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Journal of Central South University 2019年第5期26卷 1065-1076页

作者： hamid reza talesh bahrami Alireza AZIZI hamid SAFFARI School of Mechanical Engineering Iran University of Science and Technology

Condensation is an important regime of heat transfer which has wide applications in different industries such as power plants,heating,ventilating and air conditioning,and *** occurs in two different modes including filmwise (FWC) and dropwise (DWC) *** occurring on hydrophobic and superhydrophobic surfaces has a much higher heat transfer capacity than ***,wide investigations have been done to produce DWC in recent *** surfaces have micro/nano structures with low surface *** this study,a two-step electrodeposition process is used to produce micro/nano structures on copper *** surface energy of specimens is reduced by a self-assembled monolayer using ethanol and 1-octadecanethiol *** results show that there is an optimum condition for electrodeposition *** example,a surface prepared by 2000 s step time has 5 times greater heat transfer than FWC while a surface with 4000 s step time has nearly the same heat transfer as *** surfaces of the fabricated specimens are examined using XRD and SEM *** SEM analyses of the surfaces show that there are some micro-structures on the surfaces and the surface porosities are reduced by increasing the second step electrodeposition time.

关键词： dropwise condensation heat transfer electrodeposition micro/nano structure porosity

Numerical analysis on forced convection enhancement in an annulus using porous ribs and nanoparticle addition to base fluid

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Journal of Central South University 2019年第5期26卷 1089-1098页

作者： Majid SIAVASHI hamid reza talesh bahrami Ehsan AMINIAN hamid SAFFARI School of Mechanical Engineering Iran University of Science and Technology

Miniaturization of electronic equipment has forced researchers to devise more effective methods for dissipating the generated heat in these *** this study,two methods,including porous media inserting and adding nanoparticles to the base fluid,are used to improve heat transfer in an annulus heated on both *** study porous media insert,porous ribs are used on the outer and inner walls *** results show that when porous ribs are placed on the outer wall,although the heat transfer enhances,the pressure drop increment is so considerable that performance number (the ratio of heat transfer enhancement pressure increment,PN) is less than unity for all porous rib heights and porous media permeabilities that are *** the other hand,the PN of cases where porous ribs were placed on the inner wall depends on the Darcy number (Da).For example,for ribs with Da=0.1 and Da=0.0001,the maximum performance number,PN=4,occurs at the porous ribs height to hydraulic diameter ratios H/Dh=1 and H/Dh=*** these conditions,heat transfer is enhanced by two orders of *** is found that adding 5% nanoparticles to the base fluid in the two aforementioned cases improves the Nusselt number and PN by 10%–40%.

关键词： nanofluid porous media annulus heat transfer enhancement internal flow

Numerical investigation of flow and heat transfer behind a two-dimensional backward-facing step equipped with a semi-porous baffle

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Journal of Central South University 2021年第11期28卷 3354-3367页

作者： hamid-reza bahrami Department of Mechanical Engineering Qom University of TechnologyQom 37195Iran

The backward-facing step is a critical problem existing in many engineering and industrial *** this study,a semi-porous baffle(the root of the baffle is a porous medium and the tip is solid) is placed behind the *** effects of the length of the porous part,and the baffle location on the energy transfer and pressure drop are studied in different Reynolds numbers(Re=100,200,300,400,500).The effect of the Darcy number of the porous medium on the aforementioned parameters is also *** the local maximum and average relative Nusselt numbers(divided by the Nusselt of the base case with no baffle at the same Reynolds) and relative pressure drop(calculated as the relative Nusselt number) are *** results show that by adoption of the proper length of the porous medium,the average relative and maximum local Nusselt numbers could be enhanced by 20% and 90%,*** permeable porous media give better energy *** example,porous media with Da=10^(-5) give 30% better maximum local Nusselt number and about 7% higher average Nusselt number with respect to the same case with Da=10^(-2).

关键词： porous media enhanced heat transfer baffle backward-facing step two-dimensional channel

User Selection and Precoding Schemes Based on Partial Channel Information for Broadcast MIMO Systems

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International Journal of Communications, Network and System Sciences 2010年第4期3卷 339-349页

作者： hamid reza bahrami Tho Le-Ngoc 不详

Due to the large number of users and the time-varying characteristics of wireless channels, it is very tough to inform the transmitter of full channel information in real multi-user MIMO broadcast systems. On the other hand, the capacity of multi-user systems greatly depends on the knowledge of the channel at the transmitter while this is not always the case in single-user MIMO systems. In this paper, we investigate combined user selection and zero-forcing precoding schemes that use partial channel information, i.e., very low amount of channel information at the base station. We show that while greatly reducing the complexity and channel knowledge feedback load, the proposed schemes preserve the optimality of zero-forcing scheme in term of achievable ergodic sum capacity in limit of large number of active users.

关键词： Broadcast Channel Multi-User System Partial Channel Information Precoding

Maximum Ratio Combining Precoding for Multi-Antenna Relay Systems

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Communications and Network 2010年第2期2卷 97-103页

作者： hamid reza bahrami Tho Le-Ngoc 不详

This paper addresses the design of practical communication strategies for multi-antenna amplify-and-forward and decode-and-forward relay systems. We show that simple linear techniques at the source and destination in conjunction with maximum ratio combining can provide an optimal transmission strategy in terms of received SNR without imposing a huge computational load over the relay node(s). Besides, the structures of precoding matrices are very similar at the source and relay nodes, which reduces the complexity as all nodes can play the role of source and relay nodes without changing their transmission structure. Numerical results show that the proposed transmission and reception techniques can improve the received SNR, and hence enhance the ergodic capacity.

关键词： Cooperation Relay System Linear Precoding Maximum Ratio Combining

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伊朗传统医学的诊断方法

国际中医中药杂志 2009年第5期31卷 476-477页

作者： Hoda Azizi hamid reza bahrami-Taghanaki 薛晓欧北京中医药大学东直门医院妇科北京100700 Mashhad University of Medical Sciences Mashhad 91375-345 Iran

伊朗传统医学在理论基础、诊断和治疗方法等都有其特点。本文介绍伊朗传统医学的诊断方法。

关键词：传统医学诊断方法伊朗

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伊朗传统放血拔罐疗法的临床应用

国际中医中药杂志 2009年第4期31卷 358-359页

作者： hamid reza bahrami-Taghanaki Hoda Azizi 赵百孝北京中医药大学针灸学院北京100029 北京中医药大学附属东直门医院北京100700

本文介绍了伊朗传统医学中“放血拔罐”疗法的临床操作手法、施治部位、应用范围及注意事项等，使国内读者对伊朗的传统疗法有所认识，为各国传统医学的相互借鉴、交流提供资讯。

关键词：放血拔罐伊朗

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针刺对不同疾病患者血压与脉率的影响

国际中医中药杂志 2010年第2期32卷 136-137页

作者： Hoda Azizi hamid reza bahrami-Taghanaki 章正祥刘颖北京中医药大学东直门医院妇科北京100700 北京中医药大学针灸学院2006级博士研究生北京100029 浙江中医药大学浙江省中医院神经内科杭州310006 北京中医药大学东直门医院针灸科北京100029

目的研究针刺对不同类型患者收缩压、舒张压和脉率的影响。方法对106名受试者在针刺前和起针后立即测量血压和脉率，并咨询有无高血压病史及针刺史，记录下取穴和中西医诊断结果，以便评估针刺不同穴位有不同疾病患者的血压和脉率的作... 详细信息

目的研究针刺对不同类型患者收缩压、舒张压和脉率的影响。方法对106名受试者在针刺前和起针后立即测量血压和脉率，并咨询有无高血压病史及针刺史，记录下取穴和中西医诊断结果，以便评估针刺不同穴位有不同疾病患者的血压和脉率的作用。结果针刺后收缩压、舒张压、脉率较针刺前均有不同程度的下降，且差异有统计学意义（P〈0．01）。针刺史和高血压病史可能不是针刺影响血压、脉率的因素（P〉0．05）。有些穴位与血压有关；有些穴位与脉率有关（P〈0．05或P〈0．01）。结论针刺某些穴位对血压和脉率有一定的影响。

关键词：收缩压舒张压脉率针刺

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针刺对20例单纯性肥胖症患者血糖的影响

中医研究 2009年第11期22卷 54-55页

作者： hamid reza bahrami-Taghanaki Hoda Azizi 朴联友章正祥北京中医药大学针灸学院北京100029 北京中医药大学东直门医院妇科北京100700 北京中医药大学东直门医院针灸科北京100700 浙江省中医院神经内科浙江杭州310006

目的:观察20例单纯性肥胖症患者针刺前后血糖的变化。方法:20例单纯性肥胖患者在基本穴的基础上辨证加减取穴,施以不同的补泻手法,留针25 min,并在针刺前后即刻测量血糖。结果:针刺后较治疗前血糖升高,差别具有统计学意义(P<0.05)。结论... 详细信息

目的:观察20例单纯性肥胖症患者针刺前后血糖的变化。方法:20例单纯性肥胖患者在基本穴的基础上辨证加减取穴,施以不同的补泻手法,留针25 min,并在针刺前后即刻测量血糖。结果:针刺后较治疗前血糖升高,差别具有统计学意义(P<0.05)。结论:针刺减肥与血糖不是一种简单的上调或下调关系,其作用机制有待于进一步研究证实。

关键词：单纯性肥胖/治疗针刺疗法血糖

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伊朗与中国放血拔罐方法之比较

中国民间疗法 2009年第6期17卷 61-62页

作者： hamid reza bahrami-Taghanaki Hoda Azizi 李涛赵百孝北京中医药大学 100029

放血拔罐法是放血与拔罐相结合的一种综合疗法，是由《灵枢·官针》论述的九针中的刺络发展而来。主要通过机械力、针刺和热因子等物理因子作用于机体，使气血通畅、散瘀消肿、祛除病邪，达到止痛并治疗疾病和健身目的。具有操作简便、... 详细信息

放血拔罐法是放血与拔罐相结合的一种综合疗法，是由《灵枢·官针》论述的九针中的刺络发展而来。主要通过机械力、针刺和热因子等物理因子作用于机体，使气血通畅、散瘀消肿、祛除病邪，达到止痛并治疗疾病和健身目的。具有操作简便、疗效显著、经济安全等独特优越性，且蕴涵着穴位刺激、引病外除、机械力调节、能量一信息调节等科学性，越来越受到国内外学者的关注，具有良好的发展前景。

关键词：拔罐方法放血中国伊朗物理因子信息调节灵枢·官针综合疗法