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Water Science and Engineering 2023年第4期16卷 419-428页

作者： Qin Ke Ming-chao Li Qiu-bing Ren Wen-chao Zhao State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300350China bei fang investigation Design&Research Co.LtdTianjin 300222China

Numerical simulation of concrete-faced rockfill dams(CFRDs)considering the spatial variability of rockfill has become a popular research topic in recent *** order to determine uncertain rockfill properties efficiently and reliably,this study developed an uncertainty inversion analysis method for rockfill material parameters using the stacking ensemble strategy and Jaya *** comprehensive implementation process of the proposed model was described with an illustrative CFRD ***,the surrogate model method using the stacking ensemble algorithm was used to conduct the Monte Carlo stochastic finite element calculations with reduced computational cost and improved ***,the Jaya algorithm was used to inversely calculate the combination of the coefficient of variation of rockfill material *** optimizer obtained higher accuracy and more significant uncertainty reduction than traditional ***,the developed model effectively identified the random parameters of rockfill *** study provided scientific references for uncertainty analysis of *** addition,the proposed method can be applied to other similar engineering structures.

关键词： CFRD Uncertainty inversion analysis Stochastic finite element Surrogate model Stacking ensemble Jaya algorithm

Numerical investigation on interaction between regular waves and a fully submerged horizontal cylinder

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Journal of Hydrodynamics 2023年第6期35卷 1101-1118页

作者： Cheng Zeng Yu-die Hu Yu-ran Yin Jie Zhou Ling-ling Wang College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China China Water Resources bei fang investigation Design and Research Co.LtdTianjin300222China College of Mechanics and Materials Hohai UniversityNanjing211100China

This paper presents a 2-D numerical investigation on interaction between regular waves and a fully submerged horizontal cylinder.A mathematical model of numerical wave tank with two-way fluid-solid interactions were developed and *** wave-induced vibrations of a single-degree-of-freedom cylinder were simulated at eleven gap ratios(d/a=8,10,12,14,16,18,20,22,24,28 and 32).Numerical results indicate that significant nonlinear characteristics are introduced into the originally linear waves with the presence of *** on the variation characteristics of cylinder vibration amplitude,the gap ratios can be divided into three ranges,i.e.,the uncertain range(8≤d/a≤14),quasi-linear range(14≤d/a≤20)and linear range(20≤d/a≤32).Under the same wave condition,the gap ratio does not affect the frequencies of vortex shedding and cylinder *** presence of the cylinder complicates the flow field and suppress the vortex shedding around the cylinder.

关键词： Numerical simulation linear wave wave-induced vibration gap ratio flow pattern

Prediction of Long-Term Extreme Response of Fish Cage Using Environmental Contour Method

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China Ocean Engineering 2021年第3期35卷 332-343页

作者： BAI Xiao-dong GUO Wei-wei YANG Can LUO Han-bing State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Department of Naval Architecture and Ocean Engineering Tianjin UniversityTianjin 300072China China Water Resources bei fang investigation Design and Research CO.LTDTianjin 300222China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

The fish cage design requires accurate predictions of long-term extreme loads and *** with the time-consuming full long-term analysis method integrating all the probability distribution of the short-term extremes,the environmental contour method gains much attention in predicting the long-term extreme values due to the less computational *** paper investigates the long-term extreme response of a fish cage using the environmental contour *** fish cage is numerically simulated based on the lumped-mass method and the curved beam *** on the one-dimensional(1D)and two-dimensional(2D)environmental contour,the extreme responses,including the surge and heave motions,mooring force,and vertical bending of the floater,are predicted for different return periods and compared with the full long-term analysis *** indicate that the 1D method greatly underestimates the extreme *** 2D environmental contour method with a higher percentile level,namely90%,provides reasonable estimations and seems to be suitable for the long-term value *** studies show that the mooring arrangement and the bending stiffness have great effects on the bending moment and the mooring force and the mooring line pre-tension has minor effects on the fish cage response.

关键词： fish cage long-term extreme value environmental contour method sensitivity analysis

On Factorization of Coupled Channel Scattering S Matrices

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Communications in Theoretical Physics 2007年第5X期48卷 901-907页

作者： fang Ke-Jie Department of Physics Peking University Bei jing 100871 China

We investigate the problem on how to factorize a coupled channel scattering S matrix into a product of simple S matrices. Simple S matrix solntions are found, respecting unitarity, analyticity and being real analytic.... 详细信息

关键词： ππ scattering S matrix

The Biological Research of Clinical Behavior of Laryngeal Cancer

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Chinese Medical Sciences Journal 2003年第2期18卷 92-92页

作者：于永强董卫东李欣李树华周小榕 Depaytment of Otorhinolaryngology Bei Fang Hospital of ShenyangShenyang 110015

The present study analyzed the DNA content(ratio of heterploid,RH),s-phase cell(SPC)per-centage,the proliferating cell nuclear antigen(PC-NA) labelling index and area of nucleolar organizerregion (AgNOR) in 57 patient... 详细信息

关键词：喉癌临床分型实验室检查 RH SPC PCNA AgNOR 预后

The Dynamic Observation of Serum Level of SIL-2R and TNF in Maxillary Sinus Cancer

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Chinese Medical Sciences Journal 2001年第3期16卷 168-168页

作者：于永强 Department of Otorhinolaryngology Shen Yang Bei Fang Hospital Shenyang China

To investigate the relationship between tumor markers and maxillary sinus cancer, we studied 45 patients (male 33, female 12) with early maxillary sinus squamous cancer(T2 N 0 M 0). The average age of these patients was 53 years old. They were treated with local operation and afterward radiotherapy. Sixty-seven healthy people were recruited as control. The serum level of soluble interleukin-2 receptor (SIL-2R) and tumor necrosis factor (TNF) was determined by enzyme-linked immunosorbent assay (ELISA). The serum levels of SIL-2R and TNF in patients before treatment (455 ± 31.2; 106 ± 15.3)were significantly higher than those of the control group (396 ± 26; 67.8 ± 5.6), P ＜0.01 and also higher than those after treatment (387 ± 23.5; 71 ± 9.5), P＜ 0. 05. The serum levels of SIL-2R and TNF in patients who developed local recurrence increased dramatically (437 ± 23.5; 115 ± 7.2) and were significantly higher than those of patients who did not, P ＜ 0.01. This change often appeared about 3 months before we could detect local recurrence.

关键词：上颌窦鳞癌可溶性白细胞介素-2受体肿瘤坏死因子酶链免疫吸附试验血流动力学 SIL-2R TNF 血清肿瘤标志物

Model Checking Data Consistency for Cache Coherence Protocols

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Journal of Computer Science & Technology 2006年第5期21卷 765-775页

作者：潘宏林惠民吕毅 Laboratory for Computer Science Institute of Software Chinese Academy of Sciences Bei'jing 100080 P.R. China

A method for automatic verification of cache coherence protocols is presented, in which cache coherence protocols are modeled as concurrent value-passing processes, and control and data consistency requirement are described as formulas in first-order p-calculus. A model checker is employed to check if the protocol under investigation satisfies the required properties. Using this method a data consistency error has been revealed in a well-known cache coherence protocol. The error has been corrected, and the revised protocol has been shown free from data consistency error for any data domain size, by appealing to data independence technique.

关键词： concurrent systems cache coherence protocols value-passing symbolic transition graphs model checking

An investigation into the Effects of the Reynolds Number on High-Speed Trains Using a Low Temperature Wind Tunnel Test Facility

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Fluid Dynamics & Materials Processing 2020年第1期16卷 1-19页

作者： Yundong Han Dawei Chen Shaoqing Liu Gang Xu National Engineering Research Center for High-speed EMU CRRC Qingdao Si fang Co.Ltd.Qingdao266111China CRRC Qingdao Si fang Co. Ltd.Qingdao266111China

A series of tests have been conducted using a Cryogenic Wind Tunnel to study the effect of Reynolds number(Re)on the aerodynamic force and surface pressure experienced by a high speed *** test Reynolds number has been varied from 1 million to 10 million,which is the highest Reynolds number a wind tunnel has ever achieved for a train *** to our results,the drag coefficient of the leading car decreases with higher Reynolds number for yaw angles up to 30º.The drag force coefficient drops about 0.06 when Re is raised from 1 million to 10 *** side force is caused by the high pressure at the windward side and the low pressure generated by the vortex at the lee *** pressure distributions are not appreciably affected by Reynolds number changes at yaw angles up to 30°.The lift force coefficient increases with higher Re,though the change is *** a yaw angle of zero the down force coefficient is reduced by a scale factor of about 0.03 when the Reynolds number is raised over the considered *** higher yaw angles the lift force coefficient is reduced about *** to the side force coefficient,the rolling moment coefficient does not change much with *** magnitude of the pitching moment coefficient increases with higher *** indicates that the load on the front bogie is higher at higher Reynolds *** yawing moment coefficient increases with *** effect is more evident at higher yaw *** yawing moment coefficient increases by about 6%when Re is raised from 1 million to 10 *** influence of Re on the rolling moment coefficient around the leeward rail is relatively *** increases by about 2%over the considered range of Re.

关键词： High-speed train wind tunnel test reynolds number effect aerodynamic performance yaw angle

Numerical investigation of the Bowed Stator Effects in a Transonic Fan at LowReynolds Number

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Journal of Thermal Science 2017年第1期26卷 25-29页

作者： HUANG Enliang ZHAO Shengfeng GONG Jianbo LU Xingen ZHU Junqiang Key Laboratory of Light-duty Gas-turbine Institute of Engineering Thermophysics Chinese Academy of Sciences Bei-jing 100190 China

The performance of fan stage in a small turbofan engines is significantly affected at high-altitude low Reynolds number. In order to examine the effect of low Reynolds number on the fan stage, 3D numerical simulation method was employed to analyse the performance variations and the underlying flow structure in the fan stage. For the sake of decreasing the influence of low Reynolds number, the different bowed stator airfoils were redesigned and the effect of the modified design was evaluated.

关键词： Transonic Fan Low Reynolds Number Bowed Stator

ANALYTICAL SOLUTION OF GROUNDWATER FLUCTUATIONS IN ESTUARINE AQUIFER

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Journal of Hydrodynamics 2005年第5期17卷 641-646页

作者： CHEN Jing ZHOU Zhi-fang JIA Suo-bao College of Civil Engineering Hohai University Nanjing 210098 China Hydrology and Water Resources investigation Bureau of Jiangsu Province Nanjing 210029 China

As a basic factor in the environment of estuary, tidal effects in the coastal aquifer have recently attracted much attention because tidal dynamic also greatly influences the solute transport in the coastal aquifer. Previous studies on tidal dynamic of coastal aquifers have focused on the inland propagation of oceanic tides in the cross-shore direction, a configuration that is essentially one-dimensional. Two-dimensional analytical solutions for groundwater level fluctuation in recent papers are localized in presenting the effect of both oceanic tides and estuarine tides in quadrantal aquifer. A two-dimensional model of groundwater fluctuations in estuarine zone in proposed in this paper. Using complex transform, the two-dimensional flow equation subject to periodic boundary condition is changed into time-independent elliptic problem. Based on Green function method, an analytical solution for groundwater fluctuations in fan-shaped aquifer is derived. The response to of groundwater tidal loading in an estuary and ocean is discussed. The result show that its more extensive application than recent studies.

关键词： coastal aquifer analytical solution fanshaped area groundwater fluctuations Green function method estuary environment