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1

Volcanic ash cloud detection from MODIS image based on CPIWS method

Liu L., Li Ch., Lei Y., Yin J., Zhao J.

Acta Geophysica

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2017

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Vol. 65, no. 1

151--163

EN

Volcanic ash cloud detection has been a difficult problem in moderate-resolution imaging spectroradiometer (MODIS) multispectral remote sensing application. Principal component analysis (PCA) and independent component analysis (ICA) are effective feature extraction methods based on second-order and higher order statistical analysis, and the support vector machine (SVM) can realize the nonlinear classification in low-dimensional space. Based on the characteristics of MODIS multispectral remote sensing image, via presenting a new volcanic ash cloud detection method, named combined PCA-ICA-weighted and SVM (CPIWS), the current study tested the real volcanic ash cloud detection cases, i.e., Sangeang Api volcanic ash cloud of 30 May 2014. Our experiments suggest that the overall accuracy and Kappa coefficient of the proposed CPIWS method reach 87.20 and 0.7958%, respectively, under certain conditions with the suitable weighted values; this has certain feasibility and practical significance.

2

Remote Sensing Monitoring of Volcanic Ash Clouds Based on PCA Method

Li Ch., Dai Y., Zhao J., Zhou S., Yin J., Xue D.

Acta Geophysica

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2015

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Vol. 63, no. 2

432--450

EN

Volcanic ash clouds threaten the aviation safety and cause global environmental effects. It is possible to effectively monitor the volcanic ash cloud with the aid of thermal infrared remote sensing technology. Principal component analysis (PCA) is able to remove the inter-band correlation and eliminate the data redundancy of remote sensing data. Taking the Eyjafjallajokull volcanic ash clouds formed on 15 and 19 April 2010 as an example, in this paper, the PCA method is used to monitor the volcanic ash cloud based on MODIS bands selection; the USGS standard spectral database and the volcanic absorbing aerosol index (AAI) are applied as contrasts to the monitoring result. The results indicate that: the PCA method is much simpler; its spectral matching rates reach 74.65 and 76.35%, respectively; and the PCA method has higher consistency with volcanic AAI distribution.

3

Short-term variation in zooplankton community from Daya Bay with outbreaks of Penilia avirostris

Li K., Yin J., Tan Y., Huang L., Song X.

Oceanologia

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2014

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No. 56 (3)

583--602

EN

The zooplankton community structure in bays fluctuates as a result of anthropogenic activities in such waters. We focused on the short-term variability of a zooplankton community and compared its differences at the outflow of a nuclear power plant (ONPP), in a marine cage-culture area (MCCA) and in unpolluted waters (UW) in the south-west part of Daya Bay from 28 April to 1 June 2001. Environmental factors and zooplankton abundance differed significantly among stations at ONPP, MCCA and UW: high temperatures and a high zooplankton abundance occurred at ONPP, while a high chlorophyll a concentration and a low zooplankton abundance prevailed in MCCA. Statistical analysis revealed that the zooplankton diversity and abundance could be reduced by the activity of the marine cage-culture in a short time. Penilia avirostris made up an important component of the zooplankton in the study area, its abundance ranging widely from 16 to 7267 indiv. m-3 from April to June and peaking at the ONPP outflow. The outbreak of P. avirostris probably resulted from the combined effects of favourable water temperature, food concentration and its parthenogenetic behaviour.

4

The selection of artificial corner reflectors based on RCS analysis

Li C., Yin J., Zhao J., Zhang G., Shan X.

Acta Geophysica

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2012

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Vol. 60, no. 1

43-58

EN

Artificial corner reflectors (ACRs) are widely applicable in monitoring terrain change via interferometric synthetic aperture radar (InSAR) remote sensing techniques. Many different types are available. The choice of the most appropriate ones has recently attracted scholarly attentions. Based on physical optics methods, via calculating the radar cross section (RCS) values (the higher the value, the better the detectability), the current study tested three ACRs, i.e., triangular pyramidal, rectangular pyramidal and square trihedral ACRs. Our calculation suggests that the square trihedral ACR produces the largest RCS but least tolerance towards incident radar ray’s deviation from optimal angle. The triangular pyramidal trihedral ACR is the most geometrically stable ACR, and has the highest tolerance towards incident radar ray’s deviation. Its RCS values, however, are the least of the three. Due to the high cost of deploying ACRs in the fields, the physical optics method seems to provide a viable way to choose appropriate ACRs.

5

Jurassic ammonites of the North Tibet

Yin J.

Volumina Jurassica

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2006

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Vol. 4, no. 1

223-224

EN

New collections from the northern Tibet allow the establishment of the Jurassic ammonite assemblages ranging from the Toarcian to Oxfordian times; they are the Early Toarcian: Cleviceras, Dactylioceras; Early and Middle Aalenian: Planammatoceras, Pleydellia, Erycites; Early Bajocian: Sonninia (Euhoploceras), Haplopleuroceras, Stephanoceras; Late Bathonian: Oxycerites, Homoeoplanulites Choffatia, Neuqueniceras; Middle Callovian: Oxycerites, Homoeoplanulites, Indospinctes (Elatmites), Reineckeites, and Late Oxfordian: Euaspidoceras, Peltomorphites assemblages. Taking into consideration the faunal distribution, facies and lithology four ammonite dispersal events are considered for being under eustatic control: the Sinemurian Angulaticeras dispersal marks the earliest Jurassic invasion into the south margin of the domain. The Cleviceras and Dactylioceras assemblage in association with black shales indicates a most striking Jurassic transgression during the Falciferum Zone time. The earliest Bajocian Sonninia (Euhoploceras), Haplopleuroceras, Stephanoceras assemblage would be more fully considered as one of the strongest candidates of the global sea-level rises. The latest Jurassic transgression took place in the Late Oxfordian, represented by the Euaspidoceras and Epipeltoceras assemblage; afterwards the Kimmeridgian regression sequence, indicated by brackish and none-marine bivalves ended the marine Jurassic record in the domain.

6

Electrode properties and microstructures of Ag-Sn based alloys used as anode in Li-ion batteries.

Kitano Y., Wada M., Sou T., Tanabe E., Fijikawa Y., Kitano A., Yin J., Sakai T.

Archives of Materials Science

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2005

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Vol. 26, nr 1-2

95-102

EN

Electron microscopic structures are investigated for the alloys, Ag52Sn48, Ag26Fe26Sn48 and Ag36.4Sb15.6Sn48. The alloy is used as the anode in the Li-ion batteries and gives a good performance in the properties such as current densities as well as cycling numbers of charge and discharge repetition. The alloys are synthesized by the mechanical alloying treatment. They are in the form of powder of a few žm in diameter. Each powder particle can be called a secondary particle. The secondary particle consists of a number of nano-sized crystallites. The alloy Ag52Sn48 consists of Sn and Ag3Sn, and the alloy Ag26Fe26Sn48 of Fe, Sn and Ag3Sn. These alloys are found to be porous. The porous structure would contribute to good performance of these alloys. The alloy Ag 36.4Sb15.6Sn48 consists of Sn, Ag3Sn and SbSn. The crystal structure of the SbSn is not cubic but rhombic. Volume expansion occurring at the rhombic SbSn to Li3Sb transformation is found to be only 20%. The small volume change during Li-insertion/Sn-extrusion would be an important factor for the good performance.

7

Development of electricity trading strategies under neta using evolutionary algorithms and game theory

Yin J., Li Y.

Systems Science

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2003

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Vol. 29, nr 3

139-151

EN

The energy crisis happening in California and problems emerging in other electricity power markets cross the world have led to more collusion and price tricks among energy companies and have motivated research into strategic gaming behaviors seen on power markets. Britain's power market trades physically and economically similar to that of California. Power generation companies in the U.K. make effort to attempt gaming strategies in trading. This paper explores a hybrid Game Theory and Evolutionary Computing method to study the possibility and impact of market manipulation in the U.K. power markets and hence to search for an optimal trading strategy for best profit.

8

The sensitive spectrophotometric method for the determination of cobalt with 2-(2-quinolinylazo)-5-diethylaminobenzoic acid

Wang L., Yang G., Hu Q., Yuan Z., Yin J.

Chemia Analityczna

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2003

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Vol. 48, No. 4

767-773

EN

A sensitive, selective and fast method for the determination of cobalt using 2-(2-quinoliny-lazo)-5-diethylaminobenzoic acid (QADEAB) as chromogenic reagent has been described. QADEAB reacts with Co(II) in acetate buffer (pH 4.0) and cetyl trimethylammonium bromide (CTMAB) media to form a violet complex of a molar ratio of cobalt to QADEAB equal 1:2. Its molar absorptivity at 630 nm is 1.4 x l O(5) L mol(-1) cm(-1). Beer's law is obeyed for cobalt concentration ranging from 0.01 to about 0.32 (ug ml(-1).

PL

Opisano szybką, czułą i selekwtywną metodę oznaczania kobaltu stosując jako odczynnik chelatujący kwas 2-(2-chinolinylazo)-5-dietyloaminobenzoesowy (QADEAB). Odczynnik ten reaguje z jonami Co(II) w buforze octanowym o pH 4,0 w obecności bromku cetylotrimetyloamoniowego (CTMAB) tworząc fioletowo zabarwiony kompleks o molowym stosunku Co(II): QADEAB wynoszącym 1:2. Molowy współczynnik absorpcji wynosi 1,4 x10(5) L mol(-1) cm(-1) przy długości fali 630 nm. Prawo Beerajest spełnione w zakresie od 0,01 do 0,32 (ig mL(-1). Opracowaną metodę zastosowano z dobrym rezulatatem do oznaczania kobaltu.