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Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization

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Journal of zhejiang university-Science C(Computers and Electronics) 2011年第7期12卷 542-549页

作者： Ji-ming LI 1,2,Yun-tao QIAN 1 (1 School of Computer Science and technology,zhejiang university,Hangzhou 310027,china) (2 zhejiang Police College,Hangzhou 310053,china) School of Computer Science and technology Zhejiang University zhejiang Police College

Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral *** selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image *** this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection *** imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the *** results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.

关键词： Hyperspectral Band selection Clustering Sparse nonnegative matrix factorization

Treatment of turtle-breeding wastewater and domestic fecal sewage with soil cultivating system

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Journal of Environmental Sciences 2001年第3期13卷 342-345页

作者： LAO Shan\|gen(department of Environmental Engineering, zhejiang university,Hangzhou 310029, china) department of Environmental Engineering Zhejiang University Hangzhou 310029 China.

Turtle-breeding wastewater and domestic fecal sewage were treated by means of soil cultivating system. Results indicated that more than 50% CODCr and BOD5, of wastewaters were removed, removal rates of NH4+ -N could reach about 70%-80%, but PO43- could not be removed. The thesis analyzed functional mechanisms for pollutants and put forward main elements affecting treatment efficiencies, thus provided conditions for further research.

关键词： turtle-breeding wastewater fecal sewage soil CODCr BOD5 N P

TENSOR PRODUCTS OF JACOBSON RADICALS IN NEST ALGEBRAS

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Chinese Annals of mathematics,Series B 2003年第3期24卷 323-330页

作者： DONG ZHE Departinent of mathematics, zhejiang university, Hangzhou 310027, china. Institute of mathematics, Fudan university, Shanghai 200433, china. zhejiang Univ Dept Math Hangzhou 310027 Peoples R China Fudan Univ Inst Math Shanghai 200433 Peoples R China

This paper studies the tensor product RN RM of Jacobson radicals in nest algebras, and obtains that RN RM = {T∈B(H1 H2) : T(N M)(?)N_ M_, N∈N,M∈M}; and based on the characterization of rank-one operators in RN RM,i... 详细信息

关键词： Jacobson radical Tensor product Nest algebra

Interaction mechanisms of organic contaminants with burned straw ash charcoal

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Journal of Environmental Sciences 2010年第10期22卷 1586-1594页

作者： Wenhai Huang,Baoliang Chen department of Environmental Science,zhejiang university,Hangzhou 310028,china [a] department of Environmental Science Zhejiang University Hangzhou 310028 China

Black carbons （e.g., charcoal） have a great impact on the transport of organic contaminants in soil and water because of its strong affinity and ubiquity in the environment. To further elucidate their interaction mechanism, sorption of polar （p-nitrotoluene, m-dinitrobenzene and nitrobenzene） and nonpolar （naphthalene） aromatic contaminants to burned straw ash charcoal under different de-ashed treatments were investigated. The sorption isotherms fitted well with Freundlich equation, and the Freundlich N values were all around 0.31-0.38, being independent of the sorbate properties and sorbent types. After sequential removal of ashes by acid treatments （HCl and HCl-HF）, both adsorption and partition were enhanced due to the enrichment of charcoal component. The separated contribution of adsorption and partition to total sorption were quantified. The effective carbon content in ash charcoal functioned as adsorption sites, partition phases, and hybrid regions with adsorption and partition were conceptualized and calculated. The hybrid regions increased obviously after de-ashed treatment. The linear relationships of Freundlich N values with the charring-temperature of charcoal or biochar （the charred byproduct in biomass pyrolysis） were observed based on the current study and the cited publications which included 15 different temperatures （100-850℃）, 10 kinds of precursors of charcoal/biochar, and 10 organic sorbates.

关键词： ash charcoal organic pollutant adsorption partition effective carbon

Mechanisms of granular activated carbon anaerobic fluidized-bed process for treating phenols wastewater

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Journal of Environmental Sciences 2002年第1期14卷 132-135页

作者： LAO Shan gen (department of Environmental Engineering, zhejiang university, Hangzhou 310029, china) department of Environmental Engineering Zhejiang University Hangzhou 310029

Granular activated carbon (GAC) anaerobic fluidized bed reactor was applied to treating phenols wastewater. When influent phenol concentration was 1000 mg/L, volume loadings of phenol and COD Cr were 0 39 kg/(m 3·d) and 0 98 kg/(m 3·d), their removal rates were 99 9% and 96 4% respectively. From analyzing above results, the main mechanisms of the process are that through fluidizing GAC, its adsorption is combined with biodegradation, both activities are brought into full play, and phenol in wastewater is effectively decomposed. Meanwhile problems concerning gas liquid separation and medium plugging are well solved.

关键词： granular activated carbon (GAC) anaerobic fluidized bed phenol removal rate

Nitric oxide:A potential key point of the signaling network leading to plant secondary metabolite biosynthesis

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Progress in Natural Science:Materials International 2007年第12期17卷 1397-1404页

作者： Xu Maojun(department of Biotechnology, zhejiang Gongshang university, Hangzhou 310035, china) department of Biotechnology Zhejiang Gongshang University Hangzhou 310035 China

The endogenous signaling network of plants plays important roles in mediating the exogenous factor-induced biosynthesis of secondary metabolites. Nitric oxide (NO) has emerged as a key signaling molecule in plants recently. Numerous studies demonstrated that the main signaling molecules such as salicylic acid (SA), jasmonic acid (JA), reactive oxygen species (ROS), and NO were not only involved in regulating plant secondary metabolite biosynthesis but also interacted to form a complex signaling network by mutual inhibition and/or synergy. The recent progress in the signal network of plant secondary metabolite biosynthesis has been discussed in this paper. Furthermore, we propose a hypothetical model to show that NO might act as a potential molecular switch in the signaling network leading to plant secondary metabolite biosynthesis.

关键词： plant secondary metabolites biosynthesis signaling network nitric oxide salicylic acid jasmonic acid reactive oxygen species.

A new method for designing a developable surface utilizing the surface pencil through a given curve

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Progress in Natural Science:Materials International 2008年第1期18卷 105-110页

作者： Hongyan Zhao,Guojin Wang* department of mathematics and State Key Laboratory of CAD&CG,zhejiang university,Hangzhou 310027,china department of mathematics and State Key Laboratory of CAD&CG Zhejiang University Hangzhou 310027 China

This paper proposes a new method for designing a developable surface by constructing a surface pencil passing through a given curve, which is quite in accord with the practice in industry design and *** utilizing the Frenet trihedron frame,we derive the necessary and suffcient conditions to construct a developable surface through a given *** the requirements in shoemak- ing and garment-manufacture industries,we also study the special case of specifying the given curve as a *** given geodesic can be classified into three types corresponding to each type of developable *** also present the polynomial representation of the developable *** algorithm is convenient and effcient for applications in engineering.

关键词： CAD/CAM Developable surface Geodesic Frenet frame

Weighted weak type estimates for commutators of the Marcinkiewicz integrals

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Science china mathematics 2004年第1期47卷 83-95页

作者： DING Yong, LU Shanzhen & ZHANG Pudepartment of mathematics, Beijing Normal university, Beijing 100875, china department of Information and Computing Science, zhejiang Institute of Science and technology, Hangzhou 310033, china 1. department of mathematics Beijing Normal University 100875 Beijing China 2. department of Information and Computing Science Zhejiang Institute of Science and Technology 310033 Hangzhou China

In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities... 详细信息

关键词： Marcinkiewicz integral, commutator, Ap weight, weak type estimate.

LIL and the Approximation of Rectangular Sums of B-valued Random Variables when Extreme Terms are Excluded

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Acta Mathematica Sinica,English Series 2002年第3期18卷 605-614页

作者： Li Xin ZHANG department of mathematics Xixi Campus. zhejiang university, Hangzhou 310028, P. R. china department of mathematics Xixi Campus Zhejiang University Hangzhou P. R. China

Let {X, X_; ∈N^d} be a field of i.i.d, random variables indexed by d-tuples of positive integers and taking values in a Banach space B and let X_^((r))=X_(m) if ‖X_‖ is the r-th maximum of {‖X_‖; ≤. Let S_=∑(≤)X_ and ^((r))S_=S_-(X_^((1))+…+X_^((r)). We approximate the trimmed sums ^((r))_n, by a Brownian sheet and obtain sufficient and necessary conditions for ^((r))S_ to satisfy the compact and functional laws of the iterated logarithm. These results improve the previous works by Morrow (1981), Li and Wu (1989) and Ledoux and Talagrand (1990).

关键词： Strong approximation Trimmed sums The law of iterated logarithm