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China Communications 2012年第6期9卷 28-35页

作者： Liu Hongquan gu yuantao Department of Electronic Engineering Tsinghua University Beijing 100084 P. R. China Research Institute of Air Force Armament Beijing 100076 P. R. China

A new approach, named TCP-I2NC, is proposed to improve the interaction between network coding and TCP and to maximize the network utility in interference-free multi-radio multi-channel wireless mesh networks. It is grounded on a Network Utility Maxmization (NUM) formulation which can be decomposed into a rate control problem and a packet scheduling problem. The solutions to these two problems perform resource allocation among different flows. Simulations demonstrate that TCP-I2NC results in a significant throughput gain and a small delay jitter. Network resource is fairly allocated via the solution to the NUM problem and the whole system also runs stably. Moreover, TCP-I2NC is compatible with traditional TCP variants.

关键词： network utility maximization net-work coding wireless mesh network TCP

Microstructure Evolution of Organic Matter and Clay Minerals in Shales with Increasing Thermal Maturity

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 280-289页

作者： gu yuantao LI Xiaoxia YANG Shuguang WAN Quan School of Resource and Environment Henan University of EngineeringZhengzhou 451191China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China

As the two important components of shale, organic matter(OM) and clay minerals are usually thought to strongly influence the hydrocarbon generation, enrichment and exploitation. The evolution process of OM and clay minerals as well as their interrelationship over a wide range of thermal maturities are not completely clear. Taking Yanchang(T3y), Longmaxi(S1l) and Niutitang(?1n) shales as examples, we have studied the microstructure characteristics of OM and clay minerals in shales with different thermal maturities. The effects of clay minerals and OM on pores were reinforced through sedimentation experiments. Using a combination of field emission scanning electron microscopy(FESEM) and low-pressure N2 adsorption, we investigated the microstructure differences among the three shales. The results showed that both OM and clay minerals have strong effects on pores, and small mesopore(2–20 nm) is the dominant pore component for all three samples. However, the differences between the three samples are embodied in the distribution of pore size and the location. For the T3y shale, clay minerals are loosely arranged and develop large amounts of pores, and fine OM grains often fill in intergranular minerals or fractures. Widespread OM pores distribute irregularly in S1l shale, and most of the pores are elliptical and nondirectional. The ?1n shale is characterized by the preferred orientational OM-clay aggregates, and lots of pores in the composites are in the mesopore range, suggesting that over maturity lead to the collapse and compaction of pores under huge pressure of strata. The results of the current research imply that with increasing thermal maturity, OM pores are absent at low maturity(T3y), are maximized at high maturity(S1l) and are destroyed or compacted at over-mature stage(?1n). Meanwhile, clay minerals have gone through mineral transformation and orientational evolution. The interaction of the two processes makes a significant difference to the microstructure evo

关键词： organic matter clay minerals OM-clay composites microstructure evolution thermal maturity

Performance Enhancement and Utility Maximization for TCP in Wireless Mesh Networks

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China Communications 2012年第4期9卷 35-44页

作者： Liu Hongquan Chen Jiong Song Siming gu yuantao Department of Electronic Engineering Tsinghua University Beijing 100084 P. R. China Research Institute of Air Force Armament Beijing 100076 P. R. China Department of Electronic Engineering University of Califomia Los Angeles Los Angeles 1002388 USA

In Wireless Mesh Networks (WMNs),the performance of conventional TCP significantly deteriorates due to the unreliable wireless *** enhance TCP performance in WMNs,TCP/LT is proposed in this *** introduces fountain codes into packet reorganization in the protocol stack of mesh gateways and mesh ***,it is compatible with conventional *** as a Performance Enhancement Proxies (PEP),a mesh gateway buffers TCP packets into several *** simultaneously processes them by using fountain encoders and then sends them to mesh *** from the improvement of the throughput of a unitary TCP flow,the entire network utility maximization can also be ensured by adjusting the scale of coding blocks for each TCP flow *** show that TCP/LT presents high throughput gains over single TCP in lossy links of WMNs while preserving the fairness for multiple *** losses increase,the transmission delay of TCP/LT experiences a slow linear growth in contrast to the exponential growth of TCP.

关键词： TCP TCP/LT fountain codes wireless mesh networks network utility maximization

The effects of clay minerals and organic matter on nanoscale pores in Lower Paleozoic shale gas reservoirs, guizhou, China

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Acta Geochimica 2018年第6期37卷 791-804页

作者： yuantao gu Quan Wan Wenbin Yu Xiaoxia Li Zhongbin Yu State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences School of Resource and Environment Henan University of Engineering

In organic-rich gas shales, clay minerals and organic matter(OM) have significant influences on the origin, preservation, and production of shale gas. Because of the substantial role of nanoscale pores in the generation,storage, and seepage of shale gas, we examined the effects of clay minerals and OM on nanoscale pore distribution characteristics in Lower Paleozoic shale gas *** the Niutitang and Longmaxi shales as examples, we determined the effects of clay minerals and OM on pores through sedimentation experiments. Field emission–scanning electron microscopy combined with low-pressure N2 adsorption of the samples before and after sedimentation showed significant differences in pore location and pore size distribution between the Niutitang and Longmaxi shales. Nanoscale pores mostly existed in OM in the Longmaxi shale and in clay minerals or OM–clay composites in the Niutitang shale. The distribution differences were attributed largely to variability in thermal evolution and tectonic development and might account for the difference in gas-bearing capacity between the Niutitang and Longmaxi reservoirs. In the nanoscale range, mesopores accounted for 61–76% of total nanoscale pore *** developed nanoscale pores in OM were distributed in a broad size range in the Longmaxi shale, which led to good pore connectivity and gas *** narrow pores(i.e., pores \ 20 nm) in OM–clay composites were found in the Niutitang shale, and might account for this shale's poor pore connectivity and low gas production efficiency. Enhancing the connectivity of the mesopores(especially pores \ 20 nm and those developed in OM–clay composites) might be the key to improving development of the Niutitang shale. The findings provide new insight into the formation and evolutionary mechanism of nanoscale pores developed in OM and clay minerals.

关键词： Nanoscale pore Clay minerals Organic matter OM-clay composites Pore distribution characteristics Pore connectivity

Structure and Evolution of Clay-Organic Nanocomposites in Three Leading Shales in China

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Journal of Earth Science 2023年第3期34卷 824-837页

作者： yuantao gu Quan Wan Xiaoxia Li Tao Han Shuguang Yang Qinhong Hu School of Resources and Environment Henan University of EngineeringZhengzhou 451191China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Shandong Provincial Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China University of Texas at Arlington Arlington Texas 76019USA

Organic matter(OM)in shales occurs as nanometer-sized intercalations with clay minerals that are termed as clay-organic nanocomposites;however,the OM occurrence in nanocomposites at different stages of maturation is still unclear,and the co-evolution process of OM and clay under burial is not well *** reveal the variation of OM occurrence and clarify the relationship between petroleum generation of OM&transformation of clay minerals in nanocomposites as a function of maturity,this study investigates the structure and clay-OM association in 44 samples from three leading shales at different maturity stages from two basins in China.A total of 15 samples of lacustrine shale from upper Triassic Yanchang Formation,15 samples of marine shale from Lower Silurian Longmaxi Formation,and 14 samples of marine shale from Lower Cambrian Niutitang Formation were analyzed based on organic geochemistry,X-ray diffraction(XRD),and field emission-scan electron microscopy(FE-SEM),focused ion beam(FIB)sample preparation and consequent high resolution-transmission electron microscopy(HR-TEM)observations combined with energy dispersive spectroscopy(EDS).The results from this study show that most shale samples are organic-rich,and these three shales represent thermal evolutionary process from oil-window mature to overmature in a sequence of Triassic Yanchang,Silurian Longmaxi,and Cambrian Niutitang *** observations indicate that sub-parallel bands of clays and intermingling of detrital minerals(such as quartz)dominate the nanocomposites in the Yanchang *** for Longmaxi and Niutitang shales,abundant nanopores and pyrite nanoparticles are observed in nanocomposites with features of layered distributions of OM and clay *** structural investigation of nanocomposites shows that organic carbon between multi-layers dominates the OM occurrence in nanocomposites,which significantly extends the traditional opinion of OM-clay *** an oil-window ma

关键词： organic matter shale clay-organic nanocomposites structure hydrocarbons

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MANET中TCP拥塞控制方法综述

中南大学学报（自然科学版） 2013年第1期44卷 156-165页

作者：刘洪全谷源涛清华大学电子工程系 95989部队

拥塞控制是MANET(mobile Ad-hoc NETwork)中的关键问题。MANET具有无线信号干扰大、信道衰落严重、多跳路由、链路不对称和网络拓扑动态扩展等特性,这些特性会使传统TCP(transmission control protocol)在发送数据过程中经历丢包率高、... 详细信息

拥塞控制是MANET(mobile Ad-hoc NETwork)中的关键问题。MANET具有无线信号干扰大、信道衰落严重、多跳路由、链路不对称和网络拓扑动态扩展等特性,这些特性会使传统TCP(transmission control protocol)在发送数据过程中经历丢包率高、应答包在中间节点累计、乱序包多和往返时间抖动大等问题,容易触发TCP作出错误的拥塞控制,进行不必要的超时重传、丢包重传和减小发送窗口大小,最终严重降低端到端的吞吐量。本文调研了近年来针对MANET提出的各种拥塞控制改进方法,按照拥塞产生的原因进行分类总结,详细介绍各个算法的工作原理并比较这些方法的技术特点。发现通过跨层设计获取网络实时状态信息,进而用来辅助拥塞控制,是改进方法的主流实现方式。

关键词：移动自组织网络拥塞控制无线多跳网络 TCP

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机器人定位中稳健的自适应粒子滤波算法

清华大学学报（自然科学版） 2005年第7期45卷 920-923页

作者：蒋正伟谷源涛唐昆清华大学电子工程系北京100084

为了提高粒子滤波算法在机器人定位中的性能,在基本粒子滤波算法的基础上,引入概率回退的方法对机器人的初始状态进行估计,采用窗口滤波更新粒子集合,根据对机器人位置估计的情况动态更新粒子集合的大小,得到一种改进的粒子滤波算法—... 详细信息

为了提高粒子滤波算法在机器人定位中的性能,在基本粒子滤波算法的基础上,引入概率回退的方法对机器人的初始状态进行估计,采用窗口滤波更新粒子集合,根据对机器人位置估计的情况动态更新粒子集合的大小,得到一种改进的粒子滤波算法——稳健的自适应粒子滤波算法。仿真结果表明:该算法充分利用了对机器人位置估计的有效信息,在显著提高算法稳健性的同时,降低了运算复杂度,较好地解决了机器人定位这一非线性非Gauss状态在线估计问题。

关键词：机器人定位粒子滤波 K—L(Kullback Leibler)距离概率回退

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国际地外样品储存与管理状态的对比和启示

南京大学学报（自然科学版） 2021年第6期57卷 971-980页

作者：张夏冬谷渊涛赵良南京大学地球科学与工程学院南京210023 南京大学地理与海洋科学学院南京210023

我国月球与深空探测规划中都有关于样品采集返回的任务,对这些地外返回样品的研究将极大地促进我国行星科学研究的发展.保证采集回的地外样品原始特征不被改变对于后续的科学研究至关重要.地外样品的储存与管理是一个复杂的系统工程.回... 详细信息

我国月球与深空探测规划中都有关于样品采集返回的任务,对这些地外返回样品的研究将极大地促进我国行星科学研究的发展.保证采集回的地外样品原始特征不被改变对于后续的科学研究至关重要.地外样品的储存与管理是一个复杂的系统工程.回顾并对比了美国、日本与欧洲(规划中)地外样品储存与管理设施的整体设计、惰性环境控制、设施材料选择、污染管理与清洁等方面的工作.基于已有设施的优缺点,进一步探讨了地外样品保管的新趋势与新挑战,以期对未来地外样品管理与储存工作提供借鉴和参考.

关键词：地外样品样品管理污染控制储存设施

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基于WPG的无人机一致性控制算法

深圳大学学报（理工版） 2019年第5期36卷 497-502页

作者：彭浩毛祥荟谷源涛王永程王玉清华大学电子工程系北京100084 盲信号处理国家级重点实验室成都610041

基于游走近端梯度(walk proximal gradient,WPG)提出无人机的一致性控制算法,并在高度对齐场景下进行建模实验.验证了算法在有路由与无路由两种情况下的性能,并在无路由情况下将WPG算法进行推广,且将推广的WPG算法与基于Gossip的方法相... 详细信息

基于游走近端梯度(walk proximal gradient,WPG)提出无人机的一致性控制算法,并在高度对齐场景下进行建模实验.验证了算法在有路由与无路由两种情况下的性能,并在无路由情况下将WPG算法进行推广,且将推广的WPG算法与基于Gossip的方法相结合.实验表明,在有路由情况下,算法可在有限的迭代次数下迅速收敛,且收敛精度高;在无路由情况下,算法具有很好的收敛性,并具有很高的通信效率,可大幅减小一致性过程中的通信开销.

关键词：控制理论一致性多智能体游走近端梯度高度对齐无人机

泥页岩中有机质-黏土复合体的微观结构、变形作用及源-储意义

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石油与天然气地质 2023年第2期44卷 452-467页

作者：李晓霞谷渊涛万泉杨曙光河南工程学院环境与生物工程学院河南郑州451191 南京大学地理与海洋科学学院江苏南京210023 中国科学院地球化学研究所矿床地球化学国家重点实验室贵州贵阳550081

泥页岩中的有机质和黏土矿物在沉积演化过程中能够相互结合形成有机质-黏土复合体,成为重要的生烃母质。基于大量的场发射扫描电镜和透射电镜观察分析,以中国鄂尔多斯盆地三叠系延长组、黔北奥陶系-志留系五峰组-龙马溪组、黔中寒武系... 详细信息

泥页岩中的有机质和黏土矿物在沉积演化过程中能够相互结合形成有机质-黏土复合体,成为重要的生烃母质。基于大量的场发射扫描电镜和透射电镜观察分析,以中国鄂尔多斯盆地三叠系延长组、黔北奥陶系-志留系五峰组-龙马溪组、黔中寒武系牛蹄塘组及南华北盆地二叠系山西组4套泥页岩储层为研究对象,详细查明了泥页岩中有机质-黏土复合体的微观结构及变形作用,并深入探讨了其源-储意义。泥页岩中有机质-黏土复合体成分复杂,形态多样,且易发生变形;驱动复合体发生变形的主要机制有构造应力作用、矿物颗粒作用、有机质赋存及黏土矿物转化。其中,由外部构造应力和复合体内部矿物颗粒对黏土层、有机质层挤压引起的变形能够改变复合体局部应力环境,所形成的拉张环境可使复合体发育大量纳米孔隙,且这些孔隙因黏土层的保护而不易发生烃类散失,可有效提升泥页岩的储集能力。相关结论有助于完善泥页岩的成岩理论,增进对页岩油气生成、运移和储集过程的认识,进而指导页岩油气的勘探开发。

关键词：微观结构变形作用拉张环境储集能力有机质-黏土复合体泥页岩

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