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Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2.& ZHENG Gang2.1 college of information & Control, Nanjing University of information science & technology, Nanjing 2.0044, china 2.college of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 2.0016, china 1. college of information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. college of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

Fuzzy tolerance quotient spaces and fuzzy subsets

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science china({2. sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2.3,4* 1Computer science & technology {2., Anhui University, Anhui 2.0039, china 2.tate Key Laboratory of Intelligent technology and Systems, Beijing 100084, china 3Tsinghua National Laboratory of information science & technology, Beijing 100084, china 4information science & technology {2., Computer science & technology Department, Tsinghua University, Beijing 100084, china 1. Computer science & technology {2. Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2. the definition of isomorphism of fuzzy tolerance relations; (3) the isomorphic discriminant of fuzzy tolerance relations; (4) the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

Metal Transfer of Twin-wire Indirect Arc Argon Welding

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稀有金属材料与工程 2011年第S3期40卷 156-159页

作者： Cao Meiqing1, Zou Zengda2. Zhang Shunshan2. Qu Shiyao2.1Shandong University of science and technology, {2. 2.6510, china 2.handong University, Jinan 2.0061, china Shandong Univ Sci & Technol Sch Mat Sci & Engn Qingdao 266510 Peoples R China Shandong Univ Jinan 250061 Peoples R China

Metal transfer of twin-wire indirect arc argon welding was investigated with high speed camcorder system based on a xenon lamp source and digital oscillograph, forces on droplet were analyzed in this paper. Results show metal transfer mode that of anodal and cathodal is not completely the same. It was divided into seven types of transfer mode; spray transfer and spray-projected transfer are the important transfer mode. The base-plate was melted by energy that of the arc and drop carrying, the drop transfer direction is different from that of the current flow, anodal and cathodal drop transfer at the same time, only the frequence and size are different.

关键词： indirect arc metal transfer short circuiting transfer transfer mode

Physiological and ultralstructural changes of Chlorella sp. induced by UV-B radiation

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Progress in Natural science:Materials International 2005年第8期15卷 678-683页

作者： YU Juan1, TANG Xuexi1*, ZHANG Peiyu 1,2. TIAN Jiyuan1 and DONG Shuanglin1(1. Division of Life science and technology, Ocean University of{2., qingdao 2.6003,{2. 2. college of Life sciences, Qufu Normal University, Qufu 2.31653,{2.) Division of Life science and technology Ocean University of China Qingdao 266003 China. college of Life sciences Qufu Normal University Qufu 2731653 China

In order to investigate the mechanisms of enhanced UV-B radiation on algae, the effects of UV-B radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-B radiation could inhibit the growth and photosynthesis of microalgae. UV-B radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-B radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp. without exposure to UV-B showed that the thylakoid lamellae were clear and regular, the stroma of its chloroplast was apparent and clear. The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-B radiation at dose of 2.88 kJ/m2. the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2.UV-B radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-B radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-B radiation they exposed to.

关键词： UV-B radiation physiological changes ultrastructure Chlorella sp.

A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (college of Computer science and {2., Huazhong University of science and {2., Wuhan 430074, china) college of Computer science and {2. Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity information

Improved electrochemical performances of polyaniline nanotubes-poly-L-lysine composite for label-free impedance detection of DNA hybridization

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science china Chemistry 2010年第6期53卷 1371-1377页

作者： YANG Tao,JIANG Chen,ZHANG Wei & JIAO Kui Key Laboratory of Eco-chemical Engineering,Ministry of Education college of Chemistry and Molecular Engineering,qingdao University of {2. and technology,qingdao 2.6042.china 1. Key Laboratory of Eco-chemical Engineering Ministry of Education college of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 China

A sensitive label-free DNA hybridization biosensing platform was fabricated based on the synergistic effect of polyaniline nanotubes (PANInt) and poly-L-lysine (pLys).The composite of pLys and PANInt was coated onto the carbon paste electrode (CPE) to form a uniform and very stable nanocomposite *** pLys in the composite film not only acts as a membrane to retain good electron transfer capability of PANInt even at physiological pH,but also possesses fine biocompatibility for *** probes with negatively charged phosphate groups were readily linked to the positively charged pLys surface due to the strong electrostatic *** synergistic effect of PANInt and pLys could significantly enhance the sensitivity of DNA hybridization *** phosphinothricin acetyltransferase (PAT) gene fragment from transgenic corn and the polymerase chain reaction amplification of the terminator of nopaline synthase gene from the real sample of a kind of transgenic soybean were detected by this DNA electrochemical biosensor via label-free impedance *** stable composite gives convenient permselectivity properties as a transducer material for the design of modern electrochemical impedance biosensor using [Fe(CN)6]3-/4as an indicator.

关键词： poly-L-lysine polyaniline nanotubes DNA electrochemical biosensor PAT gene NOS gene

Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.Department of Chemical Physics,University of science and technology of{2.,Hefei 2.002.,china 2.college of Physics and Electronic information,Anhui Normal University,Wuhu 2.1000,china 1. Department of Chemical Physics University of Science and Technology of China 230026 Hefei China 2. college of Physics and Electronic information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Sedimentary facies of the Silurian tide-dominated paleo-estuary of the Tazhong area in the Tarim Basin

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Petroleum science 2008年第2期5卷 95-104页

作者： Zhang Jinliang Zhang Zhongjie college of Resource science and {2. Beijing Normal University Beijing 100875 China School of Marine Geo-science Ocean University of China Qingdao Shandong 266100 China

As the relative sea-level rose, a paleo-estuary was formed by the marine inundation of the braided river incised valley during the period of the lower sub-member of the upper member of the Kalpingtage. formation of the Silurian in the Tarim Basin, west china. Sandstone-mudstone rhythmite, tidal structures and bimodal cross-bedding are common in these deposits, indicating that tides played a significant role in generating the sedimentary structures and the estuary type was tide-dominated. Five depositional facies were grouped： tidal river, sandy and muddy subtidal flat, tidal flat, tidal bar, tidal channel on the basis of lithology, electric properties, rhythmicity, sedimentary structure, fossil and the contact relationship. The sediment distribution showing first fining seaward and subsequent coarsening seaward from head to mouth, implies the two sediment sources in the paleo-estuary. The paleo-estuary of the Tarim Basin is very different from other representative estuaries. The most important distinction is that there are two adjacent estuaries joined by tidal flat onshore and by sandy and muddy subtidal flat in the sea at the same time, while the others only architecture model for the tide-dominated estuary. have one, So the Tazhong paleo-estuary shows a good

关键词： Tarim basin Silurian tide-dominated estuary tidal river tidal bar

A Raw Signal Simulator for Bistatic SAR

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Chinese Journal of Aeronautics 2009年第4期22卷 434-443页

作者： Xia Weijie,Zhou Jianjiang college of information {2. and technology,Nanjing University of Aeronautics and Astronautics,Nanjing 2.0016,china [a]college of information {2. and technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This article proposes a new efficient raw signal simulator for the bistatic synthetic aperture radar （SAR） based on 2. fast Fourier transform （FFT） to deal with cases of both ideal trajectory and trajectory deviation. It begins with analyzing the geometric configuration and the range history of the bistatic SAR in side-looking and squint modes of ideal trajectory as well as trajectory deviation. Then a detailed and mathematical study is conducted on the equivalence relation of bistatic-to-monostatic applications （BTMA） in the case of ideal trajectory and trajectory deviation. Also a set of formulas are derived for the equivalence relation between bistatic SAR and monostatic SAR on some reasonable assumptions. Therefore, the application of the simulation method based on the 2. FFT for the monostatic SAR can be extended to the case of bistatic SAR. Finally, the simulation results prove the validity of this method. By comparing the efficiency of the proposed method with that of the time domain method, it is shown that the former is a few orders of magnitude higher.

关键词： bistatic synthetic aperture radar raw signal simulation fast Fourier transform