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Generation and characterization of orthogonal FH sequences for the cognitive network

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Science China(Information Sciences) 2015年第2期58卷 140-150页

作者： GUAN Lei LI Zan SI JiangBo huang yangchao State Key Laboratory of Integrated Services Networks Xidian University

The existing orthogonal frequency hopping(FH) sequence cannot support the high throughput and high spectrum efficient cognitive FH(CFH) network due to its small family size, high computational complexity and short period. To overcome these disadvantages, this paper investigates the generation of the orthogonal FH sequence and analyzes its multiple accessibility performance based on the CFH frequency division multipleaccess(FDMA) network model. By the random mapping and cyclical shift replacement(CSR) scheme, a large family size of orthogonal FH sequence with dynamic frequency slot number is generated. In this case, the external interference could be eliminated by avoiding the interfered frequencies, and blocking mutual interference incurred for the packet by the orthogonal frequencies. Moreover, the theoretical relationships of the throughput and transmission delay with respect to the user number and the packet arrival rate are given, which shows that our proposed orthogonal FH sequence could support high throughput and short packet transmission delay in CFH-FDMA network. The simulation results validate our theoretical analysis of the CFH-FDMA network performance, and show that our proposed sequence outperforms the widely used no hit zone FH sequences in terms of uniformity, randomness, Hamming correlation, complexity and sensitivity, etc.

关键词： cognitive frequency hopping orthogonal frequency hopping sequence frequency hopping network frequency division multiple access throughput

无人机群辅助边缘计算系统的任务卸载和资源分配联合优化

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系统工程与电子技术 2024年第2期46卷 751-760页

作者：刘世豪黄仰超胡航司江勃韩蕙竹安琪空军工程大学信息与导航学院陕西西安710077 西安电子科技大学综合业务网理论及关键技术国家重点实验室陕西西安710071

为提升无人机群辅助边缘计算系统在负载不均衡场景下的性能,构建了一种新的无人机群边缘计算系统,利用无人机之间卸载数据来提高计算资源的利用率,通过联合优化多架无人机的卸载方案、部署和资源分配,使得系统的时延和能耗加权和最小。... 详细信息

为提升无人机群辅助边缘计算系统在负载不均衡场景下的性能,构建了一种新的无人机群边缘计算系统,利用无人机之间卸载数据来提高计算资源的利用率,通过联合优化多架无人机的卸载方案、部署和资源分配,使得系统的时延和能耗加权和最小。该问题高度非凸,为此提出一种高效的双层优化算法——启发最优评价算法,上层使用粒子群算法优化无人机位置,下层在确定位置的情况下使用块坐标下降算法优化无人机的数据卸载和资源分配。仿真结果表明,所提方案可有效降低系统成本,与基准策略相比优势明显。

关键词：边缘计算无人机群任务卸载资源分配位置优化

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MaturePred:Efficient Identification of MicroRNAs within Novel Plant Pre-miRNAs

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MaturePred:Efficient Identification of MicroRNAs within Nove...

多无人机辅助的NOMA中继系统总通信速率优化

第五届全国生物信息学与系统生物学学术大会暨国际生物信息学前沿研讨会高通量时代的生物信息学与系统生物学

作者： Ping Xuan Maozu Guo yangchao huang Department of Computer Science and Engineering Harbin Institute of Technology School of Computer Science and Technology Heilongjiang University

Background:MicroRNAs(miRNAs) are a set of short(19～24nt) non-coding RNAs that play significant roles as posttranscriptional regulators in animals and *** ab initio prediction methods show excellent performance for discovering new *** most of these methods can distinguish real pre-miRNAs from pseudo pre-miRNAs,few can predict the positions of *** the existing methods that can also predict the miRNA positions,most of them are designed for mammalian miRNAs,including human and *** of methods can predict the positions of plant *** prediction of the miRNA positions remains a challenge,especially for plant *** motivates us to develop MaturePred,a machine learning method based on support vector machine,to predict the positions of plant miRNAs for the new plant pre-miRNA candidates. Methods:A miRNA:miRNA* duplex is regarded as a whole to capture the binding characteristics of *** extract the position-specific features,the energy related features,the structure related features,and stability related features from real/pseudo miRNA:miRNA* duplexes.A set of informative features are selected to improve the prediction ***-stage sample selection algorithm is proposed to combat the serious imbalance problem between real and pseudo miRNA:miRNA* *** prediction method,MaturePred,can accurately predict plant miRNAs and achieve higher prediction accuracy compared with the existing ***,we trained a prediction model with animal data to predict animal *** model also achieves higher prediction *** further confirms the efficiency of our miRNA prediction method. Conclusions:The superior performance of the proposed prediction model can be attributed to the extracted features of plant miRNAs and miRNA*s,the selected training dataset,and the carefully selected *** web service of MaturePred,the training datasets,the testing datasets,and the selected features are freely availab

关键词： mature miRNA feature selection sample selection position prediction

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华中科技大学学报（自然科学版） 2023年第11期51卷 105-113页

作者：黄仰超安琪胡航潘钰空军工程大学信息与导航学院陕西西安710077 中国人民解放军93886部队新疆乌鲁木齐830000 国防科技大学电子对抗学院安徽合肥230037

为解决无线通信中的频谱资源稀缺问题,提出一种多无人机(UAV)辅助的非正交多址(NOMA)接入中继系统.以优化系统总通信速率为目标,综合考虑信息因果约束、无人机发射功率约束与最大服务能力约束,构建了用户分组、无人机轨迹规划与功率分... 详细信息

为解决无线通信中的频谱资源稀缺问题,提出一种多无人机(UAV)辅助的非正交多址(NOMA)接入中继系统.以优化系统总通信速率为目标,综合考虑信息因果约束、无人机发射功率约束与最大服务能力约束,构建了用户分组、无人机轨迹规划与功率分配的联合优化问题.为解决这一高度耦合的非线性混合整数规划问题,提出一种两步优化策略.基于图论提出最大权匹配下的用户分组算法,根据分组结果,通过引入Sigmoid函数和辅助变量法,将功率分配和轨迹规划问题分别转化为几何规划与凸规划问题求解.仿真结果表明:所提出的两步优化算法能够有效提升系统的总通信速率.

关键词：无人机移动中继非正交多址用户分组轨迹规划

基于FRFT的多分量LFM信号检测与参数估计方法

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北京航空航天大学学报 2020年第6期46卷 1221-1228页

作者：宋耀辉黄仰超张衡阳秦智康高维廷空军工程大学信息与导航学院西安710077

针对传统方法搜寻效率低的问题,采取瞄准搜寻策略,提出一种快速精确地检测和估计多分量线性调频(LFM)信号参数的方法。推导出LFM信号的分数阶长度和旋转角度间的近似关系;利用分数阶幅度随旋转角度变化规律,提出一种高效搜寻最优旋转角... 详细信息

针对传统方法搜寻效率低的问题,采取瞄准搜寻策略,提出一种快速精确地检测和估计多分量线性调频(LFM)信号参数的方法。推导出LFM信号的分数阶长度和旋转角度间的近似关系;利用分数阶幅度随旋转角度变化规律,提出一种高效搜寻最优旋转角度的算法,分析得出该算法的计算量较小,相比于传统算法具有较大优势。在低信噪比情况下,进行两次S-G滤波可显著提高检测概率。仿真结果表明,所提方法在低信噪比和存在分量间信号干扰的情况下,能可靠检测和精确估计多分量LFM信号参数。

关键词：分数阶傅里叶变换(FRFT) 线性调频(LFM)信号瞄准搜寻 S-G滤波参数估计

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联合干扰功率限制下的认知中继网络性能分析

空军工程大学学报（自然科学版） 2016年第5期17卷 76-82页

作者：黄仰超褚鹏朱锐孟庆微西安电子科技大学综合业务网国家重点实验室西安710071 空军工程大学信息与导航学院西安710077 空军工程大学科研部西安710051

频谱共享的Underlay认知中继网络中,为了保证主用户的可靠通信,要求次用户网络中源节点及中继节点的发射功率必须满足主用户接收端干扰功率的限制。基于主用户峰值干扰功率和平均干扰功率的联合限制,分析了中继节点采用选择协作解码转... 详细信息

频谱共享的Underlay认知中继网络中,为了保证主用户的可靠通信,要求次用户网络中源节点及中继节点的发射功率必须满足主用户接收端干扰功率的限制。基于主用户峰值干扰功率和平均干扰功率的联合限制,分析了中继节点采用选择协作解码转发协议时潜伏式频谱共享认知中继网络的性能。值得一提的是,考虑中继传输中由主用户接收端干扰功率限制引起的第1跳链路信噪比之间的相关性,推导了瑞利衰落环境下次用户中断概率和信道容量准确的闭合表达式。仿真结论显示,次用户中断概率与信道容量的解析曲线与仿真结果一致,系统性能因频谱共享的认知网络中次用户源节点与主用户接收机链路之间的相关性而有所下降,中断概率约有2dB的性能提升。

关键词：认知中继网络频谱共享瑞利衰落中断概率信道容量

A thermodynamic perspective on electrode poisoning in solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1449-1455页

作者： Kevin huang Department of Mechanical Engineering University of South CarolinaColumbiaUSA

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell(SOFC)technology is the insuf-ficient stack lifespan caused by a variety of degradation mechanisms,which are associated with cell components and chemical *** components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions,whereas the latter regards impurities in feedstocks of oxidant(air)and reductant(fuel).This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in *** discussion focuses on using thermodynamic ana-lysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr,CO_(2),H_(2)O,and SO_(2) and in the anode by species such as S(or H_(2)S),SiO_(2),and P_(2)(or PH_(3)).The author hopes the presented fundamental insights can provide a theoretical foundation for search-ing for better technical solutions to address the critical degradation challenges.

关键词： impurities air fuel reaction activity

双通道时间交织ADC采样系统的频域纠正补偿

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电讯技术 2016年第4期56卷 408-411页

作者：黄仰超朱锐蒋磊孟庆微空军工程大学信息与导航学院西安710077

针对双通道时间交织模数转换器(ADC)采样系统中的通道间失配问题,提出了一种新的频域纠正补偿算法,即利用单次测量得到的不同频率处的固定补偿系数来实现时间交织ADC频响的部分补偿,并从理论和实验上分别进行了推导和可行性验证。实验... 详细信息

针对双通道时间交织模数转换器(ADC)采样系统中的通道间失配问题,提出了一种新的频域纠正补偿算法,即利用单次测量得到的不同频率处的固定补偿系数来实现时间交织ADC频响的部分补偿,并从理论和实验上分别进行了推导和可行性验证。实验结果表明:在双通道12比特2 Gsample/s时间交织ADC采样系统下,650 MHz带宽范围内的无杂散动态范围(SFDR)可以提高到40 d B。

关键词：时间交织ADC 信号采样通道间失配干扰抑制频响补偿

Fast Blood Oxygenation through Hemocompatible Asymmetric Polymer of Intrinsic Microporosity Membranes

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Research 2024年第1期2023卷 261-270页

作者： Xinxi huang Junping huang Pengcheng Su Wanbin Li Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China

Membrane technology has attracted considerable attention for chemical and medical applications,among *** organs play important roles in medical science.A membrane oxygenator,also known as artificial lung,can replenish O_(2) and remove CO_(2) of blood to maintain the metabolism of patients with cardiopulmonary ***,the membrane,a key component,is subjected to inferior gas transport property,leakage propensity,and insufficient *** this study,we report efficient blood oxygenation by using an asymmetric nanoporous membrane that is fabricated using the classic nonsolvent-induced phase separation method for polymer of intrinsic *** intrinsic superhydrophobic nanopores and asymmetric configuration endow the membrane with water impermeability and gas ultrapermeability,up to 3,500 and 1,100 gas permeation units for CO_(2) and O_(2),***,the rational hydrophobic–hydrophilic nature,electronegativity,and smoothness of the surface enable the substantially restricted protein adsorption,platelet adhesion and activation,hemolysis,and thrombosis for the ***,during blood oxygenation,the asymmetric nanoporous membrane shows no thrombus formation and plasma leakage and exhibits fast O_(2) and CO_(2) transport processes with exchange rates of 20 to 60 and 100 to 350 ml m^(−2) min^(−1),respectively,which are 2 to 6 times higher than those of conventional *** concepts reported here offer an alternative route to fabricate high-performance membranes and expand the possibilities of nanoporous materials for membrane-based artificial organs.

关键词： porosity asymmetric Oxygen