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Monitoring and diagnosis of complex production process based on free energy of Gaussian–Bernoulli restricted Boltzmann machine

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Journal of Iron and Steel Research(International) 2023年第5期30卷 971-984页

作者： qian-qian Dong Qing-ting qian Min Li gang Xu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

Online monitoring and diagnosis of production processes face great challenges due to the nonlinearity and multivariate of complex industrial processes.Traditional process monitoring methods employ kernel function or multilayer neural networks to solve the nonlinear mapping problem of data.However,the above methods increase the model complexity and are not interpretable,leading to difficulties in subsequent fault recognition/diagnosis/location.A process monitoring and diagnosis method based on the free energy of Gaussian-Bernoulli restricted Boltzmann machine(GBRBM-FE)was proposed.Firstly,a GBRBM network was established to make the probability distribution of the reconstructed data as close as possible to the probability distribution of the raw data.On this basis,the weights and biases in GBRBM network were used to construct F statistics,which represents the free energy of the sample.The smaller the energy of the sample is,the more normal the sample is.Therefore,F statistics can be used to monitor the production process.To diagnose fault variables,the F statistic for each sample was decomposed to obtain the Fv statistic for each variable.By analyzing the deviation degree between the corresponding variables of abnormal samples and normal samples,the cause of process abnormalities can be accurately located.The application of converter steelmaking process demonstrates that the proposed method outperforms the traditional methods,in terms of fault monitoring and diagnosis performance.

关键词： Process monitoring Fault diagnosis Gaussian–Bernoulli restricted Boltzmann machine Energy function Free energy Converter steelmaking production process

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Innate immune responses in RNA viral infection

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Frontiers of Medicine 2021年第3期15卷 333-346页

作者： qian Xu Yuting Tang gang Huang Divisions of Pathology and Experimental Hematology and Cancer Biology Cincinnati Children’s Hospital Medical CenterCincinnatiOH 45229USA Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

RNA viruses cause a multitude of human diseases,including several pandemic events in the past century.Upon viral invasion,the innate immune system responds rapidly and plays a key role in activating the adaptive immune system.In the innate immune system,the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral responses.Macrophages,dendritic cells,and natural killer cells are the principal innate immune components that exert antiviral activities.In this review,the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly summarized.Besides the main role of immune cells in combating viral infection,the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was discussed.This knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.

关键词： innate immune viral infection intercellular signaling metabolic changes epigenetic changes

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Effects ofmodulenumberand firing conditiononchargethermal safetyingunchamber

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Defence Technology（防务技术） 2022年第1期18卷 27-37页

作者： Huan-yu qian Yong-gang Yu Jing Liu School of Energy and Power Engineering Nanjing University of Science and Technology Narjing 21094 China Acudemny of Opto-Electroric China Electronis Technology Group Corporation(AOE CETC)Tianjin300308China

Thermal safety of modular charge which is fed into and retained in the chamber after gun fires consecutively is first investigated with cook-off method,A two-dimensional cook-off model of modular charge in gun chamber is established and the cook-off process of modular charge in gun chamber is numerically simulated.Then the effects of module number and firing condition on charge thermal safety are evaluated by researching the cook-off response characteristics of modules.The results show that under conditions of different module numbers the cook-off responses all occur on the module closest to the boundary of missile,and the single-base propellants located at the inner surface of cartridge ignite first.When the number of loaded module changes from 1 to 6,the cook-off response temperatures vary little,only in a small range of 478.1 K-482.4 K.The cook-off response times decrease logarithmically in the range of 211.25-166.7 s with the increasing length of residual air gap in gun chamber.The simulation results are well matched with the experimental data.Furthermore,different firing conditions have greatinfluence on the cook-off response time,minor influence on the initial response position and little in-fluence on the response temperature.Under the three conditions of consecutive 32 launches with 5 rounds/min,43 launches with 1 round/min,and 41 launches with different firing frequencies,the cook off response temperatures are 479.2 K,481.1 K and 479.9 K respectively and the response times are 709.25,211.2 s and 214.4 s respectively.The response position is near the middle area of the inner cartridge surface in the former condition and near the right area in the latter two conditions.

关键词： Thermal safety Modular charge Cook-off Firing condition

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Information Flow Security Models for Cloud Computing

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Computers, Materials & Continua 2020年第12期65卷 2687-2705页

作者： Congdong Lv Ji Zhang Zhoubao Sun Gang qian Nanjing Audit University Nanjing211815China Center for Data Science Courant Institute of Mathematical SciencesNew York UniversityNew York10011-8868USA

Cloud computing provides services to users through Internet.This open mode not only facilitates the access by users,but also brings potential security risks.In cloud computing,the risk of data leakage exists between users and virtual machines.Whether direct or indirect data leakage,it can be regarded as illegal information flow.Methods,such as access control models can control the information flow,but not the covert information flow.Therefore,it needs to use the noninterference models to detect the existence of illegal information flow in cloud computing architecture.Typical noninterference models are not suitable to certificate information flow in cloud computing architecture.In this paper,we propose several information flow models for cloud architecture.One model is for transitive cloud computing architecture.The others are for intransitive cloud computing architecture.When concurrent access actions execute in the cloud architecture,we want that security domain and security domain do not affect each other,that there is no information flow between security domains.But in fact,there will be more or less indirect information flow between security domains.Our models are concerned with how much information is allowed to flow.For example,in the CIP model,the other domain can learn the sequence of actions.But in the CTA model,the other domain can’t learn the information.Which security model will be used in an architecture depends on the security requirements for that architecture.

关键词： Cloud computing security information flow security noninterference noninterference models

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Experience and Challenge of Basic Education Development in China:Reflections on PISA 2018 Results

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Frontiers of Education in China 2022年第2期17卷 257-271页

作者： LI gang XIN Tao ZHAO qian Collaborative Innovation Center of Assessment for Basic Education Quality Beijing Normal UniversityBeijing 100875China

The outstanding performance of students in four Chinese provinces and municipalities in the Program for International Student Assessment(PISA)2018 is inextricably linked to local resource support,excellent education traditions,and ongoing curriculum and teaching reform.However,deepening education reform requires attention to existing challenges,including large inter-school gaps,the shortage of teachers in urban and rural areas,as well as students’heavy schoolwork burden and low level of well-being.Therefore,several policy suggestions are proposed accordingly:gaining insight into and developing higher quality and fairer education,pursuing effective actions of education reform,and exploring innovative pathways to address educational problems.

关键词： Program for International Student Assessment(PISA) basic education development reason interpretation policy analysis

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Production of biomass-derived monomers through catalytic conversion of furfural and hydroxymethylfurfural

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Green Chemical Engineering 2021年第2期2卷 158-173页

作者： hirong Yang Jing Zhang Gang qian Xuezhi Duan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237China

The synthesis of biomass-derived monomers has received great attention in recent years,motivated by the depletion of fossil fuels and environmental issues.Moreover,the intrinsic functionality within the biomass or biomass-derived chemicals has great potential to produce new types of monomers containing multiple acid or alcohol groups,thereby leading to materials with novel properties.Given their versatile functional groups and easy production from cellulose/hemicellulose,furfural and hydroxymethylfurfural were regarded as very important biomass-derived platform chemicals through which multiple monomers can be produced via heterogeneous catalysis.In the current review,recent development in heterogeneous catalysis for the production of 6 bio-based monomers,furfuryl alcohol,2,5-bis(hydroxymethyl)furan,2,5-bis-(hydroxymethyl)tetrahydrofuran,1,5-pentanediol,1,6-hexanediol,and 2,5-furandicarboxylic acid,from furfural and hydroxymethylfurfural is reviewed and summarized.The major challenge is how to efficiently and selectively convert specific functional group(s)in furfural and hydroxymethylfurfural during the production of these monomers.Additionally,catalyst stability issues need to be addressed due to necessity of using hot water as reaction medium and high tendency of carbonaceous deposit formation on catalyst surface.The current review mainly focuses on efforts of catalytic site design and modification,including selection of metal/support,use of synergy between metal and support,tuning metal size,use of inverse catalysts,adding catalytic promoters,constructing bimetallic sites,etc.,to realize efficient,selective and stable production of bio-based monomers from furfural and hydroxymethylfurfural.

关键词： Biomass-derived monomers Catalyst design Furfural Hydroxymethylfurfural Heterogeneous catalysis

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Towards a molecular understanding of the electronic metal-support interaction(EMSI)in heterogeneous catalysis

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Green Energy & Environment 2023年第3期8卷 619-625页

作者： Keng Sang Ji Zuo Xiangxue Zhang qianhong Wang Wenyao Chen Gang qian Xuezhi Duan State Key Laboratory of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai200237China

Tailoring the electronic metal-support interaction(EMSI)has attracted considerable interests as one of the most efficient approaches to improve both the activity and stability of metal catalysts in heterogeneous catalysis.In this viewpoint,we illustrate the methodology and relevant fundamentals on the disentanglement,characterization,and interpretation of EMSI.Under the choice of monometallic catalyst over inert support,a combination of optimal experiment design,multimodal techniques,in situ characterization,with a comprehensive understanding of the underlying measurement protocols is highly desirable for a reliable determination of EMSI.Accordingly,not only the d-band filling but also d-band energy within the EMSI should be taken into consideration for providing general principles to guide the electron-promoting catalytic reaction.

关键词： EMSI Disentanglement Characterization Interpretation d-band

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Target-oriented Q-compensated reverse-time migration by using optimized pure-mode wave equation in anisotropic media

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Petroleum Science 2023年第2期20卷 866-878页

作者： Shi-gang Xu qian-Zong Bao Zhi-Ming Ren Chang'an University School of Geological Engineering and GeomaticsDepartment of GeophysicsXi'anShaanxi710064China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing100028China

Research on seismic anisotropy and attenuation plays a significant role in exploration geophysics. To enhance the imaging quality for complicated structures, we develop several effective improvements for anisotropic attenuation effects in reverse-time migration (Q-RTM) on surface and vertical seismic profiling (VSP) acquisition geometries. First, to suppress pseudo-shear wave artifact and numerical instability of the commonly used anisotropic pseudo-acoustic wave equations, an optimized pure P-wave dispersion relation is derived and the corresponding pure-mode wave equation is solved by combining the finite-difference and Possion methods. Second, a simplified anisotropic pure-mode visco-acoustic wave equation (PVAWE) based on standard linear solid model is established. Third, a time-dispersion correlation strategy is applied to improve the modeling accuracy. Fourth, we extend a target-oriented scheme to anisotropic attenuated modeling and imaging. Instead of the conventional wavefield modeling and RTM, the proposed approach can extract available wavefield information near the target regions and produce high imaging resolution for target structures. Last, both anisotropic surface and VSP Q-RTMs are executed by combining optimized PVAWE, time-dispersion correlation and target-oriented algorithm. Modeling examples demonstrate the advantages of our schemes. Moreover, our modified Q-compensated imaging workflow can be regarded as a supplement to the classical anisotropic RTM.

关键词： Anisotropy Attenuation Reverse-time migration Wave equation Optimized algorithm Target-oriented

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Kinetics and mechanistic insights into the active sites of Au catalysts for selective propylene oxidation

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Nano Research 2023年第5期16卷 6220-6227页

作者： qianhong Wang Zhihua Zhang Keng Sang Wenyao Chen Gang qian Jing Zhang Xinggui Zhou Xuezhi Duan State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Identification of the catalytically active sites emerges as the prerequisite for an atomic-level comprehensive understanding and further rational design of highly efficient catalysts.Here,we demonstrate a kinetics strategy to identify the active sites of Au catalyst for the disentanglement of geometric and electronic effects on the selective oxidation of propylene to acrolein.Both the Ti-containing titanium-silicalite-1(TS-1)and Ti-free silicalite-1(S-1)were employed as supports to immobilize Au catalysts,which were investigated by a combination of multiple characterization,kinetics analysis,crystal structure modelling.The Au(111)sites are identified as the main active site for acrolein formation,while their electronic effects are highly relevant to the presence or absence of Ti.Moreover,propylene epoxide(PO)formation mainly involves the co-participation of Au and Ti sites,the proximity between Au and Ti sites is found to have less influences on PO formation in a certain distance.In comparison,acrolein is very likely to generate over Au(111)sites via the hydrogen-assisted O_(2) activation to oxygenated species for its oxidizing propylene.The insights gained here could guide the design and preparation of Au catalysts for selective propylene oxidation.

关键词： propylene oxidation Au catalysts active site geometric and electronic effects Au-Ti proximity

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雌激素对中枢能量代谢的影响及其机制的研究进展

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中华内分泌代谢杂志 2018年第3期34卷 263-268页

作者：李倩温俊平陈刚福建医科大学省立临床医学院福建省立医院内分泌科福州350001

女性性激素如雌激素，参与调控许多生理过程，如生长、发育、生殖和新陈代谢等。雌激素参与众多的生理过程具有受体依赖性，主要通过雌激素受体（ER）发挥作用。ER可分为ERα和ERβ两种类型，广泛分布于中枢和外周组织。近年来越来越多... 详细信息

女性性激素如雌激素，参与调控许多生理过程，如生长、发育、生殖和新陈代谢等。雌激素参与众多的生理过程具有受体依赖性，主要通过雌激素受体（ER）发挥作用。ER可分为ERα和ERβ两种类型，广泛分布于中枢和外周组织。近年来越来越多证据显示雌激素主要是在中枢神经系统尤其是下丘脑发挥各种生物学作用，表明中枢ER在雌激素调控的生理病理过程中起重要作用。本文将回顾雌激素在能量代谢方面的作用，尤其关注下丘脑部位的能量代谢作用，为生殖、能量代谢相关性疾病寻找中枢药物治疗的靶点。

关键词：雌激素能量代谢下丘脑

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