic carbene complexes of Fe(II): Synthesis, structure and their catalytic activity for ring-opening polymerization of ε-caprolactone

The reaction of anhydrous FeBr2 with two equivalents of anionic N-heterocyclic carbene (NaL1 and NaL2), which are generated in situ by the reaction of the corresponding salt [4-R-C6H4COCH2{CH- (NCHCHNiPr)}Br] (R = OCH3, H2L1Br, 1; R = F, H2L2Br, 2) with two equivalents of NaN(SiMe3)2, affords bis-ligand Fe(II) complexes of L12Fe (3) and L22Fe (4) in high yield, respectively. Attempt to synthesize mono-ligand Fe(II) bromide by the 1:1 molar ratio of NaL to FeBr2 is unsuccessful, and the same com- plexes of 3 and 4 were obtained. Both 3 and 4 have been depicted by elemental analysis and X-ray structure determination. Preliminary studies show that both 3 and 4 can be used as single-component catalyst for the ring-opening polymerization of ε-caprolactone, and the catalytic activity of 3 is higher than that of 4.     

提高超声波测距精度的方法

基于宏晶公司新近推出的STC12C5410单片机,通过利用温度校正、标杆校正、软件校正的方法实现超声波测距精度由厘米级向毫米级跨进的方法。给出了硬件设计电路图及软件的流程图。在电路的实际测试过程中,成功地达到了预期的效果。