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Two-level Hierarchical Clustering Analysis and Application

厦门大学学报（自然科学版） 2002年第S1期41卷 283-284页

作者： HU Hui-rong, WANG Zhou-jing (department of Automation, xiamen university,{2., china)

Hierarchical clustering analysis based on statistic s is one of the most important mining algorithms, but the traditionary hierarchica l clustering method is based on global comparing, which only takes in Q clusteri ng while ignoring R clustering in practice, so it has some limitation especially when the number of sample and index is very large. Furthermore, because of igno ring the association between the different indexes, the clustering result is not good & true. In this paper, we present the model and the algorithm of two-level hierarchi cal clustering which integrates Q clustering with R clustering. Moreover, becaus e two-level hierarchical clustering is based on the respective clustering resul t of each class, the classification of the indexes directly effects on the a ccuracy of the final clustering result, how to appropriately classify the inde xes is the chief and difficult problem we must handle in advance. Although some literatures also have referred to the issue of the classificati on of the indexes, but the articles classify the indexes only according to their superficial signification, which is unscientific. The reasons are as follow s: First, the superficial signification of some indexes usually takes on different meanings and it is easy to be misapprehended by different person. Furthermore, t his classification method seldom make use of history data, the classification re sult is not so objective. Second, for some indexes, its superficial signification didn’t show any mean ings, so simply from the superficial signification, we can’t classify them to c ertain classes. Third, this classification method need the users have higher level knowledge of this field, otherwise it is difficult for the users to understand the signifi cation of some indexes, which sometimes is not available. So in this paper, to this question, we first use R clustering method to cluste ring indexes, dividing p dimension indexes into q classes, then adopt two-level clustering meth

关键词： data mining clustering hierarchical clustering R clustering Q clustering

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Preparation and Electromechanical Properties of PVDF Matrix Piezoelectric Composites Containing Highly Oriented BaTiO_3 Whiskers

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Journal of Materials Science & Technology 2004年第4期20卷 441-444页

作者： Xuetao LUO, Lifu CHEN, Xiaojun CHEN and Qianjun HUANGdepartment of Materials Science and Engineering, xiamen university,{2., china Dept. of Mat. Sci. and Eng. Xiamen Univ. Xiamen 361005 China

The piezoelectric composites containing highly oriented BaTiO3 whiskers as active phase and PVDF as matrix have been prepared by micro-hole extrusion and orientation in carried fibers. The morphology of oriented BaTiO3 whiskers and microstructure of the composites were observed by SEM. As for its electromechanical properties, it is found that the dielectric constant, piezoelectric constant and remnant of polarization in the BaTiO3 whisker-PVDF composite are considerably higher than that in the BaTiO3 powders-PVDF composite, while the loss factors follow the opposite trend. For the BaTiO3 whisker-PVDF composite, the values of ε, d33 and Pr parallel to the whisker orientation (normal specimen) are much higher than that perpendicular to the whisker orientation (parallel specimen). The significant effects of the connective passages of active phase on electromechanical properties of the piezoelectric composites has also been investigated.

关键词： Piezoelectric composite BaTiO3 whiskers Electromechanical properties Polarization Connective passages

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Qeochemical behaviour of iodine in Jiulong River Estuary

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Acta Oceanologica Sinica 1989年第1期8卷 91-99页

作者： Guo Jinbao and Peng Zhen department of Oceanography, xiamen university, {2., china

Dissolved iodine species and the relationship between its distribution and salinity in Jiulong River estuarine water have been determined. It has been found that the total iodine, iodate and iodide are positive linear with salinity. This indicates that dissolved iodine species (IO-3 and I- ) in estuarine water .how conservative behaviour. The river water contains 2. 40μg/1 as iodide and less than 1. 0μg/1 as iodate, and iodide is the predominant species. Whereas the sea water contains 39. 4μg/1 as iodate and 4. 00μg/1 as iodide, and iodate is the dominant form. The distribution of dissolved iodine in pore water, as a function of depth, has been studied. Iodine in pore water occurs as iodide. The apparent fluxes of soluble iodine from the sediment to the overlying water in the estuary have been determined. The values are 2. 4 (15℃) and 2.μmol/(m2.d) (30℃) respectively.

关键词： Qeochemical behaviour of iodine in Jiulong River Estuary

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Preliminary study on nanodiatom in the Taiwan Strait

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Acta Oceanologica Sinica 2000年第1期19卷 91-98页

作者： Guo Jian Huang Bangqin Cheng Zhaodi Hong Huasheng (1. department of Biology, xiamen university,{2., china. 2. Research Lab of SEDC on Marine Ecological Environment, Environmental Science Research Center, xiamen university,{2., china. department of Biology Xiamen University Xiamen 361005 China Res. Lab. SEDC Mar. Ecol. Environ. Environ. Science Research Center Xiamen University Xiamen 361005 China

The preliminary study on nanodiatom in the Taiwan Strait was carried out using transmission electron microscopy (TEM) in February 1995. Thirty-three species of nanodiatom (2. μm) were identified, among which, 6 were new recorders in china. The dominant species were Minidiscus comicus Takano and Thalassiosira tenera Proschdinae -- Lavrenko in the northern Taiwan Strait (NTS), Minidiscus trioculatus (F. J. R. ) Hasle and Natvicula climacospheniae both in the southern Taiwan Strait (STS). Abundance of nanodiatom was much more than that of microdiatom (>2. μm), and the abundance of nanodiatom in NTS is higher than that in STS. The highest abundance of nanodiatom was at the depth of 10 m of N33o in NTS, while at the depth of 2. m of S105 in STS. The vertical distribution of nano- and micro-diatom of NCI showed that the peak was at the depth of 30 m.

关键词： Nanediatom Taiwan Strait abundance species diversity

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Marine　diatoms　of　the　Xisha　Islands，　South　china　Sea　Mastogloia　Thw，　Ex，　Wm，　Smith：　species　of　Group　Ellipticae

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Acta Oceanologica Sinica 1995年第1期14卷 59-71页

作者： Liu Shicheng(department of Biology, xiamen university,{2., china)

Seventeen species of diatoms of the genus Mastogloia are recorded. For selected species, the external andinternal valve structures are investigated under LM, TEM and SEM microscopes. M. sp. (M. af. cocconeiformis)is d... 详细信息

关键词： Mastogloia Ellipticae diatom fine structure

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Sectional distribution of salinity and its indication of Kuroshio'sintrusion in the southern Taiwan Strait and northeastern South china Sea late summer, 1994

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Acta Oceanologica Sinica 1999年第2期18卷 225-236页

作者： Hu Jianyu Liang Hongxing and Zhang Xuebin 1. Institute of Subtropical Oceanography, xiamen university, xiamen 3.1005,{2. 2. Fujian Institute of Oceanology, xiamen 361012.{2. (Received June 3, 1998 accepted August 8, 1998) Inst. of Subtropical Oceanography Xiamen University Xiamen 361005 China Fujian Institute of Oceanology Xiamen 361012 China

Using the CTD data investigated at about 330 stations in the southern Taiwan Strait, the northeastern South china Sea and their adjacent seas in August and September of 1994, this paper anayses the sectional distributions of salinity in 10 selected sections and discusses the possibility of the Kuroshio's intrusion into the northeastern South china Sea and the southern Taiwan Strait. The results show that: as the main stream of Kuroshio passes by the northern Luzon Strait during the survey period, the 'Kuroshio-influenced water' with some hydrological features of the Kuroshio may extend through the Luzon Strait to the sea areas near both the Dongsha Islands and the Taiwan Shoal of the southern Taiwan Strait.

关键词： Sectional distribution of salinity Kuroshio's intrusion late summer southern Taiwan Strait northeastern South china Sea

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Laser-induced Thermal Index Grating and Its Relaxation Effectin Polyatomic Molecular Materials

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光电子.激光 1989年第2期 105-106页

作者： Zhou Haiguang Chen ShuchaoMembers of the Physics Society of china, Members of the OpticsSociety of chinaAddress: Physics {2., xiamen university, xiamen, chinaTel: 2.393, xiamen, china

The laser beam transmission can produce the laser-induced thermal index grating in polyatomic molecular materials. This grating effect has only a qualitative description in past published papers. In this paper we present a qualitative study of laser-induced thermal index grating and its relaation in polyatomic molecular *** optics bistability and degenerate four wave mixing arrangements, we have observed thermal index grating and its relaxation in nematic liquid crystales. The experiments were performed in solid, nematic and liquid phases of these materials. These experiments in solid phase of liquid crystals was performed and related physical mechanism was also discussed for the firsttime to our knowledge.

关键词： Laser-induced Thermal Index Grating and Its Relaxation Effectin Polyatomic Molecular Materials

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Characteristic analysis for a polynomial-like iterative equation

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Chinese Science Bulletin 1998年第3期43卷 192-196页

作者： Janusz Matkowski 1 and ZHANG Weinian 2.1. department of mathematics, Technical {2., 43_300 Bielsko_Biala, Poland 2. department of mathematics, Sichuan Union {2., Chengdu 610064, china department of mathematics Technical University Bielsko-Biala Poland department of mathematics Sichuan Union University Chengdu China

In the light of Euler’s idea for differential equations,a polynomial_like n _order iterative equation is discussed through analyzing its characteristic polynomial. An unproved result is verified rigorously for the fi... 详细信息

关键词： iterative dynamics functional equation characteristic.

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Ultrastructure　study　of　the　diatom──Ⅱ．Synedra，Cyclophora，Plagiogramma，Opephora，Fragilaria　and　Pseudostaurosira

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Acta Oceanologica Sinica 1994年第4期13卷 579-588页

作者： Liu Shicheng (department of Biology, xiamen university,{2., china)

Six genera and thirteen species of diatoms are collected from the intertidal zone of Xisha Islands,Hainan Province, and observated under the transmitted light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). of them, four new species, and one genus are newly recorded (marked).They are: Synedra cyclophoroides sp. nov., Cycolophora tenuis, Plagiogramma parva sp. nov., Plagiogramme pandurata sp. nov., P. atomus, P. reimeri, Opephora elliptica sp. nov. O. martyi, O. olsenii,O. sp. Fragilaria brevistriata v. elliptica; F. construens and Pseudostaurosira brevistriata.

关键词： Diatom Ultrastructure Synedra Cyclophora Plagiogramma Opephora Fragilaria Pseudostaurosira.

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Dynamics of DOC of euphotic layer in the Taiwan Strait─—Diurnal variation of large range

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Acta Oceanologica Sinica 1998年第4期17卷 483-493页

作者： Peng Xingyue, (department of Biology, xiamen university,{2., china)Hong Huasheng and Shang Shaoling (Environmental Science Research Center, Research Lab of SEC of Marine Ecological Environment, xiamen university,{2., china) department of Biology Xiamen University Xiamen 361005 China Environ. Science Research Center Res. Lab. SEC of Mar. Ecol. Environ. Xiamen University Xiamen 361005 China

Three oceanographic investigations from 1994 to 1995 in the Taiwan Strait show that the dissolved organic carbon (DOC) in the euphotic layer has a large-scale diurnal variation [2.~ 4 mg/dm3], and its amplitude range has spatial and seasonal changes. Generally, the DOC in the euphotic layer is higher at day than that at night. According to the diurnal variations, DOC can be divided into two parts: new DOC and old DOC. The content of new DOC varies rapidly every day but the content of old DOC does not. Though there is still not a good explanation for this diurnal variation of DOC, it may call attention to the study of organic carbon dynamics, especially the DOC primary production of phytoplankton, the DOC utilization of bacteria, and the flux of DOC in coastal sea water.

关键词： DOC,the Taiwan Strait dynamics diurnal variation

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