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VORTEX INDUCED VIBRATIONS OF FINNED CYLINDERS

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Journal of Hydrodynamics 2008年第2期20卷 195-201页

作者： SHA yong wang yong-xue Postdoctoral Programme Technology Research Department CNOOC Research Beijing 100027 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024China

This article presents the results of a numerical simulation on the vortex induced vibration of various fumed cylinders at low Reynolds number. The non-dimensional, incompressible Navier-Stokes equations and continuity equation were adopted to simulate the fluid around the cylinder. The cylinder （with or without fins） in fluid flow was approximated as a mass-spring system. The fluid-body interaction of the cylinder with fins and uniform flow was numerically simulated by applying the displacement and stress iterative computation on the fluid-body interfaces. Both vortex structures and response amplitudes of cylinders with various arrangements of fins were analyzed and discussed. The remarkable decrease of response amplitude for the additions of Triangle60 fins and Quadrangle45 fins was found to be comparable with that of bare cylinder. However, the additions of Triangle00 fins and Quadrangle00 fins enhance the response amplitude greatly. Despite the assumption of two-dimensional laminar flow, the present study can give a good insight into the phenomena of cylinders with various arrangements of fins.

关键词： vortex induced vibration cylinder with fins fluid-body interaction

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基于胀套联接结构的传动滚筒静力分析

机械研究与应用 2024年第4期37卷 5-7,12页

作者：王学永曹玉华广东白云学院广东广州510450

为分析输送带张力对滚筒应力状态的影响,以带式散料输送机某一非标准传动滚筒为研究对象,建立了胀套联接结构形式传动滚筒的有限元分析模型,分别计算了仅考虑自重及胀套胀紧力条件下的应力与同时考虑自重、胀套胀紧力及输送带张力条件... 详细信息

为分析输送带张力对滚筒应力状态的影响,以带式散料输送机某一非标准传动滚筒为研究对象,建立了胀套联接结构形式传动滚筒的有限元分析模型,分别计算了仅考虑自重及胀套胀紧力条件下的应力与同时考虑自重、胀套胀紧力及输送带张力条件下的应力。计算结果显示传动滚筒的筒皮受输送带张力影响最大,其余部件受胀套胀紧力影响较大。

关键词：输送带张力传动滚筒胀套胀紧力静力分析

TIME-DOMAIN RESPONSES OF IMMERSING TUNNEL ELEMENT UNDER WAVE ACTIONS

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Journal of Hydrodynamics 2009年第6期21卷 739-749页

作者： CHEN Zhi-jie wang yong-xue wang Guo-yu HOU yong State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China CCCC-FHDI Engineering Co. Ltd Guangzhou 510230 China

The time domain responses of the tunnel element under wave actions during its immersion are investigated based on the linear wave diffraction theory. The integral equation is derived by using the time-domain Green function that satisfies the free water surface condition in the finite water depth, and is solved by the boundary element method. The motion equations of the tunnel element are solved by the fourth order Runge-Kutta method. A comparison between the computed and measured results reveals that the numerical model can effectively simulate the motion responses of the tunnel element and the cable tensions when the motions of the tunnel element are within some limit. Taking the tunnel element of 100 m in length, 15 m in width and 10 m in height as an example, the computational results of the motion responses of the tunnel element and the cable tensions in different immersing depths are obtained under different incident wave conditions.

关键词： Immersed tunnel time-domain response cable tension boundary element method

Evaluation of high-concentration sevoflurane for induction and nasotracheal intubation without muscle relaxant for infants with different pulmonary blood flow undergoing surgery for congenital heart diseases

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Chinese Medical Journal 2011年第24期124卷 4144-4148页

作者： wang Kai-yuan wang Hong-wu XIN Lian-feng wang yong-wang xue Yu-liang Department of Anesthesiology TEDA International CardiovascularHospital Tianjin 300457 China

Background Inhalational anesthesia with sevoflurane for endotracheal intubation without muscle relaxant is now used widely for pediatric patients. This study assessed the efficacy and safety of induction with high concentration sevoflurane and of nasotracheal intubation without muscle relaxant in infants with increased or decreased pulmonary blood flow （PBF） and undergoing surgery for congenital heart diseases. Methods Fifty-five infants aged 2-12 months, weighing 4.7-10.0 kg, and scheduled for congenital cardiac surgery were enrolled. Subjects were divided into those with increased （IPBF group, n--29） and decreased （DPBF group, n=26） pulmonary blood flow. All infants received inhalational induction with 8% sevoflurane in 100.0% oxygen at a gas flow rate of 6 L/min. Nasotracheal intubation was performed 4 minutes after induction. Sevoflurane vaporization was decreased to 4.0% for placement of a peripheral intravenous line and invasive hemodynamic monitors. Five minutes later, sedatives and muscle relaxant were administered and the vaporizer was adjusted to 2% for maintenance of anesthesia. Bispectral index （BIS） scores, circulatory parameters, satisfactory and successful intubation ratios, adverse reactions, and complications of intubation were recorded. Results Times to loss of lash and pain reflexes were longer for the DPBF group （P 〈0.01）. Satisfactory intubation ratios were 93.1% and 61.5% for the I PBF and DPBF groups, respectively （P=0.008）. Successful intubation ratios were 96.6% and 76.9% for the IPBF and DPBF groups, respectively （P=0.044）. Following sevoflurane inhalation, blood pressures decreased significantly in the IPBF group but remained stable in the DPBF group. BIS scores declined to similar stable values, and a ＂nadir BIS＂ was recorded for both groups. No obvious adverse reactions or complications of intubation were noted perioperatively. Conclusions Induction with high concentration sevoflurane, although faster for infants with IPBF, is safe

关键词： anesthetics, inhalation infant intubation, intratracheal heart defects, congenital

Fast Cross-Platform Binary Code Similarity Detection Framework Based on CFGs Taking Advantage of NLP and Inductive GNN

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Chinese Journal of Electronics 2024年第1期33卷 128-138页

作者： Jinxue PENG yong wang Jingfeng xue Zhenyan LIU School of Computer Science and Technology Beijing Institute of Technology

Cross-platform binary code similarity detection aims at detecting whether two or more pieces of binary code are similar or not. Existing approaches that combine control flow graphs(CFGs)-based function representation and graph convolutional network(GCN)-based similarity analysis are the best-performing ones. Due to a large amount of convolutional computation and the loss of structural information, the use of convolution networks will inevitably bring problems such as high overhead and sometimes inaccuracy. To address these issues, we propose a fast cross-platform binary code similarity detection framework that takes advantage of natural language processing(NLP)and inductive graph neural network(GNN) for basic blocks embedding and function representation respectively by simulating extracting structural features and temporal features. GNN’s node-centric and small batch is a suitable training way for large CFGs, it can greatly reduce computational overhead. Various NLP basic block embedding models and GNNs are evaluated. Experimental results show that the scheme with long short term memory(LSTM)for basic blocks embedding and inductive learning-based Graph SAGE(GAE) for function representation outperforms the state-of-the-art works. In our framework, we can take only 45% overhead. Improve efficiency significantly with a small performance trade-off.

关键词： Training Semantics Process control Binary codes Feature extraction Natural language processing Graph neural networks

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Environment-adaptive phase-separation-porous fluorofilm for highperformance passive radiation cooling

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Nano Research 2024年第6期17卷 5636-5644页

作者： Weiming Tang yong Li xue Meng Shutao wang Ziguang Zhao School of Future Technology University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Passive radiative cooling is widely recognized as an environmentally sustainable method for achieving significant cooling ***,the mechanical properties and environmental adaptability of current radiative cooling materials are not sufficient to maintain high cooling performance in external *** we reported an environment-adaptive phase-separation-porous fluorofilm for high-performance passive radiation *** to the homogenous fluoro-porous network with limited scattering efficiencies,we modulated the porous structure of the fluorofilm to achieve a strong emissivity of 95.2%(8-13μm)and a high reflectivity of 97.1%(0.3-2.5μm).The fluorofilm demonstrates a temperature drop of 10.5°C and an average cooling power of 81 W·m^(−2)under a sunlight power of 770 W·m^(−2).The high mechanical performance and environmental adaptability of fluorofilms are also *** its significant radiative cooling capability and robust environmental adaptability,the fluorofilm is expected to have a promising future in radiative temperature regulation.

关键词： fluorofilm passive radiation cooling porous optimization thermal regulation

Use of ultrasound to facilitate femoral nerve block with stimulating catheter

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Chinese Medical Journal 2011年第4期124卷 519-524页

作者： LI Min XU Ting HAN Wen-yong wang xue-dong JIA Dong-lin GUO Xiang-yang Department of Anesthesiology Peking University Third HospitalBeijing 100191 China

Background The adjunction of ultrasound to nerve stimulation has been proven to improve single-injection peripheral nerve block quality. However, few reports have been published determining whether ultrasound can facilitate continuous nerve blocks. In this study, we tested the hypothesis that the addition of ultrasound to nerve stimulation facilitates femoral nerve blocks with a stimulating *** In this prospective randomized study, patients receiving continuous femoral nerve blocks for total knee replacement were randomly assigned to either the ultrasound guidance combined with stimulating catheter group （USNS group; n=60） or the stimulating catheter alone group （NS group; n=60）. The primary end point was the procedure time （defined as the time from first needle contact with the skin until correct catheter placement）. The numbers of needle passes and catheter insertions, onset and quality of femoral nerve blocks, postoperative pain score, and early knee function were also *** The procedure time was significantly less in the USNS group than in the NS group （9.0 （6.0-22.8） minutes vs.13.5 （6.0-35.9） minutes, P=0.024）. The numbers of needle passes and catheter insertions were also significantly less in the USNS group. A greater complete block rate was achieved at 30 minutes in the USNS group （63.3% vs. 38.3%;P=0.010）. The postoperative pain score, the number of patients who required bolus local anesthetic and intravenous patient-controlled analgesia, and knee flexion on the second postoperative day were not significantly different between the two groups of *** Ultrasound-assisted placement of a stimulating catheter for femoral nerve blocks decreases the time necessary to perform the block compared with just the nerve-stimulating technique. In addition, a more complete blockade is achieved using the ultrasound-assisted technique.

关键词： ultrasonography nerve block catheterization

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乐清湾海域浮游动物群落结构时空变化研究

安徽农业科学 2024年第10期52卷 109-112,119页

作者：沈小飞王咏雪陈利路建林陈军陈德慧华能(浙江)能源开发有限公司玉环分公司浙江台州317600 台州市排污权储备中心浙江台州318000 温州市环境科技有限公司浙江温州325000 华能(浙江)能源开发有限公司清洁能源分公司浙江杭州310000 杭州希澳环境科技有限公司浙江杭州310000 杭州海蛞蝓生态科技有限公司浙江杭州310000

以2021年2月(冬季)和8月(夏季)乐清湾海域的调查数据为基础,分析调查海域浮游动物群落结构的时空变化特征。结果表明:乐清湾海域浮游动物群落结构具有明显的季节变化,8月(夏季)浮游动物种类数、生物量、丰度和物种多样性指数均明显高于2... 详细信息

以2021年2月(冬季)和8月(夏季)乐清湾海域的调查数据为基础,分析调查海域浮游动物群落结构的时空变化特征。结果表明:乐清湾海域浮游动物群落结构具有明显的季节变化,8月(夏季)浮游动物种类数、生物量、丰度和物种多样性指数均明显高于2月(冬季),2个季节群落结构的差异主要来源于水母类和浮游幼虫2个类群;在空间分布上,乐清湾内湾海域浮游动物群落结构与中湾、外湾海域显示出一定的差异性,外湾至内湾海域浮游动物生物量和丰度总体呈降低趋势,中湾海域和外湾海域的空间差异则较小,这表明乐清湾华能玉环电厂和浙能乐清电厂这2个电厂温排水未对整个乐清湾海域浮游动物群落结构产生较大影响,其影响可能主要集中在紧邻温排水口的海域。

关键词：浮游动物群落结构温排水时空变化乐清湾海域

Experimental investigation of motion responses of tunnel element immerging by moored barge

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Journal of Hydrodynamics 2015年第6期27卷 857-864页

作者：左卫广王永学 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

In this paper, the barge effect on the motion responses of the ttmnel element immerging by the moored barge under waves is investigated experimentally. Both the motion responses of the tunnel element and the moored barge in the experiment are simultaneously acquired by the Untouched 6-D Measurement System. The results show that the sway motion responses of the tunnel element immerging by the moored barge are different from those without the barge. For the system of the tunnel element and the moored barge, the moored barge has two motion components in the sway direction. The high frequency motion of the moored barge has little effect on the high frequency motion of the tunnel element with moored barge. However, the low frequency motion of the moored barge has a significant effect on the sway motion of the tunnel element. The motion responses of the tunnel element and the barge in the heave and roll directions are mainly the high frequency motion.

关键词： tunnel element moored barge motion responses low frequency motion maximum offset