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61.
本文提出了一种由神经元网络与线性自适应滤波器组成的集成滤波器的实现方法,用于谱图信号除噪处理。 相似文献
62.
Jun-Ichi Kikuchi Yukito Murakami 《Journal of inclusion phenomena and macrocyclic chemistry》1998,32(2-3):209-221
Steroid cyclophanes, bearing four bile acid moieties covalently placed on a tetraazaparacyclophane skeleton, were designed and synthesized as artificial cell-surface receptors. Guest-binding behavior of the steroid cyclophanes embedded in a bilayer membrane formed with a synthetic peptide lipid was clarified by means of fluorescence and circular dichroism spectroscopy. We found that the steroid cyclophane effectively bound aromatic guests in both bilayer membranes and aqueous solution. In addition, copper(II) ions acted as a guest species for the steroid cyclophane and a competitive inhibitor toward a NADH-dependent lactate dehydrogenase (LDH). On these grounds, we constituted a supramolecular assembly as an artificial signaling system in combination with the steroid cyclophane, a cationic peptide lipid, and LDH. As a consequence, the steroid cyclophane acted as an effective artificial cell-surface receptor being capable of transmitting an external signal to the enzyme in collaboration with copper(II) ions as a signal transmitter. 相似文献
63.
Jeong Hwan Kim Ji Hoon Ko Byeong-Soo Bae 《Journal of Sol-Gel Science and Technology》2007,41(3):249-255
Multi-scale hybrid nanocomposites containing both ∼15 nm silica colloids and ∼2 nm oligosiloxanes in a methacryl polymer matrix
were newly designed and fabricated. Colloidal silica sols were dispersed in methacryl oligosiloxanes nano-hybrid resins synthesized
by sol-gel reaction of methacryloxypropylmethoxysilane and diphenylsilanediol. On the basis of TEM and SANS analyses, it was
confirmed that the silica colloids were compatibly dispersed and different sizes of colloidal silica and oligosiloxanes co-exist
in the solutions. Multi-scale hybrid nanocomposites fabricated by UV and thermal curing with incorporation of silica colloids
in the nano-hybrid materials show enhanced mechanical and thermal characteristics. 相似文献
64.
苯及其衍生物甲苯,一氯代苯都是重要的有机试剂和化工原料,也是对人体有害的有机物。为了了解这些有机试剂对处于生物液晶态的生物膜毒害的机理,我们以含水卵磷脂组成的液晶体系作为人工模型用小角X射线散射(SAXS)方法探讨这些有机试剂对它们结构的影响。关于苯或其它非极性有机介质与含水卵磷脂形成液晶体系及其结构模型前人有一些报导。 相似文献
65.
研究了高效液相色谱-火焰原子吸收光谱联用系统分析信号处理方法,比较了各种处理方法的优缺点,用积分与适应平滑法综合处理色谱峰分析信号,不仅能有效地消除噪声,而且能使分析信号得到加强,以测定镍为例,经积分与适应平滑法综合处理后,检出限改善了2.7倍。 相似文献
66.
针对道路维修施工期间常采用的部分路面封闭施工且利用辅路进行分流的情形,探讨了交通分流信控优化模型。借助交通流波动理论,分析了施工路段及其前后车流拥挤排队及疏散特征和规律,分析了对车流进行控制需满足的约束,并分析了车流的延误计算公式。以总的车辆行驶时间最小化目标,原路径及分流路径的绿时分配及信号周期为优化参数,考虑交通分流控制的各种约束,建立了道路施工路段交通分流信控优化模型。分析了该模型属于非凸问题,因此提出了一种近似求解最优解的办法。通过一个示例对模型和求解算法进行了验证,并对一些规律性结果进行了分析。 相似文献
67.
Least squares estimations have been used extensively in many applications, e.g. system identification and signal prediction. When the stochastic process is stationary, the least squares estimators can be found by solving a Toeplitz or near-Toeplitz matrix system depending on the knowledge of the data statistics. In this paper, we employ the preconditioned conjugate gradient method with circulant preconditioners to solve such systems. Our proposed circulant preconditioners are derived from the spectral property of the given stationary process. In the case where the spectral density functions() of the process is known, we prove that ifs() is a positive continuous function, then the spectrum of the preconditioned system will be clustered around 1 and the method converges superlinearly. However, if the statistics of the process is unknown, then we prove that with probability 1, the spectrum of the preconditioned system is still clustered around 1 provided that large data samples are taken. For finite impulse response (FIR) system identification problems, our numerical results show that annth order least squares estimator can usually be obtained inO(n logn) operations whenO(n) data samples are used. Finally, we remark that our algorithm can be modified to suit the applications of recursive least squares computations with the proper use of sliding window method arising in signal processing applications.Research supported in part by HKRGC grant no. 221600070, ONR contract no. N00014-90-J-1695 and DOE grant no. DE-FG03-87ER25037. 相似文献
68.
Z. Shi 《Journal of Theoretical Probability》1996,9(4):915-929
LetR be the radial part of ad-dimensional Wiener process, starting from 0. In this paper, small ball probabilities are evaluated for sup0<11(t
–p
R(t)) and sup
t
0(e
–1
R(t)), withp[0, 1/2]. Chung's law of the iterated logarithm is established for the supremum of the local times of a two-dimensional Bessel process. 相似文献
69.
1 INTRODUCTION The bimetallic nanoclusters are of standing inte- rest since they can exhibit catalytic, electronic and optical properties distinct from those of corre- sponding pure nanoclusters[1~4]. Palladium and pla- tinum, well known for their catalytic properties, are often used as the catalyst in different fuel cells[5~8]. Several experimental results illustrate that for the oxygen reduction reaction (ORR), which is one of the primary reactions taking place in many fuel cells and… 相似文献
70.
W. Wilke 《Colloid and polymer science》1981,259(6):577-586
Summary A brief review of one and three dimensional models of paracrystalline superstructures in polymers, as used for analysing the small angle scattering, is given.
Zusammenfassung Es wird ein knapper überblick über die bei der Analyse der Kleinwinkelstreuung von Polymeren verwendeten einund dreidimensionalen Modelle der Überstruktur gegeben.相似文献