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Viability decision of linear discrete-time stochastic systems with probability criterion

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控制理论与应用（英文版） 2009年第3期7卷 297-300页

作者： Wansheng TANG jun zheng Jianxiong zhang Institute of Systems Engineering Tianjin University Tianjin 300072 China

In this paper, the optimal viability decision problem of linear discrete-time stochastic systems with probability criterion is investigated. Under the condition of sequence-reachable discrete-time dynamic systems, the existence theorem of optimal viability strategy is given and the solving procedure of the optimal strategy is provided based on dynamic programming. A numerical example shows the effectiveness of the proposed methods.

关键词： Stochastic systems Decision-making Probability criterion Dynamic programming

A room-temperature magnetic semiconductor from a Co-Fe-Nb-B metallic glass

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 94-99页

作者： Yu-zhang Jiao Dmitry VLouzguine-Luzgin Ke-Fu Yao zheng-jun zhang Na Chen Laboratory for Advanced Materials Processing Technology(MOE) State Key Laboratory of New Ceramics and Fine ProcessingSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials(MOE) Schoolof Materials Science and EngineeringTsinghua UniversityBeijing 100084China Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan Mathematics for Advanced Materials-OIL National Institute of Advanced Industrial Science and Technology(AIST)Sendai 980-8577Japan

Magnetic semiconductors with Curie temperatures higher than room temperature show potential for developing spintronic devices with combined data processing and storage functions for next-generation computing *** this study,we present an n-type Co_(19.8)Fe_(8.6)Nb_(4.3)B_(6.0)O_(61.3) magnetic semiconductor with a high Curie temperature of~559 *** magnetic semiconductor has a room-temperature resistivity of~2.10×10^(4)Ωcm and a saturation magnetization of~76 emu/cm^(3).The n-type Co_(19.8)Fe_(8.6)Nb_(4.3)B_(6.0)O_(61.3)magnetic semiconductor was deposited on p-type silicon to form a heterojunction,exhibiting a rectifying *** results provide the design principles for discovering high Curie temperature magnetic semiconductors with determined conduction types,which would play an essential role in realizing nonvolatile spin-based transistors that break free from the confines of currently established Si-based information technology.

关键词： magnetic semiconductor ferromagnetic metallic glass high Curie temperature

Vestigial suppresses apoptosis and cell migration in a manner dependent on the level of JNK-Caspase signaling in the Drosophila wing disc

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Insect Science 2021年第1期28卷 63-76页

作者： Wen-Min Fan Dan Luo jun-zheng zhang Dan Wang Jie Shen Department of Entomology and MOA Lab for Pest Monitoring and Green Control China Agricultural UniversityBeijingChina

The Decapentaplegic(Dpp)and Wingless(Wg)signal pathways play important roles in numerous biological processes in *** Drosophila vestigial(vg)gene is selectively required for wing imaginal disc cell proliferation,which is essential for the formation of the adult wing and halter structures,and is regulated by Dpp and Wg *** a Drosophila invasion model of wing epithelium,we showed herein that inhibition of Dpp or Wg signaling promoted cells to migrate across the cell lineage restrictive anterior/posterior(A/P)compartment *** downstream of both Dpp and Wg signaling,vg can block cell migration induced by loss of either *** addition,suppression of vg is sufficient to induce cell migration across the A/P *** analysis revealed potential downstream genes involved in the cell migration after suppressing vg in the wing *** further demonstrated that the c-jun N-terminal kinase(JNK)signaling promoted cell migration induced by vg suppression by upregulating Caspase *** together,our results revealed the requirement ofVg for suppressing cell migration and clarified how developmental signals collaborate to stabilize cells along the compartment boundary.

关键词： Caspase cell migration Dpp Drosophila wing disc JNK vestigial Wg

Synthesis temperature dependence of morphologies and properties of cobalt oxide and silicon nanocrystals

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Frontiers of Computer Science 2011年第3期5卷 311-321页

作者： Akimasa KOJI Javed IQBAL Rong-Hai YU zheng-jun zhang Department of Materials Science and Engineering Tsinghua University Beijing 100084 China Department of Metallurgy and Ceramics Science Tokyo Institute of Technology 2-12-10okayama Meguro-ku Tokyo 152-8552 Japan

Cobalt and cobalt oxide nanocrystals were synthesized on Si substrates from aqueous cobalt nitrate [Co（NO3）2·6H2O] powder via chemical vapor deposition method. Scanning electron microscope, field emission scanning electron microscope, and transmission electron microscope observations show different morphologies, such as continuous films, nano-bars, nano-dices, and nano-strings, depending on the synthesis temperature. The crystal structure characterization was conducted using X- ray diffraction methods. Furthermore, the properties of the samples were characterized using Raman spectroscopic analysis and vibrating sample magnetometer. The morphology change was discussed in terms of synthesis environments and chemical interactions between cobalt, oxygen, and silicon.

关键词： cobalt oxide nanostructure temperature dependence magnetic property

Myogenic differentiation of mesenchymal stem cells for muscle regeneration in urinary tract

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Chinese Medical Journal 2013年第15期126卷 2952-2959页

作者： YANG Bin zheng jun-hua zhang Yuan-yuan Tongji Univ Sch Med Dept Urol Shanghai Peoples Hosp 10 Shanghai 200072 Peoples R China Wake Forest Univ Sch Med Wake Forest Inst Regenerat Med Winston Salem NC 27101 USA

Objective This article was to review the current status of adult mesenchymal stem cells transplantation for muscle regeneration in urinary tract and propose the future prospect in this field. Data sources The data used in this review were mainly obtained from articles listed in Medline and PubMed （2000- 2013）. The search terms were ＂mesenchymal stem cells＂, ＂bladder＂, ＂stress urinary incontinence＂ and ＂tissue engineering＂. Study selection Articles regarding the adult mesenchymal stem cells for tissue engineering of bladder and stress urinary incontinence were selected and reviewed. Results Adult mesenchymal stem cells had been identified and well characterized in human bone marrow, adipose tissue, skeletal muscle and urine, and demonstrated the capability of differentiating into smooth muscle cells and skeletal muscle ceils under myogenic differentiation conditions in vitro. Multiple preclinicat and clinical studies indicated that adult mesenchymal stem cells could restore and maintain the structure and function of urinary muscle tissues after transplanted, and potentially improve the quality of life in patients. Conclusions Smooth or skeletal myogenic differentiation of mesenchymal stem cells with regenerative medicine technology may provide a novel approach for muscle regeneration and tissue repair in urinary tract. The long-term effect and safety of mesenchymal stem cell transplantation should be further evaluated before this approach becomes widely used in patients.

关键词： mesenchymal stem cell tissue engineering regenerative medicine bladder stress urinary incontinence

Development and application of an intelligent thermal state monitoring system for sintering machine tails based on CNN-LSTM hybrid neural networks

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Journal of Iron and Steel Research International 2025年第1期32卷 52-63页

作者： Da-lin Xiong Xin-yu zhang zheng-wei Yu Xue-feng zhang Hong-ming Long Liang-jun Chen Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling Anhui University of TechnologyMa’anshan243002AnhuiChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina School of Computer Science Anhui University of TechnologyMa’anshan243032AnhuiChina

Real-time prediction and precise control of sinter quality are pivotal for energy saving,cost reduction,quality improvement and efficiency enhancement in the ironmaking *** advance,the accuracy and comprehensiveness of sinter quality prediction,an intelligent flare monitoring system for sintering machine tails that combines hybrid neural networks integrating convolutional neural network with long short-term memory(CNN-LSTM)networks was *** system utilized a high-temperature thermal imager for image acquisition at the sintering machine tail and employed a zone-triggered method to accurately capture dynamic feature images under challenging conditions of high-temperature,high dust,and *** feature images were then segmented through a triple-iteration multi-thresholding approach based on the maximum between-class variance method to minimize detail loss during the segmentation *** the advantages of CNN and LSTM networks in capturing temporal and spatial information,a comprehensive model for sinter quality prediction was constructed,with inputs including the proportion of combustion layer,porosity rate,temperature distribution,and image features obtained from the convolutional neural network,and outputs comprising quality indicators such as underburning index,uniformity index,and FeO content of the *** accuracy is notably increased,achieving a 95.8%hit rate within an error margin of±*** the system is applied,the average qualified rate of FeO content increases from 87.24%to 89.99%,representing an improvement of 2.75%.The average monthly solid fuel consumption is reduced from 49.75 to 46.44 kg/t,leading to a 6.65%reduction and underscoring significant energy saving and cost reduction effects.

关键词： Sinter quality Convolutional neural network Long short-term memory Image segmentation FeO prediction

A High-Order Numerical Method Based on Legendre Polynomial Approximation for Fourth-Order Eigenvalue Problem in Cylinder Domain

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Journal of Mathematical Research with Applications 2025年第2期 195-219页

作者： jun zhang Jihui zheng Fangying SONG Computational Mathematics Research Center Guizhou University of Finance and Economics School of Mathematical Sciences Guizhou Normal University School of Mathematics and Stastistics Fuzhou University

In this work, an efficient spectral method is proposed to solve the fourth-order eigenvalue problem in cylinder domain. Firstly, the key point of this method is to decompose the original model into a kind of decoupled two-dimensional eigenvalue problem by cylindrical coordinate transformation and Fourier series expansion, and deduce the crucial essential pole conditions. Secondly, we define a kind of weighted Sobolev spaces, and establish a suitable variational formula and its discrete form for each two-dimensional eigenvalue problem. Furthermore, we derive the equivalent operator formulas and obtain some prior error estimates of spectral theory of compact operators. More importantly, we further obtained error estimates for approximating eigenvalues and eigenfunctions by using two newly constructed projection operators. Finally,some numerical experiments are performed to validate our theoretical results and algorithm.

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An efficient conversion model between acceleration and pseudo-acceleration response spectra considering effects of magnitude,distance,and site class

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 15-30页

作者： Liu zheng Zhao Yan-Gang zhang Haizhong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China Faculty of Agriculture Yamagata University1-23Wakaba-machiTsuruoka-shiYamagata 997-8555Japan

Both acceleration and pseudo-acceleration response spectra play important roles in structural seismic ***,only one of them is generally provided in most seismic ***,many studies have attempted to develop conversion models between the acceleration response spectrum(SA)and the pseudo-acceleration response spectrum(PSA).Our previous studies found that the relationship between SA and PSA is affected by magnitude,distance,and site ***,we developed an SA/PSA model incorporating these ***,this model is suitable for cases with small and moderate magnitudes and its accuracy is not good enough for cases with large *** paper aims to develop an efficient SA/PSA model by considering influences of magnitude,distance,and site class,which can be applied to cases not only with small or moderate magnitudes but also with large *** this purpose,regression analyses were conducted using 16,660 horizontal seismic records with a wider range of *** magnitude of these seismic records varies from 4 to 9 and the distances vary from 10 to 200 *** ground motions were recorded at 338 stations covering four site *** comparing them with existing models,it was found that the proposed model shows better accuracy for cases with any magnitudes,distances,and site classes considered in this study.

关键词： acceleration response spectrum pseudo-acceleration response spectrum magnitude distance site class

Characterization of size-resolved aerosol hygroscopicity and liquid water content in Nanjing of the Yangtze River Delta

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Journal of Environmental Sciences 2025年第5期151卷 26-41页

作者： Youling Jiang Yan Ma jun zheng Nan Ye Cheng Yuan School of Environmental Science and Engineering Nanjing University of Information Science and TechnologyNanjing 210044China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 210044China School of Emergency Management Nanjing University of Information Science&TechnologyNanjing 210044China

Aerosol hygroscopicity and liquid water content(ALWC)have important influences on the environmental and climate effect of *** this study,we measured the hygroscopic growth factors(GF)of particles with dry diameters of 40,80,150,and 200 nm during the wintertime in *** the GF-derived hygroscopicity parameter(κ_(gf))and ALWC increased with particle size,but displayed differing diurnal variations,withκ_(gf)peaking around the midday,while ALWC peaking in the early ***,ammonium and oxygenated organic aerosols(OOA)were found as the chemical components mostly strongly correlated with ALWC.A closure study suggests that during midday photo-oxidation and nighttime high ALWC periods,theκof organic aerosols(κ_(org))was underestimated when using previous ***,we re-constructed parameterizations forκ_(org)and the oxidation level of organics for these periods,which indicates a higher hygroscopicity of photochemically formed OOA than the aqueous OOA,yet both being much higher than the generally assumed OOA ***,in a typical high ALWC episode,concurrently increased ALWC,nitrate,OOA as well as aerosol surface area and mass concentrations were observed under elevated ambient *** strongly indicates a coupled effect that the hygroscopic secondary aerosols,in particular nitratewith strong hygroscopicity,led to large increase in ALWC,which in turn synergistically boosted nitrate and OOA formation by heterogeneous/aqueous *** interaction may represent an important mechanism contributing to enhanced formation of secondary aerosols and rapid growth of fine particulate matter under relatively high RH conditions.

关键词： Aerosol hygroscopicity Aerosol liquid water content Photo-oxidation Aqueous/heterogeneous reactions