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A 2-Stage Strategy for Non-Stationary Signal Prediction and Recovery Using Iterative Filtering and Neural Network

Journal of Computer Science & Technology 2019年第2期34卷 318-338页

作者： Feng Zhou Hao-Min Zhou Zhi-hua yang li-hua yang School of Information Science Guangdong University of Finance and Economics Guangzhou 510320 China School of Mathematics Georgia Institute of Technology Atlanta GA 30332 U.S.A. Guangdong Province Key Laboratory of Computational Science Guangzhou 510275 China School of Mathematics Sun Yat-sen University Guangzhou 510275 China

Predicting the future information and recovering the missing data for time series are two vital tasks faced in various application *** are often subjected to big challenges,especially when the signal is nonlinear and nonstationary which is common in *** this paper,we propose a hybrid 2-stage approach,named IF2FNN,to predict(including short-term and long-term predictions)and recover the general types of time *** the first stage,we decompose the original non-stationary series into several“quasi stationary”intrinsic mode functions(IMFs)by the iterative filtering(IF)*** the second stage,all of the IMFs are fed as the inputs to the factorization machine based neural network model to perform the prediction and *** test the strategy on five datasets including an artificial constructed signal(ACS),and four real-world signals:the length of day(LOD),the northern hemisphere land-ocean temperature index(NHLTI),the troposphere monthly mean temperature(TMMT),and the national association of securities dealers automated quotations index(NASDAQ).The results are compared with those obtained from the other prevailing *** experiments indicate that under the same conditions,the proposed method outperforms the others for prediction and recovery according to various metrics such as mean absolute error(MAE),root mean square error(RMSE),and mean absolute percentage error(MAPE).

关键词： iterative filtering factorization machine neural network time series data recovery

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Fabrication of high nitrogen austenitic stainless steels with excellent mechanical and pitting corrosion properties

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 387-392页

作者： hua-bing li Zhou-hua Jiang yang Cao Zu-rui Zhang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

A series of high nitrogen austenitic stainless steels were successfully developed with a pressurized electroslag remelting furnace. Nitride additives and deoxidizer were packed into the stainless steel pipes, and then the stainless steel pipes were welded on the surface of an electrode with low nitrogen content to prepare a compound electrode. Using Si3N4 as a nitrogen alloying source, the silicon contents in the ingots were prone to be out of the specification range, the electric current fluctuated greatly and the surface qualities of the ingots were poor. The surface qualities of the ingots were improved with FeCrN as a nitrogen alloying source. The sound and compact macrostructure ingot with the maximum nitrogen content of 1.21wt% can be obtained. The 18Cr18Mn2Mo0.9N high nitrogen austenitic stainless steel exhibits high strength and good ductility at room temperature. The steel shows typical ductile-brittle transition behavior and excellent pitting corrosion resistance properties.

关键词： high nitrogen austenitic stainless steels electroslag remelting nitrogen alloying ductile-brittle transition pitting corrosion resistance

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A New Class of Multi-wavelet Bases: V-System

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Acta Mathematica Sinica,English Series 2012年第1期28卷 105-120页

作者： Chao huaNG li hua yang Dong Xu QI College of Mathematics and Computational Science Shenzhen UniversityShenzhen 518060P.R.China School of Mathematics and Computational Science Sun Yat-sen UniversityGuangdong Province Key Laboratory of Computational ScienceGuangzhou 510275P.RChina Faculty of Information Technology Macao University of Science and TechnologyMaeauP.R.China

The V-system is a complete orthogonal system of functions defined on the interval [0, 1], generated by finite Legendre polynomials and the dilation and translation of a function generator, which consists of a finite number of continuous and discontinuous functions. The V-system has interesting properties, such as orthogonality, symmetry, completeness and short compact support. It is shown in this paper that the V-system is essentially a special multi-wavelet basis. As a result, some basic properties of the V-system are established through the well-developed theory of multi-wavelets. From this point of view, more other V-systems are constructed.

关键词： Multi-wavelets V-system complete orthogonal system

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Hydrothermal Synthesis and Structural Characterization of Three-dimensional Metal-organic Framework [Zn_3(C_2H_2N_3)_2(C_7H_5O_2)_4]

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Chemical Research in Chinese Universities 2009年第1期25卷 1-4页

作者： SONG Zhe li Guang-hua YU yang SHI Zhan FENG Shou-hua College of Chemistry State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China

Hydrothermal reaction between mixed ligand（1,2,4-triazole and benzoic acid） and Zn（NO3）2·6H2O afforded a three-dimensional（3D） metal-organic framework Zn3（C2H2N3）2（C7H5O2）4（C2H2N3=1,2,4-triazole, C7H5O2=benzoic acid）. The compound was crystallized in the hexagonal system with space group R3： a=2.90234（9） nm, b=2.90234（9） nm, c=1.08597（5） nm, γ=120°, V=7.9222（5） nm^3, Mr=816.68, Dc=1.541 g/cm^3, Z=9, F（000）=3708, R=0.0636, and wR=0. 1777. Its structure consists of ZnN2O2 tetrahedron and ZnN204 octahedron, which are connected by 1,2,4-triazole and benzoic acid ligands to form a 3D framework with helical units. This compound forms an interpenetrated NbO topology. The compound was characterized by single-crystal X-ray diffraction, elemental analysis, FTIR spectra, and TGA measurements.

关键词： Hydrothermal synthesis Metal-organic framework 1,2,4-Triazole Benzoic acid Helical units

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Forward modeling to improve seismic reflection energy of a protective coal seam based on Zoeppritz equation

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Journal of China University of Mining and Technology 2008年第1期18卷 46-49页

作者： TAO Wen-peng DONG Shou-huax DONG Shou-hua li yang School of Resource and Geoscience China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

In seismic exploration for coal, seismic waves are very difficult to transmit downward because of high velocity protective layers, making the reflection information very hard to receive above ground. Based on the Snell law and the Zoeppritz equation, we studied the relationship between the incidence angle and reflection seismic wave energy using a forward model of level media. The result shows that the seismic wave energy has a sudden increase at the critical angle. Based on the energy propagation rule, using big offset to receive the seismic wave energy under a protective layer can effectively reduce its protection effect.

关键词： high velocity shielding layer Zoeppntz equation forward modeling

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Analysis of risk factors for polypoid lesions of gallbladder among health examinees

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World Journal of Gastroenterology 2012年第23期18卷 3015-3019页

作者： hua-li yang Hui-Fang Shen Yu Wang Xin-Gang Gu Jian-Min Qin Pei-Hao Yin Qi li Lei Kong li-li Hou Department of Ultrasonography Putuo Hospital Shanghai Univer- sity of Traditional Chinese Medicine Shanghai 200062 China Department of General Surgery Putuo Hospital Shanghai University of Traditional Chinese Medicine Shanghai 200062 China Department of Oncology Putuo Hospital Shanghai University of Traditional Chinese Medicine Shanghai 200062 China

AIM: To investigate the prevalence and risk factors of polypoid lesions of gallbladder (PLG) among the health examinees in the Shanghai region, China. METHODS: A total of 11 816 subjects who underwent health examinations in our hospital between August 2010 and February 2011 were analyzed retrospectively. Among them, there were 7174 men and 4642 women. PLG was diagnosed by the real-time ultrasonography. Those with the body mass index (BMI) ≥ 28 were considered to be obese. Blood biochemical indices were detected with the fully automatic biochemical analyzer and hepatitis B surface antigen (HBsAg) was tested by the automated enzyme immunoassay. The correlations between the prevalence of PLG and age, sex, BMI, serum cholesterol (T-Cho), triglycerides (TG),blood sugar, HBsAg, high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), gallstone and fatty liver were investigated. After univariate analysis of 11 variables, stepwise logistic regression analysis was performed to explore the risk factors of PLG. RESULTS: There was a significant difference in sex, T-Cho, HBsAg, HDL-C, LDL-C and fatty liver between the PLG-positive group and the PLG-negative group (332/163 vs 6842/4479, P = 0.003; 22/473 vs 295/11 026, P =0.013; 92/403 vs 993/10 328, P = 0.001; 47/448 vs 332/10 989, P = 0.001; 32/463 vs 381/10 940, P = 0.001; 83/412 vs 3260/8061, P = 0.001). No significant difference was found in the age, BMI, TG, blood sugar and gallstone between the two groups (47.3 ± 26 vs 45.1 ± 33, P = 0.173; 59/436 vs 1097/10 224, P = 0.102; 52/443 vs 982/10 339, P = 0.158; 17/478 vs 295/11 026, P = 0.26; 24/471 vs 395/10 926, P = 0.109). Logistic regression analysis showed that the sex, HBsAg and HDL-C were independent risk factors for the development of PLG in a descending order of HDL-C > HBsAg > sex. CONCLUSION: In healthy people, the male gender, positive HBsAg, and low HDL-C confer higher risks of PLG development.

关键词： Polypoid Gallbladder Risk factors UItraso-nography Health examination

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Solubility of wood-cellulose in liCl/DMAC solvent system

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Forestry Studies in China 2007年第3期9卷 217-220页

作者： He Jing liu Zhu li hua-yang Wang Guo-hua Pu Jun-wen College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

A liC1/DMAC solvent system was used to dissolve wood-cellulose with aims to broaden its application in preparing functional materials of modified wood-cellulose. We studied the dissolubility complexion of wood-cellulose in a liC1/DMAC solvent system, made sure of the important function of liC1 in a cellulose solvent, and further confirmed its dissolution mechanism via the measurement of infrared spectra of soluble products. The study results are as follows： first, liC1 salts, which can form intermediate complexes with cellulose, have played an important role in the liC1/DMAC solvent system, and their solubility performance is en- hanced by reducing the hydrogen bond effect between cellulose molecules; second, the non-aqueous solvent system is a better method for dissolving wood-cellulose in homogenous phase. As found in infrared spectra, the absorption intensity of hydroxyl groups （broad peaks： 3,400 cm^-1） decreased greatly in cellulose macromolecules. This is because the degree of association between the hydroxyl groups of cellulose macromolecules is reduced, due to the destruction of the hydrogen bonds. Lastly, wood-cellulose can be dissolved in a liC1/DMAC solvent thoroughly and efficiently, and can provide a better solvent system for homogeneous synthesis in the preparation of new functional materials via modified wood-cellulose.

关键词： wood-cellulose liC1/DMAC homogeneous solution solubility

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Synergistic Interaction and Gelation in Cationic Guar Gum-Sodium Alginate System

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 371-374页

作者： HeDong-bao lili-hua liQing yangXiao-zhen SchoolofResourcesandEnvironmentalSciences WuhanUniversityWuhan430072HubeiChina

The synergistic interaction between the cationic guar gum (the ammonium hydroxy-propyl-trimethyl chloride of guar gum) and sodium alginate has been studied. The effects of the mass ratio of them, mixed temperature, balk salt ion concentration, incubation time and pH value on gelation were investigated. It has been observed that there was a gel strength maximum when the mass ratio was 0.6, the mixed temperature was 70°C, the balk salt ion concentration was 1.0 mol·L?1, the incubation time was 30 min and the pH value was 8. Interaction between molecules of these two polysaccharides was investigated by FT-IR spectrometry. Key words cationic guar gum - sodium alginate - gelation - synergism CLC number O 629.12 Foundation item: Supported by the National Natural Science Foundation of China(29574173)Biography: He Dong-bao (1945-), male, Associate professor, research direction: modifying and gelating of natural polysaccharides.

关键词： cationic guar gum sodium alginate gelation synergism

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Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin Fang limin Wang Haoqin li Jiaxin Zhang yang Ding Pan Pan li Bo Peng hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe

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Primary study on imaging in transient ischemic attacks

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Chinese Medical Journal 2005年第21期118卷 1812-1816页

作者： LU Jie li Kun-cheng hua yang Department of Radiology Xuanwu Hospital Capital University of Medical Sciences Beijing 100053 China

Background Although transient ischemic attacks （TIA） is a clinical diagnosis, imaging findings are important for its diagnosis and treatment. This study evaluated the value and limitations of conventional CT, CT cerebral perfusion imaging and transcranial Doppler sonography （TCD） in patients with TIA. Methods Conventional CT, CT cerebral perfusion imaging and TCD were performed in 20 patients with TIA. After regular CT examination, d-0-second dynamic scans were performed on selected slice, while 40 ml of nonionic contrast materials was bolus-injected through antecubital vein with power injector. These dynamic images were processed with the perfusion software package on workstation. Cerebral blood flow （CBF） and time to peak （3~FP） were measured in specific regions of the brain. TCD was also performed in 20 patients with TIA. Comparative analysis was made on the basis of the results of conventional CT, CT cerebral perfusion imaging and *** In the 20 patients with TIA, conventional CT turned out to be normal. However, persisting abnormal perfusion changes corresponding to clinical symptoms were found in 13 cases with the prolonged TFP. The other 7 cases were normal. TFP of the affected side （ 11.6 ± 3.0） s was significantly prolonged （ t =4. 782 ,P 〈0. 01 ） in comparison with the contralateral side （8.8 ± 1.5 ） s. The difference in CBF was not statistically significant （t = 1. 912, P =0. 073） between the affected side [ （223.9 ±19.6） ml ·min^-1 ·L^-1 ] and the contralateral side [ （227.7 ± 19. 8） ml · min^-1· L^-1 ] . TCD revealed severe stenosis or occlusion of the carotid artery in 10 patients, arteriosclerosis in 6 patients, blood speed decrease in 2 patients, vasospasm in 1 patient. Conclusions Conventional CT can exclude intracerebral diseases. Perfusion CT provides valuable hemodynamic information and shows the extent of perfusion disturbances. TCD can demonstrate abnormalities of the involved arteries in patients with TIA. The combination of these three

关键词： transient ischemic attacks computerized tomography perfusion transcranial Doppler sonography

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