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Comparison of optimal capacitor placement methods in radial distribution system with load growth and ZIP load model

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

《能源前沿（英文）》 2013年 第7卷 第2期   页码 197-213 doi: 10.1007/s11708-013-0249-7

摘要： In this paper, a combined power loss sensitivity (PLS) index-based approach is proposed to determine the optimal location of the capacitors in the radial distribution system (RDS) based on the real and reactive combined loss sensitivity index, as capacitor placement not only reduces real power loss with voltage profile improvement but also reduces reactive power loss due to the reactive power compensation in the network. The results have been obtained with the existing methods of power loss index (PLI) and index vector (IV) method for comparison. Besides, the optimal placement has been obtained with the proposed method as well as existing methods and the total kVar support has been obtained. In addition, the results of net cost savings for the 10-, 34-, and 69-bus systems are obtained for comparison. Moreover, the results have been obtained for a large system of 85 buses to validate the results with combined sensitivity based approach. Furthermore, the load growth factor has been considered in the study which is essential for the planning and expansion of the existing systems, whereas the impact of the realistic load model as ZIP load model has been considered for the study of all the systems.

关键词： load growth     load models     reactive power compensation     radial distribution system     power loss index (PLI)     power loss sensitivity (PLS)     index vector (IV)    

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Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 56-67 doi: 10.1007/s11705-022-2185-8

摘要： Separation of vanadium from black shale leaching solution at low pH is very meaningful, which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium loss. In this study, coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride ions. Under the conditions of pH 0.8, di-(2-ethylhexyl)phosphoric acid concentration of 20%, phase ratio of 1:2, and extraction time of 8 min, the vanadium extraction could reach 80.00%. The Fourier transform infrared and electrospray ionization results reveal that, despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction, the chloride ion does not enter the organic phase, indicating an intriguing phenomenon. Among Cl−–V, SO42−–V, and H2O–V, the V–Cl bond is longer and the potential difference between coordinate ions and vanadium is smaller. Therefore, VO2+ gets easily desorbed with chloride ions and enter the organic phase. At the same time, the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily, which reduces the pH required for the extraction reaction.

关键词： vanadium     black shale     solvent extraction     high acidity extraction    

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Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 503-509 doi: 10.1007/s11783-013-0540-1

摘要： A mathematical model for the transport of Ce(IV) from hydrochloric acid solutions through dispersion flat combined liquid membrane (DFCLM) with contain 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (P507) as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick’s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce(IV) and the carrier to take place only at the solvent–aqueous interfaces. Model concentration profiles are obtained for the Ce(IV), from which extraction velocities are predicted. The experimental and simulated Ce(IV) extractions showed similar tendencies for a high Ce(IV) concentration and acidity case.The model results indicate that high initial Ce(IV) concentrations and acidity both have detrimental effects on Ce(IV) extraction and stripping. The diffusion coefficient of Ce(IV) in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10 m ·s and 31.2 μm, respectively. The results are in good agreement with experimental results.

关键词： Dispersion flat combined liquid membrane (DFCLM)     dispersion phase     feed phase     2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester     Ce (IV)    

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Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei Wang

《医学前沿（英文）》 2021年 第15卷 第1期   页码 79-90 doi: 10.1007/s11684-020-0783-8

摘要： Natural killer (NK) cells, a type of cytotoxic lymphocytes, can infiltrate into ischemic brain and exacerbate neuronal cell death. Astragaloside IV (ASIV) is the major bioactive ingredient of , a Chinese herbal medicine, and possesses potent immunomodulatory and neuroprotective properties. This study investigated the effects of ASIV on post-ischemic brain infiltration and activation of NK cells. ASIV reduced brain infarction and alleviated functional deficits in MCAO rats, and these beneficial effects persisted for at least 7 days. Abundant NK cells infiltrated into the ischemic hemisphere on day 1 after brain ischemia, and this infiltration was suppressed by ASIV. Strikingly, ASIV reversed NK cell deficiency in the spleen and blood after brain ischemia. ASIV inhibited astrocyte-derived CCL2 upregulation and reduced CCR2 NK cell levels in the ischemic brain. Meanwhile, ASIV attenuated NK cell activating receptor NKG2D levels and reduced interferon-γ production. ASIV restored acetylation of histone H3 and the p65 subunit of nuclear factor-κB in the ischemic brain, suggesting inhibition of histone deacetylase (HDAC). Simultaneously, ASIV prevented p65 nuclear translocation. The effects of ASIV on reducing CCL2 production, restoring acetylated p65 levels and preventing p65 nuclear translocation were mimicked by valproate, an HDAC inhibitor, in astrocytes subjected to oxygen-glucose deprivation. Our findings suggest that ASIV inhibits post-ischemic NK cell brain infiltration and activation and reverses NK cell deficiency in the periphery, which together contribute to the beneficial effects of ASIV against brain ischemia. Furthermore, ASIV’s effects on suppressing NK cell brain infiltration and activation may involve HDAC inhibition.

关键词： astragaloside IV     brain ischemia     natural killer cells     histone deacetylase     nuclear factor-κB    

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Visible light induces bacteria to produce superoxide for manganese oxidation

《环境科学与工程前沿（英文）》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1619-y

摘要：

● Term of manganese-oxidizing microorganisms should be reconsidered.

关键词： Mn(II) oxidation     Manganese-oxidizing bacteria     Reactive oxygen species     Mn(III/IV) oxides    

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Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

《结构与土木工程前沿（英文）》 2013年 第7卷 第1期   页码 72-82 doi: 10.1007/s11709-013-0185-y

摘要： A support vector machine (SVM) model has been developed for the prediction of liquefaction susceptibility as a classification problem, which is an imperative task in earthquake engineering. This paper examines the potential of SVM model in prediction of liquefaction using actual field cone penetration test (CPT) data from the 1999 Chi-Chi, Taiwan earthquake. The SVM, a novel learning machine based on statistical theory, uses structural risk minimization (SRM) induction principle to minimize the error. Using cone resistance ( ) and cyclic stress ratio ( ), model has been developed for prediction of liquefaction using SVM. Further an attempt has been made to simplify the model, requiring only two parameters ( and maximum horizontal acceleration ), for prediction of liquefaction. Further, developed SVM model has been applied to different case histories available globally and the results obtained confirm the capability of SVM model. For Chi-Chi earthquake, the model predicts with accuracy of 100%, and in the case of global data, SVM model predicts with accuracy of 89%. The effect of capacity factor ( ) on number of support vector and model accuracy has also been investigated. The study shows that SVM can be used as a practical tool for prediction of liquefaction potential, based on field CPT data.

关键词： earthquake     cone penetration test     liquefaction     support vector machine (SVM)     prediction    

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A modified neural learning algorithm for online rotor resistance estimation in vector controlled induction

A. CHITRA,S. HIMAVATHI

《能源前沿（英文）》 2015年 第9卷 第1期   页码 22-30 doi: 10.1007/s11708-014-0339-1

摘要： Online estimation of rotor resistance is essential for high performance vector controlled drives. In this paper, a novel modified neural algorithm has been identified for the online estimation of rotor resistance. Neural based estimators are now receiving active consideration as they have a number of advantages over conventional techniques. The training algorithm of the neural network determines its learning speed, stability, weight convergence, accuracy of estimation, speed of tracking and ease of implementation. In this paper, the neural estimator has been studied with conventional and proposed learning algorithms. The sensitivity of the rotor resistance change has been tested for a wide range of variation from -50% to+50% on the stability of the drive system with and without estimator. It is quiet appealing to settle with optimal estimation time and error for the viable realization. The study is conducted extensively for estimation and tracking. The proposed learning algorithm is found to exhibit good estimation and tracking capabilities. Besides, it reduces computational complexity and, hence, more feasible for practical digital implementation.

关键词： neural networks     back propagation (BP)     rotor resistance estimators     vector control     induction motor    

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Unconfined compressive strength prediction of soils stabilized using artificial neural networks and support vector

Alireza TABARSA, Nima LATIFI, Abdolreza OSOULI, Younes BAGHERI

《结构与土木工程前沿（英文）》 2021年 第15卷 第2期   页码 520-536 doi: 10.1007/s11709-021-0689-9

摘要： This study aims to improve the unconfined compressive strength of soils using additives as well as by predicting the strength behavior of stabilized soils using two artificial-intelligence-based models. The soils used in this study are stabilized using various combinations of cement, lime, and rice husk ash. To predict the results of unconfined compressive strength tests conducted on soils, a comprehensive laboratory dataset comprising 137 soil specimens treated with different combinations of cement, lime, and rice husk ash is used. Two artificial-intelligence-based models including artificial neural networks and support vector machines are used comparatively to predict the strength characteristics of soils treated with cement, lime, and rice husk ash under different conditions. The suggested models predicted the unconfined compressive strength of soils accurately and can be introduced as reliable predictive models in geotechnical engineering. This study demonstrates the better performance of support vector machines in predicting the strength of the investigated soils compared with artificial neural networks. The type of kernel function used in support vector machine models contributed positively to the performance of the proposed models. Moreover, based on sensitivity analysis results, it is discovered that cement and lime contents impose more prominent effects on the unconfined compressive strength values of the investigated soils compared with the other parameters.

关键词： unconfined compressive strength     artificial neural network     support vector machine     predictive models     regression    

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基于HHT的泄流结构损伤在线监测方法研究

练继建,李成业,刘昉,马斌

《中国工程科学》 2011年 第13卷 第12期   页码 38-44

摘要：

结合HHT方法在描述信号瞬时特性和信号处理方面的独特优势，提出了一种基于HHT的泄流结构损伤实时监测诊断方法。首先，利用信号能量谱构造能量分布向量ηi，进而定义结构异常指标和预警指数，最后通过计算相邻时间段内的异常指标，实现结构损伤的在线监测。应用文中方法对一导墙结构进行数值仿真试验，结果表明，文章中定义的异常指标能够较准确地判断结构的损伤，同时具有一定的抗噪能力。

关键词： 泄流结构     HHT     能量分布向量     异常指标     预警指数     数值仿真    

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Efficiency of scalar and vector intensity measures for seismic slope displacements

Gang WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第1期   页码 44-52 doi: 10.1007/s11709-012-0138-x

摘要： Ground motion intensity measures are usually used to predict the earthquake-induced displacements in earth dams, soil slopes and soil structures. In this study, the efficiency of various single ground motion intensity measures (scalar ) or a combination of them (vector ) are investigated using the PEER-NGA strong motion database and an equivalent-linear sliding-mass model. Although no single intensity measure is efficient enough for all slope conditions, the spectral acceleration at 1.5 times of the initial slope period and Arias intensity of the input motion are found to be the most efficient scalar for flexible slopes and stiff slopes respectively. Vector can incorporate different characteristics of the ground motion and thus significantly improve the efficiency over a wide range of slope conditions. Among various vector considered, the spectral accelerations at multiple spectral periods achieve high efficiency for a wide range of slope conditions. This study provides useful guidance to the development of more efficient empirical prediction models as well as the ground motion selection criteria for time domain analysis of seismic slope displacements.

关键词： seismic slope displacements     intensity measures     empirical prediction    

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Construction and identification of lentiviral RNA interference vector of rat leptin receptor gene

Zhengjuan LIU, Jie BIAN, Yuchuan WANG, Yongli ZHAO, Dong YAN, Xiaoxia WANG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 57-60 doi: 10.1007/s11684-009-0003-z

摘要： Leptin resistance is a main mechanism of acquired childhood obesity, and the suppression of long form of leptin receptor (OBRb) gene expression in diet-induced obese rats indicates that the down-regulation of OBRb gene expression plays a pivotal role in the mechanism of leptin resistance. The aim of the present study was to construct the lentiviral RNA interference (RNAi) vector of rat OBRb gene and evaluate the effects of siRNA on silencing OBRb gene expression. The target sequence of siRNA-OBRb was designed, and the complementary DNA containing both sense and antisense oligonucleotides was synthesized. After phosphorylation and annealing, these double-stranded DNA was cloned to pRNA-lentivector-VGFP to construct pRNA-Lenti-OBRb-VGFP recombinants with U6-containing promoter, target sequence and Poly III terminator. Then, the products were confirmed by electrophoresis and sequencing analysis, and the effects of RNAi on reducing gene expression were further confirmed by real-time polymerase chain reaction in transfected rat glioma cells expressing OBRb. The target sequence of siRNA-OBRb was successfully cloned to pRNA-lentivector-VGFP, and the RNAi protocol specifically reduced the expression of OBRb mRNA by approximately 80% compared with controls in transfected rat glioma cells. The successful construction of rat lentivirus vectors expressing OBRb-specific shRNA may be useful for further investigation .

关键词： receptors     leptin     RNA interference     lentivirus vector    

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Construction of a universal recombinant expression vector that regulates the expression of human lysozyme

Shen LIU, Shengzhe SHANG, Xuezhen YANG, Huihua ZHANG, Dan LU, Ning LI

《农业科学与工程前沿（英文）》 2018年 第5卷 第3期   页码 382-389 doi: 10.15302/J-FASE-2018211

摘要：

The mammary gland provides a novel method for producing recombinant proteins in milk of transgenic animals. A key component in the technology is the construction of an efficient milk expression vector. Here, we established a simple method to construct a milk expression vector, by a combination of homologous recombination and digestion-ligation. Our methodology is expected to have the advantages of both plasmid and bacterial artificial chromosome (BAC) vectors. The BAC of mouse whey acidic protein gene (mWAP) was modified twice by homologous recombination to produce a universal expression vector, and the human lysozyme gene (hLZ) was then inserted into the vector by a digestion-ligation method. The final vector containing the 8.5 kb mWAP 5′ promoter, 4.8 kb hLZ genomic DNA, and 8.0 kb mWAP 3′ genomic DNA was microinjected into pronuclei of fertilized mouse embryos, to successfully generate two transgenic mouse lines that expressed recombinant human lysozyme (rhLZ) in milk. The highest expression level of rhLZ was 0.45 g·L−1, and rhLZ exhibited the same antibacterial activity as native hLZ. Our results have provided a simple approach to construct a universal milk expression vector, and demonstrated that the resulting vector regulates the expression of hLZ in milk.

关键词： BAC recombinant methods     gene expression     human lysozyme     transgenic mice     milk expression vector    

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bentonite/sepiolite plastic concrete compressive strength using artificial neural network and support vector

Ali Reza GHANIZADEH, Hakime ABBASLOU, Amir Tavana AMLASHI, Pourya ALIDOUST

《结构与土木工程前沿（英文）》 2019年 第13卷 第1期   页码 215-239 doi: 10.1007/s11709-018-0489-z

摘要： Plastic concrete is an engineering material, which is commonly used for construction of cut-off walls to prevent water seepage under the dam. This paper aims to explore two machine learning algorithms including artificial neural network (ANN) and support vector machine (SVM) to predict the compressive strength of bentonite/sepiolite plastic concretes. For this purpose, two unique sets of 72 data for compressive strength of bentonite and sepiolite plastic concrete samples (totally 144 data) were prepared by conducting an experimental study. The results confirm the ability of ANN and SVM models in prediction processes. Also, Sensitivity analysis of the best obtained model indicated that cement and silty clay have the maximum and minimum influences on the compressive strength, respectively. In addition, investigation of the effect of measurement error of input variables showed that change in the sand content (amount) and curing time will have the maximum and minimum effects on the output mean absolute percent error (MAPE) of model, respectively. Finally, the influence of different variables on the plastic concrete compressive strength values was evaluated by conducting parametric studies.

关键词： bentonite/sepiolite plastic concrete     compressive strength     artificial neural network     support vector machine     parametric analysis    

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Diagnosis of sewer pipe defects on image recognition of multi-features and support vector machine in

Xiangyang Ye, Jian’e Zuo, Ruohan Li, Yajiao Wang, Lili Gan, Zhonghan Yu, Xiaoqing Hu

《环境科学与工程前沿（英文）》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1102-y

摘要：

An image-recognition-based diagnosis system of pipe defect types was established.

1043 practical pipe images were gathered by CCTV robot in a southern Chinese city.

The overall accuracy of the system is 84% and the highest accuracy is 99.3%.

The accuracy shows positive correlation to the number of training samples.

关键词： Sewer pipe defects     Defect diagnosing     Image recognition     Multi-features extraction     Support vector machine    

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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

Comparison of optimal capacitor placement methods in radial distribution system with load growth and ZIP load model

Veera Venkata Satya Naryana MURTY, Ashwani KUMAR

期刊论文

Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

期刊论文

Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

期刊论文

Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei Wang

期刊论文

Visible light induces bacteria to produce superoxide for manganese oxidation

期刊论文

Liquefaction prediction using support vector machine model based on cone penetration data

Pijush SAMUI

期刊论文

A modified neural learning algorithm for online rotor resistance estimation in vector controlled induction

A. CHITRA,S. HIMAVATHI

期刊论文

Unconfined compressive strength prediction of soils stabilized using artificial neural networks and support vector

Alireza TABARSA, Nima LATIFI, Abdolreza OSOULI, Younes BAGHERI

期刊论文

基于HHT的泄流结构损伤在线监测方法研究

练继建,李成业,刘昉,马斌

期刊论文

Efficiency of scalar and vector intensity measures for seismic slope displacements

Gang WANG

期刊论文

Construction and identification of lentiviral RNA interference vector of rat leptin receptor gene

Zhengjuan LIU, Jie BIAN, Yuchuan WANG, Yongli ZHAO, Dong YAN, Xiaoxia WANG

期刊论文

Construction of a universal recombinant expression vector that regulates the expression of human lysozyme

Shen LIU, Shengzhe SHANG, Xuezhen YANG, Huihua ZHANG, Dan LU, Ning LI

期刊论文

bentonite/sepiolite plastic concrete compressive strength using artificial neural network and support vector

Ali Reza GHANIZADEH, Hakime ABBASLOU, Amir Tavana AMLASHI, Pourya ALIDOUST

期刊论文

Diagnosis of sewer pipe defects on image recognition of multi-features and support vector machine in

Xiangyang Ye, Jian’e Zuo, Ruohan Li, Yajiao Wang, Lili Gan, Zhonghan Yu, Xiaoqing Hu

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