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Green Circuit Design for Battery-Free Sensors in Cloud Radio Access Network

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China Communications 2015年第11期12卷 1-11页

作者： ZENG Tengchan ma zhen WANG Gongpu ZHONG Zhangdui School of Electronic and Information Engineering Beijing Jiaotong University School of Computer and Information Technology Beijing Jiaotong University

Cloud radio access network(C-RAN)is considered as a promising approach to solve the bandwidth crunch problem for future wireless network. Another important element for future network is sensors that can monitor physical or environmental conditions. Currently,most sensors need batteries for power,which is energy-consuming and maintenance-heavy. To further improve energy effi ciency(EE) of sensors in C-RAN,this paper proposes a new structure as well as practical circuit design for green sensors in C-RAN. The structure can enable sensors to harvest energy from radio signals transmitted by neighbor remote radio heads(RRHs) and user terminals(UTs). To demonstrate the validity of the new structure,a practical circuit design is suggested and the corresponding hardware platform is realized. Specifically,selection criteria for electrical component parameters and design of an impedance-matching network are discussed in details. In addition,two methods to stabilize the output voltage are proposed and analyzed. Finally,simulation results as well as experimental results are provided to corroborate our proposed studies.

关键词： energy harvesting C-RAN batteryfree sensor energy eff iciency

Effect of fertilizer and water content on N_2O emission from three plantation soils in south China

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Journal of Environmental Sciences 2005年第6期17卷 970-976页

作者： LI Zhi-an ZOU Bi XIA Han-ping DING Yong-zhen TAN Wan-neng ma zhen-rong South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China

The effects of fertilizers and water content on N2O emission were studied using the three most typical plantation soils. Soil incubations were performed and fertilization and water content treatments were designed. At 25% of saturated water content（SWC）, N2O emissions from the soil treated with urea, KNO3, （NH4）2 SO, and KH2 PO, were compared at application rates of 0, 100, 200, 300 and 500 kg/hm2. At 80% of SWC, similar experiments were carried out but at only one application rate（500 kg/hm^2）. N2O emissions at various water contents（20%, 35%, 50%, 65%, 80% and 100% of SWC） were studied. At low water content（25% of SWC）, neither nitrogen nor phosphorus（or potassium） fertilizers led to a high level of N2O emission, which generally ranged from 2.03 to 29.02 μg/（m^2·h）. However, at high water content（80% SWC）, the fertilizers resulted in much greater N2O emission irregardless of soil tested. The highest N2O emission rates after 24 h of water addition were 1233 lag/（ m^2 ·h） for S. superba soil, 1507 lag/（m^2 · h） for P. elliottii soil and 1869 lag/ （m^2 h） for A. mangium soil respectively. N2O emission from soils treated with urea, （NH4）2SO, and KH2PO, immediately dropped to a low level but steadily increased to a very high level for the soil treated with KNO3. High NO3^- content was a basis of high level of N2O emission. N2O emission rates from soils peaked shortly after flooding, rapidly dropping to a very low level in soil from non-legume plantations, but lasting for a relatively long period in soil from legume plantations. When soil water content increased equaling to or higher than 65%, the accumulated N2O emission over a period of 13 d ranged from 20.21-29.78 mg/m^2 for S. superba, 30.57-70.12 mg/m^2 for P. elliottii and 300.89-430.51 mg/m^2 for A. mangium. The critical water content was 50% of SWC, above which a high level of N2O emission could be expected, and below which very little N2O emissions were detected. The results suggest that, at low water content（

关键词： N2O plantation south China Acacia mangium Pinus elliottii Schima superba

Size effects on springback behavior of H80 foils

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Rare Metals 2018年第12期37卷 1082-1090页

作者： zhen-Wu ma Zi-Yang Cao Jin-Bin Lu Yuan-Jing Zhang Wei Liu zhen Yin College of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China Suzhou Key Laboratory of Precision and Efficient machining Technology Suzhou 215009China

Size effects make traditional bending theories infeasible in analyzing the springback behavior of H80 foils in the similarity bending experiment. It is observed that there is a certain critical thickness value, which divides the change trend of springback amount of foils into two opposite parts. In order to reveal the reason for size effects on the springback behavior of H80 foils, the method of hardness increment characterization was applied to describe the deformation distribution of foils. The competition between strengthening effect of geometrically necessary dislocations and weakening effect of surface grains determines the change trend of springback amount with foil thickness. When the thickness of foils is large, the weakening effects dominate the material behavior, resulting in that the springback amount decreases with the decrease in foil thickness. However, when the foil thickness is small, the strengthening effects dominate the springback tendency, leading to a sharp increase in the springback amount. Furthermore, the deformation distribution is disturbed due to the enhanced effects of individual grain heterogeneity with the decrease in the thickness of foils, leading to the large scatter of springback angle after unloading.

关键词： Foil bending Springback behavior Size effects Hardness increment characterization

微气泡强化臭氧去除污水厂二级出水中的有机物

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中国给水排水 2024年第5期40卷 63-68页

作者：马振坤刘永泽张立秋封莉杜子文北京林业大学环境科学与工程学院水体污染源控制技术北京市重点实验室北京100083 北京林业大学环境科学与工程学院污染水体源控制与生态修复技术北京市高等学校工程研究中心北京100083

以实际污水厂二级出水为处理对象,对比不同臭氧曝气方式(微气泡曝气和常规曝气)对污水中有机物的去除效果,同时考察微气泡对臭氧传质以及自由基产生的强化能力。连续流动态实验结果表明,微气泡曝气(气泡直径d=10~150μm)与常规曝气(d>1 ... 详细信息

以实际污水厂二级出水为处理对象,对比不同臭氧曝气方式(微气泡曝气和常规曝气)对污水中有机物的去除效果,同时考察微气泡对臭氧传质以及自由基产生的强化能力。连续流动态实验结果表明,微气泡曝气(气泡直径d=10~150μm)与常规曝气(d>1 mm)分别在30和40 mg/L臭氧投量下达到最佳处理效果(COD<5 mg/L),此时O_(3)/COD(表征去除单位COD所需臭氧量)值分别为1.3和2.2,微气泡曝气可以显著降低处理成本。静态实验结果表明,当臭氧投量为3 mg/min时,微气泡曝气在5 min内可去除90.6%的COD,而常规曝气的去除率仅为75.4%。同时发现,反应过程中微气泡曝气的臭氧利用率达到100%,远高于常规曝气;微气泡曝气使臭氧传质系数从0.176 kmol/(m^(3)·h)提高到0.335 kmol/(m^(3)·h),·OH产量较常规曝气提高了1.9倍。

关键词：臭氧氧化微气泡再生水难降解有机物臭氧传质臭氧利用效率

壮医经筋疗法联合半夏白术天麻汤在椎动脉型颈椎病中的治疗作用研究

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中国医药科学 2024年第3期14卷 107-111页

作者：温勇马振李汶霜黄冰广西国际壮医医院壮医针灸推拿科广西南宁530201

目的观察壮医经筋疗法联合半夏白术天麻汤治疗椎动脉型颈椎病(CSA)的临床效果。方法选择2023年1—7月广西国际壮医医院针灸推拿科住院或门诊确诊为CSA的患者,共100例,按照随机数表法分为壮医经筋疗法联合半夏白术天麻汤组(治疗组)50... 详细信息

目的观察壮医经筋疗法联合半夏白术天麻汤治疗椎动脉型颈椎病(CSA)的临床效果。方法选择2023年1—7月广西国际壮医医院针灸推拿科住院或门诊确诊为CSA的患者,共100例,按照随机数表法分为壮医经筋疗法联合半夏白术天麻汤组(治疗组)50例、常规推拿+针刺组(对照组)50例。观察两组治疗前后临床症状及体征评分、颈椎DR(正侧位+开口位)、多普勒超声中对血流速度以及血液流变学指标的影响,比较两组临床疗效。结果治疗后观察组临床总有效率、VAS评分、椎动脉型症状积分、椎动脉与基底动脉平均血流速度、血液流变学指标、颈椎DR(正侧位+开口位)检查结果方面均优于对照组,差异有统计学意义(P <0.05)。结论壮医经筋疗法联合半夏白术天麻汤能明显改善患者的眩晕症状,同时能够改善患者脑部供血,在治疗CSA方面有显著效果,值得临床推广。

关键词：壮医经筋疗法半夏白术天麻汤椎动脉型颈椎病治疗作用

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残余废气系数对内燃机缸内热功转换性能影响的实验

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机械制造与自动化 2024年第3期53卷 109-112页

作者：车海威马震何嘉航西安爱生技术集团有限公司陕西西安710065 西北工业大学第365研究所陕西西安710065 航空工业一飞院陕西西安710089

为提高残余废气系数对内燃机缸内热功转换性能影响的研究,利用1台自然吸气单缸机开展台架测试,分析RGF引起的内燃机热功转换效果与排放特性变。研究结果表明:提高残余废气系数后,燃烧阶段快速单调升高。缸内残余废气可以起到稀释新鲜混... 详细信息

为提高残余废气系数对内燃机缸内热功转换性能影响的研究,利用1台自然吸气单缸机开展台架测试,分析RGF引起的内燃机热功转换效果与排放特性变。研究结果表明:提高残余废气系数后,燃烧阶段快速单调升高。缸内残余废气可以起到稀释新鲜混合气的效果,导致燃烧速率减小,从而引起燃烧持续期的快速升高。提高残余废气系数的过程中,由初始点火时刻到50%燃烧点都保持单调递增;当转速提高时,从点火到50%燃烧点的曲轴转角也明显升高。提高残余废气系数后,高压循环指示热效率表现为小幅升高。缸内燃烧温度与残余废气系数之间呈现负相关变化;50%燃烧点发生了燃烧恶化结果。本方法具有较高的预测精度,可大大降低传感器成本,具有很高的实际应用价值。

关键词：内燃机残余废气系数燃烧排放

Evaluation of casting fluidity and filling capacity of Zr-based amorphous metal melts

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Journal of Iron and Steel Research International 2018年第11期25卷 1163-1171页

作者： De-qiang ma Xiao-zhao ma Hong-yuan Zhang Ming-zhen ma Xin-yu Zhang Ri-ping Liu Department of Electromechanical Engineering Tangshan UniversityTangshan 063000HebeiChina State Key Laboratory of Metastable materials Science and Technology Yanshan UniversityQinhuangdao 066004 HebeiChina

Understanding the flow characteristics of amorphous metal melts is important for casting and molding *** of Zr-based amorphous metal melts was determined by using a self-designed *** analysis demonstrated that the fluidity test samples were fuUy amorphous *** onset crystallization temperature significantly moved toward high temperature with the increases of casting temperature,which improved the glass-forming ability and thermal stability of Zr-based amorphous *** test results demonstrated that the fluidity length increased monotonically with the increases of temperature,pressure,and runner *** identifying the types and quantities of the defect in castings,it could conclude that smooth filling processes occurred under appropriate *** results indicated that the flow behavior of the Zr-based amorphous metal melts strongly depended on the casting temperature and equivalent *** equation based on Newton's law of heat exchange and Rayleigh rule was established to'evaluate the fluidity of Zr-based amorphous metal *** calculations and experimental tests were basically coincided with each *** determined optimal casting temperatures and equivalent thicknesses were adopted to successfully fabricate a series of fully shaped castings through gravity casting.

关键词： Amorphous metal melt Casting Fluidity Constitutive equation Filling capacity

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专业集群下新工科机器人工程专业建设

电气电子教学学报 2024年第4期46卷 39-43页

作者：马震刘甜甜谢明山贵阳信息科技学院智能工程系贵阳550025 贵州大学大数据与信息工程学院贵阳550025

学科导向的单一专业人才培养体系已无法满足新时代社会发展需求。通过机器人工程专业建设现状分析,得出以专业集群为形态特征的领域工程技术人才培养体系能有效提高人才供给侧与产业需求侧的匹配度,依据产业需求对学科专业动态重构是新... 详细信息

学科导向的单一专业人才培养体系已无法满足新时代社会发展需求。通过机器人工程专业建设现状分析,得出以专业集群为形态特征的领域工程技术人才培养体系能有效提高人才供给侧与产业需求侧的匹配度,依据产业需求对学科专业动态重构是新工科建设应对新产业技术发展的有效途径。通过对机器人工程专业“先宽后深”的建设主线、“3+1”应用型人才培养模式介绍,为其他高校提供借鉴和启示。

关键词：专业集群机器人工程专业建设

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氧气浓缩器多参数测量装置的研制

北京生物医学工程 2024年第2期43卷 180-186页

作者：马振孟志平宋连有李娜北京市医疗器械检验研究院北京101111

目的研发一种氧气浓缩器的气体温度、压力、流量和氧气浓度的多参数测量装置,用于监测氧气浓缩器在标准YY 9706.269—2021中电磁兼容抗扰度实验时的基本性能。方法通过对氧气浓缩器电磁兼容抗扰度实验特点的分析,研发装置结构设计成回字... 详细信息

目的研发一种氧气浓缩器的气体温度、压力、流量和氧气浓度的多参数测量装置,用于监测氧气浓缩器在标准YY 9706.269—2021中电磁兼容抗扰度实验时的基本性能。方法通过对氧气浓缩器电磁兼容抗扰度实验特点的分析,研发装置结构设计成回字型,由温度传感器、压力传感器、可调节流阀、质量流量计、顺磁氧传感器、电源模块、数据采集器和数据记录软件组成,其中测量模块要求精度高、响应快、稳定性好,数据采集器要求分辨率高、采样率高,数据记录软件基于LabVIEW开发的检测应用程序。再使用标准气体、数字多用表和质量流量计等测量仪器,对研发装置进行氧气校正和准确性验证。同时根据标准YY 9706.269—2021条款202.***.2.1.10要求,选择医用分子筛制氧机作为样品进行电磁兼容抗扰度测试,使用研发装置监测样品的基本性能。结果研发装置的参数测量达到如下指标,温度的量程是0~100℃,压力的量程是0~200 kPa,流量的量程是0~15 L/min,氧气浓度的量程是0~100%;温度的准确度是±0.5℃,压力准确至所测值的±2%以内,流量准确至所测值的±2%以内,氧气浓度准确至所测值的±1%以内。结论研发装置能够准确测量氧气浓缩器的气体温度、压力、流量和氧气浓度,各个参数的测量结果以Excel文件形式保存。研发装置符合标准YY 9706.269—2021对氧气浓缩器在电磁兼容抗扰度实验的相关要求。

关键词：氧气浓缩器氧气浓度流量电磁兼容抗扰度