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1.
Study of the SISO mixedH
2/l1 problem for discrete time systems showed that there exists a unique optimal solution which can be approximated within any
prescribed missing error bound inl
2 norm with solvable suboptimal solutions and solvable superoptimal solutions.
Project supported by the National Natural Science Foundation of China (No. 60174026) and the Scientific Research Foundation
for Returned Overseas Chinese Scholars of Zhejiang Province (No. J20020546) 相似文献
2.
In this paper we study the scaling behavior of nucleotide cluster in 11 chromosomes of Encephalitozoon cuniculi Genome. The statistical distribution of nucleotide clusters for 11 chromosomes is characterized by the scaling behavior of P(S) ∝ e^-αs' where S represents nucleotide cluster size. The cluster-size distribution P(S1+S2) with the total size of sequential C-G cluster and A-T cluster S1+S2 were also studied. P(S1+S2) follows exponential decay. There does not exist the case of large C-G cluster following large A-T cluster or large A-T cluster following large C-G cluster. We also discuss the relatively random walk length function L(n) and the local compositional complexity of nucleotide sequences based on a new model. These investigations may provide some insight into nucleotide cluster of DNA sequence. 相似文献
3.
He W Zhang FJ Wang SP Chen G Chen CC Yan M 《Journal of Zhejiang University. Science. B》2008,9(2):100-108
Background: Sevoflurane and propofol are effective cardioprotective anaesthetic agents, though the cardioprotection of propofol has not been shown in humans. Their roles and underlying mechanisms in anesthetic postconditioning are unclear.Mitochondrial permeability transition pore (MPTP) opening is a major cause of ischemia-reperfusion injury. Here we investigated sevoflurane- and propofol-induced postconditioning and their relationship with MPTP. Methods: Isolated perfused rat hearts were exposed to 40 min of ischemia followed by 1 h of reperfusion. During the first 15 min of reperfusion, hearts were treated with either control buffer (CTRL group) or buffer containing 20 μmol/L atractyloside (ATR group), 3% (v/v) sevoflurane (SPC group),50 μmol/L propofol (PPC group), or the combination of atractyloside with respective anesthetics (SPC ATR and PPC ATR groups). Infarct size was determined by dividing the total necrotic area of the left ventricle by the total left ventricular slice area (percent necrotic area). Results: Hearts treated with sevoflurane or propofol showed significantly better recovery of coronary flow,end-diastolic pressures, left ventricular developed pressure and derivatives compared with controls. Sevoflurane resulted in more protective alteration of hemodynamics at most time point of reperfusion than propofol. These improvements were paralleled with the reduction of lactate dehydrogenase release and the decrease of infarct size (SPC vs CTRL: (17.48±2.70)% vs (48.47±6.03)%,P<0.05; PPC vs CTRL: (35.60±2.10)% vs (48.47±6.03)%, P<0.05). SPC group had less infarct size than PPC group (SPC vs PPC:(17.48±2.70)% vs (35.60±2.10)%, P<0.05). Atractyloside coadministration attenuated or completely blocked the cardioprotective effect of postconditioning of sevoflurane and propofol. Conclusion: Postconditioning of sevoflurane and propofol has cardioprotective effect against ischemia-reperfusion injury of heart, which is associated with inhibition of MPTP opening. Compared to propofol, sevoflurane provides superior protection of functional recovery and infarct size. 相似文献
4.
ZHANG Xiu-yan RUAN Hui MU Lin HE Guo-qing TANG Xing-jun CHEN Qi-he 《浙江大学学报(A卷英文版)》2006,7(11):1948-1955
INTRODUCTION Enzymes are efficient and specific biocatalysts widely used in food industries, but their application in industrial process often involves special properties not found in natural source enzymes. In order to ob- tain desirable enzymes, in the past ten years, scientists have developed rational (Kurth et al., 1998; Mouratou et al., 1999; DeSantis et al., 1999) and irrational de- sign methods (Babbitt and Gerlt, 1997; O’Brien and Herschlag, 1999) to improve the enzyme propert… 相似文献
5.
This paper proposes novel multi-layer neural networks based on Independent Component Analysis for feature extraction of fault
modes. By the use of ICA, invariable features embedded in multi-channel vibration measurements under different operating conditions
(rotating speed and/or load) can be captured together. Thus, stable MLP classifiers insensitive to the variation of operation
conditions are constructed. The successful results achieved by selected experiments indicate great potential of ICA in health
condition monitoring of rotating machines.
Project supported by the National Natural Science Foundation (No. 50205025) and the Natural Science Foundation of Zhejiang
Province (No. 5001004). 相似文献
6.
On generalized extending modules 总被引:1,自引:0,他引:1
ZENG Qing-yi 《浙江大学学报(A卷英文版)》2007,8(6):939-945
A module M is called generalized extending if for any submodule N of M, there is a direct summand K of M such that N≤K and K/N is singular. Any extending module and any singular module are generalized extending. Any homomorphic image of a generalized extending module is generalized extending. Any direct sum of a singular (uniform) module and a semi-simple module is generalized extending. A ring R is a right Co-H-ring if and only if all right R modules are generalized extending modules. 相似文献
7.
Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the
preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator
(GPT) was isolated from a cDNA library of immature seeds of rice and named asOsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of
70 amino acid residues. TheOsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression ofOsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported viaGPT can be used for starch biosynthesis in rice nongreen plastids.
Project supported by National Natural Scienc Foundation of China (No.39830250) and Natural Science Foundation of Zhejiang
Province (No.2A0106), China. The nucleotide sequence data will appear in the GenBank under accession number AF375053. 相似文献
8.
The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm,Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer
vector pVL 1392 used as a tool to target the L-chain region of the silkworm genome. Genomic DNA from their offsprings was
extracted and the expected targeting was detected using polymerase chain reaction and DNA sequencing, as well as protein analysis.
The results showed that positive events occurred and that the FGF gene was integrated into the L-chain locus through homologous
recombination.
Project supported by the Scientific Research Foundation for Returned Overseas Chinese Scholars, Education Ministry of China
and the Natural Science Foundation of Zhejiang Province (No. 301306), China 相似文献
9.
INTRODUCTION In recent years theory of extending modules and rings has come to play an important role in the theory of rings and modules. A module is called an extending module (or CS-module) if every submodule is essen- tial in a direct summand, or equivalently, every closed submodule is a direct summand. Although this gen- eralization of injectivity is extremely useful, it does not satisfy some important properties. For example, direct sums of extending modules need not be ex- tending;… 相似文献
10.
INTRODUCTION Monocrystalline SBN (Strontium barium nio-bium, SrxBa1?xNb2O6, denoted SBNx?100, where 0.25≤x≤0.75) solid solution, is currently being inves-tigated as potential material for many micro-device applications, such as piezoelectric infrared detectors, piezoelectric, electro-optic modulators, and holo-graphic storage (Koch et al., 1998), because SBN has one of the largest known linear electro-optic coeffi-cients (r33=1300 pm/V for SBN75), two orders of magnitude larger th… 相似文献
11.
YANG Cheng-lei QI Meng MENG Xiang-xu LI Xue-qing WANG Jia-ye 《浙江大学学报(A卷英文版)》2006,7(9):1522-1529
INTRODUCTION To compute the minimum distance between two convex polygons or polyhedrons is often a main step of many applications, such as collision detection (Choi et al., 2006; Li et al., 2003), path planning. In order to reduce the time complexity of the algorithm as much as possible, the convex property must be applied fully. Edelsbrunner (1985) proposed an algorithm for computing the minimum distance between two dis- joint convex polygons. The algorithm takes O(logm logn) time, and … 相似文献
12.
HUANG Wen-liang LI Shi-jian LIU Duo 《浙江大学学报(A卷英文版)》2007,8(12):1971-1982
Localization is one of the substantial issues in wireless sensor networks. The key problem for the mobile beacon localization is how to choose the appropriate beacon trajectory. However, little research has been done on it. In this paper, firstly, we deduce the number of positions for a beacon to send a packet according to the acreage of ROI (region of interest); and next we present a novel method based on virtual force to arrange the positions in arbitrary ROI; then we apply TSP (travelling salesman problem) algorithm to the positions sequence to obtain the optimal touring path, i.e. the reduced beacon trajectory. When a mobile beacon moves along the touring path, sending RF signals at every position, the sensors in ROI can work out their position with trilateration. Experimental results demonstrate that the localization method, based on the beacon reduced path, is efficient and has flexible accuracy. 相似文献
13.
Zhang Xin Zhang Bing-xin Zhang Zhen Shen Wei-feng Yang Ching-hong Yu Jing-quan Zhao Yu-hua 《Journal of Zhejiang University. Science. B》2005,6(8):770-777
Fusarium head blight (FHB) caused byFusarium graminearum is a devastating disease that results in extensive yield losses to wheat and barley. A green fluorescent protein (GFP) expressing
plasmid pRP22-GFP was constructed for monitoring the colonization of two biocontrol agents,Brevibacillus brevis ZJY-116, on the spikes of barley and their effect on suppression of FHB. Survival and colonization of theBrevibacillus brevis ZJY-1 andBacillus subtilis ZJY-116 strains on spikes of barley were observed by tracking the bacterial transformants with GFP expression. Our field
study revealed that plasmid pRP22-GFP was stably maintained in the bacterial strains without selective pressure. The retrieved
GFP-tagged strains showed that the bacterial population fluctuation accorded with that of the rain events. Furthermore, both
biocontrol strains gave significant protection against FHB on spikes of barley in fields. The greater suppression of barley
FHB disease was resulted from the treatment of barley spikes with biocontrol agents before inoculation withF. graminearum.
Project supported by the National Natural Science Foundation of China (No. 30230250) and Science and Technology Committee
of Zhejiang Province (No. 2003C22029), China 相似文献
14.
The effects of pH andEh on release of nitrogen and phosphorus from sediments of West Lake under different conditions were investigated by simulation
test. Results showed that the net flux of NH4
+-N release from sediments increased with pH, but NO3
−-N showed negative-going release at all tested pH levels. The net flux of NH4
+-N release from sediments was higher under anaerobic or aerobic condition of the overlying water, but only under aerobic condition
would net release of NO3
−-N occur. It was also shown that phosphorus released was mainly in its inorganic form, higher pH and anaerobic conditions
of overlying water greatly stimulated release of phosphorus. In situ measurement at several West Lake locations indicated
that sediment resuspension induced by boat propeller stimulated nutrients release from sediment into overlying water.
Project (No.294059) supported by National Natural Science Foundation of Zhejiang Province, China 相似文献
15.
The dual formulation of the discrete-time mixedl
2/l
1 control design problem was achieved by using the duality theory of Lagrange multipliers. For some special dual mixedl
2/l
1 problems, an approximation method for the optimal value is introduced. A suboptimal value of the infinite-dimensional dual
problem can be obtained by solving a sequence of truncated problems. The convergence property of the solution scheme is investigated.
This paper gives a low approximation method for the primal problem.
Project(699085) supported by Zhejiang Provincial Natural Science Foundation of China. 相似文献
16.
Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed
by intramolecular cyclization of 1,1-dicyanoalkenes under mild conditions.
Preject (No. 20072033) supported by the National Natural Science Foundation of China, and Zhejiang Provincial Natural Science
Foundation of China 相似文献
17.
In 1935 ,P .Erd¨osandGSzekeresobtainedtheclassicalinequalityR (m ,n)≤R (m - 1,n) R(m ,n - 1) . In 196 8,K .WalkerprovedthatR(n ,n)≤ 4R(n- 2 ,n) 2 . In 1998,HuangY .R .andZhangK .M .[1,2 ] provedthatR(m ,n)≤ 12 (β 3γ 5 ) 12 γ(4α 2 β - 3γ 6 ) (β 1) 2 Inthispaper ,weobtainsomenewupperboundsforR(m ,n ,l)andR(m … 相似文献
18.
A new optimization algorithm based on chaos 总被引:8,自引:0,他引:8
LU Hui-juan ZHANG Huo-ming MA Long-hua 《浙江大学学报(A卷英文版)》2006,7(4):539-542
INTRODUCTION Chaos (Wang et al., 2002) is a common nonlin- ear phenomenon, whose action is complex and similar to that of randomness. The characteristics of chaos being highly sensitive to the initial value of chaos make a world of differences due to the ergodic prop- erty of the phase space—chaos can go through all states in certain ranges without repetition; the inher- ent randomness of the system—means that chaos behavior is similar to randomness which is disorderly; but at the same t… 相似文献
19.
JIA Ling LI Fang 《浙江大学学报(A卷英文版)》2006,7(12):2088-2092
INTRODUCTION In (Auslander, 1995), the author established the relationship of homological dimension between skew group algebra ΛG and Λ. Recall from Corollary 4.7 and Corollary 4.10 in (Auslander, 1995) that gl.dim(ΛG)=gl.dim(Λ) where ΛG is a skew group algebra with the order of G invertible in Λ. Recently, more and more mathematicians have studied homological dimension for Hopf algebra. Yang (2002) gave the relationship of homological dimension between smash product algebra A#H… 相似文献
20.
This paper presents a sliding mode (SM) based identifier to deal with the parameter identification problem for a class of
parameter uncertain nonlinear dynamic systems with input nonlinearity. A sliding mode controller (SMC) is used to ensure the
global reaching condition of the sliding mode for the nonlinear system; an identifier is designed to identify the uncertain
parameter of the nonlinear system. A numerical example is studied to show the feasibility of the SM controller and the asymptotical
convergence of the identifier.
Project supported by the National Natural Science Foundation of China(No. 69974035) and Zhejiang Provincial Natural Science
Key Foundation of China (ZD9905) 相似文献