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Evaluating transmission towers potentials during ground faults

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 182-189页

作者： Maria VINTAN department of Electrical Engineering School of Engineering "Lucian Blaga" University of Sibiu Sibiu 550025 Romania

During ground faults on transmission lines,a number of towers near the fault are likely to acquire high potentials to *** tower voltages,if excessive,may present a hazard to humans and *** paper presents analytical methods in order to determine the transmission towers potentials during ground faults,for long and short *** author developed a global systematic approach to calculate these voltages,which are dependent of a number of *** of the most important factors are:magnitudes of fault currents,fault location with respect to the line terminals,conductor arrangement on the tower and the location of the faulted phase,the ground resistance of the faulted tower,soil resistivity,number,material and size of ground *** effects of these factors on the faulted tower voltages have been also examined for different types of power lines.

关键词：线路杆塔传输线路电位

Persistence of Cry1Ac Protein from Transgenic Bt Cotton Cultivation and Residue Returning in Fields and Its Effect on Functional Diversity of soil Microbial Communities

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Pedosphere 2019年第1期29卷 114-122页

作者： ZHANG Meijun FENG Meichen XIAO Lujie SONG Xiaoyan Guangwei DING YANG Wude College of Agriculture Shanxi Agricultural University department of Chemistry Northern State University

The persistence of Cry1 Ac protein in the soil and its effect on soil microbial communities are a core issue in assessing the ecological risk of transgenic Bacillus thuringiensis(Bt) cotton. In this study a field experiment was conducted on the cultivation of transgenic Bt cotton(Jin 26 and BtJ i 668) with the immediate returning of residues to the fields, in order to quantify the Cry1 Ac protein content in the fields and investigate its effects on the functional diversity of soil microbial communities. Cry1 Ac protein in the residue-soil mixture was gradually degraded in the transgenic Bt cotton fields. After transgenic Bt cotton straw was returned to the fields for 30 d, 63.73%and 58.33% of the initial amounts of Cry1 Ac protein were degraded in the Jin 26 and BtJ i 668 fields, respectively. Before the crops were sown in the following year(180 d after returning the straw), no Cry1 Ac protein was detected in the fields. After returning the cotton straw to the fields for 30 d, the Shannon-Wiener and McIntosh indices of soil microbial communities in the transgenic Bt cotton fields were significantly higher than those in the non-transgenic cotton fields. Meanwhile, the utilization of carbon sources including amino acids, amines, and carbohydrates by the soil microbial communities significantly increased. Both the McIntosh index and the utilization of carbohydrates increased until 180 d. Principal component analysis revealed that amino acids, amides, and carbohydrates were the main carbon sources distinguishing the two principal component factors. These findings indicated that Cry1 Ac protein did not accumulate in the fields after transgenic Bt cotton was planted for one year and the residues were immediately returned to the fields; however, the original functional diversity of soil microbial communities was affected continuously.

关键词： Biolog GN2 carbon source utilization diversity index principal component analysis straw return

Prediction of Strength Properties of Soft soil Considering Simple soil Parameters

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Open Journal of Civil Engineering 2023年第3期13卷 479-496页

作者： Md. Janibul Hoque Md. Bayezid Ahnaf Rafi Sharan Mozaher Ul Kabir Tahsin Tareque department of Civil and Environment Engineering Islamic University of Technology Gazipur Bangladesh

Cohesion is an important soil strength parameter for the overall structure and quality of building foundations as well as slope stability. For a civil engineering project, cohesion (c) can be determined directly from mainly unconfined compression tests, direct shear tests, and triaxial tests of soil. However, it’s quite challenging to collect soil samples as there are time and cost constraints, as well as a diversity of soil deposits. Hence, this research aims to demonstrate a simplified method in order to determine the strength parameter of cohesive soil. Here, we propose an alternative solution adopting statistical correlations and machine learning techniques to establish correlations between the liquid limit, plastic limit, moisture content and %fine of soil with the strength parameter. In laboratory testing, these parameters can be obtained easily and these tests are relatively simple, quick to perform and also comparatively inexpensive. Hence, several test results were used from 100 boreholes which were soft soil or silty clay-type soil. Using the collected in-situ and lab test results of soil samples, a Multiple Linear Regression (MLR), Random Forest Regression (RFR) and Machine Learning (ML) model will be developed to establish a relationship between cohesion and the available test results. In order to assess the performances of both models, several performance indicators like: correlation coefficient (R2), mean squared error (MSE), root mean square error (RMSE), and mean average error (MAE) will be used. These correlation coefficients will be used to demonstrate the prediction capacity and accuracy of both models. It should be noted that this approach will substitute the conventional testing required for strength parameters, which is both expensive and time-consuming.

关键词： Cohesion MLR RFR ML MSE RMSE MAE

Aluminum soil Chemistry: Influence on soil Health and Forest Ecosystem Productivity

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Agricultural Sciences 2022年第8期13卷 917-935页

作者： Michael Aide department of Agriculture Southeast Missouri State University Cape Girardeau USA

soil aluminum phytotoxicity has been a major research area since the inception of modern soil science. Acid soils, which typically manifest plant aluminum toxicity, are frequently dedicated to food production, thus yield and quality reductions influence food security. This manuscript reviews our modern understanding of 1) soil aluminum hydrolysis and polymerization, 2) aluminum complexation with inorganic and organic anions, 3) aluminum interference with vital plant physiological processes, 4) aluminum and forest ecosystem productivity, and 5) demonstrates the software simulation of aluminum reactivity and its role in predicting soil behavior. The manuscript also provides a perspective for future soil-aluminum research critical to maintaining food security and food quality.

关键词： Aluminum soil Acidity Hydrolysis Rhizosphere soil Health

Non-Pneumatic Tire Design and Modeling: An Overview of Research

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Journal of Applied Mathematics and Physics 2023年第11期11卷 3529-3564页

作者： Charanpreet Singh Sidhu Zeinab El-Sayegh department of Automotive and Mechatronics Engineering Ontario Tech University Oshawa Canada

The research provides valuable insights into the intricate world of Non-Pneumatic (NP) tire technology, covering various facets from modeling and validation to material properties, design optimization, and tire-soil interactions. It begins with an exploration of existing NP tire modeling techniques, emphasizing the importance of accurate and reliable models for NP tires, including static and dynamic validation methods, and demonstrating the influence of structural features and material properties on tire performance. The review emphasizes the challenges and prospects of NP tires and aims to support the development of innovative airless tire solutions. The reviewed papers collectively contribute to a deeper understanding of NP tires, their applications, and potential enhancements in performance and efficiency across various industries.

关键词： Non-Pneumatic Tires Finite Element Analysis Tire Mechanics Vehicle Dynamics

An Urban Road Risk Assessment Framework Based on Convolutional Neural Networks

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International Journal of Disaster Risk Science 2023年第3期14卷 475-487页

作者： Juncai Jiang Fei Wang Yizhao Wang Wenyu Jiang Yuming Qiao Wenfeng Bai Xinxin Zheng department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Safety Science and Technology Tsinghua Shenzhen International Graduate SchoolShenzhen 518000China Guangzhou Metro Design Research Institute Co. LtdGuangzhou 510010China

In contemporary cities,road collapse is one of the most common *** study proposed a framework for assessing the risk of urban road *** framework first established a risk indicator system that combined environmental and anthropogenic factors,such as soil type,pipeline,and construction,as well as other ***,an oversampling technique was used to create the *** framework then constructed and trained a convolutional neural network(CNN)-based model for risk *** experimental results show that the CNN model(accuracy:0.97,average recall:0.91)outperformed other *** indicator contribution analysis revealed that the distance between the road and the construction site(contribution:0.132)and the size of the construction(contribution:0.144)are the most significant factors contributing to road *** to the natural breaks,a road collapse risk map of Foshan City,Guangdong Province,was created,and the risk level was divided into five *** 3%of the roads in the study area are at very high risk,and 6%are at high risk levels,with the high risk roads concentrated in the east and *** risk map produced by this study can be utilized by local authorities and policymakers to help maintain road safety.

关键词： Convolutional neural networks Data augmentation Risk assessment Urban road collapse

1988年以后波罗的海国家和瑞典的农业发展与养分流动

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AMBIO－人类环境杂志 1999年第4期28卷 320-327页

作者： Stefan Lfgren Arne Gustafson Staffan Steineck Per St■hlnacke 闵庆文187 department of Environmental Assessment Swedish University of Agricultural Sciences P. O. Box 7050 S-750 07 Uppsala Sweden Division of water Quality Management Swedish University of Agricultural Sciences P. O. Box 7072 S-750 07 Uppsala Sweden Dept. of soil Sciences Swedish University of Agricultural Sciences P. O. Box 7014 S-750 07 Uppsula Sweden Jordforsk Dept. of Soil & Environmental ResearchN-1432 sNorway 中国科学院自然资源综合考察委员会

1990年3～8月,爱沙尼亚、拉脱维亚和立陶宛宣布从苏联独立。独立之后,波罗的海沿岸国家的农业从原来以庞大的集体农场为特征的国有经济,转变为以私有家庭农场为特征的市场经济。由于财政原因,无机肥的使用量下降到50年代的水平。1994年... 详细信息

1990年3～8月,爱沙尼亚、拉脱维亚和立陶宛宣布从苏联独立。独立之后,波罗的海沿岸国家的农业从原来以庞大的集体农场为特征的国有经济,转变为以私有家庭农场为特征的市场经济。由于财政原因,无机肥的使用量下降到50年代的水平。1994年饲用牧草和饲料作物的产量仅分别为瑞典的40%和50%。由于出口的减少,波罗的海国家肉、奶、蛋总产量从1989年到1994年下降了40%～50%。本研究的目的是探讨独立以后波罗的海国家农业中氮、磷流动的变化,并与同期瑞典农业生产情况进行比较,特别是关于养分流动的变化,是否已经引起了养分从渡罗的海国家向波罗的海径流的变化。

关键词：波罗的海国家瑞典农业发展农业经济养分流动

Characteristics of tailings from metal mines in Hunan Province, China

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Journal of Central South University of Technology 2005年第2期12卷 225-228页

作者：刘云国张慧智曾光明黄宝荣李欣徐卫华 department of Environmental Science and Engineering Hunan UniversityChangsha 410082 China

The tailing soils were from 10 mining areas in Hunan Province. To predict the potential impact of tailings on nearby environments, the characteristics such as the pH value, loss on ignition, cation exchange capacity, and the concentration and speciation of heavy metals in the tailings were investigated. Based on these characteristics, the pollution index and danger index were calculated so as to evaluate the priorities of remediation. The results show that the concentrations of Pb, Cd, Cu and Zn exceed the tolerable levels of the phytotoxicity in the most tailings. The large proportion of heavy metals exists in the form of residual fraction in most tailings, followed by sulfides/organic and Fe/Mn oxide fractions, and a little in the exchangeable and carbonate fraction. The calculated pollution indices for the tailing samples range from 1.41 to 83.42, which indicates that all the tailings contain heavy metals at a level that causes toxicity to the ecosystem. The danger indices for the tailing samples range from 0.06 to 387.00. The highest value of the danger indices is that of Yongzhou sample, reaching 387.00; the lowest one is that of Xikuangshan sample, only 0.06. Considering the results of pollution index and danger index in combination, the priority of remediation is determined to be Yongzhou, Baoshan, Xiangtan and Lengshuijiang.

关键词：重金属土壤尾矿污染指数

Seed priming with Pseudomonas putida isolated from rhizosphere triggers innate resistance against Fusarium wilt in tomato through pathogenesis-related protein activation and phenylpropanoid pathway

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Pedosphere 2020年第5期30卷 651-660页

作者： Nellickal Subramanyan JAYAMOHAN Savita Veeranagouda PATIL Belur Satyan KUMUDINI department of Biotechnology School of SciencesJAIN(Deemed-to-be University)Bengaluru 560011(India)

Pathogenesis-related(PR)proteins are one of the major and preliminary proteins accumulated as a defense against biotic *** defense response can be induced by using beneficial rhizobacteria,which has been studied in various host-pathogen *** the present study,eleven Pseudomonas isolates were assessed for their potential to ferment sorbitol,reduce nitrate,and produce mycolytic enzymes,1-aminocyclopropane-l-carboxylic acid(ACC)deaminase,phenazine antibiotics,and N-acyl homoserine lactones(AHLs).All isolates were tested against the host-specific pathogen Fusarium oxysporum MTCC1755 in tomato under greenhouse conditions,and shortlisted isolates were tested for their rhizosphere ***-vitro test results showed that the isolates were able to produce mycolytic enzymes,including protease,lipase,chitinase,cellulase,and amylase,and the antibiotic phenazine and were negative for *** the isolates except two were positive for ACC deaminase *** results showed that the isolates M80,M96,and T109 significantly reduced symptoms of Fusarium *** greenhouse tests under autoclaved and unautoclaved soil conditions showed that M80,M96,and T109 were excellent rhizosphere competitors and were identified as Pseudomonas *** brief,the defense-specific biochemical variations in the host could describe the improved defense against Fusarium wilt occurring in the primed *** three Pseudomonas strains could be used as potential biocontrol agents,along with their rhizosphere competence.

关键词： 1-aminocyclopropane-l-carboxylic acid(ACC)deaminase biocontrol agent disease incidence mycolytic enzymes host-specific pathogen rhizosphere competence