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Dynamically updated digital twin for prognostics and health management:Application in permanent magnet synchronous motor

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Chinese Journal of Aeronautics 2024年第6期37卷 244-261页

作者： Haoyu guo Shaoping WANG jian SHI Tengfei MA Giorgio GUGLIERI Rujun jia Fausto LIZZIO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Tianmushan Laboratory Hangzhou 310023China Department of Mechanical and Aerospace Engineering Polytechnic University of TurinTurin 10129Italy Beihang Ningbo Research Institute Ningbo 315800China

Current research on Digital Twin(DT)based Prognostics and Health Management(PHM)focuses on establishment of DT through integration of real-time data from various sources to facilitate comprehensive product monitoring and health ***,there still exist gaps in the seamless integration of DT and PHM,as well as in the development of DT multi-field coupling modeling and its dynamic update *** the product experiences long-period degradation under load spectrum,it is challenging to describe the dynamic evolution of the health status and degradation progression *** addition,DT update algorithms are difficult to be integrated simultaneously by current *** paper proposes an innovative dual loop DT based PHM framework,in which the first loop establishes the basic dynamic DT with multi-filed coupling,and the second loop implements the PHM and the abnormal detection to provide the interaction between the dual loops through updating *** proposed method pays attention to the internal state changes with degradation and interactive mapping with dynamic parameter ***,the Independence Principle for the abnormal detection is proposed to refine the theory of *** at the first loop focus on accurate modeling of multi-field coupling,while the events at the second loop focus on real-time occurrence of anomalies and the product degradation *** interaction and collaboration between different loop models are also ***,the Permanent Magnet Synchronous Motor(PMSM)is used to verify the proposed *** results show that the modeling method proposed can accurately track the lifecycle performance changes of the entity and carry out remaining life prediction and health management effectively.

关键词： Digital Twin(DT) Dynamic Update Independence Principle Multi-field Coupling Permanent Magnet Synchronous Motor(PMSM) Prognostics and Health Management(PHM)

Abdominal compartment syndrome in patients with severe acute pancreatitis in early stage

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World Journal of Gastroenterology 2008年第22期14卷 3541-3548页

作者： Hong Chen Fei Li jia-Bang Sun jian-guo jia Department of General Surgery Xuan Wu Hospital of Capital Medical University Beijing 100053 China

AIM: To study retrospectively the influence of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) in patients with early acute pancreatitis (AP) (during the first week after admission) on physiological functions, and the association of the presence of IAH/ACS and outcome. METHODS: Patients (n = 74) with AP recruited in this study were divided into two groups according to intra-abdominal pressure (IAP) determined by indirect measurement using the transvesical route via Foley bladder catheter during the first week after admission. Patients (n = 44) with IAP ≥ 12 mmHg were assigned in IAH group, and the remaining patients (n = 30) with IAP < 12 mmHg in normal IAP group. For analysis of the influence of IAH/ACS on organ function and outcome, the physiological parameters and the occurrence of organ dysfunction during intensive care unit (ICU) stay were recorded, as were the incidences of pancreatic infection and in-hospital mortality. RESULTS: IAH within the first week after admission was found in 44 patients (59.46%). Although the APACHE Ⅱ scores on admission and the Ranson scores within 48 h after hospitalization were elevated in IAH patients in early stage, they did not show the statistically significant differences from patients with normal IAP within a week after admission (16.18 ± 3.90 vs 15.70 ± 4.25, P = 0.616; 3.70 ± 0.93 vs 3.47 ± 0.94, P = 0.285, respectively). ACS in early AP was recorded in 20 patients (27.03%). During any 24-h period ofthe first week after admission, the recorded mean IAP correlated significantly with the Marshall score calculated at the same time interval in IAH group (r = 0.635, P < 0.001). Although ACS patients had obvious amelioration in physiological variables within 24 h after decompression, the incidences of pancreatitic infection, septic shock, multiple organ dysfunction syndrome (MODS) and death in the patients with ACS were significantly higher than that in other patients without ACS (pancreatitic infectio

关键词： Acute pancreatitis Abdominal compartment syndrome Intra-abdominal pressure Intra-abdominal hypertension Organ dysfunction

Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen Shu-lin Lü Di-jia Zhao Wei guo jian-yu Li Shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

Prevalence of musculoskeletal symptoms among industrial employees in a modern industrial region in Beijing,China

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Chinese Medical Journal 2019年第7期132卷 789-797页

作者： Ting Wang Ya-Li Zhao Li-Xiao Hao jian-guo jia Department of General Practice The School of General Practice and Continuing EducationCapital Medical UniversityBeijing 100069China Department of General Medicine Xuanwu Hospital of Capital Medical UniversityBeijing 100053China Department of General Surgery Xuanwu Hospital of Capital Medical UniversityBeijing 100053China

Background:Growing industrialization of China exposes its labor population to the risk of musculoskeletal disorders(MSDs).This study aimed to investigate the prevalence and risk factors of MSDs in a modern industrial region of ***:A cross-sectional study included 1415 employees in six industrial companies was conducted between January 2018 and May 2018 in Fangshan district,Beijng,*** Musculoskeletal Questionnaire(NMQ)was used to collect the information about *** factors,lifestyle factors,health and medical factors,and work-related factors were collected as independent *** statistics,the chi-squared(/2)test,and binary logistic regression analysis were used to analyze ***:Among 1415 participants,498 reported *** regions involved were the neck(25.16%),shoulders(17.17%),and upper back(13.29%).There was a significant statistical difference between frontline industrial workers and other staff in the prevalence of self-reported symptoms involving the shoulders(Х^2=4.33,P=0.037),wrists and hands(Х^2=8.90,P=0.003),and ankles and feet(Х^2=12.88,P<0.001).Increased age(P=0.005,OR=1.63;P=0.001,OR=2.33),a high or a low salary(P<0.001,OR=0.49;P<0.001,OR=0.30),night-shift(P=0.027,OR=1.46),two-week-history of illness and treatment(P=0.004,OR=5.60;P=0.013,OR=4.19),concurrent chronic diseases(P=0.001,OR=3.45;P=0.092,OR=7.81),limited access to health information(P=0.004,OR=0.49),and negative attitude towards seeking healthcare(P=0.010,OR=1.77;P=0.009,OR=2.75)were associated with MSDs in frontline *** gender(P<0.001,OR=2.30),high education(P=0.001,OR=1.96),no exercises(P=0.027,OR=0.59),night-shift(P=0.017,OR=1.98),concurrent chronic diseases(P=0.002,OR=3.73;P=0.020,OR=13.42),limited access to health information(P=0.013,OR=0.53),far distance to medical institution(P=0.009,OR=1.83),and negative propensity(P=0.009,OR=1.94;P=0.014,OR=2.74)were associated with MSDs in other ***:The prevalence of MSDs

关键词： Cross-sectional study Musculoskeletal disorders Occupational injuries Epidemiology

The function of doping nitrogen on removing fluoride with decomposing La-MOF-NH_2:Density functional theory calculation and experiments

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Journal of Environmental Sciences 2024年第1期135卷 118-129页

作者： Hongguo Zhang KuilinWan jia Yan Qian Li Yufang guo Lei Huang Samuel Raj Babu Arulmani jian Luo School of Environmental Science and Engineering Guangzhou UniversityGuangzhou 510006China Guangzhou University-Linkoping University Research Center on Urban Sustainable Development Guangzhou UniversityGuangzhou 510006China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Fluoride is an important pollutant in wastewater,and adsorption is an effective way to remove *** nitrogen plays an important role in adsorbent materials,computational models were developed to understand the changes in work function resulting from nitrogen ***-N-C-800℃,was prepared by pyrolyzing La-MOF-NH_(2)to verify the influence on the performance of removing fluoride by *** and electrochemical performance tests were performed to characterize La-N-C-800℃.Adsorption kinetics,adsorption thermodynamics,initial concentrations,pH,and ions competition were investigated using La-N-C-800℃for fluoride *** addition,density functional theory was applied to evaluate the function of *** nitrogen atoms were added,the density of states,partial density of states,populations,and different orbits of charge were calculated to discover deep *** strengthened the carbon structure and La_(2)O_(3)structure to remove *** addition,nitrogen can also act as an adsorption site in the carbon *** results provide design ideas for improving the performance of adsorbent materials by doping elements.

关键词： Capacitive deionization Fluoride La-MOFs Doping nitrogen

Harnessing data using symbolic regression methods for discovering novel paradigms in physics

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 1-11页

作者： jianyang guo Wan-jian Yin College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Shanghai Qi Zhi Institute Shanghai 200232China Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006China

In recent years,machine-learning methods have profoundly impacted research in the interdisciplinary fields of ***,most machine-learning models lack interpretability,and physicists doubt the credibility of their conclusions because they cannot be combined with prior physical ***,this review focuses on symbolic regression,which is an interpretable machine-learning ***,the relevant concepts of machine learning are introduced in conjunction with ***,we provide an overview of symbolic regression ***,the recent directions for the application of symbolic regression methods in different subfields of physics are outlined,and an overview of the ways in which the applications of symbolic regression have evolved in the realm of physics is *** major aim of this review is to introduce the basic principles of symbolic regression and explain its applications in the field of physics.

关键词： machine learning genetic programming symbolic regression

Vertically aligned montmorillonite aerogel-encapsulated polyethylene glycol with directional heat transfer paths for efficient solar thermal energy harvesting and storage

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 907-916页

作者： Qijing guo Cong guo Hao Yi Feifei jia Shaoxian Song Key Laboratory of Green Utilization of Critical Non-metallic Mineral Resources Ministry of EducationWuhan University of TechnologyWuhan 430070China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyWuhan 430070China

The conversion and storage of photothermal energy using phase change materials(PCMs)represent an optimal approach for harnessing clean and sustainable solar ***,we encapsulated polyethylene glycol(PEG)in montmorillonite aerogels(3D-Mt)through vacuum impregnation to prepare 3D-Mt/PEG composite *** used as a support matrix,3D-Mt can effectively prevent PEG leakage and act as a flame-retardant barrier to reduce the flammability of ***,3D-Mt/PEG demonstrates outstanding shape retention,increased thermal energy storage density,and commendable thermal and chemical *** phase transition enthalpy of 3D-Mt/PEG can reach 167.53 J/g and remains stable even after 50 heating-cooling ***,the vertical sheet-like structure of 3D-Mt establishes directional heat transport channels,facilitating efficient phonon *** configuration results in highly anisotropic thermal conductivities that ensure swift thermal responses and efficient heat *** study addresses the shortcomings of PCMs,including the issues of leakage and inadequate flame *** achieves the development and design of 3D-Mt/PEG with ultrahigh strength,superior flame retardancy,and directional heat ***,this work offers a design strategy for the preparation of high-performance composite *** 3D-Mt/PEG with vertically aligned and well-ordered array structure developed in this research shows great potential for thermal management and photothermal conversion applications.

关键词： montmorillonite aerogel polyethylene glycol phase change materials solar thermal energy storage flame retardant

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Effects of traditional Chinese medicine on intestinal mucosal permeability in early phase of severe acute pancreatitis

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Chinese Medical Journal 2010年第12期123卷 1537-1542页

作者： CHEN Hong LI Fei jia jian-guo DIAO Yong-peng LI Zong-xin SUN jia-bang Department of General Surgery Xuan Wu Hospital of Capital Medical University Beijing 100053 China Department of Traditional Chinese Medicine Xuan Wu Hospital of Capital Medical University Beijing 100053 China

Background Traditional Chinese medicine has been used widely for many years in China to treat acute pancreatitis. We have investigated the effects of Dachengqi decoction on intestinal mucosal permeability and outcome in patients with severe acute pancreatitis （SAP）. Methods Forty patients with sustained SAP that required admission to the surgical intensive care unit were enrolled prospectively in the study. All of these patients were divided randomly into the Dachengqi decoction group （n=-20） and control group （n=-20） on admission. Intestinal permeability was assessed by measuring absorption of two metabolically inert markers, lactulose （L） and mannitol （M）, which were administered orally. Serum concentrations of endotoxin （lipopolysaccharide, LPS） and the ratio of lactulose to mannitol in urine （L/M） were detected in all patients. Results Compared with those in the control group, urinary L/M ratio decreased significantly in the Dachengqi decoction group on the 7th day after admission （P=0.001）. Also, serum concentrations of LPS were reduced on the 5th and 7th day after admission （P=-0.006, P=0.008, respectively）. Incidence of multiple organ dysfunction syndrome （MODS） and pancreatic infection was significantly lower in the Dachengqi decoction group compared with those in the control group （P=-0.038, P=-0.025, respectively）. Conclusion Dachengqi decoction may promote the recovery of intestinal mucosal permeability and decrease the incidence of MODS and pancreatic infection in patients with SAP.

关键词： medicine, Chinese traditional Dachengqi decoction pancreatitis, acute necrotizing bacterial translocation