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The progress in the verification of key technologies for floating structures near islands and reefs

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Journal of Hydrodynamics 2021年第1期33卷 1-12页

作者： You-sheng Wu Jun Ding Xue-kang Gu Chun-yan Ji Xiong-bo zheng Guo-ping Zhou Dao-lin Xu Li Ma China Ship Scientific Research Center Wuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China Shanghai Merchant Ship Design and Research Institute Shanghai 201203China College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266000China

In 2019 a Scientific Research&Demonstration Platform was deployed near islands and reefs in South China Sea by a joint research group of 7 institutes and universities in *** is a simplified small model of a two-module semi-submersible-type *** test on site has continued for more than one and half years since then for long-term observations to validate the developed key technologies for design and behavior predictions of floating structures deployed near islands and *** integrated information system was set up to continuously collect and inspect the data of the encountered waves,structure responses,connector forces,mooring line forces,anti-corrosion status of the platform,the performance efficiencies of a floating breakwater nearby and a wave energy converter attached on the *** this paper,the status of the on-site measurements and validations of the key technologies are briefly described.

关键词： near islands and reefs inhomogeneous wave environment multi-module floating structures VLFS floating breakwater wave responses hydroelastic analysis predictions on-site measurements validation verification

Kinetics of hot metal desulfurization using CaO-SiO2-Al2O3-Na2O-TiO2 slag

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Journal of Iron and Steel Research International 2019年第10期26卷 1041-1051页

作者： kang-hui Zhang yan-ling Zhang Tuo Wu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Kinetics of hot metal desulfurization were studied using CaO-SiO2-Al2O3-Na2O-TiO2 slag in the range of 1400-1500℃on a laboratory *** results of kinetic experiments indicate that the desulfurization rate increases as the temperature,Al2O3 content,Na2O content,and TiO2 content increase and basicity increases from 1.01 to 1.75,but decreases when basicity increases from 1.75 to *** melting effect of slag is promoted as the temperature,Na2O content,and TiO2 content increase and Al2O3 content increases from 12.13 to 17.17 mass%,but worsened as basicity increases and Al2O3 content increases from 17.17 to 22.27 mass%.A kinetic model of hot metal desulfurization has been developed to calculate the mass transfer coefficient and the mass transfer resistance of sulfur in *** mass transfer coefficient of sulfur increases as the temperature,Al2O3 content,Na2O content,and TiO2 content increase and basicity *** mass transfer coefficients of sulfur were in the range of(5.02-23.78)×10^-7 m s^-*** activation energy was estimated to be 464.06 kJ mo1^-1 at the temperature from 1400 to 1450℃and 176.35 kJ mol-1 at the temperature from 1450 to 1500℃.The sulfur distribution at the slag-metal interface was observed using a mineral liberation *** result shows that the mass transfer of sulfur in slag is the controlling step at high temperature during the desulfurization process.

关键词： Hot metal desulfurization Kinetics Model Liquid area Kinetic parameter

Non-negative matrix factorization based unmixing for principal component transformed hyperspectral data

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Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 403-412页

作者： Xiu-rui GENG Lu-yan JI kang SUN Key Laboratory of Technology in Geo-spatial Information Processing and Application System Institute of Electronics Chinese Academy of Sciences Beijing 100190 China MOE Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University Beijing 100084 China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050000 China

Non-negative matrix factorization(NMF) has been widely used in mixture analysis for hyperspectral remote sensing. When used for spectral unmixing analysis, however, it has two main shortcomings:(1) since the dimensionality of hyperspectral data is usually very large, NMF tends to suffer from large computational complexity for the popular multiplicative iteration rule;(2) NMF is sensitive to noise(outliers), and thus the corrupted data will make the results of NMF meaningless. Although principal component analysis(PCA) can be used to mitigate these two problems, the transformed data will contain negative numbers, hindering the direct use of the multiplicative iteration rule of NMF. In this paper, we analyze the impact of PCA on NMF, and find that multiplicative NMF can also be applicable to data after principal component transformation. Based on this conclusion, we present a method to perform NMF in the principal component space, named ‘principal component NMF'(PCNMF). Experimental results show that PCNMF is both accurate and time-saving.

关键词： Non-negative matrix factorization(NMF) Principal component analysis(PCA) Endmember Hyperspectral

Effect of mechanical anisotropy on material removal rate and surface quality during polishing CdZnTe wafers

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Rare Metals 2011年第4期30卷 381-386页

作者： LI yan JIE Wanqi kang Renke GAO Hang State Key laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China Key Laboratory for Precision and Non-Traditional Machining Technology （Ministry of Education of China） Dalian University of Technology Dalian 116024 China

The mechanical characters of CdZnTe crystal were investigated by nanoscratch tests, and the effects of mechanical anisotropy on the material removal rate and surface quality were studied by polishing tests. There is a peak of frictional coefficient at the early stage of scratch, and increasing the vertical force will result in the increase of peak value correspondingly. The fluctuation phenomenon of frictional coefficient is generated at high vertical force. The lateral forces show the apparent twofold and threefold symmetries on （110） and （111） planes, respectively. To obtain high surface quality, low polishing pressure and hard direction （〈 T10 〉 directions on （110） plane and 〈 112 〉 directions on （111） plane） should be selected, and to achieve high material removal rate, high polishing pressure and soft direction （〈001〉 directions on （110） plane and 〈 121 〉 directions on （111） plane） should be selected.

关键词： cadmium compounds single crystals nanoscratch tests frictional coefficient material removal rate surface quality anisotropy

A novel diffusion model considering curvature radius at the bonding interface in a titanium/steel explosive clad plate

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 956-965页

作者： Hai-tao Jiang Qiang kang Xiao-qian yan National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing China Railway Materials Technologies Company Limited

This article introduces an element diffusion behavior model for a titanium/steel explosive clad plate characterized by a typical curved interface during the heat-treatment process. A series of heat-treatment experiments were conducted in the temperature range from 750℃ to 950℃, and the effects of heat-treatment parameters on the microstructural evolution and diffusion behavior were investigated by optical microscopy, scanning electron microscopy, X-ray diffraction analysis, and electron-probe microanalysis. Carbon atoms within the steel matrix were observed to diffuse toward the titanium matrix and to aggregate at the bonding interface at 850℃ or lower; in contrast, when the temperature exceeded 850℃, the mutual diffusion of Ti and Fe occurred, along with the diffusion of C atoms, resulting in the for- marion of Ti-Fe intermetallics （Fe2Ti/FeTi）. The diffusion distances of C, Ti, and Fe atoms increased with increasing heating temperature and/or holding time. On the basis of this diffusion behavior, a novel diffusion model was proposed. This model considers the effects of various factors, including the curvature radius of the curved interface, the diffusion coefficient, the heating temperature, and the holding rime. The experimental results show good agreement with the calculated values. The proposed model could clearly provide a general prediction of the elements＇ diffusion at both straight and curved interfaces.

关键词： explosive bonding metal cladding diffusion models interfaces heat treatment

EVALUATION OF INTERNATIONAL CLASSIFICATION CRITERIA (2002) FOR PRIMARY SJGREN'S SYNDROME IN CHINESE PATIENTS

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Chinese Medical Sciences Journal 2005年第3期20卷 190-193页

作者： yan Zhao Jian kang Wen-jie zheng Wei Zhou Xiao-ping Guo yan Gao Yi Dong Department of Rheumatology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 Department of Ophthalmology Beijing Hospital Beijing 100730

Objective To evaluate the sensitivity and specificity of international classification criteria （2002） for primary Sjogren＇s syndrome （pSS） and the role of lower lip biopsy in diagnosis of pSS in Chinese patients. Mothoda Patients who were diagnosed by the experts/rheumatologists as pSS during 1990-2002 from the Department of Rheumatology, Peking Union Medical College Hospital were retrospectively collected as experimental group. Patients who were diagnosed as non-pSS connective tissue diseases or non-connective tissue diseases served as control group. Those with a history of head-neck radiation, hepatitis C virus infection, AIDS, lymphoma, sarcoidosis, graft versus host disease （GVHD）, and anti-acetylcholine drug use were exempted. Both groups were required to complete questionnaires about symptoms such as dry eyes and dry mouth, and complete the objective tests of keratoconjunctivitis and xerostomia including Schirmer test, corneal staining, unstimulated salivary flow, sialography, lower lip biopsy, and antinuclear antibodies （including anti-SSA/SSB antibodies） test. Results A total of 330 pSS patients were included in experimental group and 185 non-pSS patients in control group. The mean age of both groups matched （47.8 ± 10.9 years vs. 46.2±13.6 years, P 〉 0.05）. The sensitivities of the criteria in pSS patients with lower lip biopsy and in pSS patients without lower lip biopsy were 89.2% and 87.2%, respectively; the overall sensitivity was 88.5%. The specificity was 97.3%. A total of 11.3% pSS patients with negative anti-SSA/SSB antibodies were diagnosed as pSS by lower lip biopsy. Coadwion The international classification criteria （2002） for pSS is feasible in Chinese patients. It has high sensitivity and specificity, and may serve as diagnosis criteria in routine clinical practice.

关键词： primary Sjogren's syndrome criteria classification

An algorithm for decomposing a polynomial system into normal ascending sets

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Science China Mathematics 2007年第10期50卷 1441-1450页

作者： Ding-kang WANG yan ZHANG Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

We present an algorithm to decompose a polynomial system into a finite set of normal ascending sets such that the set of the zeros of the polynomial system is the union of the sets of the regular zeros of the normal ascending sets. If the polynomial system is zero dimensional, the set of the zeros of the polynomials is the union of the sets of the zeros of the normal ascending sets.

关键词： zero decomposition, normal ascending set, polynomial system

Study of the electrochemical oxidation mechanism of formaldehyde on gold electrode in alkaline solution

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Chinese Chemical Letters 2013年第2期24卷 159-162页

作者： Rui-Wen yan Bao-kang Jin Department of Chemistry Anhui University

Received 7 November 2012 Received in revised form 10 December 2012 Accepted 31 December 2012 Available online 4 February 2013

关键词： Rapid-scan time-resolved FTIRFormaldehydeElectrochemical oxidation

Nonlocal Symmetries and Conservation Laws of Nonlocal Camassa-Holm Type Equations

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 909-920页

作者： Zhen-hua SHI Jing kang Lu yan Department of Mathematics Northwest University Center for Nonlinear Studies Northwest University Xingzhi College Xi'an University of Finance and Economics

The two-component μ-Camassa-Holm equation, the μ-Camassa-Holm equation and the modified μ- Camassa-Holm equation are three nonlocal integrable models. In this paper, it is shown that the two-component μ-Camassa-Holm equation and the μ-Camassa-Holm equation with a linear dispersion admit a kind of nonlocal symmetries, and the modified μ-Camassa-Holm equation does not have such kind of nonlocal symmetry. An number of conservation laws to the modified μ-Camassa-Holm equation and μ-Camassa-Holm equation are obtained.

关键词： Nonlocal symmetry conservation law the two-component μ-Camassa-Holm equation the modi-fied μ-Camassa-Holm equation the μ-Camassa-Holm equation