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Influence of ageing on oil degradation and gassing tendency under high-energy electrical discharge faults for mineral oil and synthetic ester

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High Voltage 2020年第6期5卷 731-738页

作者： L.Loiselle U.Mohan rao I.Fofana Research Chair on the Aging of Power Network Infrastructure(ViAHT) Universitédu QuébecàChicoutimiChicoutimiQCG7H 2B1Canada

In this work, mineral oil and synthetic esters were selected at different ageing factors (based on acidity values). Fresh and aged oils have been subjected to high-energy discharges (repeated 100 breakdowns) to simulate electric faults of highly vulnerable intensity. The intent of this work is to understand the influence of high-energy electric faults on oil degradation and gassing tendency at different ageing conditions. In this study, the influence of the high-energy discharges on degradation and gassing tendency at different ageing factors is reported for mineral oil and synthetic esters. Oil degradation is reported by adopting ultraviolet spectroscopy, turbidity and particle counter as per american society for testing and materials (ASTM) standard test methods. Gassing tendencies and fault gas analysis are understood by dissolved the gas analysis using Duval's triangle and Duval's pentagon methods for mineral and non-mineral oils. It is found that the influence of high-energy discharges on oil degradation is higher in mineral oils to that of the synthetic esters. The intensity of the gassing tendency is higher for ester fluids;however, as per the Duval methods, the faulty conditions are at lower levels as compared to mineral oils.

关键词： synthetic energy high

Temperature-controlled mode selection of Er-doped random fiber laser with disordered bragg gratings

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Photonics Research 2016年第3期4卷 102-105页

作者： W.L.Zhang Y.b.Song X.P.Zeng R.Ma Z.J.Yang Y.J.rao Key Laboratory of Optical Fiber Sensing & Communications (Education Ministry of China) University of Electronic Science & Technology of China

In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber bragg grating(FbG) array, as well as to control the lasing mode of the RFL by heating specific locations of the disordered FbG array. The disordered FbG array performs as both the gain medium and random distributed reflectors, which together with a tunable point reflector form the RFL. Coherent multi-mode random lasing is obtained with a threshold of between 7.5 and 10 mW and a power efficiency between 23% and 27% when the reflectivity of the point reflector changes from 4% to 50%. To control the lasing mode of random emission, a specific point of the disordered FbG array is heated so as to shift the wavelength of the FbG(s) at this point away from the other ***, different resonance cavities are formed, and the lasing mode can be controlled by changing the location of the heating point.

关键词： mode Temperature-controlled mode selection of Er-doped random fiber laser with disordered bragg gratings

A Virtual TDOA Localization Scheme of Chinese DTMb Signal in Radio Monitoring Networks

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China Communications 2015年第11期12卷 164-176页

作者： LIU Shang rao Menglou TAO Yunzheng LIU Long ZHANG Ping Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute (WTI)Beijing University of Posts and Telecommunications

As the radio communications technology widely used,wireless location technology plays a more important role in maintaining the order of the air *** concretely effective symbol calibration method with regard to Chinese DTMb signal of different frame mode is quite under research due to the multiple structure of DTMb *** this paper,we propose a Time Difference of Arrival(TDOA)-based passive location scheme using least square *** the large number of anchor nodes in wireless monitoring network,a novel algorithm is formulated to solve the None-LineOf-Sight *** derived Cramer rao Lower bound of the localization method guides to the accuracy of the position outcome with regards to the calibration *** contrast with traditional multi-terminal location schemes,our location scheme can reduce calculation complexity and location costs abruptly.A twostep NLOS identification algorithm is *** simulation is employed to verify the well performance of the calibration method of3-4 db superiority than normal method and also the whole localization scheme for less than 50 meters through channel of SNR lower than *** also shows that our algorithm can effectively identify NLOS path and improve positioning accuracy.

关键词： Radio Monitoring White Space Chinese DTMb Signal Localization

Evaluating Value of Natural Landscapes in China

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Chinese Geographical Science 2016年第2期26卷 244-255页

作者： XIAO Yi CHENG Cheng YANG Wu OUYANG Zhiyun rao Enming State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Conservation International 2011 Crystal Drive Suite 500 Arlington VA 22202 USA

Natural landscapes consist of the natural substances, environment, and phenomena, all of which provide many benefits to people, including a sense of place, sightseeing, relaxing, and recuperating. However, the economic value of natural landscapes has only been recognized in recent decades, and the resulting large-scale decline and degradation of ecosystems now severely threatens the sustainable provision of their services to society. There is an emerging consensus that natural capital should be incorporated into the current socioeconomic accounting system. Many studies valuated natural resources at local and regional scales, but there are very few empirical studies at a national level. To provide a benchmark for natural landscape management on a national scale, we use the travel cost method(TCM) and the contingent valuation method(CVM) to determine the economic value and the spatial distribution of natural landscapes across China. Our results show that the total economic value of China′s natural landscape was 9.75 × 10^(11) U.S. dollars(USD) in 2012. Of this value, the highest proportion was in the eastern and southwestern regions of China, which accounts for 23.7% and 18.3%, respectively. The provinces of Guangdong, Sichuan, Yunnan, Inner Mongolia, and Heilongjiang were the top five in terms of the largest number of natural landscapes and largest economic values. Together, these five provinces accounted for 32.9% of the total number of natural landscapes and 29.4% of the total economic value in 2012. We believe this study will increase awareness of the value of natural landscapes, and more importantly provide a scientific basis for resolving conflicts between development and resource conservation.

关键词： travel cost method(TCM) contingent valuation method(CVM) natural landscape value China

Modelling reference evapotranspiration using gene expression programming and artificial neural network at Pantnagar,India

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Information Processing in Agriculture 2023年第4期10卷 547-563页

作者： Pangam Heramb Pramod Kumar Singh K.V.Ramana rao A.Subeesh Division of Irrigation and Drainage Engineering ICAR-Central Institute of Agricultural EngineeringBhopal 462038India Department of Irrigation and Drainage Engineering G.B.Pant University of Agriculture and TechnologyPantnagar 263145India Division of Agricultural Mechanization ICAR-Central Institute of Agricultural EngineeringBhopal 462038India

Evapotranspiration is an essential component of the hydrological cycle that is of particular interest for water resource *** quantification is helpful in irrigation scheduling,water balance studies,water allocation,*** of reference evapotranspiration(ET0)using both gene expression programming(GEP)and artificial neural network(ANN)techniques was done using the daily meteorological data of the Pantnagar region,India,from 2010 to 2019.A total of 15 combinations of inputs were used in developing the ET0 *** model with the least number of inputs consisted of maximum and minimum air temperatures,whereas the model with the highest number of inputs consisted of maximum air temperature,minimum air temperature,mean relative humidity,number of sunshine hours,wind speed at 2mheight and extra-terrestrial radiation as inputs and with ET0 as the output for all the *** the GEP models were developed for a single functional set and pre-defined genetic operator values,while the best structure in each ANN model was found based on the performance during the testing *** was found that ANN models were superior to GEP models for the estimation *** was evident from the reduction in RMSE values ranging from 2%to 56%during training and testing phases in all the ANN models compared with GEP *** ANN models showed an increase of about 0.96%to 9.72%of R2 value compared to the respective GEP *** comparative study of these models with multiple linear regression(MLR)depicted that the ANN and GEP models were superior to MLR models.

关键词： Artificial Neural Networks Evolutionary algorithms Gene Expression Programming Machine Learning Regression Analysis Reference evapotranspiration models

Monoclonal Gammopathy of Renal Significance(MGRS): Prospects for Treatment in Integrated Chinese and Western Medicine

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Chinese Journal of Integrative Medicine 2021年第9期27卷 643-648页

作者： LI Jin-pu DU Ya-ting LI Shen rao Xiang-rong Department of Nephrology Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing(100053)China

Monoclonal gammopathy of renal significance(MGRS)is a pathological state which presents with a spectrum of renal *** is characterized by pathogenic monoclonal immunoglobulins or light chains produced by a premalignant plasma cell or b cell *** view of inadequate understanding in the past,the low detection rate of MGRS often results in poor outcomes and reduces quality of life of ***,MGRS stands for a group of clinical refractory renal *** date,no standard treatment strategy for MGRS is *** consensus suggests a clone-directed approach that aims to eradicate the offending clone,but its long-term prognosis is not *** this article,we discuss the diagnostic methods,highlight treatment advances,and introduce integrated Chinese and Western medicine in the management of MGRS.

关键词： monoclonal gammopathy of renal significance Chinese medicine integrative medicine

Simulation Study on Constraining Gravitational Wave Propagation Speed by Gravitational Wave and Gamma-ray burst Joint Observation on binary Neutron Star Mergers

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Research in Astronomy and Astrophysics 2024年第8期24卷 42-51页

作者： Jin-Hui rao Shu-Xu Yi Lian Tao Qing-Wen Tang Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Theories of modified gravity suggest that the propagation speed of gravitational waves(GW)v_gmay deviate from the speed of light c.A constraint can be placed on the difference between c and v_gwith a simple method that uses the arrival time delay between GW and electromagnetic wave simultaneously emitted from a burst *** simulated the joint observation of GW and short gamma-ray burst signals from binary neutron star merger events in different observation campaigns,involving advanced LIGO(aLIGO)in design sensitivity and Einstein Telescope(ET)joint-detected with Fermi/*** a result,the relative precision of constraint on v_gcan reach~10~(-17)(aLIGO)and~10^(-18)(ET),which are one and two orders of magnitude better than that from GW170817,*** continue to obtain the bound of graviton mass m_g≤7.1(3.2)×10~(-20)eV with aLIGO(ET).Applying the Standard-Model Extension test framework,the constraint on v_gallows us to study the Lorentz violation in the nondispersive,nonbirefringent limit of the gravitational *** obtain the constraints of the dimensionless isotropic coefficients S_(00)^(4)at mass dimension d=4,which are-1×10^(-15)

关键词： gravitational waves-(stars)gamma-ray burst general-stars neutron

Analysis of vibrational spectra of nano-bio molecules: Application to metalloporphrins

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Chinese Physics b 2013年第9期22卷 225-232页

作者： K Srinivasa rao G Srinivas J.Vijayasekhar V.U.M.rao Y.Srinivas K.Sunil babu V.Sunndadara Siva Kumar A.Hanumaiah Department of Electronics & Instrumentation Engineering Lakireddy Bali Reddy College of Engineering Department of Physics KL University Research Scholar Department of MathematicsJawaharlal Nehru Technological University Department of Applied Mathematics College of Science & TechnologyAndhra University Department of Computer Science GITAM University Department of Physics Miracle Engineering College Department of Electronics & Instrumentation Rajeev Gandhi Memorial Engineering College Department of Physics Lara's Vignan Institute of Technology and Science

In this paper, we have applied the Lie algebraic model to nano-bio molecules to determine the vibrational spectra of different stretching and bending vibrational modes. The determined vibrational energy levels by the Lie algebraic model are compared with the experimental data. The results from the theoretical mode[ are consistent with the experimental data. The vibrational energy levels are clustering in the excited states.

关键词： Lie algebraic model vibrational spectra vibrational modes metalloporphyrins

Evolution of quantum states via Weyl expansion in dissipative channel

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Chinese Physics b 2019年第8期28卷 160-166页

作者： Li-Yun Hu Zhi-Ming rao Qing-Qiang Kuang Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China Key Laboratory of Optoelectronic and Telecommunication Jiangxi Normal UniversityNanchang 330022China

based on the Weyl expansion representation of Wigner operator and its invariant property under similar transformation,we derived the relationship between input state and output state after a unitary transformation including Wigner function and density *** is shown that they can be related by a transformation matrix corresponding to the unitary *** addition,for any density operator going through a dissipative channel,the evolution formula of the Wigner function is also *** applications,we considered further the two-mode squeezed vacuum as inputs,and obtained the resulted Wigner function and density operator within normal ordering *** method is clear and concise,and can be easily extended to deal with other problems involved in quantum metrology,steering,and quantum information with continuous variable.

关键词： Weyl expansion Wigner operator similar transformation two-mode squeezed state integration within ordered product(IWOP)technique