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Physical Layer Security Performance Analysis in Multi-Antenna NOMA-Based UAV Relay Networks

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China Communications 2024年第9期21卷 98-108页

作者： Huang Haiyan Zhang Hongsheng liang linlin Li Yahong School of Electronic and Information Engineering Lanzhou Jiaotong UniversityLanZhou 730070China School of Cyber Engineering Xidian UniversityXi’an 710071China

With the increasing number of communication devices and the complexity of communication environments,unmanned aerial vehicles(UAV),due to their flexible deployment and convenient networking capabilities,have shown significant advantages in tasks such as high-density communication areas and emergency rescue within special communication *** the openness of air-toground wireless communication,it is more susceptible to eavesdropping *** a result,the introduction of physical layer security(PLS)in UAV communication systems is crucial to safeguard the security of transmitted *** this paper,we investigate the PLS issues in a UAV cooperative communication system operating in Nakagami-m fading channels with the presence of friendly *** considers the effects of imperfect successive interference cancellation(i SIC)and power allocation coefficients on system performance based on non-orthogonal multiple access(NOMA)*** deriving closed-form expressions for the outage probabilities at the receiving users and the intercept probability of UAV eavesdropper(U-EAV),the performance of the considered cooperative UAV-assisted NOMA relay system with the presence of friendly interference is evaluated.

关键词： intercept probability NOMA outage

Effect of repeated gonadotropin stimulation on ovarian reserves and proliferation of ovarian surface epithelium in mice

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Frontiers of Medicine 2009年第2期3卷 220-226页

作者： linlin liang Bei XU Guijin ZHU Reproductive Medicine Center Tongji HospitalTongji Medicine CollegeHuazhong University of Science and TechnologyWuhan 430030China

This study aimed to evaluate the effect of repeated ovarian stimulation(OS)on the ovarian follicular population and morphology in female mice and its inﬂuence on the embryo’s developmental ability,and the proﬁle of the ovarian surface epithelium(OSE).A total of 75 mice were enrolled in this experiment and randomly assigned into three groups:repeated ovarian stimulated group[n=25;receiving 5 IU pregnant mare serum gonadotrophin(PMSG)and human chorionic gonadotro-pin(hCG)at 6 day intervals for 5 cycles];single ovarian stimulated group(n=25;receiving 5 IU PMSG and hCG for 1 cycle),and control group(n=25;without additional treatment).The follicle number at various stages and the morphologies were recorded respectively in the three *** harvested oocytes or embryos,cleavage rate,good quality embryo rate,and blastocyst production rate were counted and calculated,and the proliferations of ovarian surface epithelium were evaluated *** the three groups,the single ovarian stimulation treatment signiﬁcantly increased the mean number of ovarian oocytes or embryos(39.25�10.77 one-cell embryos/female);on the other hand,repeated gonadotropin stimulation obtained the lowest mean number(5.15�2.81 eggs/female,P<0.01).Repeated ovarian stimulation also tended to decrease normal follicles of primary follicles(66.67%)and secondary follicles(72.86%),and got the lowest cleavage rate(67.47%),lowest good quality embryo rate(2.41%),and lowest blastocyst production rate(0).The OSE cells adjacent to the antral follicles and corpus luteum(CL)in the repeated ovarian stimulated group(81.8%)had a signiﬁcantly higher proliferation rate than the other *** proliferation rate of the OSE in the single ovarian stimulated group(56.4%)was signiﬁ-cantly higher than that in the control group(37.5%)(P<0.01).In conclusion,single ovarian stimulation may produce more oocytes/***,repeated gona-dotropin stimulation may have a negative effect on the ovarian follicular quality,th

关键词： gonadotropin-releasing hormone ovarian reserve embryo developmental ability ovarian surface epithelium

Effective Nucleic Acid Contamination Disinfection in Laboratory Settings using Ozone Gas

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Biomedical and Environmental Sciences 2024年第9期37卷 1095-1100页

作者： Yingyi Long linlin liang Xingyan Zhou Fei Ren Lu Wang Peng Zhang Jing Wang Department of Laboratory The Second People’s Hospital of Jiulongpo DistrictChongqing 400030China Jiulongpo District Center for Disease Control and Prevention Chongqing 400030China

The Nucleic Acid Laboratory,a division of the Clinical Laboratory Department,is responsible for performing real-time PCR(qPCR)assays to rapidly detect infectious diseases,genetic disorders,and more[1].As the gold standard,qPCR has played an indispensable role in diagnosing pandemic infections,such as the coronavirus disease 2019(COVID-19)[2].

关键词： qPCR indispensable performing

Origins of black carbon from anthropogenic emissions and open biomass burning transported to Xishuangbanna, Southwest China

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Journal of Environmental Sciences 2023年第3期125卷 277-289页

作者： Xuyan Liu SiwenWang Qianqian Zhang Chunlai Jiang linlin liang Shihao Tang Xingying Zhang Xiuzhen Han Lin Zhu National Satellite Meteorological Center Beijing 100081China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Department of Multiphase Chemistry Max Planck Institute for ChemistryMainz 55128Germany Research Center for Total Pollution Load Control and Emission Trading Chinese Academy of Environmental PlanningBeijing 100012China State Key Laboratory of Severe Weather and Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China

Black carbon(BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions(BCAn) and open biomass burning(BCBB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM_(2.5)concentrations of >75, 35–75, and<35 μg/m^(3), respectively. Results showed that the transport efficiency density(TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different *** yearly contributions to the effective emission intensity of BCAnand BCBBtransported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average BCAnand BCBBcontributions were 23% and 77%, respectively. This suggests that open biomass burning(BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of BCAntransported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to BCBBtransported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna.

关键词： Black carbon Xishuangbanna Effective emission intensity Anthropogenic emissions Open biomass burning

Formation of secondary inorganic aerosol in a frigid urban atmosphere

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Frontiers of Environmental Science & Engineering 2022年第2期16卷 39-50页

作者： Yuan Cheng Qinqin Yu Jiumeng Liu Youwen Sun linlin liang Zhenyu Du Guannan Geng Wanli Ma Hong Qi Qiang Zhang Kebin He State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China State Key Laboratory of Severe Weather&CMA Key Laboratory of Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China National Research Center for Environmental Analysis and Measurement Environmental Development Center of the Ministry of Ecology and EnvironmentBeijing 100029China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Department of Earth System Science Tsinghua UniversityBeijing 100084China

Formation of secondary inorganic aerosol(SIA)was investigated during a six-month long heating season in Harbin,*** sulfate formation was observed at high relative humidity(RH),with the same threshold RH(80%)for both colder and warmer measurement *** to wintertime results from Beijing,the threshold RH was considerably higher in Harbin,whereas the RH-dependent enhancement of sulfur oxidation ratio(SOR)was less *** addition,the high RH events were rarely encountered,and for other periods,the SOR were typically as low as~***,the sulfate formation was considered inefficient in this *** excluding the several cases with high RH,both SOR and the nitrogen oxidation ratio(NOR)exhibited increasing trends as the temperature increased,with the increase of NOR being *** nitrate to sulfate ratio tended to increase with increasing temperature as *** on a semi-quantitative approach,this trend was attributed primarily to the temperature-dependent variations of precursors including SO_(2) and NO_(2).The influence of biomass burning emissions on SIA formation was also *** stronger impact of biomass burning,an enhancement in NOR was observed whereas SOR was largely *** different patterns were identified as the dominant driver of the larger nitrate to sulfate ratios measured at higher concentrations of fine particulate matter.

关键词： Haze Sulfate Nitrate Heterogeneous chemistry Biomass burning

Influence of meteorological factors on open biomass burning at a background site in Northeast China

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Journal of Environmental Sciences 2024年第4期138卷 1-9页

作者： Yulong Wang linlin liang Wanyun Xu Chang Liu Hongbing Cheng Yusi Liu Gen Zhang Xiaobin Xu Dajiang Yu Peng Wang Qingli Song Jiumeng Liu Yuan Cheng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China Longfengshan Regional Background Station China Meteorological AdministrationHeilongjiang 150200China Heilongjiang Climate Center Heilongjiang 150030China

Biomass burning(BB)is a very important emission source that significantly adversely impacts regional air *** produces a large number of primary organic aerosol(POA)and black carbon(BC).Besides,BB also provides many precursors for secondary organic aerosol(SOA)*** this work,the ratio of levoglucosan(LG)to organic carbon(OC)and the fire hotspots map was used to identify the open biomass burning(OBB)events,which occurred in two representative episodes,October 13 to November 30,2020,and April1 to April 30,*** ratio of organic aerosol(OA)to reconstructed PM_(2.5)concentration(PM_(2.5)^(*))increased with the increase of LG/*** LG/OC ratio is higher than 0.03,the highest OA/PM_(2.5)^(*)ratio can reach 80%,which means the contribution of OBB to OA is *** to the ratio of LG to K^(+),LG to mannosan(MN)and the regional characteristics of Longfengshan,it can be determined that the crop residuals are the main *** occurrence of OBB coincides with farmers’preferred choices,i.e.,burning biomass in“bright weather”.The“bright weather”refers to the meteorological conditions with high temperature,low humidity,and without *** factors indirectly affect regional biomass combustion pollution by influencing farmers’active choices.

关键词： Air pollution Biomass burning Meteorological factors Organic trace Agricultural fires

Influence of High Relative Humidity on Secondary Organic Carbon: Observations at a Background Site in East China

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Journal of Meteorological Research 2019年第5期33卷 905-913页

作者： linlin liang Guenter ENGLING Yuan CHENG Xiaoye ZHANG Junying SUN Wanyun XU Chang LIU Gen ZHANG Hui XU Xuyan LIU Qianli MA State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512USA California Air Resources Board CA 91731USA School of Environment Harbin Institute of TechnologyHarbin 150001China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China Lin'an Regional Atmosphere Background Station Lin'an 311307China

To investigate the impacts of relative humidity(RH) on secondary organic aerosol(SOA) concentrations and chemical reactions, the carbonaceous aerosol components [i.e., organic carbon(OC) and element carbon(EC)] were quantified in daily PM2.5 samples collected at a background site in East China during summer 2015. Based on the method of EC-tracer, the concentration of secondary organic carbon(SOC) demonstrated an obvious negative relationship with RH higher than 60%. Moreover, the ratio of SOC/EC also exhibited obvious decreasing trends with increasing RH, indicating negative effects for chemical production of SOA under high RH conditions. Due to high RH,photochemistry was weakened, gaseous oxidant concentrations was lowered(e.g., significantly decreased O3 levels),and the production rates of SOA were relatively low. On the other hand, because of more water uptake under higher RH conditions, the aerosol droplet acidity was reduced and enhancement of SOA formation by acidity was accordingly absent. In addition, high RH also plays an important role in changing viscosity of pre-existing aerosol coatings,which can affect reactive uptake yield of SOA. Overall, the results from this study imply that SOA production may be more associated with photochemical processes, while aqueous-phase chemistry is not very important for some SOA formation in a moist ambient environment. In the ambient atmosphere, oxidant concentrations, reaction rates,airborne species, etc., are highly variable. How do these factors affect SOA yields under given ambient environment warrants further detailed investigations.

关键词： relative humidity organic aerosol secondary organic carbon(SOC) photochemistry aqueous-phase

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伪弹性形状记忆合金杆屈曲行为研究

应用力学学报 2020年第5期37卷 1935-1940,I0007页

作者：崔世堂梁琳琳中国科学技术大学中科院材料力学行为与设计重点实验室合肥230026 中国大唐集团科学技术研究院有限公司华东电力试验研究院合肥230022

对不同长细比伪弹性TiNi合金矩形截面杆进行了压缩试验,通过应变片和热电偶来捕捉杆中间截面表层材料的相变演化,采用热电偶测量杆中间截面受拉侧的温度,分析了长细比和材料相变对杆件承载能力的影响。结果表明:加载和卸载阶段,两端夹支... 详细信息

对不同长细比伪弹性TiNi合金矩形截面杆进行了压缩试验,通过应变片和热电偶来捕捉杆中间截面表层材料的相变演化,采用热电偶测量杆中间截面受拉侧的温度,分析了长细比和材料相变对杆件承载能力的影响。结果表明:加载和卸载阶段,两端夹支TiNi杆的载荷-应变曲线随着长细比的改变发生明显的变化,对于短杆,相变会提高其承载能力;对于长杆,其极限承载能力取决于长细比,相变的影响集中在后屈曲阶段;对于低长细比杆件,加载阶段温度持续升高,而高长细比构件,应变达到最大值时温度已开始下降,所有杆件在卸载结束时的温度均低于加载初始时刻。

关键词：相变载荷位移曲线屈曲形状记忆合金伪弹性

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基于碳夹点分析的中国能源结构优化研究

资源科学 2015年第2期37卷 291-298页

作者：梁琳琳卢启程云南财经大学国际工商学院昆明650221 宁波大学商学院宁波315221 云南财经大学商学院昆明650221

本文研究了碳排放目标下我国能源结构的优化问题。论文运用碳夹点方法识别能源消费瓶颈,并通过能源替代确定满足碳排放约束的清洁能源量,最后以我国政府承诺的2020年碳减排目标为例,基于对2020年我国能源消费及碳排放量的预测,对我国整... 详细信息

本文研究了碳排放目标下我国能源结构的优化问题。论文运用碳夹点方法识别能源消费瓶颈,并通过能源替代确定满足碳排放约束的清洁能源量,最后以我国政府承诺的2020年碳减排目标为例,基于对2020年我国能源消费及碳排放量的预测,对我国整体能源结构优化进行实证分析。研究结果表明,2020年我国预测碳排放量高于碳减排目标,在清洁能源达到2 466.8万TJ^3 496.2万TJ时,能够实现2020年比2005年单位GDP减排40%~45%的碳排放目标。研究发现,碳排放约束下能源结构优化必须在一定的激励和约束措施下才能实现,且关键在于降低高碳能源的比重。能源结构的优化需依据能源的碳排放因子,按照由低向高的顺序通过清洁能源对高碳能源的替代来实现。清洁能源消费比重的提升是实现2020年碳减排目标的关键。中国经济步入以中高速增长为标志的"新常态"将有利于2020年能源消费总量的控制以及清洁能源消费比重的增加。

关键词：碳排放目标能源结构优化碳夹点分析能源替代中国