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Effects of Typical Soil and Stratification Thickness on Water Infiltration Characteristics in Central Ningxia

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Meteorological and Environmental Research 2024年第4期15卷 58-65页

作者： tianwen zhang Wei CHEN Xiaoying CHEN Rongjun ZHI Lin CHEN Haibo zhang Wei LIANG Ningxia Hui Autonomous Region Institute of Mineral Geology Yinchuan 750021China Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwest China Ministry of Education(Ningxia University)Yinchuan 750021China College of Ecology and Environment Ningxia UniversityYinchuan 750021China

In order to compare the influence of different soil types and stratification on water infiltration capacity,two main types of soil in the desert steppe,sierozem(S)and aeolian sandy soil(A),were selected,and infiltration simulation tests were conducted on homogeneous soil and layered soil(layer thickness 5,10,and 20 cm),*** results show that during the whole experiment,there was a small difference between S5A95(aeolian sandy soil 95 cm thick was covered with sierozem 5 cm thick)and S10A90(aeolian sandy soil 90 cm thick was covered with sierozem 10 cm thick)in the wetting front process,infiltration rate and cumulative infiltration,but there was a significant difference between S5A95 and S20A80(aeolian sandy soil 80 cm thick was covered with sierozem 20 cm thick).In the initial infiltration stage,there was no significant difference between A5S95(sierozem 95 cm thick was covered with aeolian sandy soil 5 cm thick)and A10S90(sierozem 90 cm thick was covered with aeolian sandy soil 10 cm thick).However,with the increase of infiltration time,the wetting front process,A5S95,A10S90 and A20S80 had significant differences in terms of wetting front process,infiltration rate and cumulative *** infiltration capacity of A was significantly higher than that of *** with linear R 2 value and model parameters,the three infiltration models were comprehensively compared,and the fitting process and results of the general empirical model for the infiltration process of homogeneous soil and layered soil showed good *** models were used to simulate the water infiltration process of layered soil with different textures,and the order of the effect is as follows:general empirical model>Kostiakov model>Philip *** type and layer thickness had a great influence on water infiltration *** sierozem was covered with aeolian sandy soil 20 cm thick,the infiltration capacity was the *** aeolian sandy soil was covered with sierozem 10 cm thic

关键词： Soil type Layer thickness Water infiltration Desert steppe

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厦门地区预制中短管桩抗压承载力统计分析

工程勘察 2024年第3期52卷 29-37页

作者：张添文福建省建科院检验检测有限公司福建厦门361006 福建省绿色建筑技术重点实验室福州350025 福建省建筑科学研究院有限责任公司福州350025

本文收集了厦门地区27根φ500预制中短管桩(桩长为4.9~14.8m,桩端持力层为黏性土—强风化花岗岩)的抗压静载试验结果,采用极差法、修正箱线图法和勘察规范统计法对27根桩的抗压极限承载力分九种情况进行了归纳分析与统计,得出了预制中... 详细信息

本文收集了厦门地区27根φ500预制中短管桩(桩长为4.9~14.8m,桩端持力层为黏性土—强风化花岗岩)的抗压静载试验结果,采用极差法、修正箱线图法和勘察规范统计法对27根桩的抗压极限承载力分九种情况进行了归纳分析与统计,得出了预制中短管桩桩长宜按15m界定,其对应的短桩效应承载力折减经验系数为0.84等具有实际应用价值的经验参数,同时也剖析了极差法、修正箱线图法和勘察规范统计法的优缺点。

关键词：预制中短管桩抗压极限承载力试设比极差法修正箱线图法勘察规范统计法短桩效应承载力折减经验系数

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基于功率信号分析的光伏电站故障诊断方法

电力系统及其自动化学报 2024年第5期36卷 150-158页

作者：郑晏厉小润张天文浙江大学电气工程学院杭州310027 浙江正泰智维能源服务有限公司杭州310052

为提高光伏电站故障诊断精度,提出一种基于功率信号分析的光伏电站故障诊断方法。首先,用卷积神经网络结合长短记忆CNN-LSTM(convolutional neural networks-long short-term memory)模型和岭回归模型对历史发电的时序信息进行充分挖掘... 详细信息

为提高光伏电站故障诊断精度,提出一种基于功率信号分析的光伏电站故障诊断方法。首先,用卷积神经网络结合长短记忆CNN-LSTM(convolutional neural networks-long short-term memory)模型和岭回归模型对历史发电的时序信息进行充分挖掘,再依据实际与预测发电功率之间的动态时间规整DTW(dynamic time warping)距离进行电站故障检测;其次,提出一个基于实际发电功率频域特征的故障分类指标,建立分类规则库,将电站故障分为通信故障、设备故障、限电故障,结合故障影响等效发电小时数评估电站故障程度;最后,通过算例分析验证了该算法的有效性。

关键词：故障检测故障分类光伏电站时序分析频域分析

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基于掩模注意型交互的SAR舰船实例分割

系统工程与电子技术 2024年第3期46卷 831-838页

作者：张天文张晓玲邵子康曾天娇电子科技大学信息与通信工程学院四川成都611731 电子科技大学航空航天学院四川成都611731

现有合成孔径雷达(synthetic aperture radar,SAR)舰船实例分割方法未实现掩模交互或交互性能有限,导致检测精度较低。针对上述问题,提出了一种基于掩模注意型交互(mask attention interaction,MAI)的SAR舰船实例分割方法MAI-Net。首先,... 详细信息

现有合成孔径雷达(synthetic aperture radar,SAR)舰船实例分割方法未实现掩模交互或交互性能有限,导致检测精度较低。针对上述问题,提出了一种基于掩模注意型交互(mask attention interaction,MAI)的SAR舰船实例分割方法MAI-Net。首先,MAI-Net使用了膨胀空间金字塔池化,来获取多分辨率特征响应,增强了对背景的鉴别能力。其次,MAI-Net使用了非局部注意力模块来抑制低价值信息,实现了空间特征自注意。最后,MAI-Net提出了拼接混洗注意力模块来平衡不同特征图的贡献,进一步提高了实例分割精度。在公开的像素级多边形分割SAR舰船检测数据集(polygon segmentation SAR ship detection dataset,PSeg-SSDD)上的实验结果表明,MAI-Net的SAR舰船实例分割精度高于现有其他11种对比模型,实例分割精度达到61.1%,高于次优模型1.5%。

关键词：合成孔径雷达深度学习实例分割掩模注意型交互

基于锚框自适应和多尺度增强的SAR舰船检测

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系统工程与电子技术 2024年第4期46卷 1204-1211页

作者：邵子康张晓玲张天文曾天娇电子科技大学信息与通信工程学院四川成都611731 电子科技大学航空航天学院四川成都611731

针对目前基于深度学习的合成孔径雷达(synthetic aperture radar, SAR)舰船检测锚框尺度固定、多尺度检测性能较差的问题,提出了一种基于锚框自适应和多尺度增强网络(adaptive anchor multi-scale enhancement network, AA-MSE-Net)的SA... 详细信息

针对目前基于深度学习的合成孔径雷达(synthetic aperture radar, SAR)舰船检测锚框尺度固定、多尺度检测性能较差的问题,提出了一种基于锚框自适应和多尺度增强网络(adaptive anchor multi-scale enhancement network, AA-MSE-Net)的SAR舰船检测方法。首先,AA-MSE-Net引入了锚框自适应机制,来生成适应目标形态的高质量锚框,增强了舰船形态描述能力。其次,AA-MSE-Net提出了多尺度增强金字塔网络,来融合增强多尺度特征,增强了多尺度描述能力。最后,AA-MSE-Net在骨干网络中引入了可变形卷积,来提取舰船形变特征,进一步提高检测精度。实验证明,AA-MSE-Net在公开SAR舰船检测数据集上的平均精度高于8种对比方法。

关键词：合成孔径雷达舰船检测自适应锚框尺度增强

3D stability analysis method of concave slope based on the Bishop method

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International Journal of Mining Science and Technology 2017年第2期27卷 365-370页

作者： zhang tianwen Cai Qingxiang Han Liu Shu Jisen Zhou Wei School of Mines China University of Mining and TechnologyXuzhou 221116China Xiaolongtan Mining Administration Kaiyuan 661699China

In order to study the stability control mechanism of a concave slope with circular landslide, and remove the influence of differences in shape on slope stability, the limit analysis method of a simplified Bishop method was employed. The sliding body was divided into strips in a three-dimensional model, and the lateral earth pressure was put into mechanical analysis and the three-dimensional stability analysis methods applicable for circular sliding in concave slope were deduced. Based on geometric structure and the geological parameters of a concave slope, the influence rule of curvature radius and the top and bottom arch height on the concave slope stability were analyzed. The results show that the stability coefficient decreases after growth, first in the transition stage of slope shape from flat to concave, and it has been confirmed that there is a best size to make the slope stability factor reach a maximum. By contrast with average slope, the stability of a concave slope features a smaller range of ascension with slope height increase, which indicates that the enhancing effect of a concave slope is apparent only with lower slope heights.

关键词： Bishop method Concave slope Three-dimensional structure Stability analysis

EVENT-DRIVEN SIMULATION OF INTEGRATE-AND-FIRE MODELS WITH SPIKE-FREQUENCY ADAPTATION

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Journal of Electronics(China) 2009年第1期26卷 120-127页

作者： Lin Xianghong zhang tianwen School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

The evoked spike discharges of a neuron depend critically on the recent history of its electrical activity. A well-known example is the phenomenon of spike-frequency adaptation that is a commonly observed property of neurons. In this paper, using a leaky integrate-and-fire model that includes an adaptation current, we propose an event-driven strategy to simulate integrate-and-fire models with spike-frequency adaptation. Such approach is more precise than traditional clock-driven numerical integration approach because the timing of spikes is treated exactly. In experiments, using event-driven and clock-driven strategies we simulated the adaptation time course of single neuron and the random network with spike-timing dependent plasticity, the results indicate that （1） the temporal precision of spiking events impacts on neuronal dynamics of single as well as network in the different simulation strategies and （2） the simulation time in the event-driven simulation strategies. scales linearly with the total number of spiking events

关键词： Integrate-and-fire neuron Spike-frequency adaptation Event-driven Simulation

Studies of biouptake and transformation of mercury by a typical unicellular diatom Phaeodactylum tricornutum

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Chinese Science Bulletin 2013年第2期58卷 256-265页

作者： DENG GuiFu zhang tianwen YANG LiMin WANG QiuQuan Department of Chemistry & the Key Laboratory of Analytical Science College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Marine Environmental Science Xiamen University

Mercury(Hg) is a toxic heavy metal with its biogeochemical cycling in the ocean depending on the type and behavior of the oceanic *** present work aimed to evaluate bioaccumulation and transformation of Hg by Phaeodactylum tricornutum,a typical unicellular diatom,when exposed to the extremely high level of Hg in order to understand the possible mechanisms of acute stress *** can accumulate Hg(its bioaccumulation factor is at 104 level),and the 96 h EC 50 was estimated to be 145μg *** amounts of surface-bound Hg being about 1.2 to 4.8 times higher than those of intracellular Hg under exposure to HgCl 2(from 20 to 120μg L-1 concentrations) suggested that the cell wall of *** is an important "fence" towards *** entering the *** cell,Hg underwent transformation in its chemical form via interactions with high molecular weight sulfur-containing proteins(accounting for 68% of the intracellular Hg),and glutathione as well as the induced phytochelatins(PCs)(24% Hg) which alleviated the toxicity of *** addition,the existence of organic ligands greatly influenced the uptake and transformation behavior of *** towards HgCl2,especially in the case of cysteine(Cys),which increased the uptake of Hg,but alleviated the toxicity of Hg towards *** due to the fact that Cys is an important precursor for the synthesis of PCs inside the *** uptake process of Hg by *** was in agreement with the Freundlich isotherm,suggesting a typical heterogeneous sorption *** importantly,we observed the conversion of HgCl2 into methylmercury inside the *** cells and its release into the culture solution using HPLC/CVG-AFS and GC-MS,although the mechanism needs to be further investigated.

关键词：三角褐指藻氯化汞单细胞改造硅藻生物地球化学循环 HgCl2 吸收过程

Effect of Feeding Strategies on Molecular Responses of Biotransformation Genes in Crassostrea gigas Exposed to Cadmium

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Journal of Ocean University of China 2019年第4期18卷 883-888页

作者： SUN Ming LIU Guangbin LIN Hong zhang tianwen GUO Wen Marine Biology Institute of Shandong Province Qingdao 266104 China College of Food Science and Engineering Ocean University of China Qingdao 266003 China

Heavy metals, including cadmium (Cd), are widespread pollutants of great environmental concern because of their ac- cumulation and toxicity. Environmental conditions can affect the accumulation and elimination of Cd in organisms. The aim of this study is to understand the respective responses of metallothioneins (MTs), P-glycoprotein (P-gp), and heat shock protein 70 (hsp70) genes in the mantle and digestive gland of the oyster Crassostrea gigas exposed to 10 g L 1 Cd for 28 days, followed by a depura- tion period of 35 days under different feeding strategies. The MT expression in the digestive gland was higher than in mantle, and was induced in a fluctuating pattern throughout the time of the whole experiment when the oyster was exposed to Cd. The results indicated an enhanced MT activity is required for Cd detoxification. Expression levels of P-gp in the mantle of Cd-exposed oysters fed with algae increased in the first two weeks of the accumulation phase. Then the induction weakened, but the expression still in- creased significantly compared with the control group fed without algae. The P-gp levels in the digestive gland were under-regulated during both the contamination and decontamination periods except in the group fed with Dicrateria inornata at day 0.083. The in- duction of P-gp is possibly related to the important role of pumping Cd out of the cell, while a major implication of P-gp expression inhibition would be a disruption of the protein synthesis. Hsp70 expression exhibited an overall decreasing trend. The highest relative hsp70 inhibition occurred during day 42 to day 63, with approximately 4-fold and 10-fold lower hsp70 levels as compared to the *** feeding with no algae in the mantle and digestive gland, respectively. The induction of hsp70 may be explained by the re- folding of protein in presence of Cd, followed by the inhibition of hsp70 when the protein synthesis was disrupted.

关键词： cadmium metallothionein P-glycoprotein heat shock protein 70 Crassostrea gigas feeding strategies