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DPM 1

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几何平均强化算子 1

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强化学习；采样效率；采样过程；聚类方法；自动驾驶 1

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Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi

Sen DING, Yuan ZHANG, Bin LIU, Weijing KONG, Wei MENG

《环境科学与工程前沿（英文）》 2013年第7卷第5期页码 699-708 doi: 10.1007/s11783-013-0528-x

摘要： Riparian land use remains one of the most significant impacts on stream ecosystems. This study focuses on the relationship between stream ecosystems and riparian land use in headwater regions. Four riparian land types including forest, grassland, farmland, and residential land were examined to reveal the correlation between stream water and fish communities in headwater streams of the Taizi River in north-eastern China. Four land types along riparian of 3 km in length were evaluated at 25, 50, 100, 200 and 500 m widths, respectively. Generally, the results found a significant relationship between riparian land uses and stream water quality. Grassland was positively correlated with water quality parameters (conductivity and total dissolved solids) at scales from 100 to 500 m riparian width. Farmland and residential land was negatively correlated with water quality parameters at scales from 25 to 500 m and from 50 to 200 m riparian widths, respectively. Although the riparian forest is important for maintaining habitat diversity and fish communities, the results found that only fish communities were significantly correlated with the proportion of riparian farmland. Farmland had a positive correlation with individual fish abundance within a riparian corridor of 25 to 50 m, but a negative correlation with fish diversity metrics from 25 to 100 m. This study indicates that effective riparian management can improve water quality and fish communities in headwater streams.

关键词： fish water quality land use riparian buffer headwater stream

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Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

《环境科学与工程前沿（英文）》 2015年第9卷第2期页码 279-287 doi: 10.1007/s11783-014-0667-8

摘要： A riparian ecosystem is an ecological transition zone between a river channel and terrestrial ecosystems. Riparian ecosystems play a vital role in maintaining stream health and bank stabilization. The types of riparian vegetation have changed greatly because of human activities along the Wenyu River. This study examines the impact of riparian vegetation patterns on water pollution due to soil nutrient loss. Four riparian vegetation patterns from the river channel to the upland were chosen as the focus of this study: grassland, cropland, grassland-cropland, and grassland-manmade lawn. The different distributions of soil nutrients along vegetation patterns and the potential risk of nutrient loss were observed and compared. The results showed that riparian cropland has the lowest value of total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), and organic matter (OM), but it has the highest soil bulk density (BD). The distributions of soil TN, TP, AN, AP, and OM exhibited a declining trend from the upland toward the river channel for riparian cropland, whereas a different trend was observed for the riparian grassland. The vegetation patterns of grassland-cropland and grassland-manmade lawn show that the grassland in the lower slope has more nutrients and OM but lower soil BD than the cropland or manmade lawn in the upper slope. So, the lower-slope grassland may intercept and infiltrate surface runoff from the upland. The lower-slope grassland has higher levels of soil TN, TP, AN, and AP, and thus it may become a new source of nutrient loss. Our results suggest that the management of the riparian vegetation should be improved, particularly in densely populated areas, to control soil erosion and river pollution.

关键词： riparian vegetation patterns soil nutrient distribution nutrient loss management

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Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

《结构与土木工程前沿（英文）》 2013年第7卷第1期页码 50-54 doi: 10.1007/s11709-013-0186-x

摘要： Granular matter possesses impact-absorbing property due to its energy dissipation character. To investigate the impact-absorbing capacity of granular matter, the discrete element method (DEM) is adopted to simulate the impact of a spherical projectile on to a granular bed. The dynamic responses of the projectile are obtained for both thin and thick granular bed. The penetration depth of the projectile and the first impact peak are investigated with different bed thicknesses and impact velocities. Determining a suitable bed thickness is crucial to the buffering effect of granular matter. The first impact peak is independent of bed thickness when the thickness is larger than the critical thickness.

关键词： granular matter impact peak buffer capacity discrete element method critical thickness

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一类新的强化缓冲算子及其数值仿真

崔杰,党耀国,刘思峰,谢乃明

《中国工程科学》 2010年第12卷第2期页码 108-112

摘要：

根据新信息优先利用原理，在已有强化缓冲算子研究的基础上，构造一类新的强化缓冲算子，同时研究了它们的一些特性，克服了原有强化缓冲算子对序列新信息利用不够充分的缺陷，有效地解决了冲击扰动数据序列在建模型预测过程中常常出现的定量预测结果与定性分析结论不符的问题,算例仿真表明：与已有强化算子相比，这类新的强化缓冲算子显著地提高了GM(1,1)模型的预测精度。

关键词：算子强化缓冲算子几何平均强化算子 GM(1 1)

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Restoring soil health to reduce irrigation demand and buffer the impacts of drought

Rebecca SCHNEIDER, Stephen MORREALE, Zhigang LI, Erin MENZIES PLUER, Kirsten KURTZ, Xilu NI, Cuiping WANG, Changxiao LI, Harold VAN ES

《农业科学与工程前沿（英文）》 2020年第7卷第3期页码 339-346 doi: 10.15302/J-FASE-2020348

摘要：

Irrigation consumes three quarters of global water withdrawals each year. Strategies are needed to reduce irrigation water use, including increasing the efficiency of transfer methods and field application. Comprehensive restoration of soil health, specifically through organic matter amendments, can substantially reduce irrigation demand and increase crop yield. A program to restore severely degraded and desertified soils by incorporating coarse woodchips into the soil successfully increased rainfall capture and elevated soil moisture for several weeks between rainfall events at both Ningxia, north-west China and North Dakota, USA. With addition of fertilizer, woodchip incorporation further increased growth of wheat and alfalfa. Comprehensive soil health assessment of remnant grasslands was used to develop target reference soil profiles by which to guide restoration efforts. Given that most agricultural soils are degraded to some degree, soil health restoration can provide a powerful strategy toward achieving global food and water security.

关键词： drought irrigation restoration soil health woodchips

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Landing control method of a lightweight four-legged landing and walking robot

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0707-1

摘要： The prober with an immovable lander and a movable rover is commonly used to explore the Moon’s surface. The rover can complete the detection on relatively flat terrain of the lunar surface well, but its detection efficiency on deep craters and mountains is relatively low due to the difficulties of reaching such places. A lightweight four-legged landing and walking robot called “FLLWR” is designed in this study. It can take off and land repeatedly between any two sites wherever on deep craters, mountains or other challenging landforms that are difficult to reach by direct ground movement. The robot integrates the functions of a lander and a rover, including folding, deploying, repetitive landing, and walking. A landing control method via compliance control is proposed to solve the critical problem of impact energy dissipation to realize buffer landing. Repetitive landing experiments on a five-degree-of-freedom lunar gravity testing platform are performed. Under the landing conditions with a vertical velocity of 2.1 m/s and a loading weight of 140 kg, the torque safety margin is 10.3% and 16.7%, and the height safety margin is 36.4% and 50.1% for the cases with or without an additional horizontal disturbance velocity of 0.4 m/s, respectively. The study provides a novel insight into the next-generation lunar exploration equipment.

关键词： landing and walking robot lunar exploration buffer landing compliance control

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面向任务信息的层次化存储DPM策略

黄少珉,戚隆宁,杨军,胡晨

《中国工程科学》 2010年第12卷第2期页码 83-89

摘要：

面向层次化存储的DPM策略利用数据缓冲区实现请求集中从而延长PMC的空闲时间，可获得比传统策略更好的节能效果。在此基础上提出基于任务信息（task information based，TIB）的层次化存储DPM策略。TIB策略对任务的数据访问模式进一步细分，通过修改存储访问接口获知任务数据访问的模式，根据不同模式决定预读与替换算法，使策略具有更好的节能意识。

关键词：数据缓冲区任务信息 DPM 预读策略

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基于专家示教聚类经验池的高效深度强化学习 Research Article

王士珉1,赵彬琦1,张政锋1,张军平1,浦剑2

《信息与电子工程前沿（英文）》 2023年第24卷第11期页码 1541-1556 doi: 10.1631/FITEE.2300084

摘要：作为强化学习领域最基本的主题之一，样本效率对于深度强化学习算法的部署至关重要。与现有大多数从不同类型的后验分布中对动作进行采样的探索方法不同，我们专注于策略的采样过程，提出一种有效的选择性采样方法，通过对环境的内部层次结构建模来提高样本效率。具体来说，首先在策略采样过程中使用聚类方法生成动作候选集，随后引入一个用于对内部层次结构建模的聚类缓冲区，它由同轨数据、异轨数据以及专家数据组成，用于评估探索阶段动作候选集中不同类别动作的价值。通过这种方式，我们的方法能够更多地利用专家示教数据中的监督信息。在6种不同的连续运动环境中进行了实验，结果表明选择性采样方法具有卓越的强化学习性能和更快的收敛速度。特别地，在LGSVL任务中，该方法可以减少46.7%的收敛步数和28.5%的收敛时间。代码已开源，见https://github.com/Shihwin/SelectiveSampling。

关键词：强化学习；采样效率；采样过程；聚类方法；自动驾驶

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过氧化氢作为环境胁迫指标在植被管理中的应用 Article

Takashi Asaeda, Senavirathna Mudalige Don Hiranya Jayasanka, Li-Ping Xia, Abner Barnuevo

《工程（英文）》 2018年第4卷第5期页码 610-616 doi: 10.1016/j.eng.2018.09.001

摘要：

适应性植被管理非常耗时，其需要长时间的野外监测以获取可靠的数据。目前适应性植被管理手段虽已被广泛应用，但在进行栖息地状况评估时，仍然依赖于长时间的野外观测。目前的植被相关研究中，活性氧类（ROS）已经被视为一种环境胁迫指标。在这些ROS中，过氧化氢（H₂O₂）相对稳定，并且可以被准确、方便地量化。植物中H₂O₂含量可以被用作岸生和水生植被管理过程的胁迫指标，同时可以用来评估栖息地中单一植物物种的生长状况。本研究证明了植被管理中应用H₂O₂作为定量化环境胁迫指标的可行性。在实验室和野外（日本的真嗣湖、沙巴河、伊诺河和海河）条件下，分别开展了不同胁迫程度下大型水生植物和岸生植物生成H₂O₂情况的研究，结果表明H₂O₂可以作为环境管理中的胁迫指标。

关键词：大型植物河岸边区域环境梯度胁迫指标活性氧类过氧化氢

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马尔可夫中断下停止等待自动重传请求协议的性能分析 Regular Papers-Research Articles

Dashdondov KHONGORZUL, Yong-Ki KIM, Mi-Hye KIM

《信息与电子工程前沿（英文）》 2019年第20卷第9期页码 1296-1306 doi: 10.1631/FITEE.1700185

摘要：讨论了一种使用停止等待自动重传请求协议的语音数据集成分组多路复用器的性能。假设输入数据流量经泊松过程呈指数增长，且各数据包在单时隙中传输。同时，假设仅存在单一语音信号，其比数据包有更高优先级，且其流量通过开关马尔可夫过程给出。一旦语音信号被激活，则占用输出链路，阻塞数据包。引入缓冲器占用概念简化分析，并发现当中断信号通过马尔可夫过程给出时，使用停止等待自动重传请求协议的数据多路复用器表现出排队延迟和缓冲行为。仿真结果验证了分析结果的有效性。

关键词：自动重传请求协议；马尔可夫中断；泊松分布；缓冲器占用；等待时间

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标题作者时间类型操作

Effects of riparian land use on water quality and fish communities in the headwater stream of the Taizi

Sen DING, Yuan ZHANG, Bin LIU, Weijing KONG, Wei MENG

期刊论文

Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case

Erhui GUO,Liding CHEN,Ranhao SUN,Zhaoming WANG

期刊论文

Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

期刊论文