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Sectional model test study on vortex-excited resonance of vehicle-bridge system of Shanghai Bridge over

Li ZHOU, Yaojun GE

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 67-72 doi: 10.1007/s11709-009-0007-4

摘要： It is necessary to study how vehicles influence the vortex-excited resonance of vehicle-bridge systems, because lock-in wind speed is low and vortex-excited resonance is sensitive to any change in the main girder sections. Based on the Shanghai Bridge over the Yangtse River, the vortex-excited resonance of a 1∶60 scale sectional model was tested in a TJ-1wind tunnel, with or without vehicles at the attack angle of 0°, +3 and -3°, respectively. The conversion relationships between the resonant amplitudes of the sectional model and that of the prototype bridge were also established by mode shape correction. The result indicates that: 1) for the bridge with vehicles, the vertical vortex-excited resonance is accompanied by torsion vibration with the same frequency, and vice versa, 2) the amplitude of vortex-excited resonance of the bridge with vehicles is much larger than that of the bridge without vehicles, and 3) the lock-in wind speed of the vortex-excited resonance becomes smaller due to the disturbance of vehicles. It is obvious that vehicles bring about changes in the aerodynamic shape of the main girder. Therefore, the influence of vehicles on vortex-excited resonance performance of vehicle-bridge systems, in terms of both amplitude and mode, should not be ignored.

关键词： vehicle-bridge system     sectional mode     vortex-excited resonance     wind tunnel test     mode shape correction    

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and determinations of physical inactivity among public hospital employees in Shanghai, China: a cross-sectional

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《医学前沿（英文）》 2015年 第9卷 第1期   页码 100-107 doi: 10.1007/s11684-014-0372-9

摘要：

This study aims to explore the prevalence and determinations of physical inactivity among hospital employees in Shanghai, China. A cross-sectional study of 4612 employees aged 19 to 68 years was conducted through stratified cluster sampling from different classes of Shanghai hospitals in 2011. The total physical activity was evaluated using the metabolic equivalent according to the Global Physical Activity Questionnaire. Among the participants, 38.5%, 32.3%, and 64.6% of the employees are inactive at work, commuting, and taking leisure time, respectively. Up to 41.8% of the men and 37.8% of the women (P = 0.012) are physically inactive. When the age and educational level are adjusted, male doctors and medical technicians show a higher percentage of physical inactivity than male workers in logistics (P = 0.001). Among females, employees who are working in second- and third-class hospitals show a higher proportion of physical inactivity than those who are working in community health care centers. Logistic regression analyses show that the odds ratios (ORs) of leisure-time physical inactivity associated with the intensity of physical activity at work are 2.259, 2.897, and 4.266 for men (P<0.001) and 2.456, 3.259, and 3.587 for women (P<0.001), respectively. The time during commuting activities is significantly associated with leisure-time physical inactivity in either sex (OR= 2.116 for men and 2.173 for women, P<0.001). Hospital employees, particularly doctors and medical technicians, show a higher proportion of physical inactivity than other inhabitants in Shanghai. The time and intensity of activity at work and commuting are associated with leisure-time activities.

关键词： prevalence     determination     employee     public hospital     cross-sectional study     physical inactivity    

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Cross-sectional network analysis of plasma proteins/metabolites correlated with pathogenesis and therapeutic

《医学前沿（英文）》 doi: 10.1007/s11684-023-1022-x

摘要： The treatment of PML/RARA+ acute promyelocytic leukemia (APL) with all-trans-retinoic acid and arsenic trioxide (ATRA/ATO) has been recognized as a model for translational medicine research. Though an altered microenvironment is a general cancer hallmark, how APL blasts shape their plasma composition is poorly understood. Here, we reported a cross-sectional correlation network to interpret multilayered datasets on clinical parameters, proteomes, and metabolomes of paired plasma samples from patients with APL before or after ATRA/ATO induction therapy. Our study revealed the two prominent features of the APL plasma, suggesting a possible involvement of APL blasts in modulating plasma composition. One was characterized by altered secretory protein and metabolite profiles correlating with heightened proliferation and energy consumption in APL blasts, and the other featured APL plasma-enriched proteins or enzymes catalyzing plasma-altered metabolites that were potential trans-regulatory targets of PML/RARA. Furthermore, results indicated heightened interferon-gamma signaling characterizing a tumor-suppressing function of the immune system at the first hematological complete remission stage, which likely resulted from therapy-induced cell death or senescence and ensuing supraphysiological levels of intracellular proteins. Overall, our work sheds new light on the pathophysiology and treatment of APL and provides an information-rich reference data cohort for the exploratory and translational study of leukemia microenvironment.

关键词： acute promyelocytic leukemia     plasma proteomics     plasma metabolomics     cross-sectional correlation network     pathogenesis     treatment    

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Cross-sectional prevalence and pattern of non-anaemia severe malaria among 2–10 year olds in Sokoto in

《医学前沿（英文）》 2022年 第16卷 第6期   页码 969-974 doi: 10.1007/s11684-021-0912-z

摘要： Malaria is highly prevalent in Nigeria and accounts for approximately 40% of global malaria mortality. However, most reports on severe malaria in Nigeria are from hospital-based studies without accurate information from communities; thus, malaria-related deaths in the community are left untracked. This study aimed to describe the prevalence and pattern of severe malaria in a community in Northwestern Nigeria. A cross-sectional study was conducted among 2–10-year-old children in Sokoto, in August and December 2016, to determine the endemicity of malaria based on Plasmodium falciparum prevalence rate (PfPR2-10) and to describe the disease pattern. Severe malaria was diagnosed according to the World Health Organisation criteria. Data were described using Stata version 15. The prevalence of non-anaemia severe malaria was higher than expected (2.6%), considering the endemicity pattern which was mesoendemic based on a PfPR2-10 of 34.8%. The mean age of children with severe malaria was 3.73 years, and the male–female ratio was 2:1. However, 54.0% of the patients had hyperparasitaemia. A relatively high prevalence of non-anaemia severe malaria was found in Wamakko. This finding suggests the need to identify and treat cases in the community using modifications of current strategies, particularly seasonal malaria chemoprophylaxis.

关键词： severe malaria     nigeria     malaria mortality     PfPR2-10     intermediate malaria transmission    

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prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional

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《医学前沿（英文）》 2012年 第6卷 第3期   页码 322-328 doi: 10.1007/s11684-012-0204-8

摘要：

The aim of this study was to determine the prevalence of overweight and obese subjects in the Shanghai population of China and its association with undiagnosed hypertension, by taking age, gender and place of residence (urban or suburban) into account. A cross-sectional population-based survey was conducted in 2007. The sample included 13 359 participants aged 15–69 years. Weight, height, and blood pressure were recorded, and information about gender, age and place of residence was obtained. Overweight and obesity prevalence were calculated by the body mass index (BMI) definition recommended by Working Group on Obesity in China (normal weight, 18.5–23.9 kg/m2; overweight, 24–27.9 kg/m2; obesity,≥28 kg/m2). Undiagnosed hypertension was defined by China criteria in accord with that of WHO-ISH (subjects with systolic pressure≥140 mmHg, and/or diastolic pressure≥90 mmHg). Multiple logistic regression analyses were used to assess the association of overweight or obesity with undiagnosed hypertension by adjusting for age, gender and place of residence. The overall overweight, obesity, and undiagnosed hypertension prevalence were 27.6% (95% CI: 26.8–28.4), 6.6% (95% CI: 6.2–7.0), and 15.5% (95% CI: 14.9–16.1), respectively. Compared to normal weight subjects, the odds ratios (OR) for subjects who were overweight and had hypertension was 2.33 (95% CI: 2.10–2.59); that for obesity and hypertension was 4.27 (95% CI: 3.66–4.99). These data suggest that overweight and obesity prevalence and their association with undiagnosed hypertension are high in our study population.

关键词： overweight     obesity     undiagnosed hypertension     prevalence     association    

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terminating the Bacillus Calmette--Guérin booster vaccination: subgroup analysis of a population-based cross-sectional

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 528-535 doi: 10.1007/s11684-017-0573-0

摘要：

The prevalence of tuberculosis infection among adolescents born after terminating the Bacillus Calmette–Guérin (BCG) booster vaccination in China was estimated using tuberculin skin testing (TST) and QuantiFERON-TB Gold assay (QFT) to investigate the influence of neonatal BCG vaccination on the performance of TST. Data analysis was conducted for 2831 eligible participants aged 5–15 years from the baseline survey of a population-based multi-center prospective study. The prevalence rates of TST (induration≥10 mm) and QFT positivity were 9.3% (264/2827) and 2.5% (71/2831), respectively. The rate of QFT indeterminate result was 2.2% (62/2831). The overall agreement between TST and QFT was low (concordance= 88.0%; κ coefficient= 0.125). Only TST was positively associated with BCG vaccination with an adjusted odds ratio of 1.71 [95% confidence interval, 1.26–2.31]. A history of close contact with patients of active TB was significantly associated with positivity for TST and QFT. Our results suggested that BCG neonatal vaccination still affects TST performance, and a two-step approach might be considered for TB infection testing among adolescents in China.

关键词： tuberculin skin test     interferon-γ release assays     adolescent     agreement    

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serum miR-154-5p and urinary albumin excretion rates in patients with type 2 diabetes mellitus: a cross-sectional

Huiwen Ren, Can Wu, Ying Shao, Shuang Liu, Yang Zhou, Qiuyue Wang

《医学前沿（英文）》 2020年 第14卷 第5期   页码 642-650 doi: 10.1007/s11684-019-0719-3

摘要： This study aimed to investigate the correlation between serum miR-154-5p and urinary albumin to creatinine ratio (UACR) in patients with type 2 diabetes mellitus (T2DM) and the association with biomarkers of inflammation and fibrosis in diabetic kidney disease (DKD). A total of 390 patients with T2DM were divided into three groups: normal albuminuria (UACR<30 mg/g, =136, NA), microalbuminuria (UACR at 30–300 mg/g, =132, MA), and clinical albuminuria (UACR>300 mg/g, =122, CA). Circulating miR-154-5p, inflammatory (C-reactive protein (CRP); erythrocyte sedimentation rate (ESR); and tumor necrosis factor-α (TNF-α) and fibrotic markers (vascular endothelial growth factor (VEGF); transforming growth factor-β1 (TGF-β1); and fibronectin (FN)), and other biochemical indicators were assessed via real-time PCR, enzyme-linked immunosorbent assay, and chemiluminescence assay in patients with T2DM and 138 control subjects (NC). UACR, miR-154-5p, glycated hemoglobin (HbA1c), serum creatinine (sCr), blood urea nitrogen (BUN), ESR, CRP, VEGF, TNF-α, TGF-β1, and FN were significantly higher and the estimated glomerular filtration rate (eGFR) was significantly lower in NA, MA, and CA groups than in NC subjects ( <0.05). Elevated levels of UACR and miR-154-5p were directly correlated with HbA1c, sCr, BUN, ESR, CRP, VEGF, TNF-α, TGF-β1, and FN and negatively correlated with eGFR ( <0.05). miR-154-5p, HbA1c, sCr, BUN, eGFR, ESR, CRP, VEGF, TNF-α, TGF-β1, and FN were important factors affecting UACR. These findings indicated that elevated serum miR-154-5p is significantly correlated with high UACR in patients with T2DM and may offer a novel reference for the early diagnosis of DKD.

关键词： type 2 diabetes mellitus     diabetic kidney disease     miR-154-5p     urinary albumin to creatinine ratio    

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Seroprevalence of influenza viruses in Shandong, Northern China during the COVID-19 pandemic

《医学前沿（英文）》 2022年 第16卷 第6期   页码 984-990 doi: 10.1007/s11684-022-0930-5

摘要： Nonpharmaceutical interventions (NPIs) have been commonly deployed to prevent and control the spread of the coronavirus disease 2019 (COVID-19), resulting in a worldwide decline in influenza prevalence. However, the influenza risk in China warrants cautious assessment. We conducted a cross-sectional, sero-epidemiological study in Shandong Province, Northern China in mid-2021. Hemagglutination inhibition was performed to test antibodies against four influenza vaccine strains. A combination of descriptive and meta-analyses was adopted to compare the seroprevalence of influenza antibodies before and during the COVID-19 pandemic. The overall seroprevalence values against A/H1N1pdm09, A/H3N2, B/Victoria, and B/Yamagata were 17.8% (95% CI 16.2%–19.5%), 23.5% (95% CI 21.7%–25.4%), 7.6% (95% CI 6.6%–8.7%), and 15.0 (95% CI 13.5%–16.5%), respectively, in the study period. The overall vaccination rate was extremely low (2.6%). Our results revealed that antibody titers in vaccinated participants were significantly higher than those in unvaccinated individuals (P < 0.001). Notably, the meta-analysis showed that antibodies against A/H1N1pdm09 and A/H3N2 were significantly low in adults after the COVID-19 pandemic ( P < 0.01). Increasing vaccination rates and maintaining NPIs are recommended to prevent an elevated influenza risk in China.

关键词： influenza virus     seroprevalence     antibody     COVID-19     cross-sectional study    

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Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode

Abdelkarim AMMAR,Amor BOUREK,Abdelhamid BENAKCHA

《能源前沿（英文）》 2020年 第14卷 第4期   页码 836-849 doi: 10.1007/s11708-017-0444-z

摘要： This paper proposes a design of control and estimation strategy for induction motor based on the variable structure approach. It describes a coupling of sliding mode direct torque control (DTC) with sliding mode flux and speed observer. This algorithm uses direct torque control basics and the sliding mode approach. A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC drawbacks and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple level. The sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation (SVM) inverter. The second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation, and consequently, increase the reliability of the system and decrease the cost of using sensors. The effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.

关键词： induction motor     direct torque control (DTC)     space vector modulation (SVM)     sliding mode control (SMC)     sliding mode observer (SMO)     dS1104    

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基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

《中国工程科学》 2004年 第6卷 第7期   页码 70-74

摘要：

由于CBC－MAC模式不可并行处理，提出了一种基于双重分组的并行认证模式(PKCB)。PKCB模式同并行认证模式PMAC相比，安全性和速率都有显著提高，PKCB认证模式与CTR（计数器）加密模式结合可构成分组密码算法的一种全工作模式。在此基础上提出了一种基于密钥计数的并行认证模式（KCTR－MAC）。KCTR－MAC模式安全性比PMAC模式高得多，而速率未降低，KCTR－MAC认证模式和CTR加密模式结合也可构成分组密码算法的一种全工作模式（2CTR），2CTR模式的综合性能不亚于标准模式CCM（CTR with CBC－MAC），是一种安全快速的实用模式。

关键词： 认证模式     CBC－MAC模式     PMAC模式     CTR模式     CCM模式    

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Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode

《结构与土木工程前沿（英文）》   页码 179-190 doi: 10.1007/s11709-022-0888-z

摘要： In this study, the mechanical properties of the composite plate were considered Gaussian random fields and their effects on the buckling load and corresponding mode shapes were studied by developing a semi-analytical non-intrusive approach. The random fields were decomposed by the Karhunen−Loève method. The strains were defined based on the assumptions of the first-order and higher-order shear-deformation theories. Stochastic equations of motion were extracted using Euler–Lagrange equations. The probabilistic response space was obtained by employing the non-intrusive polynomial chaos method. Finally, the effect of spatially varying stochastic properties on the critical load of the plate and the irregularity of buckling mode shapes and their sequences were studied for the first time. Our findings showed that different shear deformation plate theories could significantly influence the reliability of thicker plates under compressive loading. It is suggested that a linear relationship exists between the mechanical properties’ variation coefficient and critical loads’ variation coefficient. Also, in modeling the plate properties as random fields, a significant stochastic irregularity is obtained in buckling mode shapes, which is crucial in practical applications.

关键词： uncertain composite plate     stochastic assume mode method     Karhunen−Loève theorem     polynomial chaos approach     plate buckling     irregularity in buckling mode shapes    

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Experimental investigation of evolutive mode-I and mode-II fracture behavior of fiber-reinforced cemented

《结构与土木工程前沿（英文）》 2023年 第17卷 第2期   页码 256-270 doi: 10.1007/s11709-022-0924-z

摘要： The curing temperature-dependent cement hydration causes the nonlinear evolution of fracture behavior and properties of fiber-reinforced cemented paste backfill (CPB) and thus influences the stability of mine backfill materials in deep mines. Therefore, the coupled effect of curing temperature (20, 35, and 45 °C) and cement hydration at different curing times (3, 7, and 28 d) on the mode-I and mode-II fracture behavior and properties of fiber-reinforced CPB is investigated. A comprehensive experimental testing program consisting of semicircular bend tests, direct shear tests, measurement of volumetric water content and matric suction, TG/DTG tests, and SEM observation is carried out. The results show that the coupled thermochemical effect results in strongly nonlinear development of pre- and post-peak behavior of fiber-reinforced CPB. Moreover, the results discover a positive linear correlation between fracture toughness and shear strength parameters and also reveal the vital role played by matric suction in the formation of fracture toughness. Furthermore, predictive functions are developed to estimate the coupled thermochemical effect on the development of KIc and KIIc. Therefore, the findings and the developed mathematical tools have the potential to promote the successful application of fiber-reinforced CPB technology in deep underground mines.

关键词： fiber reinforcement     cemented paste backfill     fracture behavior     underground mine     cement hydration    

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An adaptive sliding mode control technology for weld seam tracking

Jie LIU,Youmin HU,Bo WU,Kaibo ZHOU,Mingfeng GE

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 95-101 doi: 10.1007/s11465-015-0332-3

摘要：

A novel adaptive sliding mode control algorithm is derived to deal with seam tracking control problem of welding robotic manipulator, during the process of large-scale structure component welding. The proposed algorithm does not require the precise dynamic model, and is more practical. Its robustness is verified by the Lyapunov stability theory. The analytical results show that the proposed algorithm enables better high-precision tracking performance with chattering-free than traditional sliding mode control algorithm under various disturbances.

关键词： weld seam tracking     welding robotic manipulator     adaptive control     sliding mode control    

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Relative vibration identification of cutter and workpiece based on improved bidimensional empirical mode

Jiasheng LI, Xingzhan LI, Wei WEI, Pinkuan LIU

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 227-239 doi: 10.1007/s11465-020-0587-1

摘要： In the process of cutting, the relative vibration between the cutter and the workpiece has an important effect on the surface topography. In this study, the bidimensional empirical mode decomposition (BEMD) method is used to identify such effect. According to Riesz transform theory, a type of isotropic monogenic signal is proposed. The boundary data is extended on the basis of a similarity principle that deals with serious boundary effect problem. The decomposition examples show that the improved BEMD can effectively solve the problem of boundary effect and decompose the original machined surface topography at multiple scales. The characteristic surface topography representing the relative vibration between the cutter and the workpiece through feature identification is selected. In addition, the spatial spectrum analysis of the extracted profile is carried out. The decimal part of the frequency ratio that has an important effect on the shape of the contour can be accurately identified through contour extraction and spatial spectrum analysis. The decomposition results of simulation and experimental surface morphology demonstrate the validity of the improved BEMD algorithm in realizing the relative vibration identification between the cutter and the workpiece.

关键词： bidimensional empirical mode decomposition     spatial spectrum analysis     boundary effect     vibration identification     surface topography    

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Exploration of interconnected factory mode: Haier Jiaozhou Air Conditioner Interconnected Factory

Yunjie ZHOU

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 500-503 doi: 10.15302/J-FEM-2017105

关键词： interconnected factory mode     user-centered     mass customization     interconnection    

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标题 作者 时间 类型 操作

Sectional model test study on vortex-excited resonance of vehicle-bridge system of Shanghai Bridge over

Li ZHOU, Yaojun GE

期刊论文

and determinations of physical inactivity among public hospital employees in Shanghai, China: a cross-sectional

null

期刊论文

Cross-sectional network analysis of plasma proteins/metabolites correlated with pathogenesis and therapeutic

期刊论文

Cross-sectional prevalence and pattern of non-anaemia severe malaria among 2–10 year olds in Sokoto in

期刊论文

prevalence and its association with undiagnosed hypertension in Shanghai population, China: a cross-sectional

null

期刊论文

terminating the Bacillus Calmette--Guérin booster vaccination: subgroup analysis of a population-based cross-sectional

null

期刊论文

serum miR-154-5p and urinary albumin excretion rates in patients with type 2 diabetes mellitus: a cross-sectional

Huiwen Ren, Can Wu, Ying Shao, Shuang Liu, Yang Zhou, Qiuyue Wang

期刊论文

Seroprevalence of influenza viruses in Shandong, Northern China during the COVID-19 pandemic

期刊论文

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode

Abdelkarim AMMAR,Amor BOUREK,Abdelhamid BENAKCHA

期刊论文

基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

期刊论文

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode

期刊论文

Experimental investigation of evolutive mode-I and mode-II fracture behavior of fiber-reinforced cemented

期刊论文

An adaptive sliding mode control technology for weld seam tracking

Jie LIU,Youmin HU,Bo WU,Kaibo ZHOU,Mingfeng GE

期刊论文

Relative vibration identification of cutter and workpiece based on improved bidimensional empirical mode

Jiasheng LI, Xingzhan LI, Wei WEI, Pinkuan LIU

期刊论文

Exploration of interconnected factory mode: Haier Jiaozhou Air Conditioner Interconnected Factory

Yunjie ZHOU

期刊论文