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THE FLOW PROBLEM OF FLUIDS FLOW IN A FRACTAL RESERVOIR WITH DOUBLE POROSITY

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Applied Mathematics and Mechanics(English Edition) 2001年第10期22卷 1118-1126页

作者： TONG deng-ke(同登科) Zhang Hong-qing(张鸿庆) Department of Applied Mathematics Petroleum University East of China Dongying 257061 P R China Institute of Mathematical Science Dalian University of TechnologyDalian 116024 P R China

The effective radius of oil well is introduced in the inner boundary in the problem of fluids flow through fractal reservoir with double porosity, and thus a new model is established. Taking the wellbore storage and steady-state skin effect into consideration, the exact solutions of the pressure distribution of fluids flow in fractal reservoirs with double porosity are given for the cases of an infinite outer boundary, a finite closed outer boundary and a bounded domain with the constant pressure outer boundary conditions. The pressure behavior of fractal reservoir with double porosity is analyzed by using a numerical inversion of the Laplace transform solution. The pressure responses of changing various parameters are discussed.

关键词： fractal double porous media seepage well test analysis

脑电图检查在脑卒中诊疗过程中的应用研究进展

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中华神经医学杂志 2024年第8期23卷 859-864页

作者：赵杰李睿刘卫平刘宇琪邓柯白端阳西安医学院第一附属医院神经外科一病区西安710000 西安理工大学机械与精密仪器工程学院西安710000

脑电图检查为一种便捷、非侵入性技术,对脑功能异常高度敏感,目前已广泛应用于癫痫等多种神经系统疾病的诊疗过程中,在脑卒中领域的应用研究也有数十年历史。近年来,随着相关研究的不断深入和人工智能技术的快速发展,脑电图检查在脑卒... 详细信息

脑电图检查为一种便捷、非侵入性技术,对脑功能异常高度敏感,目前已广泛应用于癫痫等多种神经系统疾病的诊疗过程中,在脑卒中领域的应用研究也有数十年历史。近年来,随着相关研究的不断深入和人工智能技术的快速发展,脑电图检查在脑卒中的早期诊断、病情监测和预后评估方面展现出新的潜力和价值。本文现围绕近5年来脑电图检查在脑卒中诊断和病情评估、疗效评估及预后评估中的应用研究进展进行综述,并展望其在未来脑卒中管理中的潜在应用价值,以期为提高脑卒中的诊断准确性、优化治疗方案和改善患者预后提供参考依据。

关键词：脑卒中脑电图人工智能

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前置式蒸汽冷却器管系泄漏检测研究

电站辅机 2024年第2期45卷 27-31页

作者：樊进国邓科季敏东东方电气集团东方锅炉股份有限公司四川成都611731

前置式蒸汽冷却器是电站回热系统中的一个重要设备,位于回热系统给水流程的最后一级,它利用中压抽汽的过热度加热给水,进一步提高进入省煤器的给水温度。其壳侧为低压、高温的过热蒸汽,管侧为高压给水,管系泄漏会导致给水喷射到壳侧,高... 详细信息

前置式蒸汽冷却器是电站回热系统中的一个重要设备,位于回热系统给水流程的最后一级,它利用中压抽汽的过热度加热给水,进一步提高进入省煤器的给水温度。其壳侧为低压、高温的过热蒸汽,管侧为高压给水,管系泄漏会导致给水喷射到壳侧,高速流动的蒸汽裹挟给水水滴冲刷换热管,导致周围换热管损坏,影响设备寿命和换热能力。通过分析前置式蒸汽冷却器管系泄漏的类型和危急疏水排放类型,结合前置式蒸汽冷却器运行特点,提出了采用温差检测换热管泄漏的方法,简述了该方法的原理、组成和优点。温差检测换热管泄漏法相比常规的液位检测方法具有优势,可以低成本、快捷地检测前置蒸冷器管系泄漏。

关键词：蒸汽冷却器温差爆管管系泄漏控制

Two-Qubit Logic Gates and Teleportation of an Entangled State of Atom-Cavity with Cavity QED

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Communications in Theoretical Physics 2007年第4X期48卷 641-644页

作者： CHEN Ai-Xi HUANG ke-Lin deng Li Department of Applied Physics East China Jiaotong University Nanchang 330013 China

In this paper, a scheme is proposed for realization of two-qubit controlled-not gates and teleportation of an entangled state of atom-cavity. In this scheme, applying hyperfine levels of atom, we consider A-type three-level atom interacting resonantly or nonresonantly with cavity field that is prepared in σ- polarized. We consider the experimental feasibility of this scheme and compare our results with other schemes.

关键词： cavity QED entangled state teleportation

山地轨道交通隧道Geo-BIM建模方法与应用研究

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铁道标准设计 2024年第3期68卷 163-171页

作者：韩瑀萱邓科李想谭碧舸马春驰李天斌四川蜀道新制式轨道集团有限责任公司成都610041 成都理工大学地质灾害防治与地质环境保护国家重点实验室成都610059 四川都金山地轨道交通有限责任公司四川阿坝藏族羌族自治州623006

为解决山地轨道交通隧道在BIM建模中存在的隧道线路偏差大、隧道构件复杂繁多、属性添加效率低以及呈现效果单一等问题,提出一种基于Revit+Dynamo+Excel及EVS软件的山地轨道交通隧道Geo-BIM建模方法。结合隧道线性工程特点,对Revit内置D... 详细信息

为解决山地轨道交通隧道在BIM建模中存在的隧道线路偏差大、隧道构件复杂繁多、属性添加效率低以及呈现效果单一等问题,提出一种基于Revit+Dynamo+Excel及EVS软件的山地轨道交通隧道Geo-BIM建模方法。结合隧道线性工程特点,对Revit内置Dynamo插件二次开发,实现隧道快速精准的参数化建模和批量定义属性参数。提出基于EVS软件建立隧道三维地质体模型的方法,制定地层建模和岩性建模的实现方式和标准流程,结合隧道BIM模型全面实现隧道建设过程中的可视化。依托施家山隧道项目,基于Cesium框架实现了BIM模型、GIS地表和地质体三维模型的集成,实现三维可视化模型与模型属性、数据信息等可交互式操作。实践表明,Geo-BIM建模方法可以快速地对隧道BIM模型及其三维地质模型进行建模,通过集成后的模型信息之间能够表现出很好的交互效果,具有良好的工程应用价值。

关键词：山地轨道交通交通隧道 BIM模型三维地质体模型交互式操作

Current control for a shunt hybrid active power filter using recursive integral PI

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控制理论与应用（英文版） 2009年第1期7卷 77-80页

作者： Wei ZHAO An LUO ke PENG Xia deng College of Electrical and Information Engineering Hunan University Changsha Hunan 410082 China

This paper presents a current control method for a shunt hybrid active power filter （HAPF） using recursive integral PI algorithm. The method improves the performance of the HAPF system by reducing the influence of detection accuracy, time delay of instruction current calculation and phase displacement of output filter. Fuzzy logic based set-point weighing algorithm is combined in the control scheme to enhance its robustness and anti-interference ability. The proposed algorithm is easy to implement for engineering applications and easy to compute. Experiment results have verified the validity of the proposed controller. Furthermore, the proposed recursive integral PI algorithm can also be applied in the control of periodic current as in AC drivers.

关键词： Power electronics Shunt hybrid active power filter Recursive integral PI Fuzzy inference

Seasonal variability in free-living marine nematode community structure in a sandy beach of the Taiping Bay of Qingdao,China

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Acta Oceanologica Sinica 2008年第2期27卷 102-115页

作者： LIU Haibin ZHANG Zhinan FAN Shiliang HUA Er deng ke College of Marine Life Science Ocean University of China Qingdao 266003 China Liaoeheng Agriculture Bureau Liaocheng 252000 China

Nematode assemblage composition, trophic structure and biodiversity were followed over an annual cycle in a sandy beach of the Taiping Bay of Qingdao, China. Nematode assemblage in the sandy beach maintained a high genus diversity （75 genera）. Mlero- laimus and Bathylaimus were the dominant genus of the nematode assemblage, accounting for 66% of the total nematode abundance. The nematodes＇ dominant trophic structure changed seasonally as a response to the seasonal changes in food quality. Epigrowth-feeder nematodes （2A） were the dominant trophic groups in the trophic structure with the highest abundance in spring because of phytoplankton bloom, while the feeding type （ 1 B） showed higher abundance in summer that was due to the increasing of sediment detritus after spring bloom. Furthermore, species diversity and evenness calculated on nematodes identified to the genus level displayed significant temporal changes, which was also reflected by the index of trophic diversity. According to the cluster analysis, the nematode community structure of the whole year was clearly separated into two periods （A and B）. Biota-Envlron- ment matching （BIOENV） results showed that seawater temperature, sediment Chl a and grain size were responsible for the nema- tode community structure variation in spring and summer period （Period A）. However, seawater/interstitial water temperature, interstitial water dissolved oxygen concentration,interstitial water salinity, and sediment Ph a a were more important in constructing the autumn and winter period （Period B） nematode community structure.

关键词： nematode assemblage composition trophic structure temporal change Taiping Bay of Qingdao

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基于细菌避障策略的无人艇集群自主巡航方法

指挥控制与仿真 2024年第1期46卷 21-29页

作者：郑钰鹏邓科刘昊胡启智珠海云洲智能科技股份有限公司南方海洋科学与工程广东省实验室(珠海) 广东珠海519082 云洲创新科技有限公司深圳研究院广东深圳518106

针对无人艇集群执行巡航任务中的避障问题,提出了一种动态避障算法。首先,获取无人艇周边水域的方形网格轨迹单元态势矩阵;然后,借鉴细菌游走觅食原理,在方形网格轨迹单元集合中,动态匹配最佳避障路径;最后,在动态避障基础上,将无人艇... 详细信息

针对无人艇集群执行巡航任务中的避障问题,提出了一种动态避障算法。首先,获取无人艇周边水域的方形网格轨迹单元态势矩阵;然后,借鉴细菌游走觅食原理,在方形网格轨迹单元集合中,动态匹配最佳避障路径;最后,在动态避障基础上,将无人艇自主巡航过程划分为向目标行进、动态避障、返航补给等阶段,实现无人艇集群对划定水域的常态化巡航。仿真实验结果表明,所提方法对静态点、面障碍以及移动障碍均具有高效的规避能力,在算法基础上,能够实现无人艇集群的常态化无人值守巡航。该算法不仅适合无人艇的避障问题,在其他异构无人装备中也具有广阔的应用前景。

关键词：无人艇动态避障细菌游走方形网格轨迹单元自主巡航

Imaging presentation of biliary adenofibroma:A case report

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World Journal of Clinical Cases 2022年第4期10卷 1366-1372页

作者： Shao-Peng Li Peng Wang ke-Xue deng Department of Radiology The First Affiliated Hospital of University of Science and Technology of China(Southern District of Anhui Provincial Hospital)Hefei 230022Anhui ProvinceChina

BACKGROUND Biliary adenofibroma(BF)is a rare benign epithelial tumor with the possibility of malignant *** main pathological feature is a well-defined cystic or honeycomb *** has no specific clinical manifestations or laboratory and imaging findings;thus,it is easily misdiagnosed before *** report describes a case in which biliary cystadenoma was misdiagnosed preoperatively and BF was diagnosed *** imaging features,particularly the magnetic resonance imaging(MRI)features,were analyzed and *** SUMMARY A 68-year-old Chinese man was admitted to our hospital with a 2-mo history of abdominal *** admission to our hospital,laboratory examinations showed normal tumor marker concentrations and liver *** carcinoma was considered after contrast-enhanced ultrasound *** suggested the possibility of cystadenoma of the bile ***,postoperative pathological examination confirmed the diagnosis of *** local recurrence was found 1 mo after *** Our objective is to highlight the imaging diagnostic value of BF,especially on an MRI enhanced scan with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid.

关键词： Biliary adenofibroma Magnetic resonance imaging Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid Misdiagnosis Case report