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A physical layer security scheme for full-duplex communication systems with residual self-interference and non-eavesdropping CSI

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Digital Communications and Networks 2021年第3期7卷 352-361页

作者： Weijia Lei Yang Zhou Xiuzhen Lin School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

We discuss the physical layer security scheme in the Full-Duplex(FD)MIMO point-to-point two-way communication system with residual self-interference,in which legitimate nodes send confidential information and null space Artificial Noise(AN)while receiving information.Because the Channel State Information(CSI)of the eavesdropper is unavailable,we optimize the covariance matrices of the information signal as well as the allocation of the antenna for transmitting and receiving to minimize the signal power consumption under the target rate constraint.As a result,the power of AN is maximized within the limit of total power,so the interception capability of the eavesdropper is suppressed as much as possible.Since self-interference cannot be completely eliminated,the optimization process of one legitimate node depends on the optimization result of the other.By substituting self-interference power in the secrecy rate formula with its average value,the joint optimization process at the two nodes is transformed into two separate and solvable optimization processes.Then,the Water-Filling Algorithm(WFA)and bisection algorithm are used to get the optimal covariance matrices of the signal.Furthermore,we derive the theoretical lower bound of ergodic achievable secrecy rate under rayleigh channels to evaluate the performance of the scheme.The simulation results show that the theoretical derivation is correct,and the actual achievable rate is very close to the target rate,which means that the approximation in the optimization is feasible.The results also show that secrecy transmission can be realized because a considerable secrecy rate can be achieved.

关键词： Physical layer security Full-duplex Self-interference Eavesdropping CSI Multi-antenna

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The distribution and evolution of surface fractures on pan-Antarctic ice shelves

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International Journal of Digital Earth 2023年第1期16卷 3295-3320页

作者： Ao Pang Qi Liang weijia Li lei Zheng Teng Li Xiao Cheng School of Geospatial Engineering and Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiPeople’s Republic of China Key Laboratory of Comprehensive Observation of Polar Environment Sun Yat-sen UniversityMinistry of EducationZhuhaiPeople’s Republic of China

Surface fractures have a great impact on ice shelf stability in Antarctica and can be considered precursors of ice shelf calving.However,our understanding of the spatial distribution and temporal evolution of surface fractures on the Antarctic ice shelf is limited.In this study,a ResUNet model was implemented on the Moderate Resolution Imaging Spectroradiometer(MODIS)-based Mosaic of Antarctica(MOA)to identify the spatial distribution of Antarctic ice shelf surface fractures in 2004,2009,and 2014.The accuracy of identification had an F1 value of 0.771.Our model identified 44744.59±2619.61 km^(2)of surface fractures in 2004,43737.15±2644.60 km^(2)in 2009,and 42978.67±2639.33 km^(2)in 2014.The reduction is primarily attributed to the variation in surface fractures within 20 km of the ice front,paratactically in the Amundsen and Wilkes sectors.Ice shelves in the Amundsen sector typically have a widespread distribution of surface fractures,with particularly high concentrations found in the Thwaites Ice Shelf,Crosson Ice Shelf and Getz Ice Shelf.The Brunt Ice Shelf also exhibits numerous surface fractures.This study provides comprehensive and detailed information about surface fractures on Antarctic ice shelves,carrying implications for evaluating ice shelf vulnerability.

关键词： Surface fractures Antarctic ice shelf ResUNet MOA

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Enhanced photoluminescence and stability of ZnSe microspheres/Cs4PbBr6 microcrystals/CsPbBr3 nanocrystals composites

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Chinese Chemical Letters 2020年第9期31卷 2499-2502页

作者： Chao Zhang Tingting Li lei Pu weijia Wen Xiangdong Luo Lijuan Zhao Materials Genome Institute Shanghai UniversityShanghai 200444China Jiangsu Key Laboratory of ASIC Design Nantong UniversityNantong 226019China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

A ternary complex combining dual-phase perovskites-Cs4PbBr6/CsPbBr3(DP-CPB) with ZnSe micropshere s(ZnSe-DP-CPB) was succes s fully prepared using supersaturated recrystallization technique at room temperature.It was showed that the DP-CPB composites were partially embedded in ZnSe microsphere composed with ZnSe NCs.The light absorption range of ZnSe-DP-CPB composites was extended from visible to near infrared light.Highly enhanced luminescence from ZnSe-DP-CPB composite was observed and the excitation power-dependent photoluminescence showed that the recombination involves excitons.The recombination lifetimes of the ternary composites increased compared with DP-CPB composite,indicating that the non-radiative combination was suppressed which maybe possibly due to the decrease of both bulk and surface defects,owing to the passivation of ZnSe,as well as the suitable band alignments of these three components.The ternary complex also showed improved stability of photoluminescence(PL),which opens a newavenue for enhancing the stability of PL and optoelectronic applications for semiconductor-perovskite composites.

关键词： Dual-phase perovskites Ternary complex Supersaturated recrystallization Photoluminescence Passivation Optoelectronic

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Thermo-Flow Performances for the Main-Auxiliary Integrated Natural Draft Dry Cooling System

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Journal of Thermal Science 2024年第3期33卷 1010-1025页

作者： ZHANG Zongyang HOU Yichen ZHOU Hanyu JIA He CHEN lei KONG Yanqiang WANG weijia YANG Lijun DU Xiaoze Key Laboratory of Power Station Energy Transfer Conversion and System of Ministry of Education School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

Recently,natural draft dry cooling system with the main-auxiliary integrated air-cooled heat exchangers in the up and lower layers,has drawn attention to the electric power industry.This research firstly develops two physical models for the integrated cooling system,namely Case A and Case B.In Case A,the main air-cooled heat exchanger is arranged in the upper layer and the auxiliary air-cooled heat exchanger arranged in the lower layer,while in Case B,the two heat exchanger systems are arranged in the opposite way.And then,directing at the engineering TMCR and TRL 1 working conditions,the unit-local-overall thermo-flow characteristics of Case A and Case B are obtained and compared by numerical simulation.The findings show that,for the auxiliary air-cooled exchanger,Case A has obviously higher cooling performances than Case B,with the difference varying from 5.46%to 7.55%.Whereas,for the main air-cooled exchanger,Case B shows the recovered cooling performances,with the difference changing from 1.15%to 2.99%.Case A is preferably recommended to the engineering application in consideration of more strict cooling demand of the auxiliary cooling system.Conclusively,this research will provide some theoretical guidelines for the design and construction of the main-auxiliary integrated natural draft dry cooling system.

关键词： integrated dry cooling system main air-cooled heat exchanger auxiliary air-cooled heat exchanger upper layer and lower layer thermo-flow performances

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能量收集多天线发送机的功率控制和天线选择

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西安电子科技大学学报 2022年第3期49卷 83-92页

作者：宁晓晗雷维嘉重庆邮电大学通信与信息工程学院重庆400065 重庆邮电大学移动通信技术重庆市重点实验室重庆400065

针对能量收集多输入单输出无线通信系统传输过程中的速率最大化问题,提出一种基于李雅普诺夫优化框架的在线功率控制和天线选择策略。系统中源节点为能量收集设备供电的多天线节点,且天线激活后的射频电路功耗不可忽略。激活天线数越多... 详细信息

针对能量收集多输入单输出无线通信系统传输过程中的速率最大化问题,提出一种基于李雅普诺夫优化框架的在线功率控制和天线选择策略。系统中源节点为能量收集设备供电的多天线节点,且天线激活后的射频电路功耗不可忽略。激活天线数越多,发送天线阵列增益越大,但电路功耗也越大,需要在二者间进行平衡。源节点应根据可用能量和信道状态来选择合适的发送天线和传输功率。由于能量到达和信道衰落是随机过程,该速率最大化问题是一个随机优化问题。由可充电电池的电量构造能量虚队列,而速率的负值作为惩罚项,再利用李雅普诺夫优化框架将功率控制与天线选择的优化问题转换为瞬时队列漂移加惩罚函数最小化问题。每时隙遍历电池电量支持的激活天线数,并优化发送功率,选取使漂移加惩罚最小的天线数和发送功率作为最优解。仿真结果表明,相比3种对比算法,算法能够获得明显更高的传输速率。所提算法仅依据当前的信道状态和电池电量状态做出决策,且计算复杂度低,是一种实用的算法。

关键词：通信技术能量收集功率控制天线选择李雅普诺夫框架

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Total suprarenal aortic occlusion with cardiac disease: a case series of three cases

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World Journal of Emergency Medicine 2024年第1期15卷 59-61页

作者： Yuanli lei Jiaozhen Chen Qin Chen Jiana Yin weijia Huang Wenxing Song Shouquan Chen Department of Emergency Medicine the First Affi liated Hospital of Wenzhou Medical UniversityWenzhou 325000China Department of Electrocardiogram Wenzhou People's HospitalWenzhou 325000China

Acute aortic occlusion(AAO)has been very rarely reported in the literature and is a potentially life-threatening emergency.[1-5]AAO mostly occurs in cardiac disease patients,[1-4,6,7]and leads to cardiac complications.[1,2,5,6]Suprarenal aortic occlusion(SAO)is a very rare type of AAO,and infrarenal aortic occlusion(IAO)accounts for 75.8%-97.8%.[1,3,5-7]SAO is different from IAO in some clinical manifestations,treatment strategies,and prognoses.[3,6-8]SAO with cardiac disease will make the condition more complex and could easily cause a delay in diagnosis and portend worse outcomes with amputation and mortality rates.[1,3,6]Early and fast diagnosis and positive revascularization treatment are necessary to prevent cases from becoming fatal.[1-3]Herein,we present a case series of SAO with cardiac disease.

关键词： cardiac occlusion diagnosis

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Glutathione-depleted cyclodextrin pseudo-polyrotaxane nanoparticles for anti-inflammatory oxaliplatin(Ⅳ) prodrug delivery and enhanced colorectal cancer therapy

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Chinese Chemical Letters 2024年第4期35卷 280-286页

作者： Wenjia Wang Xingyue He Xiaojie Wang Tiantian Zhao Osamu Muraoka Genzoh Tanabe weijia Xie Tianjiao Zhou lei Xing Qingri Jin Hulin Jiang State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China Faculty of Pharmacy Kinki University HigashiosakaOsaka 577-8502Japan State Key Laboratory of Natural Medicines(SKLNM)and Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjing 210009China School of Pharmacy Hangzhou Medical CollegeHangzhou 311399China College of Pharmacy Yanbian UniversityYanji 133002China

Oxaliplatin(Oxa) is the first-line chemotherapeutic drug for the treatment of colorectal cancer(CRC). However, long-term Oxa chemotherapy can induce inflammation and increase the levels of cyclooxygenase-2(COX-2) and prostaglandin E2(PGE2), which can promote tumor metastasis. Moreover,high glutathione(GSH) levels in CRC cells significantly reduce Oxa sensitivity and seriously restrict the clinical application of Oxa. Herein, an Oxa(Ⅳ) prodrug with anti-inflammatory properties(desmethyl naproxe, DN) and GSH-depleting cyclodextrin pseudo-polyrotaxane carriers were prepared and further self-assembled into micellar nanoparticles(designated DNPt@PPRI). The relesae of DN from DNPt@PPRI can reduce the level of PGE2 to inhibit inflammation and tumor metastasis by decreasing COX-2 protein,and also synergize with Oxa to inhibit tumor. More importantly, GSH depletion can reduce the detoxification of Oxa and further enhance chemotherapy-induced apoptosis. DNPt@PPRI have a good GSH depletion ability to enhance the sensitivity of Oxa, indicating a potential in the synergistic chemotherapy and chemo-sensitization of colorectal cancer.

关键词： Oxaliplatin Glutathione depletion Tetravalent platinum prodrug Synergistic therapy Colorectal cancer

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时间反转多用户系统中保密和速率优化的预处理滤波器设计

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电子与信息学报 2020年第5期42卷 1253-1260页

作者：雷维嘉杨苗苗重庆邮电大学通信与信息工程学院重庆400065

利用无线信道的特征通过物理层技术实现信息的安全传输是保密通信的一种方式。时间反转传输特有的时空聚焦特性使其具有天然的抗干扰和抗窃听能力,在单发射天线条件下也能获得较好的保密传输性能。该文研究两用户时间反转下行多址安全... 详细信息

利用无线信道的特征通过物理层技术实现信息的安全传输是保密通信的一种方式。时间反转传输特有的时空聚焦特性使其具有天然的抗干扰和抗窃听能力,在单发射天线条件下也能获得较好的保密传输性能。该文研究两用户时间反转下行多址安全传输系统中,发送滤波器脉冲响应的优化问题。根据互惠原则将两个发送滤波器的联合优化问题转换为各滤波器的独立优化问题,进一步将其转换为寻找最大特征值及其对应的特征向量的问题,并通过迭代算法进行求解。仿真结果表明,针对保密和速率优化预处理滤波器后,系统的可达保密速率明显优于采用常规时间反转预处理滤波器时的系统和直接传输系统。

关键词：物理层安全时间反转保密和速率预处理滤波器

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频域时间反转多用户系统的信干噪比和误比特率分析

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重庆邮电大学学报（自然科学版） 2023年第2期35卷 307-315页

作者：李丽雷维嘉重庆邮电大学通信与信息工程学院重庆400065 重庆邮电大学移动通信技术重庆市重点实验室重庆400065

为了更有效地将时间反转技术应用到正交频分复用系统中,推导了多天线频域时间反转预编码多用户系统的平均信干噪比和误比特率的表达式。通过推导信号功率均值的表达式和用户间干扰信号功率均值的近似表达式,得到用户的平均接收信干噪比... 详细信息

为了更有效地将时间反转技术应用到正交频分复用系统中,推导了多天线频域时间反转预编码多用户系统的平均信干噪比和误比特率的表达式。通过推导信号功率均值的表达式和用户间干扰信号功率均值的近似表达式,得到用户的平均接收信干噪比的近似表达式,进而得到二进制相移键控调制下的平均误比特率的一个下界和近似表达式。仿真结果表明,推导的平均信干噪比的近似值与仿真结果很接近,近似BER值与仿真得到的平均BER值较为接近;通过增大速率回退因子和天线数,可明显提高平均信干噪比,降低误比特率。

关键词：时间反转正交频分复用信干噪比误比特率

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Cell-type-specific genes associated with cortical structural abnormalities in pediatric bipolar disorder

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Psychoradiology 2022年第2期2卷 56-65页

作者： Wenkun lei Qian Xiao Chun Wang weijia Gao Yiwen Xiao Yingliang Dai Guangming Lu Linyan Su Yuan Zhong School of Psychology Nanjing Normal UniversityNanjingJiangsu 210097China Nanjing Normal University Jiangsu Key Laboratory of Mental Health and Cognitive ScienceNanjingJiangsu 210097China The Mental Health Centre of Xiangya Hospital Central South UniversityChangshaHunan 410008China The Department of Psychiatry Nanjing Brain Hospital Affiliated to Nanjing Medical UniversityNanjingJiangsu 210029China The Children’s Hospital affiliated to the Medical College of Zhejiang University HangzhouZhejiang 310003China The Department of Medical Imaging Jinling HospitalNanjing University School of MedicineNanjingJiangsu 210002China The Second Xiangya Hospital of Central South University ChangshaHunan 410008China

Background Pediatric bipolar disorder(PBD)has been proven to be related to abnormal brain structural connectivity,but how the abnormalities in PBD correlate with gene expression is debated.Objective This study aims at identification of cell-type-specific gene modules based on cortical structural differences in PBD.Methods Morphometric similarity networks(MSN)were computed as a marker of interareal cortical connectivity based on MRI data from 102 participants(59 patients and 43 controls).Partial least squares(PLS)regression was used to calculate MSN differences related to transcriptomic data in AHBA.The biological processes and cortical cell types associated with this gene expression profile were determined by gene enrichment tools.Results MSN analysis results demonstrated differences of cortical structure between individuals diagnosed with PBD and healthy control participants.MSN differences were spatially correlated with the PBD-related weighted genes.The weighted genes were enriched for“trans-synaptic signaling”and“regulation of ion transport”,and showed significant specific expression in excitatory and inhibitory neurons.Conclusions This study identified the genes that contributed to structural network aberrations in PBD.It was found that transcriptional changes of excitatory and inhibitory neurons might be associated with abnormal brain structural connectivity in PBD.

关键词： morphometric similarity Allen Human Brain Atlas pediatric bipolar disorder cell type

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