Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (140)
  • Open Access

    ARTICLE

    Influencing Factors of Load Carrying Capacity and Cooperative Work Laws of Metro Uplift Piles

    Bo Liu1,*, Haoran Li1, Shuya Liu2

    Structural Durability & Health Monitoring, Vol.14, No.3, pp. 249-264, 2020, DOI:10.32604/sdhm.2020.06482 - 14 September 2020

    Abstract The buoyancy of groundwater can reduce the foundation bearing capacity and cause the metro tunnels to float as a whole, which threatens the safety of structures seriously. Therefore, uplift piles are set up to improve the structural stability. In this paper, FLAC3D software is used to establish the calculation models of pile foundation. The bearing failure process of uplift piles was simulated to study the influencing factors on single pile load bearing capacity as well as the cooperative work laws of pile groups. The load-displacement curves of pile top under different length-diameter ratios, pile-soil interface… More >

  • Open Access

    ARTICLE

    Mechanical Behavior of Light Trusses Made of Poplar Laminated Veneer Lumber and Connected with Bolts and Tooth Plates

    Yan Liu1, Yanfei Guo1, Xufeng Sun1,*, Meng Gong2

    Journal of Renewable Materials, Vol.8, No.9, pp. 1111-1127, 2020, DOI:10.32604/jrm.2020.09575 - 03 August 2020

    Abstract Poplar Laminated Veneer Lumber (Poplar LVL) is a new type of engineering materials with high strength, good reliability and small variability. Poplar LVL is manufactured from the fast-growing poplar, which is widely used in packaging, furniture and others, however, is rarely adopted in construction. In order to explore the feasibility of poplar LVL trusses in construction of roof, four 4.5-m-span Fink-and-Howe trusses were designed and assembled, which were made of poplar LVL with bolted- and tooth-plated connections. Vertical static loading on the upper chord joints of a truss was imposed by self-balancing test device. The… More >

  • Open Access

    ARTICLE

    A Genetic Algorithm to Solve Capacity Assignment Problem in a Flow Network

    Ahmed Y. Hamed1, Monagi H. Alkinani2, M. R. Hassan3, *

    CMC-Computers, Materials & Continua, Vol.64, No.3, pp. 1579-1586, 2020, DOI:10.32604/cmc.2020.010881 - 30 June 2020

    Abstract Computer networks and power transmission networks are treated as capacitated flow networks. A capacitated flow network may partially fail due to maintenance. Therefore, the capacity of each edge should be optimally assigned to face critical situations—i.e., to keep the network functioning normally in the case of failure at one or more edges. The robust design problem (RDP) in a capacitated flow network is to search for the minimum capacity assignment of each edge such that the network still survived even under the edge’s failure. The RDP is known as NP-hard. Thus, capacity assignment problem subject More >

  • Open Access

    ARTICLE

    Differential Effects of Ammonium and Nitrate on Growth Performance of Glechoma longituba under Heterogeneous Cd Stress

    Yanwei Feng1, Wen Lei2, Rui Gu3, Ping Zhao4, Shijun Ni1,*, Ningfei Lei3,*

    Phyton-International Journal of Experimental Botany, Vol.89, No.3, pp. 667-679, 2020, DOI:10.32604/phyton.2020.010160 - 22 June 2020

    Abstract Water, minerals, nutrients, etc., can be shared by physiological integration among inter-connected ramets of clonal plants. Nitrogen plays an important role in alleviating cadmium (Cd) stress for clonal plants. But how different forms of nitrogen affect growth performance of clonal plants subjected to heterogeneous Cd stress still remains poorly understood. A pot experiment was conducted to investigate the differential effects of ammonium and nitrate on growth performance of Glechoma longituba under heterogeneous Cd stress. In the experiment, parent ramets of Glechoma longituba clonal fragments were respectively supplied with modified Hoagland solution containing 7.5 mM ammonium, 7.5… More >

  • Open Access

    Experimental Analysis of the Performances of Unit Refrigeration Systems Based on Parallel Compressors with Consideration of the Volumetric and Isentropic Efficiency

    Daoming Shen1,2,*, Chao Gui1, Jinhong Xia1, Songtao Xue2,3

    FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 489-500, 2020, DOI:10.32604/fdmp.2020.08969 - 25 May 2020

    Abstract The performances of a refrigeration unit relying on compressors working in parallel have been investigated considering the influence of the compressor volumetric efficiency and isentropic efficiency on the compression ratio. Moreover, the following influential factors have been taken into account: evaporation temperature, condensation temperature and compressor suction-exhaust pressure ratio for different opening conditions of the compressor. The following quantities have been selected as the unit performance measurement indicators: refrigeration capacity, energy efficiency ratio (COP), compressor power consumption, and refrigerant flow rate. The experimental results indicate that the system refrigeration capacity and COP decrease with a More >

  • Open Access

    ARTICLE

    Research on the Measurement and Countermeasure of Coal Overcapacity in China: Based on Panel Data of 25 Provinces in China

    Rijia Ding1, Xingyao Zhou1,*, Rui Zhang1, Wanqiu Lu2

    Energy Engineering, Vol.117, No.1, pp. 27-39, 2020, DOI:10.32604/EE.2020.010372 - 28 February 2020

    Abstract Coal is the main energy source in China. At present, the coal overcapacity is still serious in China. Accurately measuring the degree of China’s coal overcapacity can scientifically resolve the overcapacity, and is the premise of guiding the healthy development of coal industry and energy system. Using the translog cost function and the panel data of coal industry in all provinces of China from 2002 to 2011 and from 2012 to 2016, the research measures and compares the coal production capacity of “golden decade” and “cold winter” in China. The results show that: (1) The More >

  • Open Access

    ARTICLE

    Right ventricular and pulmonary vascular function indices for risk stratification of patients with pulmonary regurgitation

    Alexander C. Egbe, William R. Miranda, Patricia A. Pellikka, Sorin V. Pislaru, Barry A. Borlaug, Srikanth Kothapalli, Sindhura Ananthaneni, Harigopal Sandhyavenu, Maria Najam, Mohamed Farouk Abdelsamid, Heidi M. Connolly

    Congenital Heart Disease, Vol.14, No.4, pp. 657-664, 2019, DOI:10.1111/chd.12768

    Abstract Background: We hypothesized that echocardiographic indices of right ventricular to pulmonary artery (RV‐PA) coupling were comparable to cardiac magnetic resonance imaging (CMRI)‐derived RV volumetric indices in predicting disease severity in chronic pulmonary regurgitation (PR).
    Methods: Patients with ≥ moderate PR (2003‐2015) with and without prior CMRI scans were enrolled into the study cohort and validation cohort, respectively. Endpoint was to determine the association between noninvasive RV‐PA coupling in‐ dices (tricuspid annular plane systolic excursion/right ventricular systolic pressure [TAPSE/RVSP] and fractional area change [FAC]/RVSP ratio) and markers of disease severity, and compared this association to that of CMRI‐derived… More >

  • Open Access

    ARTICLE

    Small unrepaired atrial septal defects display impaired exercise capacity compared with healthy peers

    Sebastian Udholm, Christian Rex, Filip Eckerström, Mine Onat, Camilla Nyboe, Vibeke E. Hjortdal

    Congenital Heart Disease, Vol.14, No.3, pp. 372-379, 2019, DOI:10.1111/chd.12740

    Abstract Objective: Adult patients with small, unrepaired atrial septal defects have an in‐ creased risk of pneumonia, atrial fibrillation, and stroke. Furthermore, they have higher late mortality than the background population. The functional capacity is un‐ known in these patients. Therefore, our objective was to determine exercise capacity in adult patients diagnosed with an unrepaired atrial septal defect compared to healthy controls. Design: A cross‐sectional study. Patients: Adult patients with small, unrepaired atrial septal defects, aged 18‐65, di‐ agnosed between 1953 and 2011. Interventions: Cardiopulmonary exercise test was performed using an incremental bicycle test and gas… More >

  • Open Access

    ARTICLE

    A restrictive ventilatory pattern is common in patients with univentricular heart after Fontan palliation and associated with a reduced exercise capacity and quality of life

    Alessia Callegari1,2,4, Rhoia Neidenbach2, Ornella Milanesi1, Biagio Castaldi1, Martin Christmann4, Masamichi Ono3, Jan Müller2, Peter Ewert2, Alfred Hager2

    Congenital Heart Disease, Vol.14, No.2, pp. 147-155, 2019, DOI:10.1111/chd.12694

    Abstract Aim: The Fontan circulation is highly dependent on ventilation, improving pulmonary blood flow and cardiac output. A reduced ventilatory function is reported in these patients. The extent of this impairment and its relation to exercise capacity and qual‐ ity of life is unknown and objective of this study.
    Methods: This multicenter retrospective/cross‐sectional study included 232 patients (140 females, age 25.6 ± 10.8 years) after Fontan palliation (19.8% atrioventricular connection; 20.3% atriopulmonary connection; 59.9% total cavopulmonary connec‐ tion). Resting spirometry, cardiopulmonary exercise tests, and quality‐of‐life assess‐ ment (SF‐36 questionnaire) were performed between 2003 and 2015.
    Results: Overall, mean forced… More >

  • Open Access

    ARTICLE

    Production Capacity Evaluation of Horizontal Shale Gas Wells in Fuling District

    Jingyi Wang1, Jing Sun1,*, Dehua Liu1, Xiang Zhu1

    FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 613-625, 2019, DOI:10.32604/fdmp.2019.08782

    Abstract One of the important indicators of shale gas reservoir excavation is capacity evaluation, which directly affects whether large-scale shale gas reservoirs can be excavated. Capacity evaluation is the basis of system analysis and dynamic prediction. Therefore, it is particularly important to conduct capacity evaluation studies on shale gas horizontal wells. In order to accurately evaluate the horizontal well productivity of shale gas staged fracturing, this paper uses a new method to evaluate the productivity of Fuling shale gas. The new method is aimed at the dynamic difference of horizontal wells and effectively analyzes the massive More >

Displaying 101-110 on page 11 of 140. Per Page