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A condition-based maintenance policy for reconfigurable multi-device systems

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Advances in Manufacturing 2024年第2期12卷 252-269页

作者： Shu-Lian Xie Feng Xue Wei-Min Zhang Jia-Wei Zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) reconfigurable system remaining useful life Maintenance cost System reliability

Effects of forsythin extract in Forsythia leaves on intestinal microbiota and short-chain fatty acids in rats fed a high-fat diet

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Food Science and Human Wellness 2024年第2期13卷 659-667页

作者： Lanlan Gui Shaokang Wang Jing Wang Wang Liao Zitong Chen da Pan Hui Xia Guiju Sun Su Tian department of Nutrition and Food Hygiene School of Public HealthSoutheast UniversityNanjing 210009China Nanjing Municipal Center for disease Control and Prevention Nanjing 210003China department of Nutrition and Food Hygiene School of Public HealthHebei Medical UniversityShijiazhuang 050017China

Forsythia suspensa,belonging to the deciduous shrubs of the Luteaceae family,a traditional Chinese medicine,has effects of alleviating swelling,clearing heat,detoxification and promoting blood *** leaves of *** contain multiple chemical components and have a long history of use in folk medicines and health *** purpose of this study was to explore the effects of forsythin extract from *** leaves on intestinal microbiota and short-chain fatty acid(SCFA)content in rats with obesity induced by a high-fat *** extract in *** leaves increased the abundance of the intestinal microbiota,ameliorated intestinal microbiota disorders and inhibited the increase in total SCFA content in the intestinal tract in rats with obesity induced by a high-fat *** results suggested that forsythin extract in *** leaves may slow the development of obesity induced by a high-fat diet;thus,its active components and efficacy are worthy of further study.

关键词： Forsythin High-fat diet Intestinal microbiota Short-chain fatty acid(SCFA)

Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation

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Food Science and Human Wellness 2024年第1期13卷 421-433页

作者： Jingjing Liang Meina Zhang Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao College of Food Science and Engineering Northwest A&F UniversityYangling 712100China Xi'an GaoXin No.1 High School Xi'an 710065China

Plant-based fermentations provide an untapped source for novel biotechnological *** this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus *** were extracted from fermented and non-fermented *** and purified via dEAE-52 and Sephadex *** components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-Ir,HPGPC,HPAEC,SEM,GC-MS and *** results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) da to 1.87×10^(4) da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMr spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage ***,their immunomodulatory activities were evaluated with immunosuppressive ***-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields.

关键词： Lentinus edodes polysaccharide Lactobacillus fermentum fermentation Structural analysis Immunoregulatory activity Nuclear magnetic resonance

Single-cell rNA sequencing in juvenile idiopathic arthritis

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Genes & diseases 2024年第2期11卷 633-644页

作者： Xiwen Luo Xuemei Tang department of rheumatology and Immunology Children’s Hospital of Chongqing Medical UniversityChongqing 400014China Chongqing key Laboratory of Child Infection and Immunity Ministry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China

Juvenile idiopathic arthritis (JIA) is one of the most common chronic inflammatory rheumatic diseases in children,with onset before age 16 and lasting for more than 6 *** is a highly heterogeneous condition with various consequences for health and quality of *** some JIA patients,early detection and intervention remain *** a result,further investigation of the complex and unknown mechanisms underlying JIA is *** in technology now allow us to describe the biological heterogeneity and function of individual cell populations in *** this review,we hope to provide novel ideas and potential targets for the diagnosis and treatment of JIA by summarizing the current findings of single-cell rNA sequencing studies and understanding how the major cell subsets drive JIA pathogenesis.

关键词： Juvenile idiopathic arthritis Macrophage Macrophage activation syndrome Monocyte Single-cell rNA sequencing Synoviocyte T cell

Structural optimization design of semi-rigid base asphalt pavement using modulus matching criterion and multi-indicator range analysis

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 131-159页

作者： Zhihao Yang Linbing Wang dongwei Cao Yinghao Miao Hailu Yang china Airport Planning&design Institute Co. Ltd.Beijing 101312China department of road and Urban railway Engineering Beijing University of TechnologyBeijing 100124China national Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China School of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthensGA 30602USA china-road Transportation Verification&Inspection Hi-Tech Co. Ltd.Beijing 100088China

damage to semi-rigid base asphalt pavement is related to improper matching of the pavement structure *** study mainly focused on the modulus matching of structural layers and the development of a pavement structure optimization ***,the modulus loss of existing pavement structures was analysed,and a three-dimensional finite element model was established based on the existing ***,the influence of the modulus of each structural layer on the mechanical response indicators and fatigue life was *** on the results,a pavement structure design method using the smoothness of the stress-strain curve as the modulus matching criterion of the structural layers was *** it was found that a strain convex point was present and that the stress mutation between the structural layers was significant when the modulus matching of the pavement structure was ***,the evaluation indicators were divided into two groups,namely,mechanical indicators and fatigue life *** it was proposed an optimized pavement structure design method based on modulus matching and multi-indicator range ***,the optimal modulus combination of pavement structure was determined by this *** research systematically studied the influence of the modulus of each structural layer on the mechanical response and fatigue life of the pavement,and proposed the concept and specific executive criteria of modulus matching for the first ***,it also provided an effective optimization method for pavement structure design.

关键词： Stress-strain curve Modulus matching Structural optimization design Multi-indicator range analysis Fatigue life

Grain growth behavior and properties of high-entropy pseudobrookite(Mg,Co,Ni,Zn)Ti_(2)O_(5) ceramics

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Journal of Advanced Ceramics 2024年第6期13卷 757-768页

作者： Xiaohui Ma Jinyu Wu Lingyi Meng Jinfeng Zhang Heng Chen Liwen Yan Anran Guo Jiachen Liu key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin 300072China Xiamen key Laboratory of rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen 361021China

It is well known that the grain size of high-entropy ceramics is quite small owing to the sluggish diffusion effect. However, abnormal grain growth often occurs in high-entropy pseudobrookite ceramics, ultimately resulting in the formation of many abnormally grown grains with a grain size as large as 50 μm. To study this phenomenon, the grain growth behavior of high-entropy pseudobrookite ceramics was systematically investigated in this paper. The results demonstrate that the starting material powders first react with each other to form a high-entropy intermediate phase and calcined TiO_(2) powders (TiO_(2)-1100 ℃), and then as the sintering temperature increases, the formed high-entropy intermediate phase further reacts with TiO_(2)-1100 ℃ to form high-entropy pseudobrookite ceramics. Thus, in this system, in addition to the sluggish diffusion effect, the grain sizes of the high-entropy intermediate phase and TiO_(2)-1100 ℃ also affect the morphology of high-entropy pseudobrookite. Compared to nanosized TiO_(2), micron-sized TiO_(2) has a lower sintering activity. Therefore, the high-entropy intermediate phases (Mg,Co,Ni,Zn)TiO_(3) and TiO_(2)-1100 ℃ prepared with micron-sized starting materials exhibit lower grain sizes, finally resulting in the formation of high-entropy (Mg,Co,Ni,Zn)Ti_(2)O_(5) with small grain sizes. Moreover, nano-indentation and thermal conductivity tests were carried out on high-entropy (Mg,Co,Ni,Zn)Ti_(2)O_(5) with different morphologies. The results show that the hardness of high-entropy (Mg,Co,Ni,Zn)Ti_(2)O_(5) increases from 6.05 to 9.95 GPa as the grain size increases, whereas the thermal conductivity decreases from 2.091±0.006 to 1.583±0.006 W·m^(−1)·K^(−1). All these results indicate that high-entropy (Mg,Co,Ni,Zn)Ti_(2)O_(5) with a small grain size is a potential material for thermal protection.

关键词： grain size sluggish diffusion effect two-step solid phase process high-entropy intermediate phase high-entropy pseudobrookite ceramic

Potential risks of organic contaminated soil after persulfate remediation:Harmful gaseous sulfur release

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Journal of Environmental Sciences 2024年第1期135卷 1-9页

作者： Yuyang Long Zixiao Wu Xiaodong ding Jiansong Chen dongsheng Shen Jiali Shentu Cai Hui Zhejiang Provincial key Laboratory of Solid Waste Treatment and recycling Zhejiang Engineering Research Center of Non-ferrous Metal Waste RecyclingInstrumental Analysis CenterSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China Shangyu Yingtai Fine Chemical Co. Ltd.Shaoxing 312000China Hangzhou Ecological Environment Monitoring Center Hangzhou 310007China

Persulfate is considered a convenient and efficient remediation agent for organic contaminated ***,the potential risk of sulfur into the soil remediation by persulfate remains *** this study,glass bottles with different persulfate dosages and groundwater tables were set up to simulate persulfate remediation of organic pollutants(aniline).The results found sulfate to be the main end-product(83.0%–99.5%)of persulfate remediation after10 ***,H_(2)S accounted for 93.4%–99.4%of sulfur reduction end-products,suggesting that H_(2)S was the final fate of sulfur.H_(2)S was released rapidly after one to three days at a maximum concentration of 33.0 ppm,which is sufficient to make a person *** to the fitted curve results,H_(2)S concentration decreased to a safe concentration(0.15 ppm)after 20–85 ***,the maximum concentration of methanethiol reached 0.6 *** results indicated that secondary pollution from persulfate remediation could release harmful gases over a long ***,persulfate should be used more carefully as a remediation agent for soil contamination.

关键词： Gaseous sulfur release H_2S Long period potential risk Organic contaminated soil remediation Persulfate

Mathematical Modeling and a Multiswarm Collaborative Optimization Algorithm for Fuzzy Integrated Process Planning and Scheduling Problem

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Tsinghua Science and Technology 2024年第2期29卷 285-304页

作者： Qihao Liu Cuiyu Wang Xinyu Li Liang Gao State key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the study of Integrated Process Planning and Scheduling (IPPS) has become a hot topic in the current production field. However,when performing this integrated optimization,the uncertainty of processing time is a realistic key point that cannot be neglected. Thus,this paper investigates a Fuzzy IPPS (FIPPS) problem to minimize the maximum fuzzy completion time. Compared with the conventional IPPS problem,FIPPS considers the fuzzy process time in the uncertain production environment,which is more practical and realistic. However,it is difficult to solve the FIPPS problem due to the complicated fuzzy calculating rules. To solve this problem,this paper formulates a novel fuzzy mathematical model based on the process network graph and proposes a MultiSwarm Collaborative Optimization Algorithm (MSCOA) with an integrated encoding method to improve the optimization. different swarms evolve in various directions and collaborate in a certain number of iterations. Moreover,the critical path searching method is introduced according to the triangular fuzzy number,allowing for the calculation of rules to enhance the local searching ability of MSCOA. The numerical experiments extended from the well-known Kim benchmark are conducted to test the performance of the proposed MSCOA. Compared with other competitive algorithms,the results obtained by MSCOA show significant advantages,thus proving its effectiveness in solving the FIPPS problem.

关键词： Integrated Process Planning and Scheduling(IPPS) fuzzy processing time fuzzy completion time MultiSwarm Collaborative Optimization Algorithm(MSCOA)

Effect of intermittent joint distribution on the mechanical and acoustic behavior of rock masses

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Journal of rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1231-1244页

作者： Shuaiyang Fu Haibo Li Liwang Liu di Wu Ben Wang State key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic *** this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were *** results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the *** uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number ***,the wave velocity grows monotonically as the joint dip angle *** the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip *** wave velocity parallel to the joints is greater than that perpendicular to the *** the dip angle of joints remains unchanged,the UCS and wave velocity are positively *** the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity *** reveal the effect of the joint distribution on the velocity,a theoretical model was also *** to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation ***,a theoretical indicator(*** tensor)was adopted to analyze the variation of the wave velocity and UCS.

关键词： Stochastic joints Intrinsic cohesive zone model Uniaxial compressive strength(UCS) Wave propagation Fabric tensor