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Rapid Path Extraction and Three-Dimensional Roaming of the Virtual Endonasal Endoscope

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Chinese Journal of Electronics 2021年第3期30卷 397-405页

作者： wang yudong HAN Jing PAN Junjun wang Jing CAO Yi ZHU Li LUO Yanlin School of Artificial Intelligence Beijing Normal University State Key Laboratory of Virtual Reality Technology and Systems Beihang University Institute of Applied Physics and Computational Mathematics Department of Otolaryngology Head and Neck Surgery Peking University Third Hospital

Compared with traditional endonasal endoscope, Virtual endonasal endoscope(VEE) is a computerized alternative solution with the advantages of being non-invasive, affordable, no perforation, low risk of infection, and high degree of sensitivity. A Central path extraction algorithm based on Pre-planning of the roaming area(CPE-PRA) is proposed to extract the central path of the nasal cavity model efficiently. And a B-spline curve fitting algorithm based on Relative center deviation(RCD)is introduced to fit a smooth curve to the extracted path,so that the virtual camera could have both a steady turning speed and a broad vision. A series of comparison tests were conducted to evaluate the effectiveness and efficiency of the proposed algorithms.

关键词： virtual instrumentation Virtual endonasal endoscope RCD rapid path extraction nasal cavity model medical image processing VEE feature extraction path planning CPE-PRA splines (mathematics) B-spline curve fitting algorithm computerized alternative solution roaming area relative center deviation virtual camera Central path extraction algorithm curve fitting endoscopes surgery medical robotics three-dimensional roaming

A cross-species co-functional gene network underlying leaf senescence

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Horticulture Research 2023年第1期10卷 288-298页

作者： Moyang Liu Chaocheng Guo Kexuan Xie Kai Chen Jiahao Chen yudong wang Xu wang Shanghai Collaborative Innovation Center of Agri-Seeds/School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China

The complex leaf senescence process is governed by various levels of transcriptional and translational *** features of the leaf senescence process are similar across species,yet the extent to which the molecular mechanisms underlying the process of leaf senescence are conserved remains *** used experimental approaches permit the identification of individual pathways that regulate various physiological and biochemical processes;however,the large-scale regulatory network underpinning intricate processes like leaf senescence cannot be built using these ***,we discovered a series of conserved genes involved in leaf senescence in a common horticultural crop(Solanum lycopersicum),a monocot plant(Oryza sativa),and a eudicot plant(Arabidopsis thaliana)through analyses of the evolutionary relationships and expression patterns among *** analyses revealed that the genetic basis of leaf senescence is largely conserved across *** also created a multi-omics workf low using data from more than 10000 samples from 85 projects and constructed a leaf senescence-associated co-functional gene network with 2769 conserved,high-confidence ***,we found that the mitochondrial unfolded protein response(UPR^(mt))is the central biological process underlying leaf ***,UPR^(mt) responds to leaf senescence by maintaining mitostasis through a few cross-species conserved transcription factors(***13)and metabolites(***).The co-functional network built in our study indicates that UPR^(mt) figures prominently in cross-species conserved ***,the results of our study provide new insights that will aid future studies of leaf senescence.

关键词： network functional conserved

Study on Wall Temperature Distribution of Oscillating Tube

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Journal of Thermal Science 2009年第3期18卷 246-252页

作者： Dapeng HU Peiqi LIU Wenjing ZHAO Che ZHU yudong wang Yuqiang DAI Jiupeng ZOU Institute of Chemical Engineering Dalian University of Technology Dalian 116012 Liaoning China Xin Jiang Xin Jie co. Ltd Wulumuqi 830011 Xinjiang China

The wall temperature distribution and heat transfer process of the oscillating tube have been investigated in thispaper using both numerical simulation and experimental method. The wall temperature of oscillating tube increasesrapidly in the inlet and then decreases slowly, moreover, the rally phenomenon of wall temperature nearthe closed end is observed. With the increase of jet flow frequency, the highest wall temperature increases and thelocation of that moves towards the inlet. The velocity of pressure wave in the oscillating tube almost remainsconstant even its intensity changes. The quantity of heat transfer between the gas and inner wall of the oscillatingtube determines the wall temperature of every location, and the pressure wave disturbance can cause the heattransfer quantity change. Each pressure wave has its own disturbance range. The wall temperature distribution canbe explained by the change of pressure wave intensity and its disturbance time. Besides, the step and rally of walltemperature are discussed, which shows that the conditions of heat transfer can be improved due to intersection orreflection of pressure waves.

关键词： thermal separator oscillating tube pressure wave numerical simulation.

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Investors’perspective on forecasting crude oil return volatility:Where do we stand today?

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Journal of Management Science and Engineering 2022年第3期7卷 423-438页

作者： Li Liu Qianjie Geng Yaojie Zhang yudong wang School of Finance Nanjing Auditing UniversityNanjing211815China School of Economics and Management Nanjing University of Science and TechnologyNanjing210094China

In this paper,we review studies of oil volatility prediction from a new perspective:that of investors who require economic evaluations of forecasting *** results indicate that no single volatility model outperforms all of the competing models,of which GARCH and realized volatility models are the most *** studies evaluate forecasting performance using two criteria:value at risk and hedging *** instability and model uncertainty are technical issues that affect out-of-sample *** studies assess volatility forecasts from the perspectives of portfolio management and derivative *** oil volatility can predict economic variables and the asset pricing implications of oil volatility for financial markets are important topics that require attention.

关键词： Oil volatility Out-of-sample forecasting Economic predictability Evaluation criteria

Relaxor behavior of (1-x)Pb(Mg_(1/3)Nb_(2/3))O_3-xPbTiO_3 ceramics

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Chinese Science Bulletin 2009年第7期54卷 1267-1274页

作者： WU NingNing SONG XueMei HOU yudong ZHU ManKang wang Chao YAN Hui Key Laboratory of Advanced Functional Materials of the Ministry of Education Beijing University of Technology Beijing 100124 China

In the present work, the phase transitions and relaxor behavior of (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT, x = 0.2―0.4) ferroelectric ceramics have been investigated by means of X-ray diffraction, di-electric spectroscopy, the P-E hysteresis loop measurements and Raman scattering techniques. Structural analysis revealed that with the increase of PbTiO3 content, PMN-PT ceramics experienced a gradual phase transition process from rhombohedral to tetragonal. It is usually believed that such kinds of phase transitions resulted in the linear decrease of relaxation degree. Surprisingly, our analysis of the dielectric spectra revealed that the indicator of the degree of diffuseness γ reached the maximum value near morphotropic phase boundary (MPB) (x = 0.32), then decreased with the further increase of PbTiO3 content. The large dielectric relaxor feature near MPB may be attributed to the for-mation of ordered nanodomains, resulting from complex coexisting nanostructures. Further, the P-E hysteresis loop measurements and Raman analysis of the B-site cation order correlated well with the dielectric measurement results. It was found that the hysteresis loop squareness Rsq received the minimum value while the inverse of the value of full wide of half maximum (FWHM) of A1g mode reached the maximum value at MPB composition, which showed similar trends to γ.

关键词： PbTiO3陶瓷弛豫行为铅含量磁滞回线测量中性粒细胞铁电陶瓷材料 Raman 细胞疗法

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To jump or not to jump:momentum of jumps in crude oil price volatility prediction

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Financial Innovation 2022年第1期8卷 1647-1677页

作者： Yaojie Zhang yudong wang Feng Ma Yu Wei School of Economics and Management Nanjing University of Science and TechnologyXiaolingwei 200Xuanwu DistrictNanjing 210094China School of Economics and Management Southwest Jiaotong UniversityChengduChina School of Finance Yunnan University of Finance and EconomicsKunmingChina

A well-documented finding is that explicitly using jumps cannot efficiently enhance the predictability of crude oil price *** address this issue,we find a phenomenon,“momentum of jumps”(MoJ),that the predictive ability of the jump component is persistent when forecasting the oil futures market ***,we propose a strategy that allows the predictive model to switch between a benchmark model without jumps and an alternative model with a jump component according to their recent past forecasting *** volatility data are based on the intraday prices of West Texas *** results indicate that this simple strategy significantly outperforms the individual models and a series of competing strategies such as forecast combinations and shrinkage methods.A mean–variance investor who targets a constant Sharpe ratio can realize the highest economic gains using the MoJ-based volatility *** findings survive a wide variety of robustness tests,including different jump measures,alternative volatility measures,various financial markets,and extensive model specifications.

关键词： Oil futures market Volatility forecasting Momentum of jumps Model switching Portfolio exercise

Adaptive Control for Lateral Motion of Reusable Launch Vehicle Using Retrospective Cost Estimator 36

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Adaptive Control for Lateral Motion of Reusable Launch Vehic...

Active-transporting of charge-reversal Cu(Ⅱ)-doped mesoporous silica nanoagents for antitumor chemo/chemodynamic therapy

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作者： Shicong Dai Quanjun Liu Ying wang Zhang Ren yudong wang Changwan Min Science and Technology on Space Physics Laboratory

ISBN: (纸本)9781538629185

An in-flight aerodynamic coefficient estimation method is proposed for nonlinear lateral motion of reusable launch vehicle via retrospective cost adaptive control *** estimated aerodynamic coefficient is then utilized for adaptive controller switch to cope with unexpected polarity change of LCDP（Lateral Control Departure Parameter） ***,the nonlinear lateral dynamics of a reusable launch vehicle rewritten to a form where the lateral moments are expressed linearly by aerodynamic coefficients related to ***,the identification problem is converted to an adaptive control problem for a virtual system to track the angular velocity of the *** adaptive control problem is then solved by utilizing retrospective cost adaptive control *** estimation error dynamics is analyzed and an update law is *** on attitude three degree-of-freedom nonlinear model along a standard trajectory shows the performance of the proposed estimator to capture time-varying LCDP with multiple zero crossing in flight and the performance of the adaptive switch controller to yield converging lateral motion.

关键词： Lateral Control Departure Parameter Nonminimum-Phase Reusable launch vehicle Retrospective Cost Adaptive Control

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Chinese Chemical Letters 2024年第7期35卷 400-406页

作者： Zhaomin Tang Qian He Jianren Zhou Shuang Yan Li Jiang yudong wang Chenxing Yao Huangzhao Wei Keda Yang Jiajia wang School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China Shulan International Medical College Zhejiang Shuren UniversityHangzhou 310015China Department of Laboratory Medicine Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China

Fe-based Fenton agents can generate highly reactive and toxic hydroxyl radicals(·OH)in the tumor microenvironment(TME)for chemodynamic therapy(CDT)with high ***,the low pH environment and insufficient endogenous hydrogen peroxide(H_(2)O_(2))of the highly efficient Fenton reaction limits its practical application in ***,a Cu(Ⅱ)-doped mesoporous silica nanoagent(Cu-MSN)with excellent dispersity was successfully *** loaded with doxorubicin(DOX)and ascorbate(AA),Cu-MSN@DA was coated with active targeting ligand folic acid(FA),dimethyl maleic an-hydride(DMMA)and carboxymethyl chitosan(CMC)to obtain an active transporting nanoagent(FCDC@Cu-MSN@DA)with tunable charge-reversal property,which is more adaptable to the pH value of TME than Fe-based Fenton agents,and can self-supply exogenous H_(2)O_(2)by ascorbate to produce more toxic·OH to trigger the apoptosis of cancer ***,the high level of glutathione(GSH)in TME can reduce Cu(Ⅱ)to Cu(I)by Fenton-like reaction,increasing the generation rate of·OH and relieving tumor antioxidant *** supply of exogenous H_(2)O_(2)significantly enhanced the synergistic effect of CDT by oxidative *** with DOX-induced cell apoptosis,this novel nanoagent FCDC@Cu-MSN@DA can achieve maximum therapeutic efficacy,creating a new model of safe and effective tumor treatment with high specificity.

关键词： Cu(Ⅱ)-doped Ascorbate Hydrogen peroxide Charge-reversal Oxidative damage

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On Figure and Ground in Dunhuang Mural Painting

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艺术史与艺术哲学

艺术史与艺术哲学 2020年 243-263页

作者： wang yudong Guangzhou Academy of Fine Arts

Art historical narratives of Chinese medieval murals tend to begin with what is available to our perception,taking as their starting point the finished object that is the end result of a chain of artistic practices.

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