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Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber

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Fluid Dynamics & Materials Processing 2024年第5期20卷 989-1014页

作者： Yi Tu yuan Wu Yu zeng Hunan University of Arts and Sciences Hunan Key Laboratory of Distributed Electric Propulsion Vehicle Control TechnologyChangde415000China Liaoning Provincial Key Laboratory of Aircraft Ice Protection AVIC Aerodynamics Research InstituteShenyang110034China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic *** Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent *** study employs a validated Computational Fluid Dynamics(CFD)approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing ***,the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the *** research findings indicate that,within the considered flow range,reducing the nozzle specific areaφfrom 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%.This enhancement increases the air circulating rate,thereby intensifying convective heat transfer within the SAI ***,the reduction inφalso leads to a significant increase in the required bleed air pressure and a higher entropy generation rate,indicating lower exergy *** nozzle angleθnotably affects the distribution of hot and cold spots on the lip surface of the SAI ***θfrom 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K.

关键词： Swirl anti-icing heat transfer exergy efficiency hot and cold spot aircraft engine

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic Energy Estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng yuan Yuzhong Zhang Shiqiang Liu Rong zhu State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.18%to 14.71%)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

Finite-Time Stabilization for Constrained Discrete-time Systems by Using Model Predictive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1656-1666页

作者： Bing zhu Xiaozhuoer yuan Li Dai Zhiwen Qiang IEEE the Seventh Research Division Beihang UniversityBeijing 100191China the School of Automation Beijing Institute of TechnologyBeijing 100081China

In this paper, a model predictive control(MPC)framework is proposed for finite-time stabilization of linear and nonlinear discrete-time systems subject to state and control constraints. The proposed MPC framework guarantees the finite-time convergence property by assigning the control horizon equal to the dimension of the overall system, and only penalizing the terminal cost in the optimization, where the stage costs are not penalized explicitly. A terminal inequality constraint is added to guarantee the feasibility and stability of the closed-loop *** feasibility can be improved via augmentation. The finite-time convergence of the proposed MPC is proved theoretically,and is supported by simulation examples.

关键词： Constraints deadbeat control finite-time stabilization model predictive control(MPC)

Micro-flow structure at regime transition from bubbling to turbulent fluidization in a fluidized bed

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Particuology 2024年第6期89卷 117-130页

作者： Chaoyu Yan Yue yuan Xiaoyang Wei Jesse zhu State Key Laboratory of Heavy Oil Processing Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China China Beacons Institute The University of NottinghamNingbo315100China Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity *** fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the system performance in practical *** the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent ***,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet multiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent *** transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).The results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bottom *** wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency *** sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized *** micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale *** work provides a systematic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.

关键词： Flow regime transition Bubbling fluidization Turbulent fluidization Micro-flow structure Differential pressure fluctuation

Notch signaling pathway in cancer:from mechanistic insights to targeted therapies

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2527-2563页

作者： Qingmiao Shi Chen Xue Yifan zeng Xin yuan Qingfei Chu Shuwen Jiang Jinzhi Wang Yaqi Zhang Danhua zhu Lanjuan Li State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesNational Medical Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Notch signaling,renowned for its role in regulating cell fate,organ development,and tissue homeostasis across metazoans,is highly conserved throughout *** Notch receptor and its ligands are transmembrane proteins containing epidermal growth factor-like repeat sequences,typically necessitating receptor-ligand interaction to initiate classical Notch signaling *** evidence indicates that the Notch signaling pathway serves as both an oncogenic factor and a tumor suppressor in various cancer *** of this pathway promotes epithelial-mesenchymal transition and angiogenesis in malignancies,closely linked to cancer proliferation,invasion,and ***,the Notch signaling pathway contributes to maintaining stem-like properties in cancer cells,thereby enhancing cancer *** regulatory role of the Notch signaling pathway in cancer metabolic reprogramming and the tumor microenvironment suggests its pivotal involvement in balancing oncogenic and tumor suppressive ***,the Notch signaling pathway is implicated in conferring chemoresistance to tumor ***,a comprehensive understanding of these biological processes is crucial for developing innovative therapeutic strategies targeting Notch *** review focuses on the research progress of the Notch signaling pathway in cancers,providing in-depth insights into the potential mechanisms of Notch signaling regulation in the occurrence and progression of ***,the review summarizes pharmaceutical clinical trials targeting Notch signaling for cancer therapy,aiming to offer new insights into therapeutic strategies for human malignancies.

关键词： Notch invasion involvement

Numerical investigation of the photo-thermal characteristics of a direct absorption solar collector using Monte Carlo and finite volume methods

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Science China(Technological Sciences) 2024年第8期67卷 2436-2448页

作者： zhu YanLong LI SuNing FAN JianHua KONG WeiQiang yuan yuan TAN HePing School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Civil Engineering and Mechanical Engineering Technical University of DenmarkKoppels AlléBuilding 4042800 Kgs.LyngbyDenmark School of Vehicle and Energy Yanshan UniversityQinhuangdao 066004China

In this study, a novel model of photothermal conversion in a direct absorption solar collector based on the Monte Carlo and finite volume methods was built and validated and the temperatures of the novel and traditional solar collectors were compared. The sensitivity of the parameters to the radiative heat loss was investigated. Finally, the radiative heat transfer characteristics were discussed using the radiative exchange factor. The results of this study validated the advantages of the novel solar collector at both the surface and fluid temperatures. Under the conditions used in this study, the maximum temperature difference of the novel solar collector was 30 K, compared with 193 K for the traditional solar collector. Furthermore, the collector was divided into several units along the flow direction. The radiative exchange factor indicated that with an increase in the attenuation coefficient, the percentage of radiation intensity in the total solar radiation absorbed by the corresponding unit ***, it decreased with an increase in the incident angle and scattering albedo. These results provide a reference for addressing the low efficiency and thermal damage caused by traditional solar collectors at high temperatures.

关键词： direct absorption solar collector radiative heat transfer Monte Carlo

Polysaccharides of Aspergillus cristatus attenuate obesity by regulating gut microbiota and gut microbiota-related metabolites

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Food Science and Human Wellness 2024年第3期13卷 1513-1530页

作者： Mingzhi zhu Bohao Shang Fang Zhou Yong yuan Feiyan Yin Jin Cao Jianan Huang Kunbo Wang Xin zeng Maiquan Li Zhonghua Liu College of Horticulture Hunan Agricultural UniversityChangsha 410128China College of Life Sciences Huaibei Normal UniversityHuaibei 235000China Hunan Tea Group Co. Ltd.Changsha 410128China School of Food Science and Technology Hunan Agricultural UniversityChangsha 410128China

Golden-flower fungus,the only dominant microorganism determining the Fu-brick tea quality through fermentation and the important microbe in Liupao tea,is considered a potential probiotic fungus based on its anti-obesity ***,the classification of golden-flower fungi is still controversial;the anti-obesity effect of golden-flower fungus polysaccharides remains *** this study,we identify a golden-flower strain as Aspergillus cristatus based on morphological characteristics and multigene phylogeny analysis,which resolves the controversy of ***,we find *** polysaccharides(ACPS)attenuate obesity in *** modulate gut bacterial *** which Akkermansia,Akkermansia muciniphila,Bacteroides,Romboutsia,Blautia,and Desulfovibrio are considered the core microbes regulated by *** increase fecal total short-chain fatty acid content and serum,hepatic,and fecal total bile acid ***,ACPS-induced gut microbiota alteration plays a causal role in the protection from obesity,according to a fecal transplantation ***,ACPS ameliorate obesity by regulating gut microbiota and gut microbiota-related metabolites.

关键词： Golden-flower fungus Aspergillus cristatus Polysaccharides Obesity Gut microbiota

Growth process,defects,and dopants of bulkβ-Ga_(2)O_(3)semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： Yan-shen Wang Ming-zhi zhu yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-sizeβ-Ga_(2)O_(3)single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3)are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3)single crystals are summarized and compared in ***,the defects ofβ-Ga_(2)O_(3)single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3)are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3)single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

Quick Hosting Capacity Evaluation Based on Distributed Dispatching for Smart Distribution Network Planning with Distributed Generation

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 128-140页

作者： Bing Sun Ruipeng Jing Leijiao Ge yuan zeng Shimeng Dong Luyang Hou the School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China State Grid Corporation of China BeijingChina the School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijingChina

The smart distribution network(SDN)is integrat ing increasing distributed generation(DG)and energy storage(ES).Hosting capacity evaluation is important for SDN plan ning with *** and ES are usually invested by users or a third party,and they may form friendly microgrids(MGs)and operate *** centralized dispatching meth od no longer suits for hosting capacity evaluation of SDN.A quick hosting capacity evaluation method based on distributed optimal dispatching is ***,a multi-objective DG hosting capacity evaluation model is established,and the host ing capacity for DG is determined by the optimal DG planning *** steady-state security region method is applied to speed up the solving process of the DG hosting capacity evalua tion ***,the optimal dispatching models are estab lished for MG and SDN respectively to realize the operating *** the distributed dispatching strategy,the dual-side optimal operation of SDN-MGs can be realized by several iterations of power exchange ***,an SDN with four MGs is conducted considering multiple flexible *** shows that the DG hosting capacity of SDN oversteps the sum of the maximum active power demand and the rated branch ***,the annual DG electricity oversteps the maximum active power demand value.

关键词： Smart distribution network(SDN) microgrid hosting capacity multi-objective optimization distributed opti mal dispatching flexible resource