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Estimating the effect of urease inhibitor on rice yield based on NDVI at key growth stages

Kailou LIU,Yazhen LI,Huiwen HU

《农业科学与工程前沿（英文）》 2014年 第1卷 第2期   页码 150-157 doi: 10.15302/J-FASE-2014028

摘要： The effect of the urease inhibitor, N-(n-butyl) thiophosphoric triamide (NBPT) at a range of application rates on rice production was examined in a field experiment at Jinxian County, Jiangxi Province, China. The normalized difference vegetation index (NDVI) was measured at key growth stages in both early and late rice. The results showed that the grain yield increased significantly when urea was applied with NBPT, with the highest yield observed at 1.00% NBPT (wt/wt). NDVI differed with the growth stage of rice; it remained steady from the heading to the filling stage. Rice yield could be predicted from the NDVI taken at key rice growing stages, with ranging from 0.34 to 0.69 in early rice and 0.49 to 0.70 in late rice. The validation test showed that RMSE (t·hm ) values were 0.77 and 0.87 in early and late rice, respectively. Therefore, it was feasible to estimate rice yield for different amounts of urease inhibitor using NDVI.

关键词： normalized difference vegetation index (NDVI)     N-(n-butyl) thiophosphoric triamide (NBPT)     rice     grain yield    

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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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Divergent Changes in Vegetation Greenness, Productivity, and Rainfall Use Efficiency Are Characteristic

Yang Yu,Ting Hua,Liding Chen,Zhiqiang Zhang,Paulo Pereira,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.012

摘要： Globally, vegetation has been changing dramatically. The vegetation–water dynamic is key to understanding ecosystem structure and functioning in water-limited ecosystems. Continual satellite monitoring has detected global vegetation greening. However, a greenness increase does not mean that ecosystem functions increase. The intricate interplays resulting from the relationships between vegetation and precipitation must be more adequately comprehended. In this study, satellite data, for example, leaf area index (LAI), net primary production (NPP) and rainfall use efficiency (RUE), were used to quantify vegetation dynamics and their relationship with rainfall in different reaches of the Yellow River Basin (YRB). A sequential regression method was used to detect trends of NPP sensitivity to rainfall. The results showed that 34.53% of the YRB exhibited a significant greening trend since 2000. Among them, 20.54%, 53.37%, and 16.73% of upper, middle, and lower reach areas showed a significant positive trend, respectively. NPP showed a similar trend to LAI in the YRB upper, middle, and lower reaches. A notable difference was noted in the distributions and trends of RUE across the upper, middle, and lower reaches. Moreover, there were significant trends in vegetation–rainfall sensitivity in 16.86% of the YRB’s middle reaches—14.08% showed negative trends and 2.78% positive trends. A total of 8.41% of the YRB exhibited a marked increase in LAI, NPP, and RUE. Subsequently, strategic locations reliant on the correlation between vegetation and rainfall were identified and designated for restoration planning purposes to propose future ecological restoration efforts. Our analysis indicates that the middle reach of the YRB exhibited the most significant variation in vegetation greenness and productivity. The present study underscores the significance of examining the correlation between vegetation and rainfall within the context of the high-quality development strategy of the YRB. The outcomes of our analysis and the proposed ecological restoration framework can provide decision-makers with valuable insights for executing rational basin pattern optimization and sustainable management.

关键词： Vegetation greenness     Vegetation productivity     Rainfall use efficiency     Sensitivity     Yellow River Basin    

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Unnormalized and normalized forms of gefura measures in directed and undirected networks

Raf GUNS,Ronald ROUSSEAU

《信息与电子工程前沿（英文）》 2015年 第16卷 第4期   页码 311-320 doi: 10.1631/FITEE.1400425

摘要： In some networks nodes belong to predefined groups (e.g., authors belong to institutions). Common network centrality measures do not take this structure into account. Gefura measures are designed as indicators of a node’s brokerage role between such groups. They are defined as variants of betweenness centrality and consider to what extent a node belongs to shortest paths between nodes from different groups. In this article we make the following new contributions to their study: (1) We systematically study unnormalized gefura measures and show that, next to the ‘structural’ normalization that has hitherto been applied, a ‘basic’ normalization procedure is possible. While the former normalizes at the level of groups, the latter normalizes at the level of nodes. (2) Treating undirected networks as equivalent to symmetric directed networks, we expand the definition of gefura measures to the directed case. (3) It is shown how Brandes’ algorithm for betweenness centrality can be adjusted to cover these cases.

关键词： Networks subdivided in groups     Partitions     Gefura measures     Q-measures     Brokerage role     Directed and undirected networks     Brandes’     algorithm    

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Temperature difference-powered carbon nanotube bearings

Quanwen HOU, Bingyang CAO, Zengyuan GUO

《能源前沿（英文）》 2011年 第5卷 第1期   页码 49-52 doi: 10.1007/s11708-010-0111-0

摘要： Molecular dynamics simulations are conducted to study the motion of carbon nanotube-based nanobearings powered by temperature difference. When a temperature difference exists between stator nanotubes, the rotor nanotubes acquire a higher temperature, which arises from the interaction between phonon currents and nanotubes. The thermal driving force increases with the increase in temperature difference between the stators, an increase that is nearly proportional to the temperature difference. Confined by the minimum energy track, the (5, 5)@(10, 10) nanotube bearings only translate along the axis direction but without successive rotation.

关键词： temperature difference-induced motion     carbon nanotubes     nanobearing     molecular dynamics simulation    

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类差分平衡函数的性质及其应用

张文英,李世取

《中国工程科学》 2004年 第6卷 第3期   页码 45-52

摘要：

定义了布尔函数的类差分和类差分平衡函数，研究了类差分平衡函数的密码学性质以及构造方法。作为类差分平衡函数的应用，给出了〓上逻辑函数是完全非线性函数的充要条件，并在首先分析得到所有四元类差分平衡函数的基础上，编程搜索出〓上所有的完全非线性函数。

关键词： Bent函数     完全非线性函数     2-基展开     类差分     类自相关函数     类差分平衡函数    

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Synthesis of Intermittent-Motion Linkages with Slight Difference in Length Between Links

CHEN Xin-bo, YU Zhen

《机械工程前沿（英文）》 2006年 第1卷 第1期   页码 76-79 doi: 10.1007/s11465-005-0007-6

摘要：

The design of intermittent-motion linkages using traditional methods is usually complicated. In this paper, (1) a new method for realizing intermittent motion, using linkages with a slight difference in length between links, is studied; (2) some new types of intermittent-motion linkages and their software for visual analysis and design are developed; and (3) influences of some design parameters on intermittent-motion characteristics are clarified. Results confirmed that the theory and the software are useful, making the synthesis of intermittent-motion linkages clear and easy.

关键词： synthesis     useful     intermittent     intermittent-motion     traditional    

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温差能与低温海水资源综合利用研究

付强,王国荣,周守为,钟林,张理,余兴勇,杨浦

《中国工程科学》 2021年 第23卷 第6期   页码 52-60 doi: 10.15302/J-SSCAE-2021.06.007

摘要：

我国海洋温差能资源量巨大，主要分布在广东省和南海海域，是区域能源结构优化以实现碳达峰、碳中和的有效支撑，也是未来我国南海、 21 世纪海上丝绸之路沿线诸多岛屿能源补给保障的重要途径；目前海洋温差能发电（ OTEC）技术和装备尚处于实验阶段，兆瓦级试验电站建设成本巨大，整体技术成熟度不及商业级利用规模，亟待发展突破。本文总结了国内外 OTEC 及综合利用的发展模式、技术装备所面临的挑战，针对南海温差能资源开发困境、广东省液化天然气（ LNG）冷能资源浪费等情况，提出了以 LNG 气化的低温海水替代深层海水进行温差能发电的新途径。建议以珠海 LNG 气化站为例，探索 LNG 冷能回收 – 温差能发电、低温冷海水综合利用示范基地的发展模式；通过初步概算示范基地的投资与收益，完成了相应模式的经济与技术可行性论证。相关发展模式建议、应用案例论证过程，可为我国温差能与低温海水资源综合利用提供技术借鉴和应用参考。

关键词： 海洋温差能     低温海水资源     LNG冷能     综合利用     温差能发电    

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Geosynthetics used to stabilize vegetated surfaces for environmental sustainability in civil engineering

Jie HAN,Jun GUO

《结构与土木工程前沿（英文）》 2017年 第11卷 第1期   页码 56-65 doi: 10.1007/s11709-016-0380-8

摘要： Geosynthetics, factory-manufactured polymer materials, have been successfully used to solve many geotechnical problems in civil engineering. Two common applications are earth stabilization and erosion control. Geosynthetics used for earth stabilization include but are not limited to stabilized slopes, walls, embankments, and roads. Geosynthetics used for erosion control are mostly related to slopes, river channels and banks, and pond spillways. To enhance environmental sustainability, vegetation has been increasingly planted on the facing or surfaces of these earth structures. Under such a condition, geosynthetics mainly function as surficial soil stabilization while vegetation provides green appearance and erosion protection of earth surfaces. Recently, geosynthetic or geosynthetic-like material has been used to form green walls outside or inside buildings to enhance sustainability. Geosynthetics and vegetation are often integrated to provide combined benefits. The interaction between geosynthetics and vegetation is important for the sustainability of the earth and building wall surfaces. This paper provides a review of the current practice and research in the geosynthetic stabilization of vegetated earth and building surfaces for environmental sustainability in civil engineering with the emphases on geosynthetic used for erosion protection, geosynthetic-stabilized slopes, geosynthetic-stabilized unpaved shoulders and parking lots, and geosynthetic-stabilized vegetated building surfaces.

关键词： erosion     geosynthetic     stabilization     sustainability     vegetation    

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The Difference Effect of Environmental Regulation on Two Stages of Technology Innovation in China’s Manufacturing

Bao-long Yuan,Sheng-gang Ren,Xing Hu,Xuan-yu Yang

《工程管理前沿（英文）》 2016年 第3卷 第1期   页码 24-29 doi: 10.15302/J-FEM-2016007

摘要： This paper divides technological innovation into two stages: technology development and technology transfer. Then the authors use the panel data of 28 manufacturing industries during 2003–2012 to test the econometric regression model for the industry of the sub stages, which is a regulation on technological innovation in the environment. The results show that: (1) environmental regulation has a significant role in promoting China’s manufacturing technology research patent achievements, and technology into new products, and this indicated that “Porter hypothesis” in the manufacturing sector has been verified; (2) R&D and transfer expenditure have a positive impact on technological innovation. Finally, the authors put forward the corresponding policy recommendations for industry of the environmental regulation on the impact of technological innovation in phases.

关键词： environmental regulation     technology innovation     stage difference     manufacturing    

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Three-dimensional finite difference analysis of shallow sprayed concrete tunnels crossing a reverse fault

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

《结构与土木工程前沿（英文）》 2020年 第14卷 第4期   页码 998-1011 doi: 10.1007/s11709-020-0621-8

摘要： Urban tunnels crossing faults are always at the risk of severe damages. In this paper, the effects of a reverse and a normal fault movement on a transversely crossing shallow shotcreted tunnel are investigated by 3D finite difference analysis. After verifying the accuracy of the numerical simulation predictions with the centrifuge physical model results, a parametric study is then conducted. That is, the effects of various parameters such as the sprayed concrete thickness, the geo-mechanical properties of soil, the tunnel depth, and the fault plane dip angle are studied on the displacements of the ground surface and the tunnel structure, and on the plastic strains of the soil mass around tunnel. The results of each case of reverse and normal faulting are independently discussed and then compared with each other. It is obtained that deeper tunnels show greater displacements for both types of faulting.

关键词： urban tunnel     sprayed concrete     reverse fault     normal fault     finite difference analysis    

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Sulfur mediated heavy metal biogeochemical cycles in coastal wetlands: From sediments, rhizosphere to vegetation

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1523-x

摘要：

• In sediments, the transformation of sulfides may lead to the release of heavy metals.

关键词： Coastal wetland     Heavy metal     Sulfur     Biogeochemical cycle    

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Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 59-65 doi: 10.1007/s11783-010-0259-1

摘要： Sorption isotherms of galaxolide (HHCB) of different fractions from two sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total sorption. The HHCB sorption isotherms that used the batch equilibration method were studied on different sediments of different fractions. The sorption isotherms of 600°C heating fractions were detailed using the linear model, while the other fractions were nonlinear and fitted well with the Freundlich model. The dissolved organic carbon (DOC) removed, NaOH extracted, and 375°C heating fractions showed more nonlinear sorption than the original sediments, which suggested more heterogeneous sorption sites in these fractions. Compared to the original sediments, the 375°C heating fractions had higher carbon-normalized distribution coefficient ( ) values, indicating a higher sorption affinity for HHCB. Among the different sediment fractions, the contribution of the 600°C heating fractions to the overall sorption were the lowest (<20%), while the 375°C heating fractions were the highest (up to 85%).

关键词： galaxolide (HHCB)     sorption     organic carbon     sediment     carbon-normalized distribution coefficient (Koc)    

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Changes of ecological conditions induced by rock tunneling in Laoshan Mountain area

LI Xiaozhao, ZHAO Xiaobao, WANG Zhongsheng

《结构与土木工程前沿（英文）》 2008年 第2卷 第4期   页码 366-370 doi: 10.1007/s11709-008-0056-0

摘要： Through field investigation, this paper examined the changes of ecological conditions induced by tunnel construction in Laoshan Mountain area, Nanjing, Jiangsu Province, P. R. China. The effects of habitat fragmentation and edge effect are examined and discussed. It is found that the environmental factors and vegetation situation have been influenced by the tunneling activity, and the disturbed area is approaching the sampling patch centre. The changed ecological conditions are beneficial for the settlement and growth of some herb and shrub species, and are unfavorable for the existence and growth of saplings, especially for the predominant species (e.g., robur) in this area. If the time of habitat fragmentation is long enough and there is no supplement from external areas, some vegetation species in the engineering influencing area will deteriorate, or even diminish in the future. The results can be used as a reference for the long-term ecological study in this area.

关键词： supplement     fragmentation     reference     tunneling activity     vegetation situation    

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Research on port ecological suitability evaluation index system and evaluation model

Yaofeng XIE,Xia LV,Ru LIU,Liuyan MAO,Xiaoxi LIU

《结构与土木工程前沿（英文）》 2015年 第9卷 第1期   页码 65-70 doi: 10.1007/s11709-014-0258-6

摘要： Along with the rapid development of port building, the negative impacts of port’s construction and operation on the coastline ecosystem are also increasingly strong. Therefore, it’s urgent to establish a scientific and complete system of port ecological suitability evaluation. This paper pointed out the characteristics of port ecological effects and the principles of selecting evaluation index, and used the “pressure-state-response (PSR)” model to analysis the various pressures on the environment caused by port construction and operation, and the system’s response. On this basis, we constructed the port ecological suitability evaluation index. This model used the combination of qualitative and quantitative analytic hierarchy process, to meet the multi-level, multi-objective characteristics of evaluation index system. The evaluation index system and evaluation model can be used to analysis the ecological suitability of port projects comprehensively and have some guiding significance to the port ecological suitability evaluation.

关键词： port     ecological suitability     press-state-response (PSR) model     evaluation index system    

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标题 作者 时间 类型 操作

Estimating the effect of urease inhibitor on rice yield based on NDVI at key growth stages

Kailou LIU,Yazhen LI,Huiwen HU

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

Divergent Changes in Vegetation Greenness, Productivity, and Rainfall Use Efficiency Are Characteristic

Yang Yu,Ting Hua,Liding Chen,Zhiqiang Zhang,Paulo Pereira,

期刊论文

Unnormalized and normalized forms of gefura measures in directed and undirected networks

Raf GUNS,Ronald ROUSSEAU

期刊论文

Temperature difference-powered carbon nanotube bearings

Quanwen HOU, Bingyang CAO, Zengyuan GUO

期刊论文

类差分平衡函数的性质及其应用

张文英,李世取

期刊论文

Synthesis of Intermittent-Motion Linkages with Slight Difference in Length Between Links

CHEN Xin-bo, YU Zhen

期刊论文

温差能与低温海水资源综合利用研究

付强,王国荣,周守为,钟林,张理,余兴勇,杨浦

期刊论文

Geosynthetics used to stabilize vegetated surfaces for environmental sustainability in civil engineering

Jie HAN,Jun GUO

期刊论文

The Difference Effect of Environmental Regulation on Two Stages of Technology Innovation in China’s Manufacturing

Bao-long Yuan,Sheng-gang Ren,Xing Hu,Xuan-yu Yang

期刊论文

Three-dimensional finite difference analysis of shallow sprayed concrete tunnels crossing a reverse fault

Masoud RANJBARNIA, Milad ZAHERI, Daniel DIAS

期刊论文

Sulfur mediated heavy metal biogeochemical cycles in coastal wetlands: From sediments, rhizosphere to vegetation

期刊论文

Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

期刊论文

Changes of ecological conditions induced by rock tunneling in Laoshan Mountain area

LI Xiaozhao, ZHAO Xiaobao, WANG Zhongsheng

期刊论文

Research on port ecological suitability evaluation index system and evaluation model

Yaofeng XIE,Xia LV,Ru LIU,Liuyan MAO,Xiaoxi LIU

期刊论文