Lehmer's generalized Euler numbers in hypergeometric functions

Rupam Barman,Takao Komatsu 대한수학회 2019 대한수학회지 Vol.56 No.2

In 1935, D. H. Lehmer introduced and investigated generalized Euler numbers $W_n$, defined by $$ \frac{3}{e^{t}+e^{\omega t}+e^{\omega^2 t}}=\sum_{n=0}^\infty W_n\frac{t^n}{n!}\,, $$ where $\omega$ is a complex root of $x^2+x+1=0$. In 1875, Glaisher gave several interesting determinant expressions of numbers, including Bernoulli and Euler numbers. These concepts can be generalized to the hypergeometric Bernoulli and Euler numbers by several authors, including Ohno and the second author. In this paper, we study more general numbers in terms of determinants, which involve Bernoulli, Euler and Lehmer's generalized Euler numbers. The motivations and backgrounds of the definition are in an operator related to Graph theory. We also give several expressions and identities by Trudi's and inversion formulae.

Demand Aware Voltage Control of Hybrid Renewable Energy Tied Uneven Multi-level Smart Inverter

Rupam Bhaduri,Soubhik Bagchi,G. Renukaprasad 한국전기전자재료학회 2019 Transactions on Electrical and Electronic Material Vol.20 No.3

This paper proposes a smart multi-level inverter with hybrid energy sources to increase the power quality, improve the number of voltage levels and reduce the total harmonic distortion. A single power source used in the distribution system is not convenient for all weather conditions. Our proposed work uses hybrid power source, which is the combination of solar and wind energy. The proposed smart multi-level inverter on this paper works for high power and medium voltage situations. The smart sensing unit decides the level of multi-level inverter to supply the power based on the demand, which avoids the energy loss across transmission line. An iterative Maximum Power Point Tracker is used to maximize the power extraction under all conditions. The design and implementation of the multi-level inverter with N-level cascaded H-bridge inverter using two DC power sources does not cause any complexity to the power circuit. The sinusoidal pulse width modulation is used to minimize the harmonic distortion caused by a high-level overlapping at a defi nite interval. The presented system is executed using Matlab/Simulink and is highly acceptable for industrial and commercial applications.

Supervisory Controller for Power Management of Microgrid Using Hybrid Technique

Rupam Bhaduri,G. Rahul Saravana,C. Vaskar 한국전기전자재료학회 2020 Transactions on Electrical and Electronic Material Vol.21 No.1

Power management in Microgrid (MG) is a major issue while utilizing generation elements like photovoltaic, wind turbine, distributed generator, and battery bank with loads and non-linear loads. In this paper, power management is achieved through the deployment of the supervisory controller with hybrid power management algorithm named Artifi cial Neuro-Fuzzy Interference System (ANFIS) with Elephant Herd Optimization (EHO) algorithm. The objective of the new control technique is to keep a stable power fl ow among all renewable energy sources and the load, thereby ensuring that the battery power doesnot exceed the design limits. For an optimal control mapping of the nonlinear relation, ANFIS considers two input error values such as voltage and current value to obtain a minimized error value. The EHO is used to attain the learning function of the ANFIS. Here, the generated power, load demand power and State of Charge are taken as an objective function in EHO to compensate the load with the battery service during unavailability of generated power for meeting the load demand. The supervisory control structure achieves better power management in the MG with the help of the ANFIS–EHO. The proposed method is implemented in Simulink/MATLAB platform. The simulation and the experimental results are investigated with four test cases with some existing methods to analyze the effi ciency of the proposed method.

Augmented World: Real Time Gesture Based Image Processing Tool with Intel RealSense™ Technology

Rupam Das,Dr. K. B. Shivakumar 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.1

Intel RealSense™ is an exciting new technology that offers innovative multimodal human computer interaction with hand tracking, face tracking, emotion detection, speech synthesis and voice recognition. The technology supports real time background separation by combining the depth and RGB streams of RealSense™ camera. Several past works have provided robust techniques for background separation. Background separated frame is used to augment segmented user photo in an artificial scene. In this work we propose a novel real time technique for augmenting the user in an artificial scene and apply various image filters on the constructed scene. We also propose a “Split Grid” based novel hand gesture driven UI control system that enables the user an intuitive way of working with the system with on-air hand movement and gesture. The system can be used in a wide range of applications like puppetry, photo retouching, and video recording on augmented scene .Usability tests performed by both amateur as well as professional digital photo artists proves ease and efficiency of the tool in generating quick wonderful photo effect in multimodal environment.

Wireless Power Transfer System Evaluation in a Pacemaker

Rupam Das(루팜 다스),Hypungsuk Yoo(유형석) 대한전기학회 2013 대한전기학회 학술대회 논문집 Vol.2013 No.10

Demand Aware Voltage Control of Hybrid Renewable Energy Tied Uneven Multi-level Smart Inverter

Rupam Bhaduri,Soubhik Bagchi,G. Renukaprasad 한국전기전자재료학회 2019 Transactions on Electrical and Electronic Material Vol.20 No.2

This paper proposes a smart multi-level inverter with hybrid energy sources to increase the power quality, improve the number of voltage levels and reduce the total harmonic distortion. A single power source used in the distribution system is not convenient for all weather conditions. Our proposed work uses hybrid power source, which is the combination of solar and wind energy. The proposed smart multi-level inverter on this paper works for high power and medium voltage situations. The smart sensing unit decides the level of multi-level inverter to supply the power based on the demand, which avoids the energy loss across transmission line. An iterative Maximum Power Point Tracker is used to maximize the power extraction under all conditions. The design and implementation of the multi-level inverter with N-level cascaded H-bridge inverter using two DC power sources does not cause any complexity to the power circuit. The sinusoidal pulse width modulation is used to minimize the harmonic distortion caused by a high-level overlapping at a defi nite interval. The presented system is executed using Matlab/Simulink and is highly acceptable for industrial and commercial applications.

Biotelemetry and Wireless Powering for Leadless Pacemaker Systems

Das, Rupam,Hyoungsuk Yoo THE INSTITUTE OF ELECTRICAL ENGINEERS 2015 IEEE Microwave and Wireless Components Letters Vol. No.

<P>In this letter, we address the telemetry and wireless powering problems associated with the recently invented leadless pacemaker. To overcome the telemetry problem, we propose a conformal spiral type Implantable antenna at Medical Implanted Communication Service (MICS) band. In addition, we also apply the recently proposed midfield wireless power transfer (WPT) technique at 1.5 GHz to avoid the bulky energy storage component. We simulate and experimentally measure the performance of the implantable antenna by using porcine heart tissue. Our research shows that, the implantable antenna and wireless power transfer scheme can be implemented in a leadless pacemaker without any significant coupling between them.</P>

A Wideband Circularly Polarized Conformal Endoscopic Antenna System for High-Speed Data Transfer

Das, Rupam,Yoo, Hyoungsuk Institute of Electrical and Electronics Engineers 2017 IEEE transactions on antennas and propagation Vol.65 No.6

<P>In this paper, a conformal wideband circularly polarized (CP) antenna is presented for endoscopic capsule application over the 915-MHz Industrial, Scientific, and Medical (902-928 MHz) band. The thickness of the antenna is only 0.2 mm, which can be wrapped inside a capsule's inner wall. By cutting meandered slots on the patch, using open-end slots on the ground, and utilizing two long arms, the proposed antenna obtains a significant size reduction. In the conformal form, the antenna volume measures only 66.7 mm(3). A single-layer homogeneous muscle phantom box is used for the initial design and optimization with parametric studies. The effect of the internal components inside a capsule is discussed in analyzing the antenna's performance and to realize a more practical scenario. In addition, a realistic human body model in a Remcom XFdtd simulation environment is considered to evaluate the antenna characteristics and CP purity, and to specify the specific absorption rate limit in different organs along the gastrointestinal tract. The performance of the proposed antenna is experimentally validated by using a minced pork muscle phantom and by using an American Society for Testing and Materials phantom immersed in a liquid solution. For measurements, a new technique applying a printed 3-D capsule is devised. From simulations and measurements, we found that the impedance bandwidth of the proposed antenna is more than 20% and with a maximum simulated axial ratio bandwidth of around 29.2% in homogeneous tissue. Finally, a wireless communication link at a data rate of 78 Mb/s is calculated by employing link-budget analysis.</P>

Cogging Torque Minimization of PMBLDC Motor for Application in Battery Electric Vehicle

Bansal Rupam,Marwaha Sanjay,Verma Chaman 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

Since the beginning, researchers have focused globally on the automotive industry, which recently yielded a notable increase in the development of electric vehicles. The cogging torque of the motor is the leading cause of acoustic noise and vibration. Therefore, this paper aims to reduce the cogging torque of Brushless DC motors in electric vehicles. The power rating of the two-wheeler battery electric vehicle is determined with kinematic dynamic equations. The choice of material and the combination of pole slots impact the vehicle’s overall performance, particularly in raising the average torque of the motor. Finite element based Ansys Maxwell electromagnetic field simulation software has been used to design and analyze the electric and magnetic field parameters of BLDC motor using several rotor poles embrace factor values. The findings of this study are expected to reduce vibration and noise in electric vehicles with increased average torque.

LEHMER'S GENERALIZED EULER NUMBERS IN HYPERGEOMETRIC FUNCTIONS

Barman, Rupam,Komatsu, Takao Korean Mathematical Society 2019 대한수학회지 Vol.56 No.2

In 1935, D. H. Lehmer introduced and investigated generalized Euler numbers $W_n$, defined by $${\frac{3}{e^t+e^{wt}e^{w^2t}}}={\sum\limits_{n=0}^{\infty}}W_n{\frac{t^n}{n!}}$$, where ${\omega}$ is a complex root of $x^2+x+1=0$. In 1875, Glaisher gave several interesting determinant expressions of numbers, including Bernoulli and Euler numbers. These concepts can be generalized to the hypergeometric Bernoulli and Euler numbers by several authors, including Ohno and the second author. In this paper, we study more general numbers in terms of determinants, which involve Bernoulli, Euler and Lehmer's generalized Euler numbers. The motivations and backgrounds of the definition are in an operator related to Graph theory. We also give several expressions and identities by Trudi's and inversion formulae.