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Twisted Pair Cable Fault Diagnosis via Random Forest Machine Learning

Computers, Materials & Continua 2022年第6期71卷 5427-5440页

作者： n.b.Ghazali F.C.Seman k.Isa k.n.Ramli Z.Z.Abidin S.M.Mustam M.A.Haek A.n.Z.Abidin A.Asrokin Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn MalaysiaBatu PahatJohor TM Research&Development CyberjayaMalaysia

Applying the fault diagnosis techniques to twisted pair copper cable is beneficial to improve the stability and reliability of internet access in Digital Subscriber Line(DSL)Access network *** network performance depends on the occurrence of cable fault along the copper ***,most of the telecommunication providers monitor the network performance degradation hence troubleshoot the present of the fault by using commercial test gear on-site,which may be resolved using data analytics and machine learning *** paper presents a fault diagnosis method for twisted pair cable fault detection based on knowledge-based and data-driven machine learning *** DSL Access network is emulated in the laboratory to accommodate VDSL2 Technology with various types of cable fault along the cable distance between 100 m to 1200 ***,the line operation parameters and loop line testing parameters are collected and used to ***,the feature transformation,a knowledge-based method,is utilized to pre-process the fault ***,the random forests algorithms(RFs),a data-driven method,are adopted to train the fault diagnosis classifier and regression algorithm with the processed fault ***,the proposed fault diagnosis method is used to detect and locate the cable fault in the DSL Access network *** results show that the cable fault detection has an accuracy of more than 97%,with less minimum absolute error in cable fault localization of less than 11%.The proposed algorithm may assist the telecommunication service provider to initiate automated cable faults identification and troubleshooting in the DSL Access network System.

关键词： Twisted pairs random forest machine learning cable fault DSL

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CCD互相关粒子图像测速及其在对抗流流场测量中的应用

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推进技术 2000年第6期21卷 83-88页

作者：郑日恒 bray k n C Rogg b Lecordier b 英国剑桥大学工程系鲁尔大学流体热力学研究所 CORIA Rouen大学

在常规自相关粒子图像测速 (PIV)系统的基础上 ,发展了一个采用CCD像机的互相关粒子图像测速系统。用这一新系统测量了对抗流流场的结果表明 ,这一技术克服了自相关粒子图像测速技术在测量具有滞止点的流场中的困难。实验说明 ,与自相... 详细信息

在常规自相关粒子图像测速 (PIV)系统的基础上 ,发展了一个采用CCD像机的互相关粒子图像测速系统。用这一新系统测量了对抗流流场的结果表明 ,这一技术克服了自相关粒子图像测速技术在测量具有滞止点的流场中的困难。实验说明 ,与自相关粒子图像测速技术相比。

关键词：粒子速度成像对抗流互相关自相关速度分布流动测量

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Seasonal variability of ambient nH_3, nO, nO_2 and SO_2 over Delhi

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Journal of Environmental Sciences 2010年第7期22卷 1023-1028页

作者： S.k.Sharma A.Datta T.Saud M.Saxena T.k.Mandal Y.n.Ahammed b.C.Arya Radio and Atmospheric Sciences Division National Physical Laboratory Council of Scientific and Industrial Research (CSIR)

We present the diurnal and seasonal variability of ambient nH3, nO, nO2 and SO2 over Delhi, India. Ambient nH3, nO and nO2 were measured continuously during winter, summer and autumn seasons using nH3- and nOx-analyzer, which operates by chemiluminescence method with a higher estimation efficiency （〉 90%） than the chemical trap method （reproducibility 4.7%）. Prominent diurnal, day-to-day and seasonal variations of ambient mixing ratio of nH3, nO, nO2 and SO2 were observed during the study period. Seasonal variation with higher mixing ratio in winter was observed for all measured trace gases except nO. Day-night variation of all measured trace gases observed was higher in winter in comparison with summer. Late morning increase in nO2 mixing ratio might be attributed to conversion of nO to nO2 with the interaction ofO3.

关键词： ambient nH3, diurnal and seasonal variations chemiluminescence method ambient nO, nO2 and SO2

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Potential application of graphene oxide and Aspergillus niger spores with high adsorption capacity for recovery of europium from red phosphor,compact fluorescent lamp and simulated radioactive waste

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Journal of Rare Earths 2023年第1期41卷 157-166页

作者： b.Arunraj Vidya Rajesh n.Rajesh Department of Chemistry Birla Institute of Technology and Science-PilaniHyderabad CampusShameerpetHyderabad 500078India Department of biological Sciences Birla Insttute of Technology and Science-PilaniHyderabad CampusShameerpetHyderabad 500078India

The recovery of rare earth elements(REEs) is a global challenge and the mining of rare earths has serious environmental implications due to the toxic waste released post ***,the rising demand for rare earths and their far reaching electronic applications necessitates an effective strategy to recover the REEs from more viable *** this work,the graphene oxide-Aspergillus niger spores(*** spores) blend was utilized for adsorptive recovery of a precious rare earth Eu(Ⅲ) and the adsorption variables like pH of the medium,adsorbent dosage,sorption kinetics,thermodynamics,and isotherm were optimized for the developed bioso *** adsorption process suits the Langmuir isotherm model with a maximum adsorption capacity of 147.3 mg/*** pseudo-second-order kinetics is a perfect fit to describe the adsorption *** results obtained through the Van’t Hoff plot show negative free energy change(ΔG^(0)) which implies the spontaneity of the adsorption *** negative standard enthalpy change(ΔH^(0)) values show that the nature of the adsorption process is *** analytical characterizations including Fourier transform infrared spectroscopy(FTIR),Raman,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),brunauer-Emmett-Teller(bET),thermal gravimetric analysis(TGA),and scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDX) were employed to study the *** features of *** spores biosorbent were applied to recover Eu(Ⅲ) from real samples such as fluorescent lamp phosphor,red phosphor powder,and a simulated radioactive waste solution.

关键词： Europium Graphene oxide Aspergillus niger Phosphor Radioactive waste Rare earths

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Approximate analytical solutions and mean energies of stationary Schrodinger equation for general molecular potential

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Chinese Physics b 2021年第7期30卷 116-131页

作者： Eyube E S Rawen b O Ibrahim n Department of Physics School of Physical SciencesModibbo Adama University of TechnologyP M B 2076 YolaAdamawa StateNigeria Directorate of basic and Remedial Studies Abubakar Tafawa Balewa University(ATBU)P M B 750001BauchiBauchi StateNigeria Department of Physics Faculty of ScienceP M B 1069MaiduguriBorno StateNigeria

The Schrodinger equation is solved with general molecular potential via the improved quantization *** for bound state energy eigenvalues,radial eigenfunctions,mean kinetic energy,and potential energy are obtained in compact *** modeling the centrifugal term of the effective potential,a Pekeris-like approximation scheme is ***,we use the Hellmann–Feynman theorem to derive the relation for expectation *** state energy eigenvalues,wave functions and meanenergies of Woods–Saxon potential,Morse potential,Mobius squared and Tietz–Hua oscillators are deduced from the general molecular *** addition,we use our equations to compute the bound state energy eigenvalues and expectation values for four diatomic molecules viz.H_(2),CO,HF,and O_(2).Results obtained are in perfect agreement with the data available from the literature for the potentials and *** also show that as the vibrational quantum number increases,the mean kinetic energy for the system in a Tietz–Hua potential increases slowly to a threshold value and then *** in a Morse potential,the mean kinetic energy increases linearly with vibrational quantum number increasing.

关键词： general molecular potential Schrodinger equation improved quantization rule

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Assessment of deterioration in RHA-concrete due to magnesium sulphate attack

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 691-696页

作者： G.A. Habeeb H.b. Mahmud n.b.A.A. Hamid Department of Civil Engineering Faculty of Engineering University of Malaya

The assessment of magnesium sulphate attack on concretes containing rice husk ash （RHA, 20wt% of the cementitious materials） with various average particle sizes was investigated. The total cementitious materials were 390 kg and the water-to-binder ratio （W/b） was 0.53 for all mixtures. Specimens were initially cured in water for 7 d and then immersed in the 3wt% magnesium sulphate solution for up to 111 d of exposure. The specimens were subjected to drying-wetting cycles to accelerate sulphate attack. In addition to the visual monitoring of the specimens, the concrete specimens were subsequently tested for compressive strength, dynamic modulus of elasticity, and length and mass changes. The results show that the specimens exposed to sulphate attack exhibit higher strength and dynamic modulus than those kept in water. The length change is negligible and can be attributed to the normal swelling of concrete. On the other hand, concretes suffers mass loss and surface spalling and softening; the fine RHA-concrete results in a better resistance. For the accelerated sulphate attack method used in this study, mass change and visual monitoring are recommended for assessing the deterioration degree and the effectiveness of supplementary cementitious materials to resist sulphate attack.

关键词： concretes pozzolan ettringite rice husk ash (RHA) magnesium sulphate

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blue emitting exciplex for yellow and white organic light‑emitting diodes

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Frontiers of Optoelectronics 2023年第4期16卷 191-203页

作者： kavya Rajeev C.k.Vipin Anjali k.Sajeev Atul Shukla Sarah k.M.McGregor Shih‑Chun Lo Ebinazar b.namdas k.n.narayanan Unni Centre for Sustainable Energy Technologies CSIR-National Institute for Interdisciplinary Science and TechnologyThiruvananthapuram 695019India Academy of Scientifc and Innovative Research(AcSIR) Ghaziabad 201002India Centre for Organic Photonics&Electronics The University of QueenslandBrisbaneQLD 4072Australia School of Mathematics and Physics The University of QueenslandBrisbaneQLD 4072Australia School of Chemistry and Molecular biosciences The University of QueenslandBrisbaneQLD 4072Australia

White organic light-emitting diodes(WOLEDs)have several desirable features,but their commercialization is hindered by the poor stability of blue light emitters and high production costs due to complicated device ***,we investigate a standard blue emitting hole transporting material(HTM)n,n'-bis(naphthalen-1-yl)-n,n'-bis(phenyl)benzidine(nPb)and its exciplex emission upon combining with a suitable electron transporting material(ETM),3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ).blue and yellow OLEDs with simple device structures are developed by using a blend layer,nPb:TAZ,as a blue emitter as well as a host for yellow phosphorescent dopant iridium(III)bis(4-phenylthieno[3,2-c]pyridinato-n,C2')acetylacetonate(PO-01).Strategic device design then exploits the ambipolar charge transport properties of tetracene as a spacer layer to connect these blue and yellow emitting *** tetracene-linked device demonstrates more promising results compared to those using a conventional charge generation layer(CGL).Judicious choice of the spacer prevents exciton difusion from the blue emitter unit,yet facilitates charge carrier transport to the yellow emitter unit to enable additional exciplex *** complementary behavior of the spacer improves the blue emission properties concomitantly yielding reasonable yellow *** overall white light emission properties are enhanced,achieving CIE coordinates(0.36,0.39)and color temperature(4643 k)similar to *** intermolecular exciplex emission in OLEDs simplifes the device architecture via its dual functionality as a host and as an emitter.

关键词： Organic light-emitting diodes Dual functional exciplex Spacers Device design strategy blue exciplex Yellow OLEDs White light emission

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Studies of two lanthanide coordination polymers built up from dinuclear units

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Journal of Rare Earths 2013年第1期31卷 85-93页

作者： b.benmerad k.Aliouane n.Rahahlia A.Guehria-Ladoudi S.Dahaoui C.Lecomte Laboratory of Crystallography and Thermodynamic Department of Chemistry Faculty of ScienceUniversity A. MIRABejaa CRM2 UMR-CNRS 7036Institut Jean BarriolUniversity Nancy I

The two three-dimensional oxo-bfidged lanthanides {[Ln2（C4H2O4）3（H20）4]· 3H2O}3, with Ln=Ho3＋（1）; Gd3＋（2）, are isomorphous. They have layer-type structures built up from non-centrosymrnetric dinuclear unit Ln2O12（H2O）4, beside three lattice H20 molecules stabilizing the 3D open-frmnework. The building entities are linked through one classical syn-anti g2-carboxylato-k1O：k^1O＇ bridge. Within the bi-polyhedra, two double μ2-O＇; k2O,O＇ bridges and a syn-syn classical one, support the magnetic measurements carried out on holmium compound indicating relatively weak anti-ferromagnetic interactions. The compari- son with magnetic studies on the almost similar reported Gd（III） compound, suggested that concomitant antiferromagnetic and ferro- magnetic properties could not be excluded. The two distinct thermal behaviors evidenced the higher metal-water bond strength with the smaller cation, and revealed the great supramolecular effects generated by hydrogen-bonding patterns.

关键词： lanthanide organic frameworks crystal structure thermal behavior magnetic interactions rare earths

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DnA-guided hepatitis b treatment,viral load is essential,but not sufficient

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World Journal of Gastroenterology 2009年第4期15卷 423-430页

作者： Rafael bárcena Marugán Silvia García Garzón Services of Liver-Gastroenterology Hospital Ramón y CajalUniversity of Alcalá Department of Gastroenterology Hospital Universitario de GuadalajaraUniversity of Alcalá

Hepatitis b virus （HbV） infection is a global public health problem that concerns 350 million people worldwide. Individuals with chronic hepatitis b （Crib） are at increased risk of developing liver cirrhosis, hepatic de-compensation and hepatocellular carcinoma. To maintain undetectable viral load reduces chronic infection complications. There is no treatment that eradicates HbV infection. Current drugs are expensive, are associated with adverse events, and are of limited efficacy. Current guidelines try to standardize the clinical practice. nevertheless, controversy remains about management of asymptomatic patients with Crib who are hepatitis b e antigen （HbeAg）-positive with normal alanine aminotransferase, and what is the cut-off value of viral load to distinguish HbeAg- negative Crib patients and inactive carriers. We discuss in detail why DnA level alone is not sufficient to begin treatment of Crib.

关键词： Hepatitis b virus Viral DnA Alaninetransaminase Antiviral drug Hepatitis b e antigen Antiviral drug resistance

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QTL Analysis for Grain Iron and Zinc Concentrations in Two O. nivara Derived backcross Populations

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Rice science 2018年第4期25卷 197-207页

作者： b. P. M. SWAMY k. kALADHAR1, k. AnURADHA Anil k. bATCHU T. LOnGVAH n. SARLA Indian Institute of Rice Research Rajendranagar Hyderabad 500030 India Plant breeding Division International Rice Research Institute DAPO Box 7777 Metro Manila the Philippines International Crops Research Institute on Semi Arid Tropics Patancheru Hyderabad 502324 India national Institute of nutrition Hyderabad 500007 India

Identification of quantitative trait loci （QTLs） for grain mineral elements can assist in faster and more precise development of micronutrient dense rice varieties through marker-assisted breeding. In the present study, QTLs were mapped for Fe and Zn concentrations in two bC2F3 mapping populations derived from the crosses of O. sativa cv Swarna with two different accessions of O. nivara. In all, 10 and 8 QTLs were identified for grain Fe and Zn concentrations in population 1, and 7 and 5 QTLs were identified in population 2, respectively. Eighty percent of the QTLs detected in both populations were derived from O. nivara. Five QTLs for Fe and three QTLs for Zn explained more than 15% phenotypic variance either in interval or composite interval mapping. The locations of O. nivara derived QTLs such as qFe2.1, qFe3.1, qFe8.2 and qZn12.1 were consistently identified in both the populations. Epistatic interaction was observed only between RM106 and RM6 on chromosome 2 and between RM22 and RM7 on chromosome 3 for Fe concentration in population 1. Sixteen candidate genes for metal homeostasis were found to co-locate with 10 QTLs for Fe and Zn concentrations in both the populations. Most of the Fe and Zn QTLs were found to co-locate with QTLs for grain yield and grain quality traits. Some of the major effect QTLs identified can be used to improve rice grain Fe and Zn concentrations.

关键词： biofortification micronutrient Fe concentration Zn concentration rice wild rice quantitative trait locus gene marker assisted breeding

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