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7th International Conference on Energy, Electrical and Power Engineering (CEEPE)

作者： Xu, Bin Liu, Ren Xu, Weining Wang, Shuai Teng, JiaJia Ye, Jiale China Three Gorges Univ Coll Elect Engn & New Energy Yichang Peoples R China Hubei Prov Engn Technol Res Ctr Power Transmiss L Yichang Peoples R China Three Gorges Elementary Sch Yichang Peoples R China

ISBN: (纸本)9798350375794;9798350375800

Dynamic line rating (DLR) holds significant importance in fully tapping transmission potential of overhead transmission line compared to static line rating (SLR). However, a single predictive model is insufficient to accurately capture the impact of meteorological elements such as wind speed and ambient temperature on the fluctuation and stochasticity of DLR. Therefore, the empirical mode decomposition algorithm is adopted to preprocess various meteorological data to reduce non-stationarity. Based on this, a point prediction model of DLR based on ensemble learning XGBoost is proposed. To account for the uncertainty of DLR, a mixed kernel density estimation algorithm is introduced to fit the probability distribution of DLR prediction errors, thereby achieving probabilistic prediction of DLR. Case studies demonstrate that the proposed method achieves superior predictive accuracy.

关键词： dynamic line rating forecasting transmission line probability distribution function ensemble learning

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MODELLING OF RAINFALL GENERATED RUNOFF AND SEDIMENT YIELD

MODELLING OF RAINFALL GENERATED RUNOFF AND SEDIMENT YIELD

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作者： PUSHPENDRA KUMAR SINGH Indian Institute of Technology Roorkee

学位级别：博士

Rainfall-runoff-sediment yield modeling is integral to water resources planning, development and management, flood control, environmental impact assessment, erosion and sediment control, water quality modeling and watershed management. A multitude of models are available in hydrologic literature to address the issues related with the runoff and sediment yield modeling. The Soil Conservation Service Curve Number (SCS-CN) method is one of the popular event-based models widely used for estimation of direct runoff for a given storm rainfall event from small watersheds. The method has witnessed myriad applications including those which were not originally intended. Similarly, the synthetic unit hydrograph (SUH) methods are widely used for estimating design flood for ungauged catchments, and for partial data availability conditions. The SUH methods are of paramount importance for developing countries, for majority of the small basins are ungauged. The sediment graph models are particularly used for estimation of time distributed sediment yield and play a significant role in water quality modeling and effectiveness of watershed management programmes. The increased awareness of environmental quality and an efficient control of non-point source pollution have further increased the need for sediment graph models. The present study is undertaken to explore the new/modified or improved versions of SCS-CN method, SUH methods, and sediment graph models on a more sound hydrological perception and a stronger mathematical foundation to perform their prescribed tasks successfully and efficiently. Revised Soil Moisture Accounting Procedure in SCS-CN Methodology Recent past has witnessed various improvements/modifications to the existing SCS- CN methodology. Based on certain issues, however, a need of further improvement has been felt for better results. The soil moisture accounting (SMA) procedure that lies behind the SCS-CN methodology is one of them. Introduced by Williams and LaSeu

关键词： SCS-CN method Soil moisture accounting Synthetic unit hydrograph probability distribution function Sediment graph Rainfall-runoff-sediment yield

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Loss Optimization of IEEE 12 Bus Radial distribution System Integration with Wind Weibull distribution function using PSO Technique 7

Loss Optimization of IEEE 12 Bus Radial Distribution System ...

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7th IEEE Power India International Conference (PIICON)

作者： Bansal, Ajay Kumar, Anil Kumar, Naresh Deen Bandhu Chhotu Ram Univ Sci & Technol Sonipat India

ISBN: (纸本)9781467389624

Due to increasing per capita energy consumption and exponential rising population, power system losses increasingly and reliability decreasing. The distributed generator can improve the power system reliability and reduce losses. The most widely preferred DG which is large attracted by large scale as wind powers do not have pollution issue and consider as clean energy source. By the wind to its maximum extent it is necessary to place the wind turbine at the place where the losses of the system and the size of the turbine are minimum. In this paper the PSO (particle swarm optimization) technique is applied on IEEE 12 radial standard bus system to get reduced losses and optimum size of wind turbine. Backward/forward sweep method used to analyze the power flow in radial distribution systems. Weibull functions F(x) have been used to describe the best wind distribution which is one of the probabilistic modeling to select random variable. From the results optimum size of turbine is obtained and also obtains the location for placement of wind turbine to optimum the system losses. MATLAB/Simulink is used to simulate the optimization of power losses at power output of mean various wind turbine speed.

关键词： Radial distributed system Backward/forward sweep method PSO probability distribution function

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Doppler spectral line shapes in low frequency turbulent plasmas

Doppler spectral line shapes in low frequency turbulent plas...

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9th International Workshop on Plasma Edge Theory in Fusion Devices

作者： Marandet, Y Capes, H Godbert-Mouret, L Koubiti, M Stamm, R Univ Aix Marseille 1 PIIM Ctr St Jerome F-13397 Marseille France CEA DRFC F-13108 St Paul Les Durance France

In this paper we investigate the influence of low frequency, i.e. drift wave like turbulence on the spectral line shapes in magnetized plasmas. The measured spectrum, which is obtained through both spatial and time averaging processes, is shown to contain information on turbulence. Using a statistical description of the turbulent fluctuations, we investigate the effects of density, fluid velocity and temperature fluctuations on the Doppler profile of a spectral line. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA. Weinheim.

关键词： spectroscopy line shapes plasma turbulence probability distribution function

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Channel Capacity of Different Adaptive Transmission Techniques over Log-Normal Shadowed Fading Environment 3

Channel Capacity of Different Adaptive Transmission Techniqu...

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3rd International Conference on Computing for Sustainable Global Development (INDIACom)

作者： Verma, P. K. Jain, Priyanka Soni, Sanjay Raw, R. S. Delhi Technol Univ Dept Elect & Commun Engn New Delhi India GB Pant Engn Coll Dept Elect & Commun Engn Pauri UK India Amhedkar Inst Adv Commun Technol & Res Dept Comp Sci & Engn New Delhi India

ISBN: (纸本)9789380544199

Channel capacity is an important parameter to analyses the performance of wireless communication. To model the shadowing effect of the wireless channel, lognormal distribution is widely used. In this paper, our aim to develop the closed-form expression of average channel capacity of slow fading channel categorized by the log-normal distribution. The channel capacity in closed form expression for four different adaptive transmission schemes such as optimal power and rate adaption, channel inversion with fixed rate optimal rate adaption and truncated channel inversion with fixed rate are derived using Holtzamn approximation. The channel capacity results are compared under light and heavy shadowing condition and some interesting observations are made.

关键词： Log-normal distribution probability distribution function Holtzman Approximation Channel Capacity Channel Side Information

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NLOS Detection and Mitigation in Differential Localization Topologies based on UWB Devices 9

NLOS Detection and Mitigation in Differential Localization T...

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9th International Conference on Indoor Positioning and Indoor Navigation (IPIN)

作者： Zandian, Reza Witkowski, Ulf South Westphalia Univ Appl Sci Dept Circuits Design & Elect Soest Germany

ISBN: (纸本)9781538656358

Ultra-wideband systems (UWB) are a common technology which is used for indoor localization applications due to its accuracy. However there are some challenges to implement these systems in indoor area with obstacles and barriers. One of the challenges is non-line of sight conditions (NLOS) between two communicating nodes which results in large localization error. Many techniques have been proposed in the literature for NLOS detection and mitigation but most of them are deployed in time of arrival (ToA) cases. This paper extends the NLOS detection and mitigation techniques to time difference of arrival cases (TDoA). The proposed method is a parametric technique based on the probability distribution function (PDF) of features collected from received signal characteristics. An innovative method is used to apply the parametric detection method on TDoA cases both in detection and mitigation stages. The mitigation technique is based on a modified and biased extended Kalman filter (BEKF) which is used in TDoA localization method. The results prove that this technique successfully detects the NLOS cases, mitigates the error up to a factor of 10 and leads to stability of the EKF method.

关键词： Localization TDoA NLOS UWB Extended Kalman Filter probability distribution function

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Proposition of Novel Evaluation Method and Values for Wireless Power Transfer With Modulated Waves

Proposition of Novel Evaluation Method and Values for Wirele...

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IEEE Wireless Power Technology Conference and Expo (WPTCE)

作者： Hirakawa, Takashi Hasegawa, Naoki Nakamoto, Yuta Takagi, Yuki Ohta, Yoshichika SoftBank Corp Technol Res Lab Tokyo Japan Tokyo Inst Technol Tokyo Japan

ISBN: (纸本)9798350349146;9798350349139

Flexible DC power supplying is necessary for the practical use of IoT. There are two main techniques for the power supply. One is the wireless power transfer (WPT) technique and the other is energy harvesting(EH). This paper focuses on WPT with modulated waves and radio-frequency(RF) energy harvesting. Both techniques use rectifiers for the conversion from modulated electromagnetic waves to direct current(DC) power. In recent research, it is revealed that the characteristics of rectifiers with modulated input are calculated with power probability distribution and rectifiers' own CW characteristics. Herein, we can make the general discussion of the modulated waves for WPT and EH. Previous research show that the modulated waves with high peak-to-average power ratio(PAPR) can improve the RF-DC conversion efficiency of rectifiers when the average input power is low. More strictly speaking, this fact means that the modulation improves the efficiency when the average input power is lower than 1 / PAPR times of the optimum CW input for each rectifier. This is absolutely correct and consistent with much experimental results. However, this is only the sufficient condition and not useful for the practical design. Herein, We focused on the practical and novel evaluation method for the WPT and EH with general modulations. This paper proposes the novel evaluation method for modulations. Our method uses a weighted power probability distribution(PPD). The average and variance of the weighted PPD are practical evaluation parameters for the modulations. The former value approximately equals to the optimum design power for the rectifier with modulated waves and we defined the value as "representative power". The other value can evaluate the modulation quality for WPT. We also show the consistency of these values by comparing with the simulation results.

关键词： theory modulated wave probability distribution function peak-to-average power ratio i-v characteristics RF-DC conversion efficiency wireless power transmission

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Free-Space Optical Communication Channel Modeling 3rd

Free-Space Optical Communication Channel Modeling

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3rd International Conference on Advanced Computing, Networking, and Informatics (ICACNI)

作者： Rao, G. Eswara Jena, Hara Prasana Mishra, Aditya Shaswat Patnaik, Bijayananda VITAM Berhampur Orissa India IIIT Bhubaneswar Orissa India

ISBN: (纸本)9788132225386;9788132225379

Free-space optical (FSO) systems have proved as the best technologies for communication and surveillance systems. These systems are merged with other technologies for providing robust applications. In FSO systems, when laser light is transmitted through the atmospheric channel, severe absorption is observed especially because of fog, snow, heavy rain etc. Therefore, we have discussed here different free space optical channel modelling techniques for mitigating these effects.

关键词： Free-space optics Atmospheric turbulence Rayleigh distribution Gama-Gama modeling probability distribution function

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On the parametric approach to unit hydrograph identification

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Water Resources Management 1989年第2期3卷 107-128页

作者： Koutsoyiannis, Demetris Xanthopoulos, Themistocle Department of Civil Engineering Division of Water Resources National Technical University of Athens Zografou GR-15773 5 Iroon Polytechniou Greece

Unit hydrograph identification by the parametric approach is based on the assumption of a proper analytical form for its shape, using a limited number of parameters. This paper presents various suitable analytical forms for the instantaneous unit hydrograph, originated from known probability density functions or transformations of them. Analytical expressions for the moments of area of these form versus their definition parameters are theoretically derived. The relation between moments and specific shape characteristics are also examined. Two different methods of parameter estimation are studied, the first being the well-known method of moments, while the second is based on the minimization of the integral error between derived and recorded flood hydrographs. The above tasks are illustrated with application examples originated from case studies of catchments in Greece. © 1989 Kluwer Academic Publishers.

关键词： identification instantaneous unit hydrograph method of moments optimization probability density function probability distribution function Unit hydrograph

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Equivalent Bandwidth Estimation under Delay Constrains

Equivalent Bandwidth Estimation under Delay Constrains

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2000 International Conference on Communication Technology(WCC2000·ICCT2000)

作者： Liu Yanyu Zhang Zhifei Tu Pinghui ITS Research Center of Nothern Jiaotong University Information Institute of Northern Jiaotong University Civil Engineering Institute of Noth Jiaotong University

ISBN: (纸本)0780363949

Delay plays an important role in real-time multimedia *** this paper,the delay probability distribution function(pdf) and the approximate expression for the equivalent bandwidth for the real-time multimedia flow have been developed with fluid flow *** impacts of some relevant parameters have been investigated by numerical computation and simulation *** expression is computationally simple and convenient for real-time bandwidth estimation and control.

关键词： delay probability distribution function delay constrain equivalent bandwidth

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