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Policy Network-Based Dual-Agent Deep Reinforcement Learning for Multi-Resource Task Offloading in Multi-Access Edge Cloud Networks

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China Communications 2024年第4期21卷 53-73页

作者： Feng Chuan Zhang Xu han pengchao Ma Tianchun Gong Xiaoxue School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute of Intelligent Communication and Network Security Chongqing University of Posts and TelecommunicationsChongqing 400065China Key Laboratory of Big Data Intelligent Computing Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China

The Multi-access Edge Cloud(MEC) networks extend cloud computing services and capabilities to the edge of the networks. By bringing computation and storage capabilities closer to end-users and connected devices, MEC networks can support a wide range of applications. MEC networks can also leverage various types of resources, including computation resources, network resources, radio resources,and location-based resources, to provide multidimensional resources for intelligent applications in 5/***, tasks generated by users often consist of multiple subtasks that require different types of resources. It is a challenging problem to offload multiresource task requests to the edge cloud aiming at maximizing benefits due to the heterogeneity of resources provided by devices. To address this issue,we mathematically model the task requests with multiple subtasks. Then, the problem of task offloading of multi-resource task requests is proved to be NP-hard. Furthermore, we propose a novel Dual-Agent Deep Reinforcement Learning algorithm with Node First and Link features(NF_L_DA_DRL) based on the policy network, to optimize the benefits generated by offloading multi-resource task requests in MEC networks. Finally, simulation results show that the proposed algorithm can effectively improve the benefit of task offloading with higher resource utilization compared with baseline algorithms.

关键词： benefit maximization deep reinforcement learning multi-access edge cloud task offloading

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Directional Routing Algorithm for Deep Space Optical Network

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China Communications 2017年第1期14卷 158-168页

作者： Lei Guo Xiaorui Wang Yejun Liu pengchao han Yamin Xie Yuchen Tan Key Laboratory of Medical Image Computing of Northeastern University Ministry of Education School of Computer Science and Engineering Northeastern University Shenyang 110819 China School of Computer and Communication Engineering Zhengzhou University of Light Industry Zhengzhou 450002 China State Key Laboratory of Information Photonics and Optical Communications (BUPT) 100876 China

With the development of science, economy and society, the needs for research and exploration of deep space have entered a rapid and stable development stage. Deep Space Optical Network(DSON) is expected to become an important foundation and inevitable development trend of future deepspace communication. In this paper, we design a deep space node model which is capable of combining the space division multiplexing with frequency division multiplexing. Furthermore, we propose the directional flooding routing algorithm(DFRA) for DSON based on our node model. This scheme selectively forwards the data packets in the routing, so that the energy consumption can be reduced effectively because only a portion of nodes will participate the flooding routing. Simulation results show that, compared with traditional flooding routing algorithm(TFRA), the DFRA can avoid the non-directional and blind transmission. Therefore, the energy consumption in message routing will be reduced and the lifespan of DSON can also be prolonged effectively. Although the complexity of routing implementation is slightly increased compared with TFRA, the energy of nodes can be saved and the transmission rate is obviously improved in DFRA. Thus the overall performance of DSON can be significantly improved.

关键词： deep space optical network routing algorithm directional flooding routing algorithm traditional flooding routing algorithm

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激光熔凝车用304不锈钢组织及力学性能研究

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应用激光 2024年第5期44卷 21-27页

作者：杨自斌武鹏超韩加强信阳职业技术学院汽车与机电工程学院信阳河南464000 福州大学机械工程及自动化学院福建福州350116 上汽大众汽车有限公司上海201805

为提高车用304不锈钢的耐磨性,采用激光熔凝技术对车用304不锈钢表面进行强化。通过金相显微镜、显微硬度计、摩擦磨损试验机、扫描电镜及能谱仪分别对熔凝层宏观形貌、微观组织、显微硬度、磨痕形貌及磨损机理进行分析。结果表明,激光... 详细信息

为提高车用304不锈钢的耐磨性,采用激光熔凝技术对车用304不锈钢表面进行强化。通过金相显微镜、显微硬度计、摩擦磨损试验机、扫描电镜及能谱仪分别对熔凝层宏观形貌、微观组织、显微硬度、磨痕形貌及磨损机理进行分析。结果表明,激光熔凝后,熔凝层无气孔、裂纹等缺陷,组织均匀致密。激光熔凝急热急冷的特性,显著细化了熔凝层的显微组织,熔凝层主要由树枝晶和等轴晶组成。细晶强化是熔凝层硬度提升的主要原因,熔凝层的显微硬度约为281 HV,相较于304不锈钢基体提升了约50%。由于硬度的提升,熔凝层的摩擦因数和磨损率均有下降,分别为0.544和2.46×10^(-5)(N·m)。熔凝层磨损机理为磨粒磨损。激光熔凝可有效提升304不锈钢的硬度和耐磨性。

关键词：激光熔凝 304不锈钢硬度耐磨性

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OFDM无源光网络中多业务分层带宽分配算法

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通信学报 2018年第9期39卷 84-93页

作者：刘业君刘玉莹汉鹏超王继东郭磊东北大学计算机科学与工程学院智慧系统国际合作联合实验室辽宁沈阳110819

正交频分复用无源光网络(OFDM-PON,orthogonal frequency division multiplexing passive optical network)具有带宽容量大、资源分配灵活等优势,被公认为下一代光接入网的重要候选技术之一。目前,OFDM-PON系统结构的相关研究层出不穷,... 详细信息

正交频分复用无源光网络(OFDM-PON,orthogonal frequency division multiplexing passive optical network)具有带宽容量大、资源分配灵活等优势,被公认为下一代光接入网的重要候选技术之一。目前,OFDM-PON系统结构的相关研究层出不穷,然而这些研究大多专注于物理结构和信号传输技术,缺少与新型系统结构相适应的带宽分配算法。OFDM-PON中带宽分配涉及时域、频域、比特等多维资源的联合优化,是保证多业务接入和服务质量的关键技术。针对OFDM-PON的增强型系统结构,提出多业务分层带宽分配算法,以实现增强型OFDM-PON系统带宽资源的高效利用。仿真结果表明,相比传统OFDM-PON系统中无分层带宽分配算法,增强型OFDM-PON的分层带宽分配算法在带宽资源利用率和数据分组时延等性能方面具有明显优势。

关键词：正交频分复用无源光网络动态带宽分配分层带宽分配多业务传输

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镀镍石墨烯/钛复合材料界面力学行为的分子动力学研究

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精密成形工程 2024年第4期16卷 45-52页

作者：王锐韩秀丽康鹏超李婉莹武高辉哈尔滨工业大学材料科学与工程学院哈尔滨150000

目的研究拉伸载荷下镀镍石墨烯/钛复合材料界面的应力-应变行为。方法采用分子动力学模拟方法,建立了镀镍石墨烯/钛复合材料界面的单晶模型,研究了不同方向拉伸载荷下材料的力学行为。结果镀镍石墨烯复合材料的力学性能随着镀层厚度的... 详细信息

目的研究拉伸载荷下镀镍石墨烯/钛复合材料界面的应力-应变行为。方法采用分子动力学模拟方法,建立了镀镍石墨烯/钛复合材料界面的单晶模型,研究了不同方向拉伸载荷下材料的力学行为。结果镀镍石墨烯复合材料的力学性能随着镀层厚度的增大而提高,镀层镍可以作为位错源使复合材料的位错密度提高,镀层镍塑性变形的滞后使镀镍石墨烯/钛复合材料具有更高的塑性变形能力。结论材料的力学性能更多依赖于镀镍层数,随着镀层厚度的增大,镀镍石墨烯/钛复合材料表现出了更高的抗拉强度,但界面处的裂纹和空洞数量也有所增加,材料的延伸率有所下降。

关键词：镀镍石墨烯钛基复合材料分子动力学界面力学行为

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SIRT3激动剂厚朴酚通过抑制海马神经元铁死亡缓解小鼠术后认知功能障碍

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中国病理生理杂志 2024年第5期40卷 827-835页

作者：黄涛韩甜甜许倩倩张振胡鹏超丁旭东罗辉宇曾炼湖北医药学院附属襄阳市第一人民医院湖北武汉430000 华中科技大学同济医学院附属同济医院麻醉科湖北武汉430000

目的:探究沉默信息调节因子3(SIRT3)激动剂厚朴酚(HKL)在小鼠术后认知功能障碍(POCD)中的作用及其可能机制。方法:将10月龄雄性C57/BL6小鼠随机分成对照(Con)组、手术(Sur)组和Sur+HKL组(n=10)。Sur+HKL组小鼠给予HKL腹腔注射预处理7 d,... 详细信息

目的:探究沉默信息调节因子3(SIRT3)激动剂厚朴酚(HKL)在小鼠术后认知功能障碍(POCD)中的作用及其可能机制。方法:将10月龄雄性C57/BL6小鼠随机分成对照(Con)组、手术(Sur)组和Sur+HKL组(n=10)。Sur+HKL组小鼠给予HKL腹腔注射预处理7 d,Sur和Sur+HKL组小鼠均采用胫骨骨折切开复位内固定术的方法建立POCD模型。使用旷场实验、新物体识别实验、Morris水迷宫实验和Y迷宫实验来检测小鼠的认知功能;尼氏染色评价小鼠海马和皮层神经元形态、结构和活力;Western blot检测小鼠海马谷胱甘肽过氧化物酶4(GPX4)、溶质载体家族7成员11(SLA7A11)、酰基辅酶A合成酶长链家族成员4(ACSL4)、SIRT3和核因子E2相关因子2(NRF2)蛋白的表达;免疫荧光染色测定GPX4表达水平。结果:与Con组比较,Sur组和Sur+HKL组小鼠在旷场实验中移动的总距离和中央区域探索时间差异无统计学意义(P>0.05);新物体识别实验和Y迷宫实验结果显示,Sur组小鼠识别指数和轮替次数较Con组显著降低(P<0.01),侧臂封锁再通后,小鼠进入新臂的距离百分比和次数百分比显著下降(P<0.01);水迷宫训练时Sur组小鼠潜伏期较Con组下降缓慢,测试时Sur组小鼠潜伏期、目的象限穿越次数及穿越时间百分比均显著低于Con组(P<0.01);与Sur组比较,Sur+HKL组上述指标均显著升高(P<0.01)。尼氏染色结果显示,Sur组小鼠海马CA1区和内侧前额叶皮层的神经元染色较浅,尼氏染色阳性神经元数量显著下降(P<0.01);HKL治疗后神经元活力明显增强。Western blot结果显示,与Con组比较,Sur组SIRT3、GPX4、SLC7A11和NRF2蛋白表达水平显著降低(P<0.05),ACLS4蛋白表达水平显著升高(P<0.05);与Sur组比较,Sur+HKL组上述结果被逆转,差异有统计学意义(P<0.05)。海马神经元的免疫荧光染色与Western blot结果一致,Sur组海马区神经元中GPX4的表达水平显著下降,HKL显著升高神经元GPX4的表达水平(P<0.01)。结论:SIRT3激动剂HKL缓解小鼠POCD,其作用机制可能是抑制了海马神经元铁死亡。

关键词：厚朴酚术后认知功能障碍铁死亡沉默信息调节因子3

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Droplets deposition and harvest-aid efficacy for UAV application in arid cotton areas in Xinjiang,China

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 9-18页

作者： Guobin Wang Jiahui Wang pengchao Chen Xiaoqiang han Shengde Chen Yubin Lan School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049ShandongChina National Center for International Collaboration Research on Precision Agricultural Aviation Pesticides Spraying Technology(NPAAC) Ministry of Science and TechnologyCollege of Electronic EngineeringSouth China Agricultural UniversityGuangzhou 510642China College of Agricultural Shihezi UniversityShihezi 832000XinjiangChina Department of Biological and Agricultural Engineering Texas A&M UniversityCollege StationTX 77845

With the development of Unmanned Aerial Vehicle(UAV)sprayers,the application of low-volume spraying of harvest-aid and other agrochemicals to cotton using UAVs is becoming a new agronomic trend *** effect of spray volume and canopy density for UAV spraying is significant but was rarely *** this study,five representative spray volumes were explored to examine the effect of spray volume on deposition and harvest-aid efficacy for cotton using a UAV *** explore the effect of canopy density,similar tests were carried out in a field located nearby with a lower leaf area index(LAI).A conventional trailer boom sprayer was selected for *** spray volumes had a significant effect on defoliation,but had no significant effect on boll opening and fiber quality.A higher defoliation rate was achieved in the lower LAI *** total rate of defoliation using the UAV was inferior to the boom sprayer in the high LAI field for lower deposition and defoliation rate in the lower *** the deposition,defoliation rate,and working efficiency,a spray volume of 15.0 L/hm^(2) with an average droplet size of 150μm is recommended for UAV application.

关键词： UAV droplets deposition spray volume canopy density leaf area index defoliation boll opening rate

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高放废物处置坑小直径盲井掘进机预选刀具破岩性能对比分析

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世界核地质科学 2024年第4期41卷 792-804页

作者：王鹏超殷丽君龚秋明马洪素马函北京工业大学城市与工程安全减灾教育部重点实验室北京100124 核工业北京地质研究院北京100029 中国国家原子能机构高放废物地质处置创新中心北京100029

盲井掘进机是处置坑开挖的常用设备,刀具的合理设计与布置是其高效掘进的关键。北京工业大学TBM与盾构课题组针对北山高放废物处置坑小直径盲井掘进机预选了11英寸(279 mm)双排锥齿滚刀和双排镐齿滚刀两种刀型。本研究应用两种预选刀型... 详细信息

盲井掘进机是处置坑开挖的常用设备,刀具的合理设计与布置是其高效掘进的关键。北京工业大学TBM与盾构课题组针对北山高放废物处置坑小直径盲井掘进机预选了11英寸(279 mm)双排锥齿滚刀和双排镐齿滚刀两种刀型。本研究应用两种预选刀型对北山花岗岩试样进行线性切割破岩试验,对比分析两种刀型的滚刀力、破岩比能、岩片分布、振动特征和岩下损伤特性等指标。试验结果表明:锥齿滚刀在相同贯入度下的破岩法向力和振动强度小于镐齿滚刀,锥齿滚刀破岩效率整体上更高,并且锥齿滚刀破岩产生的贯通裂纹发育也更为显著。综合比较分析认为锥齿滚刀破岩性能更优,推荐采用预选的双排锥齿滚刀进行北山处置坑小直径盲井掘进机刀盘布置。本研究还可为盲井掘进机刀盘与推进系统设计及施工运行参数优化提供参考。

关键词：锥齿滚刀镐齿滚刀小直径盲井掘进机处置坑北山花岗岩

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Use of VA-ECMO successfully rescued a trauma patient with fat embolism syndrome complicated with acute heart failure and acute respiratory distress syndrome

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World Journal of Emergency Medicine 2023年第4期14卷 332-334页

作者： pengchao Guo Taiwen Rao Wen han Licai Liang Hongjue Ji Hong Liu Qin Lu Emergency Department the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China

Fat embolism syndrome(FES)is a fatal complication of long bone fractures and multiple *** FES can lead to potentially fatal respiratory failure in the form of rapidly developing acute respiratory distress syndrome(ARDS).Here,we report a case of venousarterial extracorporeal membrane oxygenation(VAECMO)treatment of a patient with near-fatal pulmonary fat emboli caused by severe trauma.

关键词： distress respiratory acute

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A creatinine-based model for predicting recurrent bleeding after modified percutaneous transhepatic variceal embolization in patients with cirrhosis

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Journal of Interventional Medicine 2022年第2期5卷 95-102页

作者： Kun Ji Xin Li hanlong Zhu Si Zhao pengchao Zhan Yang Shi Shuwen Ye Bingcan Xie Yuyuan Zhang Peng Yu Zhigang Ren Juan Ding Xinwei han Zhen Li Hepaobilary and Pancreatic Ientionod Treatment Center Divston of Heptbiliay and Pancreatic SurgenyThe Pirst fliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Deprtnent of Inteventional Radiology The First Aftlated Hospital of Zhengzhou UntversityZhengzhouHenan ProvinceChina Department of Gastroenterology and Hpatology Jinling HopitalMedical School of Nanjing UneversiyNanjing210002Jiangsu ProvinceChina Deparment of Gastroenterology filiated Drum Tower Hospitadl of Nanying University Medical SchooNajin 210008Jiangsu ProvinceChina Department of Infecious Diseases The Frst Afilated Hosital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Qualiy Conurol The Pirnt Afllated Hospital of Zhengzhou UnivesiyZhenghouHenarn ProwinceChina

Background:Patients who survive initial esophagogastric variceal bleeding(EVB)are at an increased risk of recurrent bleeding and death;however,a reliable predictive model is *** aimed to develop a model for rebleeding prediction in patients with EVB after modified percutaneous transhepatic variceal embolization(PTVE)with ***:A total of 122 patients with EVB who underwent PTVE from January 2015 to November 2020 were *** logistic analyses were conducted to determine independent risk factors for nomogram *** discrimination,calibration,and clinical utility of the nomogram were compared with the Model for End-stage Liver Disease score(MELD)and the Child–Pugh *** stratification was performed according to the ***:Rebleeding within 3 months of PTVE occurred in 32 patients(26.2%).Independent rebleeding indicators included prior history of endoscopic therapy,Child–Pugh score,partial splenic embolization,and creatinine *** nomogram incorporating these four predictors achieved excellent calibration and discriminatory abilities,with a concordance index of 0.85,which was confirmed to be 0.83 through bootstrapping *** nomogram demonstrated superior discrimination and clinical applicability than the MELD and Child–Pugh *** shown in the Kaplan–Meier curves,high-risk patients had a high probability of rebleeding(P<0.001).Conclusions:The creatinine-based nomogram had a superior ability to predict rebleeding after PTVE in patients with *** stratification may help identify high-risk patients and lead to the earlier implementation of aggressive treatments and formulation of intensive follow-up plans.

关键词： Esophagogastric varices Percutaneous transhepatic variceal embolization Nomogram Prediction

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