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111.
One quarter scale experiment device of a typical L - shape architecture structure including a burning room and an adjacent hallway is established to carry out the research. The smoke characteristics at the sampling points below the ceiling of the burning compartment and the roof of the hallway are studied systematically to find out the effects of different ceilings on the local fire origin compartment and the smoke transportation to a remote area. A series of tests is reported and the smoke residence time, the concentration peak and the concentration build up rate are investigated as functions of the type of the ceiling. The smoke residence time, the most important factor concerning smoke toxicity, is described by a novel concept, wavelength, in this study. Furthermore, it is worth emphasizing that the PVC ceiling exhibits a phenomenon of frequent collapse during the fire developing period. The single heat action is conducted to judge the smoke and the heat effect on the fire risk. 相似文献
112.
Adaptive unscented Kalman filter for parameter and state estimation of nonlinear high-speed objects
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An adaptive unscented Kalman filter (AUKF) and an augmented state method are employed to estimate the timevarying parameters and states of a kind of nonlinear high-speed objects. A strong tracking filter is employed to improve the tracking ability and robustness of unscented Kalman filter (UKF) when the process noise is inaccuracy, and wavelet transform is used to improve the estimate accuracy by the variance of measurement noise. An augmented square-root framework is utilized to improve the numerical stability and accuracy of UKF. Monte Carlo simulations and applications in the rapid trajectory estimation of hypersonic artillery shells confirm the effectiveness of the proposed method. 相似文献
113.
To discuss the applicability of advanced composite carbon fiber reinforced polymer (CFRP) and ultra-high performance concrete reactive powder concrete (RPC) in super-long span cable-stayed bridges , ta... 相似文献
114.
I-doped Bi_2Te_(3-x)I_x(x=0, 0.05, 0.1, 0.2) flower-like nanoparticles were synthesized by a hydrothermal method through a careful adjustment of the amount of ethylenediamine tetraacetic acid surfactant. The nanopowders of flower-like nanoparticles were hot-pressed into bulk pellets and the thermoelectric properties of the pellets were investigated. The results showed that I-doping decreased the electrical resistivity effectively, and the thermal conductivitives of the Bi_2Te_(3-x)I_x bulk samples was lower because of the closer atomic mass of I compared to Te.As a result, a ZT value of 1.1 was attained at 448 K for the Bi_2Te_(2.9)I_(0.1)sample. 相似文献
115.
116.
Xin Yang Fang Liu 《系统科学与信息学报》2006,4(1):53-57
This paper introduces the disposition effect into asset pricing process, and sets dynamic equilibrium model on which we can discuss the pattern of risk assets' returns. On base of theory results, we use data of China stock market to analyze the influence of disposition effect on stock return. The empirical study result confirms the disposition effect's existence in China stock market and it does affect the stock return. 相似文献
117.
LI Haiyan TANG Beish XIA Kun CAO Guifang SHEN Lu JIANG Hong PANQian SONG Yanmin CAI Fang 《自然科学进展(英文版)》2005,15(8):757-760
Benign familial neonatal convulsions (BFNC) is a rare autosomal dominant inherited epilepsy syndrome. Two voltage-gated potassium channel genes, KCNQ2 and KCNQ3, have been identified as the genes responsible for BFNC. Here we report two Chinese families with clinical histories of typical BFNC. Using six microsatellite markers, two located at KCNQ2 locus and four at KCNQ3 locus, linkage analysis was performed in the two families, which excluded the linkage of BFNC to KCNQ3, but could not exclude the linkage to KCNQ2. Direct DNA sequencing of the KCNQ2 gene in the two families was performed, and two formerly unknown polymorphisms were identified, but no KCNQ2 mutation was found in the two families. Our study suggests the genetic heterogeneity in Chinese families with BFNC and proves the existence of a new gene locus for BFNC. 相似文献
118.
This paper introduces the definitions and causes of LD,pointing out that English LD is definitely concerned with the factor of affect by exploring the three theories like Affective Filter Hypothesis,Humanistic Approach to Education and Attribution Theory. 相似文献
119.
GF14 widely occurs in plant species functioning as a regulatory protein in cell signal transdution,including monoamine synthesis,exocytosis and cell cycle regulation.A partial sequence,413bp in length,is cloned from the bulbs of F.crrihosa by means of RT-CPR technique.Sequence alignment with the BLAST program shows that it is highly similar to GF14 gene.A new full-length cDNA,1133bp,is obtained by RACE techniques,It contains a major open reading frame of 262 amino acids,5‘ and 3‘untranslated regions and a long Poly(A) tail,Sequence analysis of deduced GF14 protein from F.crrihosa indicates several conserved motifs of GF14 protiens are also found in sequence of GF14 protein of F.crrihosa. 相似文献
120.