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Intelligent Diagnosis of Short Hydraulic Signal Based on Improved EEMD and SVM with Few Low-dimensional Training Samples

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 396-405页

作者： zhang Meijun TANG Jian zhang Xiaoming zhang jiaojiao Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing 210007 China Nanjing University of Aeronautics and Astronautics Nanjing 210007 China

The high accurate classification ability of an intelligent diagnosis method often needs a large amount of training samples with high-dimensional eigenvectors, however the characteristics of the signal need to be extracted accurately. Although the existing EMD（empirical mode decomposition） and EEMD（ensemble empirical mode decomposition） are suitable for processing non-stationary and non-linear signals, but when a short signal, such as a hydraulic impact signal, is concerned, their decomposition accuracy become very poor. An improve EEMD is proposed specifically for short hydraulic impact signals. The improvements of this new EEMD are mainly reflected in four aspects, including self-adaptive de-noising based on EEMD, signal extension based on SVM（support vector machine）, extreme center fitting based on cubic spline interpolation, and pseudo component exclusion based on cross-correlation analysis. After the energy eigenvector is extracted from the result of the improved EEMD, the fault pattern recognition based on SVM with small amount of low-dimensional training samples is studied. At last, the diagnosis ability of improved EEMD＋SVM method is compared with the EEMD＋SVM and EMD＋SVM methods, and its diagnosis accuracy is distinctly higher than the other two methods no matter the dimension of the eigenvectors are low or high. The improved EEMD is very propitious for the decomposition of short signal, such as hydraulic impact signal, and its combination with SVM has high ability for the diagnosis of hydraulic impact faults.

关键词： hydraulic impact fault improved EEMD end effect overshoot-undershoot SVM intelligent fault diagnosis short signal

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Pricing Credit Derivatives Under Fractional Stochastic Interest Rate Models with Jumps

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Journal of Systems Science & Complexity 2017年第3期30卷 645-659页

作者： zhang jiaojiao BI Xiuchun LI Rong zhang Shuguang School of Mathematical Sciences Xiamen UniversityXiamen 361005China School of Management University of Science and Technology of ChinaHefei 230022China

Based on the reduced-form approach, this paper investigates the pricing problems of default-risk bonds and credit default swaps(CDSs) for a fractional stochastic interest rate model with jump under the framework of primary-secondary. Using properties of the quasi-martingale with respect to the fractional Brownian motion and the jump technique in Park(2008), the authors first derive the explicit pricing formula of defaultable bonds. Then, based on the newly obtained pricing formula of defaultable bonds, the CDS is priced by the arbitrage-free principle. This paper presents an extension of the primary-secondary framework in Jarrow and Yu(2001).

关键词： CDS fractional Brownian motion primary-secondary framework reduced-form approach.

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Improved method to derive equivalent current systems from global MHD simulations

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Science China Earth Sciences 2014年第1期57卷 167-173页

作者： zhang jiaojiao WANG Chi TANG BinBin State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Derivation of equivalent current systems(ECS)from a global magnetospheric magnetohydrodynamics(MHD)model is very useful in studying magnetosphere-ionosphere coupling,ground induction effects,and space weather *** this study we introduce an improved method to derive the ECS from a global MHD model,which takes account of the obliqueness of the magnetic field *** comparing the ECS derived from this improved method and the previous method,we find that the main characteristics of the ECS derived from the two methods are generally consistent with each other,but the eastward-westward component of the geomagnetic perturbation calculated from the ECS derived from the improved method is much stronger than that from the previous *** then compare the geomagnetic perturbation as a function of the interplanetary magnetic field(IMF)clock angle calculated from the ECS derived from both methods with the *** comparison indicates that the improved method can improve the performance of the ***,it is found that the incomplete counterbalance of the geomagnetic effect produced by the ionospheric poloidal current and field-aligned current(FAC)contributes to most of the eastward-westward component of geomagnetic perturbation.

关键词： equivalent current systems global MHD model improved method

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Preparation and Characterization of High Content Paraffin Wax Microcapsules and Micro/Nanocapsules with Poly Methyl Methacrylate Shell by Suspension-Like Polymerization

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Chinese Journal of Chemistry 2017年第4期35卷 497-506页

作者： jiaojiao zhang Tianbo Zhao Yuqiao Chai Lili Wang Key Laboratory of Cluster Science of Ministry of Education Beijing Institute of Technology Beo'ing 100081 China

The suspension-like polymerization method is used to obtain poly methyl methacrylate （PMMA）/paraffin wax microcapsules and micro/nanocapsules with high core content. Particle size distribution （PSD） analysis indicates that the average particle size of microcapsules is 94 μm, and the size of micro/nanocapsules ranges in 0.1-19 μm. Differential scanning calorimetry （DSC） and thermalgravimetric analysis （TGA） results show that the fabricated paraffin contents in microcapsules and micro/nanocapsules are as high as 89.5 wt% and 80~2 wt%, respectively with good thermal stability. Thermal cycling tests justify that both the microcapsules and micro/nanocapsules have good thermal reliability with respect to the changes in their thermal properties after 1000 thermal cycling. This work pro- vides a novel method to prepare microcapsules and micro/nanocapsules with high core content which may benefit further study on thermal energy storage.

关键词： microcapsules micro/nanocapsules suspension-like polymerization poly methyl methacrylate paraffin wax

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DNA: From Carrier of Genetic Information to Polymeric Materials

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Transactions of Tianjin University 2019年第4期25卷 301-311页

作者： jiaojiao zhang Feng Li Dayong Yang Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE) School of Chemical Engineering and TechnologyTianjin University

Research has shown that the DNA molecule can not only store genetic information but also serve as a polymeric biomolecule for the fabrication of functional materials. The unique precise molecular recognition capability and sequence programmability, combined with its good biocompatibility and biodegradability, impart the DNA molecule considerable potential for use in the construction of multifunctional materials. Depending on the composition, DNA-based materials have been generally categorized into pure DNA materials that are entirely composed of DNA and hybrid DNA materials that are composed of DNA and other functional compositions. Recently, we have developed a series of DNA-based materials that can be applied in diagnosis and therapy, and this review summarizes the relative work. Although challenges still exist regarding the real applications of DNA-based materials such as the high cost of DNA, the difficulty in scale-up, and the low resistance to nuclease, we believe that these drawbacks will be overcome with the development of technology, and new opportunities will emerge in the fi eld of diagnosis and treatment.

关键词： DNA materials DNA nanotechnology Biomedicine

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Ternary deep eutectic solvents catalyzed D-glucosamine self-condensation to deoxyfructosazine: NMR study

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Green Energy & Environment 2021年第2期6卷 261-270页

作者： Pengfei Liu Christian Marcus Pedersen jiaojiao zhang Rui Liu Zhenzhou zhang Xianglin Hou Yingxiong Wang Shanxi Engineering Research Center of Biorefinery Instiute of Coal ChemistryChinese Academy of Sciences27 South Taoyucn Road Taiyun030001China Center of Materials Science and Optoeletronics Engineering University of Chinese Academy of SciencesBejing100049China Department of Chemistny University of CopenhagenUniversitetsparken 5DK-2100 CopenhagenDenmark School of Chemical Engineering Zhengzhou University Zhengzhou450001China

Ternary deep eutectic solvents(TDESs) comprising choline chloride(Ch Cl), glycerol and L-arginine were synthesized as catalysts and solvents for the conversion of D-glucosamine(GlcNH_(2)) into deoxyfructosazine(DOF). The interactions between these three components in the prepared TDESs were studied by ^(1)H-,^(35)Cl-NMR spectra and ^(1)H diffusion-ordered spectroscopy(DOSY) measurements. The chemical shift changes of active hydrogen in the ^(1)H-NMR spectra of TDES system and widening of signals in the^(35)Cl-NMR spectra confirmed the hydrogen bonding interaction between the components, which was further supported by the decrease of diffusion coefficients(D) of the TDES components according to ^(1)H DOSY measurements. The influences of reaction temperature and L-arginine content in the TDESs on the yield of DOF were also studied. The experimental results have shown that when the molar ratio of Ch Cl, glycerol, and L-arginine was 1:2:0.1, DOF was the major product with a yield of 22.6% at 90℃ for 120 min. The chemical shift titration indicated that the carboxyl group of L-arginine in the TDES is the catalytical active site, so the mechanism of the catalytic reaction between Glc NH_(2) and the TDES was proposed. Moreover, a reaction intermediate, dihydrofructosazine, was identified in the self-condensation reaction of Glc NH_(2) by an in situ ^(1)H NMR technique.

关键词： Ternary deep eutectic solvents Hydrogen bonding NMR D-glucosamine Deoxyfructosazine

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Radiation build-up and dissipation in Raman random fiber laser

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Science China(Information Sciences) 2024年第1期67卷 254-260页

作者： Shengtao LIN Zinan WANG jiaojiao zhang Pan WANG Han WU Yifei QI Key Laboratory of Optical Fiber Sensing and Communications University of Electronic Science and Technology of China College of Electronics and Information Engineering Sichuan University

Raman random fiber laser(RRFL) is a complex physical system that arises from the distributed Raman amplification and the intrinsic stochasticity of fiber *** analysis of the underlying lightwave kinetics at steady state has been the focus of considerable ***,the transient state,such as the RRFL build-up and dissipation,is particularly important for revealing the lightwave interaction ***,we investigate for the first time the RRFL dynamics at the transient state and track the RRFL temporal and spectral evolution theoretically and ***,with the contribution of random distributed feedback,RRFL build-up exhibits continuous Verhulst logistic growth curves without cavity-related features,which is significantly different from the step-like growth curve of conventional fiber ***,the radiation build-up duration is inversely related to the pump power,and the spectral evolution of the RRFL undergoes two phases,i.e.,from spectral density increase to spectral *** the steady state to the pump switch-off state,the RRFL output power dissipates immediately,and the remaining Stokes lightwave from the Rayleigh scattering will gradually disappear after one round *** work provides new insights into the transient dynamic features of the RRFL.

关键词： random fiber laser stimulated Raman scattering transient phenomenon nonlinear optics biological growth dynamics

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Incidence Tendency Analysis on Type 2 Diabetes in 4 Asian Countries—China,Malaysia,Singapore,and Thailand,1990–2019

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China CDC weekly 2021年第52期3卷 1113-1117页

作者： Wenhui Shi Qiqi Wang jiaojiao zhang Jingwen zhang Feng Tan Shicheng Yu Division of Non-communicable Diseases and Elderly Health Management Chinese Center for Disease Control and PreventionBeijingChina Office of Epidemiology Chinese Center for Disease Control and PreventionBeijingChina Institute of Infectious Diseases Beijing Center for Disease Control and PreventionBeijingChina Shijiazhuang Finance Bureau of Hebei Province ShijiazhuangHebeiChina Division of Academic Publishing Management Chinese Center for Disease Control and PreventionBeijingChina.

Summary What is already known about this topic?Roughly 80%of the global disease burden caused by diabetes comes from low-and-middle income countries,and 60%of diabetics are located in Asia;6 of the top 10 countries with the highest prevalence of diabetes are in *** is added by this report?Compared with 1990,the growth rate of the standardized incidence rate of type 2 diabetes in 2019 in China was significantly lower than that of the entire world,while Malaysia,Singapore.

关键词： Diabetes income Singapore

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Postharvest Variations of Rice Physicochemical Traits and Volatile Compounds under Granary Conditions During Long-Time Storage

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Rice science 2023年第2期30卷 92-95,I0007-I0009页

作者： HU Hao LIU Xingquan HE Yukai JIN Jiande WU Fenghua HUANG Shiwen zhang jiaojiao College of Food and Health Zhejiang Agriculture and Forest UniversityHangzhou 311300China China National Rice Research Institute Hangzhou 310006China Zhejiang Province Grain Reserve Management Co.LTD Hangzhou 310006China

Rice quality is influenced by many factors,viz.,temperature,humidity,atmosphere and storage *** uncover quality variations of rice after postharvest,we estimated the physicochemical properties and volatile compounds of an indica rice Zhongzheyou 8 under granary conditions(20ºC-25ºC in summer and 10ºC-15ºC in other seasons)for three years.

关键词： Traits humidity harvest

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Mitochondrial protein IF1 is a potential regulator of glucagon-like peptide(GLP-1) secretion function of the mouse intestine

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Acta Pharmaceutica Sinica B 2021年第6期11卷 1568-1577页

作者： Ying Wang jiaojiao zhang Xinyu Cao Yaya Guan Shuang Shen Genshen Zhong Xiwen Xiong Yanhong Xu Xiaoying zhang Hui Wang Jianping Ye Henan Key Laboratory of Immunology and Targeted Therapy Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory MedicineSchool of Laboratory MedicineXinxiang Medical UniversityXinxiang 453003China Shanghai Diabetes Institute Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai 201306China School of Forensic Medicine Xinxiang Medical UniversityXinxiang 453003China Central Laboratory Shanghai Sixth People's Hospital East CampusShanghai Jiao Tong UniversityShanghai 201306China

IF1(ATPIF1) is a nuclear DNA-encoded mitochondrial protein whose activity is inhibition of the F1Fo-ATP synthase to control ATP ***1 activity remains unknown in the regulation of GLP-1 *** this study,IF1 was examined in the diet-induced obese mice using the gene knockout(If1-KO) *** mice gained more body weight on a high fat diet without a change in food *** tolerance was impaired,but the oral glucose tolerance was improved through an increase in GLP-1 *** KO mice exhibited an improved intestine structure,mitochondrial superstructure,enhanced mitophagy,reduced apoptosis and decreased adenine nucleotide translocase 2(ANT2) protein in the intestinal epithelial cells together with preserved gut *** data suggest that GLP-1 secretion was enhanced in the obese If1-KO mice to preserve glucose tolerance through a signaling pathway of ANT2/mitochondria/L-cells/GLP-1/***1 is a potential mitochondrial target for induction of GLP-1 secretion in L-cells.

关键词： GLP-1 ATPIF1 ANT2 L-cells Mitophagy Microbiota Glucose tolerance Insulin resistance

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