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Device-to-Device Communication Underlaying Cellular Communications Systems

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International Journal of Communications, Network and System Sciences 2009年第3期2卷 169-178页

作者： Pekka JANIS Chia-Hao YU klaus doppler Cassio RIBEIRO Carl WIJTING klaus HUGL Olav TIRKKONEN Visa KOIVUNEN Department of Communications and Networking Helsinki University of Technology Espoo Finland Department of Signal Processing and Acoustics Helsinki University of Technology Espoo Finland Nokia Research Center Nokia Group Helsinki Finland

In this article we propose to facilitate local peer-to-peer communication by a Device-to-Device (D2D) radio that operates as an underlay network to an IMT-Advanced cellular network. It is expected that local services may utilize mobile peer-to-peer communication instead of central server based communication for rich mul-timedia services. The main challenge of the underlay radio in a multi-cell environment is to limit the inter-ference to the cellular network while achieving a reasonable link budget for the D2D radio. We propose a novel power control mechanism for D2D connections that share cellular uplink resources. The mechanism limits the maximum D2D transmit power utilizing cellular power control information of the devices in D2D communication. Thereby it enables underlaying D2D communication even in interference-limited networks with full load and without degrading the performance of the cellular network. Secondly, we study a single cell scenario consisting of a device communicating with the base station and two devices that communicate with each other. The results demonstrate that the D2D radio, sharing the same resources as the cellular net-work, can provide higher capacity (sum rate) compared to pure cellular communication where all the data is transmitted through the base station.

关键词： Peer-to-Peer Device-to-Device Power Control Cellular Systems IMT-Advanced

The LIMMCAST Program at HZDR:Modelling of Fluid Flow and Transport Phenomena in the Continuous Casting Process

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Journal of Iron and Steel Research(International) 2012年第S1期19卷 1-8页

作者： Gerbeth Gunter Eckert Sven Stefani Frank Timmel klaus Wondrak Thomas Helmholtz-Zentrum Dresden-Rossendorf P.O.Box 51011901314 DresdenGermany

Model experiments with low melting point liquid metals are an important tool to investigate the flow structure and related transport processes in melt flows relevant for metallurgical *** present the new experimental facility LIMMCAST for modelling the continuous casting process of steel using the alloy SnBi at temperatures of 200-400℃.The parameters of the facility and the dimensions of the test sections will be given,and the possibilities for flow investigations in tundish,submerged entry nozzle and mould will be *** addition,the smaller set-up Mini-LIMMCAST will be presented,which works with the room-temperature liquid alloy *** main value of cold metal laboratory experiments consists in the capabilities to obtain quantitative flow measurements with a reasonable spatial and temporal *** ultrasonic and electromagnetic techniques for measuring the velocity in liquid metal flows came up during the last decade allowing for a satisfying characterisation of flow quantities in the considered temperature range up to 400℃.First results from LIMMCAST and Mini-LIMMCAST will be presented covering the following phenomena:fully contacfless electromagnetic tomography of the flow in the mould,flow monitoring by a multitude of ultrasonic sensors,and analysis of the flow in the mould under the influence of an electromagnetic brake: intensification of the flow turbulence contrary to the expected flow damping,injection of argon bubbles through the stopper rod:occurrence of pressure oscillations.

关键词： continuous casting liquid metal model mould flow flow measurements two-phase flow magnetic flow tomography ultrasound doppler method

Echo-enhanced ultrasound with pulse inversion imaging: A new imaging modality for the differentiation of cystic pancreatic tumours

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World Journal of Gastroenterology 2006年第14期12卷 2205-2208页

作者： Steffen Rickes klaus Mnkemüller Peter Malfertheiner Department of Gastroenterology Hepatology and Infectious Diseases Otto-von-Guericke-UniversityMagdeburgGermany

瞄准：在膀胱的胰腺的损害的鉴别诊断描述并且讨论提高回响的 sonography。方法：脉搏倒置技术(与 2.4 mL SonoVue 的静脉注射) 或在第二泛音成像的条件下面的 power-doppler 模式(与 4 g Levovist 的静脉注射) 被用于提高回响的 sonogr... 详细信息

瞄准：在膀胱的胰腺的损害的鉴别诊断描述并且讨论提高回响的 sonography。方法：脉搏倒置技术(与 2.4 mL SonoVue 的静脉注射) 或在第二泛音成像的条件下面的 power-doppler 模式(与 4 g Levovist 的静脉注射) 被用于提高回响的 sonography。结果：Cystadenomas 经常沿着纤维变性海滨显示出许多容器。在另一方面，包囊腺癌是糟糕并且混乱 vascularized。“年轻假包囊”经常被发现有一面高度脉管的 ised 墙。然而，“旧假包囊”的墙是糟糕 vascularized。从未来的研究的数据证明基于这些成像标准，在膀胱的胰腺的群众的区别的提高回响的 sonography 的敏感和特性是 >90% 。结论：膀胱的胰腺的群众在提高回响的 sonography 有一个不同血管形成模式。这些特征为他们的鉴别诊断是有用的，但是组织学仍然是标准答案。

关键词：超声检查胰腺肿瘤膀胱肿瘤检查方法

Experimental Modelling of the Impact of a DC Magnetic Field on the Melt Flow in a Continuous Casting Mould

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Journal of Iron and Steel Research(International) 2012年第S2期19卷 862-865页

作者： TIMMEL klaus WONDRAK Thomas RDER Michael STEFANI Frank ECKERT Sven GERBETH Gunther Helmholtz-Zentrum Dresden-Rossendorf

This paper describes experimental investigations of flow structures and related transport processes in the continuous casting mould under the influence of an external DC magnetic field at laboratory *** results will be presented here which have been obtained using a physical model(mini-LIMMCAST)operating with the low melting point alloy *** to the concept of the electromagnetic brake the impact of a DC magnetic field on the outlet flow from the Submerged Entry Nozzle(SEN)has been studied up to Hartmann numbers of about *** Ultrasound-doppler-Velocimetry(UDV)was applied for measurements of the flow pattern in the *** conductivity anemometers were used to measure the turbulent quantities of the *** effect of the magnetic field on the flow structure turned out to be manifold and rather *** magnetic field causes a deflection of the jet,at which the respective exit angle from the nozzle ports becomes more ***,both the penetration depth of the discharging flow into the lower part of the mould and the impinging velocity of the jet onto the side wall are reduced.A significant return flow occurs in the adjacent regions of the *** vortices are formed with axes being aligned with the magnetic field *** vortical structures are typical for quasi-two-dimensional magneto-hydrodynamic(MHD)*** flow measurements do not manifest a general braking effect which would be expected as an overall damping of the flow velocity and the related fluctuations all-over the mould *** of the wall conductivity showed a striking impact on the resulting flow structures.

关键词： continuous casting liquid metal model electromagnetic brake ultrasonic flow measurement potential probes

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中国黄海西岸海陆风循环结构研究

Atmospheric and Oceanic Science Letters 2021年第1期14卷 14-21页

作者： Yongxiang Ma Jinyuan Xin Xiaoling Zhang Lindong Dai klaus Schaefer Shigong Wang Yuesi Wang Zifa Wang Fangkun Wu Xinrui Wu Guangzhou Fan Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric SciencesChengdu University of Information TechnologyChengduChina State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjingChina

陆海风是由于海陆表面之间的比热容不同而导致的昼夜热量分布差异,从而在海岸附近引发的大气中尺度循环系统.本文利用多普勒风激光雷达Windcube100s首次对黄海西海岸的海陆风的循环结构进行了观测研究.在2018年8月31日至9月28日观测期... 详细信息

陆海风是由于海陆表面之间的比热容不同而导致的昼夜热量分布差异,从而在海岸附近引发的大气中尺度循环系统.本文利用多普勒风激光雷达Windcube100s首次对黄海西海岸的海陆风的循环结构进行了观测研究.在2018年8月31日至9月28日观测期间发现,海陆风发展高度一般在700 m至1300 m.海陆风转化持续的时间为6小时至8小时.在425m高度,海风水平风速出现最大值,平均为5.6 m s^(-1).陆风最大水平风速出现在370 m,约为4.5 ms^(-1).最大风切变指数在1300m处,为2.84;在陆风向海风转换过程中,最大风切变指数在700m处,为1.28.在同一高度上,风切变指数在海风盛行和陆风盛行时的差值范围为0.2-3.6,风切变能反映出海陆风的发展高度.

关键词：海陆风垂直风速循环结构多普勒风廓线激光雷达黄海

Role of endoscopic ultrasound in the characterization of solid pseudopapillary neoplasm of the pancreas

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World Journal of Gastrointestinal Endoscopy 2023年第4期15卷 273-284页

作者： Katarzyna M Pawlak Nadeem Tehami Ben Maher Shujaath Asif Krishn Kant Rawal Daniel Vasile Balaban Mohammed Tag-Adeen Fahd Ghalim Wael A Abbas Elsayed Ghoneem Khaled Ragab Mahmoud El-Ansary Shanil Kadir Sunil Amin Keith Siau Anna Wiechowska-Kozlowska klaus Mönkemüller Dalia Abdelfatah Abeer Abdellatef Sundeep Lakhtakia Hussein Hassan Okasha Endoscopy Unit Department of GastroenterologyHospital of The Ministry of Interior and AdministrationSzczecin 01-218Poland Interventional Endoscopy Unit University Hospital Southampton NHS Foundation Trust3AX POUnited Kingdom Consultant Gastroenterologist AIG HospitalsHyderabad 500032India Department of Gastroenterology Prime Institute of Digestive SciencesRajkot 360001India Department of Gastroenterology Central Military Emergency University HospitalCarol Davila University of Medicine and PharmacyBucharest 010011Romania Division of Gastroenterology and Hepatology Department of Internal MedicineQena Faculty of MedicineSouth Valley UniversityQena 83511Egypt Department of Endoscopy Shefa Al-Orman HospitalLuxor 85951Egypt Interventional Endoscopy Unit Sainte Marie HospitalOSNY 95520France Department of Internal Medicine Gastroenterology UnitFaculty of MedicineAssuit UniversityAssuit 71511Egypt Department of Gastroenterology and Hepatology Faculty of MedicineMansoura UniversityMansoura 35511Egypt Department of Hepatology and Gastroenterology Theodor Bilharz Research InstituteGiza 12511Egypt Department of Hepatology&Gastroenterology Theodor Bilharz Research InstituteGiza 12511Egypt Department of Gastroenterology Liaquat National Hospital&Medical CollegeKarachi 75900Pakistan

BACKGROUND Solid pseudopapillary neoplasm(SPN)is an uncommon pathology of the pancreas with unpredictable malignant *** ultrasound(EUS)assessment plays a vital role in lesion characterization and confirmation of the tissue ***,there is a paucity of data regarding the imaging assessment of these *** To determine the characteristic EUS features of SPN and define its role in preoperative *** This was an international,multicenter,retrospective,observational study of prospective cohorts from 7 large hepatopancreaticobiliary *** cases with postoperative histology of SPN were included in the *** collected included clinical,biochemical,histological and EUS *** One hundred and six patients with the diagnosis of SPN were *** mean age was 26 years(range 9 to 70 years),with female predominance(89.6%).The most frequent clinical presentation was abdominal pain(80/106;75.5%).The mean diameter of the lesion was 53.7 mm(range 15 to 130 mm),with the slight predominant location in the head of the pancreas(44/106;41.5%).The majority of lesions presented with solid imaging features(59/106;55.7%)although 33.0%(35/106)had mixed solid/cystic characteristics and 11.3%(12/106)had cystic *** was observed in only 4(3.8%)*** pancreatic duct dilation was uncommon,evident in only 2 cases(1.9%),whilst common bile duct dilation was observed in 5(11.3%)*** patient demonstrated a double duct sign at *** and doppler evaluation demonstrated inconsistent appearances with no emergence of a predictable *** guided biopsy was performed using three different types of needles:Fine needle aspiration(67/106;63.2%),fine needle biopsy(37/106;34.9%),and Sonar Trucut(2/106;1.9%).The diagnosis was conclusive in 103(97.2%)***-seven patients were treated surgically(91.5%)and the post-surgical SPN diagnosis was confirmed in all *** the 2-year

关键词： Solid pseudopapillary neoplasm SPN Frantz tumor Endoscopic ultrasound features EUSguided biopsy Fine needle aspiration/biopsy

开颅手术中动脉CO2分压和七氟烷对毛细血管静脉脑血流和氧饱和度的影响

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麻醉与镇痛 2011年第6期7卷 50-55页

作者： Departments of klaus Ulrich Klein, MD Martin Glaser, MD Robert Reisch, MD, PhD Achim Tresch, MSc Christian Werner, MD, PhD Kristin EngeLhard, MD, PhD 刘鲲鹏（译）李成辉（校） Departments of AnesthesiologyLudwig-Maximilians-University Munich Germany Departments ofNeurosurgery Johannes Gutenberg-University MainzGermanyLudwig-Maximilians-University Munich Germany Departmentof Chemistry and Biochemistry Gene Center MunichLudwig-Maximilians-University Munich Germany 不详

背景手术中常规监测脑血流和氧饱和度是一项技术上的挑战。基于脑血管对CO，反应性的生理学原理．我们对新近开发的一种神经监测仪（oxygen—to—see，O2CTM）在开颅手术患者同步监测毛细血管静脉局部脑血流量（rvCBF）、血流速度（rvV... 详细信息

背景手术中常规监测脑血流和氧饱和度是一项技术上的挑战。基于脑血管对CO，反应性的生理学原理．我们对新近开发的一种神经监测仪（oxygen—to—see，O2CTM）在开颅手术患者同步监测毛细血管静脉局部脑血流量（rvCBF）、血流速度（rvVelo）、氧饱和度（srvO2）和血红蛋白计数（rvHb）方面的表现进行评估。方法26例实施神经外科手术的患者，随机分g4采用呼气术浓度为1．4％和2．O％七氟烷进行麻醉。在颅骨切开后，在邻近手术部位肉眼所视正常的脑组织表面放置一光纤探头。每例患者同步监测较低动脉二氧化碳分压（PaCO2=35mmHg）和较高二氧化碳分压（PaC0，=45mmHg）时（随机排序）脑深度2mm和8mm处的组织脑血流。联合应用激光多普勒血流监测仪（rVcBF，rvVdo）和分光光度计（srvO，，rvHb）进行测量。采用线性模型检验较低和较高PaCO2、1.4％和2，0％呼气末七氟炕浓度2mm和8mm脑深度时rvCBF、rvVelo、srvO，和rvHb数值变化的线性关系。结果在脑组织深度2mm和8mm处，rvCBF和rvVelo随PaCO2升高而增加，与七氟皖浓度无关（P〈Q001）。高PaCO2使平均srvO2由50％升高至68％（P〈0．001）。与脑深度2mm处相比，脑深度8mm处的rvVelo（P〈0．001）和srvO，（P=0．007）较高。RvHb不受PaCO2变化的影响，但是与七氟垸浓度呈正相关（P=0．005）。结论PaCO：导致rvCBF和rvVelo增加，表明在呼气末七氟皖浓度1．4％和2％麻醉下，CO2增多可引起保护性血管扩张。SrvO2的连续升高表明PaCO2增高可导致脑动脉-静脉氧差缩小。RvHb不变表示测量期间未发生血液丢失。本研究显示，该神经监测仪可监测脑微血管主要静脉在不同PaCO2水平脑血流和氧饱和度的局部变化。

关键词：局部脑血流量 CO2分压氧饱和度毛细血管开颅手术七氟烷静脉动脉二氧化碳分压