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Achieving the capacity of half-duplex degraded relay channels using polar coding

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Chinese Journal of Aeronautics 2014年第3期27卷 584-592页

作者： duo bin Wang Zhenyong Gu Xuemai Guo Qing School of Electronics and Information Engineering Harbin Institute of Technology

In this paper, a novel transmission protocol based on polar coding is proposed for the half-duplex degraded relay channel. In the proposed protocol, referred to as the partial message relaying, the relay only needs to forward a part of the decoded source message that the destination needs according to the exquisite nested structure of polar codes. Theoretically, it is proved that the scheme can achieve the capacity of the half-duplex relay channel under the decode-and-forward （DF） cooperation strategy while enjoying low encoding/decoding complexity. Practically, in order to minimize the global transmission power, the optimization of the power allocation is performed between the source and the relay by using information theoretic tools. Furthermore, a joint iterative soft parallel interference cancellation receiver structure is developed to suit to the proposed scheme. Simulation results show that the proposed scheme outperforms the conventional scheme designed by low-density parity-check （LDPC） codes.

关键词： Channel capacity Decode-and-forward:Half-duplex Iterative decoding Polar coding Relay channel

Joint Trajectory and Power Optimization for Securing UAV Communications Against Active Eavesdropping

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China Communications 2021年第1期18卷 88-99页

作者： bin duo Junsong Luo Yilian Li Hao Hu Zibin Wang College of Information Science and Technology Chengdu University of TechnologyChengdu 610059China National Key Laboratory of Science and Technology on Information System Security Beijing 100093China

Due to both of jamming and eavesdropping,active eavesdroppers can induce more serious security threats to unmanned aerial vehicle(UAV)-enabled *** paper considers a secure UAV communication system including both the downlink(DL)and uplink(UL)transmissions,where the confidential information is transmitted between a UAV and a ground node in the presence of an active *** aim to maximize the average secrecy rates of the DL and UL communications,respectively,by jointly optimizing the UAV trajectory and the UAV/ground node’s transmit power control over a given flight *** to the non-convexity of the formulated problems,it is difficult to obtain globally optimal ***,we propose efficient iterative algorithms to obtain high-quality suboptimal solutions by applying the block coordinate descent and successive convex optimization *** results show that the joint optimization algorithms can effectively improve the secrecy rate performance for both the DL and UL communications,as compared with other baseline *** proposed schemes can be considered as special cases of UAV-assisted non-orthogonal multiple access(NOMA)networks.

关键词： UAV communications active eavesdropping physical-layer security secrecy rate maximization power control trajectory design

Energy Efficiency Maximization for Cooperative NOMA with Hardware Impairments

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China Communications 2024年第12期21卷 80-91页

作者： Wang Zhengqiang Chang Ruifei Wan Xiaoyu Fan Zifu duo bin School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China College of Computer Science and Cyber Security Chengdu University of TechnologyChengdu 610059China

The massive connectivity and limited energy pose significant challenges to deploy the enormous devices in energy-efficient and environmentally friendly in the Internet of Things(IoT).Motivated by these challenges,this paper investigates the energy efficiency(EE)maximization problem for downlink cooperative non-orthogonal multiple access(C-NOMA)systems with hardware impairments(HIs).The base station(BS)communicates with several users via a half-duplex(HD)amplified-and-forward(AF)***,we formulate the EE maximization problem of the system under HIs by jointly optimizing transmit power and power allocated coefficient(PAC)at BS,and transmit power at the *** original EE maximization problem is a non-convex problem,which is challenging to give the optimal solution ***,we use fractional programming to convert the EE maximization problem as a series of subtraction form ***,variable substitution and block coordinate descent(BCD)method are used to handle the ***,a resource allocation algorithm is proposed to maximize the EE of the ***,simulation results show that the proposed algorithm outperforms the downlink cooperative orthogonal multiple access(C-OMA)scheme.

关键词： block coordinate descent cooperative non-orthogonal multiple access energy efficiency hardware impairments resource allocation

Intracranial hypertension as the primary symptom of malignant melanoma:A case report

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World Journal of Clinical Cases 2024年第21期12卷 4836-4841页

作者： Hai-Ting Xie Ding-Hao An duo-bin Wu Department of Neurology Southern Medical UniversityGuangzhou 510282Guangdong ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeNanjing 210008Jiangsu ProvinceChina Department of Neurology Zhujiang Hospital of Southern Medical UniversityGuangzhou 510282Guangdong ProvinceChina

BACKGROUND The etiological diagnosis of intracranial hypertension is quite complicated but important in clinical *** common causes are craniocerebral injury,intracranial space-occupying lesion,subarachnoid hemorrhage,and *** a patient presents with intracranial hypertension,the common causes are to be considered first so that other causes would be *** the morbidity lower than 9%,neuromelanin is very *** symp-toms include nerve damage symptoms,epilepsy,psychiatric symptoms,and cognitive *** SUMMARY We present a patient with melanoma which manifested with isolated intracranial hypertension without any other neurological signs.A 22-year-old male had repeated nausea and vomiting for 2 mo with Babinski sign(+)on both sides,nuchal rigidity,and subarachnoid *** had been diagnosed with melanoma and was given surgery and whole-brain ***,the patient died 2 mo *** Malignant melanoma should be taken into consideration in the differential diagnosis of intracranial hypertension.

关键词： Intracranial hypertension Diagnosis Melanoma Neuromelanin Case report

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低复杂度串行级联LDGM码构造方案

哈尔滨工业大学学报 2013年第5期45卷 25-29页

作者：多滨王振永顾学迈哈尔滨工业大学通信技术研究所哈尔滨150080

针对LDGM码的稀疏矩阵构造复杂度较高的问题,提出了一种具有低复杂度的LDGM码随机稀疏矩阵构造算法,该算法既降低了编码的复杂度又保证了良好的性能.同时,针对LDGM码存在明显的错误平层的问题,引入了串行级联结构,并提出了一种改进的SCL... 详细信息

针对LDGM码的稀疏矩阵构造复杂度较高的问题,提出了一种具有低复杂度的LDGM码随机稀疏矩阵构造算法,该算法既降低了编码的复杂度又保证了良好的性能.同时,针对LDGM码存在明显的错误平层的问题,引入了串行级联结构,并提出了一种改进的SCLDGM码译码算法,该算法将内译码器输出的错误信息看作是BEC信道的删除信息,利用该先验信息初始化外译码器的输入,从而进一步提高BER性能.通过对SCLDGM码编码系统模型的仿真,得到近优的内外编码速率组合和近优的内外码码重.仿真结果表明,本文提出的算法在保证低复杂度的前提下,可以获得良好的BER性能,并有效的降低了LDGM码错误平层.

关键词：信道编码 LDGM码 SCLDGM码稀疏矩阵低复杂度

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玻璃化转变对食品稳定性的影响

食品科学 2007年第12期28卷 539-546页

作者：赵学伟毛多斌郑州轻工业学院食品与生物工程学院河南郑州450002

本文首先简要介绍玻璃化转变对黏度、扩散和反应速率的影响,而后从物理稳定性、化学稳定性和生物学稳定性三个方面详细论述了玻璃化转变对食品稳定性的影响。在玻璃化转变温度附近温度降低使黏度增大,但小分子物质的扩散系数不再进一步... 详细信息

本文首先简要介绍玻璃化转变对黏度、扩散和反应速率的影响,而后从物理稳定性、化学稳定性和生物学稳定性三个方面详细论述了玻璃化转变对食品稳定性的影响。在玻璃化转变温度附近温度降低使黏度增大,但小分子物质的扩散系数不再进一步减小。食品可能因发生玻璃化转变而丧失稳定性,但玻璃化转变并不能成为衡量食品稳定性的唯一标准,发生玻璃化转变也不意味着食品稳定性立即丧失。根据玻璃化转变可以较好地预测食品的物理稳定性,而难以有效预测食品的化学和生物学稳定性。

关键词：玻璃化转变食品稳定性 WLF方程

近香农容量限的低复杂度Polar-LDGM码构造方案

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高技术通讯 2013年第6期23卷 564-570页

作者：多滨王振永顾学迈哈尔滨工业大学通信技术研究所哈尔滨150080

针对Polar码性能收敛速度慢和低密度生成矩阵(LDGM)码存在高错误平层的问题,在保持这两种码的低编码复杂度和低译码复杂度不变的前提下,提出了一种将Polar码作为外码,LDGM码作为内码的串行级联Polar-LDGM编译码设计方案,使之可以接近二... 详细信息

针对Polar码性能收敛速度慢和低密度生成矩阵(LDGM)码存在高错误平层的问题,在保持这两种码的低编码复杂度和低译码复杂度不变的前提下,提出了一种将Polar码作为外码,LDGM码作为内码的串行级联Polar-LDGM编译码设计方案,使之可以接近二进制输入加性高斯白噪声(BI-AWGN)信道香农容量。通过对Polar-LDGM编译码系统模型的仿真,得到了近优的内外码编码速率组合与近优的内码码重。仿真结果表明,上述方案在保证低复杂度的前提下,可以获得良好的比特错误率(BER)性能,并可以有效地降低LDGM码错误平层。

关键词：信道编码 Polar码低密度生成矩阵(LDGM)码香农限低复杂度

4-氨基-N-[3-(2-羟乙基)砜基]苯基苯甲酰胺的合成新工艺

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精细化工 2000年第7期17卷 404-406页

作者：毛多斌杨贯羽鲍改玲郑州轻工业学院食品工程系河南郑州450002 郑州大学化学化工学院河南郑州450052

以 3 ( 2 羟乙基砜基 )苯胺和对硝基苯甲酰氯为原料经酰化和催化氢化两步反应合成了 4 氨基 N [3 ( 2 羟乙基 )砜基 ]苯基苯甲酰胺 ,两步收率分别为 90 3%和 95 6%,总收率为 86.3%。在采用RanneyNi为催化剂和氢压为 0 2 4MP... 详细信息

以 3 ( 2 羟乙基砜基 )苯胺和对硝基苯甲酰氯为原料经酰化和催化氢化两步反应合成了 4 氨基 N [3 ( 2 羟乙基 )砜基 ]苯基苯甲酰胺 ,两步收率分别为 90 3%和 95 6%,总收率为 86.3%。在采用RanneyNi为催化剂和氢压为 0 2 4MPa的情况下 ,实验验证最佳的催化氢化反应条件为 :溶剂为甲醇 ,催化剂量为 30 %(催化剂与硝基物的质量比 ) ,反应温度为 50～ 60℃。产品经TLC、IR、1HNMR和MS确证。

关键词：氨基砜基苯基苯甲酰胺活性染料中间体工艺

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流体管网最不利环路的模糊分析

辽宁工程技术大学学报（自然科学版） 2007年第1期26卷 77-80页

作者：孙多斌王树刚解茂昭大连理工大学能源动力学院

为了解决在流体管网的计算和分析中遇到的问题,借助模糊数学理论,引入模糊相对阻抗的概念,探讨了模糊最不利环路的算法及其决策方法。为解决含有不确定性输入参数的管网最不利环路分析提供了一条简捷而有效的途径。最后通过实例分析,给... 详细信息

为了解决在流体管网的计算和分析中遇到的问题,借助模糊数学理论,引入模糊相对阻抗的概念,探讨了模糊最不利环路的算法及其决策方法。为解决含有不确定性输入参数的管网最不利环路分析提供了一条简捷而有效的途径。最后通过实例分析,给出了模糊最不利环路的隶属函数和总压降的决策方法。

关键词：管网最不利环路模糊分析模糊阻抗