Engineering Commons^™

Grid Connected Roof Top Solar Power Generation: A Review, Radhey Shyam Meena

Radhey Shyam Meena

India is blessed with rich solar energy and if exploited efficiently, the country has the potential of producing trillionkilowatts of electricity. Sunlight is converted to electricity directly when made to fall on solar photovoltaic (SPV) modules. Systems /devices are made for various applications based on SPV modules connected with suitably designed power conditioning units for meeting electricity requirements. These systems/devices are designed to work in offgrid mode (usually supported with batteries to allow use when sunlight is low or during night). In recent years solar PV systems became viable and attractive. Utility scale plants are being set up worldwide with …

Static Security Enhancement And Loss Minimization Using A Simulated Annealing Based Approach, Almoataz Youssef Abdelaziz

Almoataz Youssef Abdelaziz

A developed algorithm for optimal placement and sizing of thyristor controlled series capacitors (TCSC’s) for enhancing the static security of power system and minimizing the overall power system loss is presented in this paper. A procedure to determine the optimal locations and sizes of the thyristor controlled series capacitors is illustrated and presented. The locations are determined by evaluating contingency sensitivity index (CSI) for a given power system branch for a given number of contingencies. Optimal sizes of TCSC’s are determined by the optimization technique of simulated annealing (SA), where TCSC’s settings are chosen to minimize the overall power system …

Modeling Of Wide-Bandgap Power Semiconductor Devices—Part Ii, Kang Peng

Kang Peng

Energy Conservation Day: Symbolism Doesn’T Pay, Hippu Salk Kristle Nathan

Hippu Salk Kristle Nathan

The much publicised panting competition at school level on the occasion of Energy Conservation Day was a good effort to send message to consumers to influence their energy consumption behaviour. But the effect is minuscule.

As a child one might have walked or cycled to school. But as a breadwinner, once energy related decisions largely get influenced by one's income level and opportunities and restrictions.

A Portable Wireless Particulate Sensor System For Continuous Real-Time Environmental Monitoring, James A. Hall Jr., Sin Ming Loo, Dale Stephenson, Ross Butler, Michael Pook, Joshua Kiepert, Jordan Anderson, Nicholas Terrell

Dale J. Stephenson

Airborne particulate matter has been shown to be associated with morbidity and mortality, and may interfere with certain sensitive experiment. Understanding the levels and movements of particulate matter in an enclosed space can lead to a reduction in the impact of this material on health and experimental results. A system of environmental sensors including particulate matter, selected gasses, humidity, temperature, and pressure can be used to assist in tracking air movement, providing real-time mapping of potential contaminants as they move through a space. In this paper we present a system that is capable of sensing these environmental factors, collecting data …

H-Matrix-Based Fast Direct Finite Element Solver For Large-Scale Electromagnetic Analysis, Haixin Liu, Dan Jiao

Haixin Liu

In this work, we prove that the sparse matrix resulting from a finite-element-based analysis of electrodynamic problems can be represented by an H-matrix without any approximation, and the inverse of this sparse matrix has a data-sparse H-matrix approximation with error well controlled. Based on this proof, we develop an H-matrix-based direct finite-element solver of O(kNlogN) memory complexity and O(k2Nlog2N) time complexity for solving electromagnetic problems, where k is a small variable that is adaptively determined based on accuracy requirements, and N is the number of unknowns. Both inversebased and LU-based direct solutions are developed. The LU-based solution is further accelerated …

Lna Integrates Fast Shutdown Function, Chin-Leong Lim

Chin-Leong Lim

To minimize dead time in time domain duplex (TDD) transceiver, reception should ideally commence as soon as transmission ends. However, the low noise amplifier (LNA), which is typically shutdown during transmission to prevent device damage and receiver overload, can exhibit a turn-on delay. In older implementations, the shutdown function is external to the LNA device. So, one way to reduce part count and to miniaturize this class of LNA is to integrate the LNA and shutdown function in a microwave monolithic integrated circuit (MMIC). The integration also allows the shutdown circuit to be connected to the LNA at an optimum …

Power Variation With Electret Surface Potential And Frequency Of Vibration In Vertical Vibration Based Cantilever-Electret Micro-Power Generation, Innovative Research Publications Irp India, Akin-Ponnle A.E, Ponnle A.A, Falaki S.O.

Innovative Research Publications IRP India

A cantilever-electret based electrostatic micro-power generator for energy harvesting was set up in which Cyclic Transparent Optical Polymer (CYTOP) was used as the electret, and the upper electrode was made in form of an Ashaped cantilever which was fabricated from materials of copper with embedded glass epoxy. The cantilever was vibrated in the vertical direction in close to contact point mode of operation. Experimental result showed that the average output power increases with increasing electret surface potential, and the minimum distance to contact point decreases with increasing electret surface potential. Also, variation of output power with frequency was investigated by …

Desert Rhex Technical Report: Jornada And White Sands Trip, Sonia Roberts, Jeff Duperret, Aaron M. Johnson, Scott Van Pelt, Ted Zobeck, Nick Lancaster, Daniel E. Koditschek

Sonia F. Roberts

Researchers in a variety of fields, including aeolian science, biology, and environmental science, have already made use of stationary and mobile remote sensing equipment to increase their variety of data collection opportunities. However, due to mobility challenges, remote sensing opportunities relevant to desert environments and in particular dune fields have been limited to stationary equipment. We describe here an investigative trip to two well-studied experimental deserts in New Mexico with D-RHex, a mobile remote sensing platform oriented towards desert research. D-RHex is the latest iteration of the RHex family of robots, which are six-legged, biologically inspired, small (10kg) platforms with …

Review Of Normal And Infrequent In-Feed Loss Risks In The Transmission System Of Oman, Omar H. Abdalla, Adil Al-Busaidi, Hilal Al-Hadi, Hisham A. Al-Riyami, Ahmed Al-Nadabi

Omar H. Abdalla

The paper presents technical studies performed to review the values of the Normal Infeed Loss Risk (NILR) and Infrequent Infeed Loss Risk (IILR) in the Transmission System Security Standard (TSSS). The objective is to facilitate the connection of the largest power station in Oman, which is Sur 2000 MW IPP, to the Main Interconnected Transmission System (MITS), while complying with the requirements of the TSSS. The full output of 2000 MW of Sur power plant is expected to available in 2015; therefore the MITS model of 2015 is used in the studies using the DIgSILENT professional software. The model includes …

Implementation Of Multi Mode Aes Algorithm Using Verilog, Innovative Research Publications Irp India, P Penchala Reddy, Dr.V. Thrimurthulu, K. Jagadeesh Kumar

Innovative Research Publications IRP India

Increasing need of high security in communication led to the development of several cryptographic algorithms hence sending data securely over a transmission link is critically important in many applications. NIST in the beginning selected Rijndael within October 2000 and formal adoption as being the AES standard started in December 2001. FIPS PUB 197 explains a 128-bit block cipher making Ause of a 128, 192, or 256-bit key. In cryptography, modes of operation enable the repeated and secure use of a block cipher under a single key. This paper presents implementation of multi mode AES algorithm with three modes ECB, CBC …

On Modeling Eavesdropping Attacks In Wireless Networks, Xuran Li, Jianlong Xu, Hong-Ning Dai, Qinglin Zhao, Chak Fong Cheang, Qiu Wang

Hong-Ning Dai

This paper concerns the eavesdropping attacks from the eavesdroppers’ perspective, which is new since most of current studies consider the problem from the good nodes’ perspective. In this paper, we originally propose an analytical framework to quantify the effective area and the probability of the eavesdropping attacks. This framework enables us to theoretically evaluate the impact of node density, antenna model, and wireless channel model on the eavesdropping attacks. We verify via extensive simulations that the proposed analytical framework is very accurate. Our results show that the probability of eavesdropping attacks significantly vary, depending on the wireless environments (such as …

Estimating Effective Connectivity From Fmri Data Using Factor-Based Subspace Autoregressive Models, Chee-Ming Ting Phd, Abd-Krim Seghouane Phd, Sh-Hussain Salleh Phd, Alias M. Noor Phd

Chee-Ming Ting

Modeling And Estimation Of Single-Trial Event-Related Potentials Using Partially Observed Diffusion Processes, Chee-Ming Ting Phd, Sh-Hussain Salleh, Z. M. Zainuddin, Arifah Bahar

Chee-Ming Ting

This paper proposes a new modeling framework for estimating single-trial event-related potentials (ERPs). Existing studies based on state-space approach use discrete-time random-walk models. We propose to use continuous-time partially observed diffusion process which is more natural and appropriate to describe the continuous dynamics underlying ERPs, discretely observed in noise as single-trials. Moreover, the flexibility of the continuous-time model being specified and analyzed independently of observation intervals, enables a more efficient handling of irregularly or variably sampled ERPs than its discrete-time counterpart which is fixed to a particular interval. We consider the Ornstein–Uhlenbeck (OU) process for the inter-trial parameter dynamics and …

Influence Of Oxygen On Electronic Properties Of Nanocrystalline Silicon, Shantan Kajjam

Shantan Kajjam

Nanocrystalline Silicon (nc-Si) is an important material for photovoltaic device applications. Its excellent absorption, low defect levels and many other interesting properties help build high efficiency solar cells. Its structure is very complex and is sensitive to contaminants and fabrication processes. It needs a careful study so that a maximum outcome can be attained from the material. Nc-Si is highly prone to be defective and oxygen is one of the major sources of the defects. In this thesis, systematic analysis of the fundamental properties of oxygen doped & boron compensated nc-Si are illustrated. Thin film solar cells were fabricated using …

Emerging Role Of Photovoltaics For Sustainably Powering Underdeveloped, Emerging, And Developed Economies, Rajendra Singh, Amir A. Asif, Ganesh K. Venayagamoorthy, Akhlesh Lakhtakia, Mahmoud Abdelhamid, Githin F. Alapatt, David A. Ladner

Mahmoud M Abdelhamid

With the advent of low-cost solar photovoltaic (PV) panels and our ability to generate, store, and use electrical energy locally without the need for long-range transmission, the world is about to witness transformational changes in electricity infrastructures. The use of DC electricity enhances systemwide efficiency. DC microgrids and nanogrids powered by solar PV systems and gigawatt batteries for electricity storage can sustainably power the needs of all human beings equitably and empower every individual. Ultralarge-scale manufacturing of PV systems and batteries, a vertically integrated business model, and a targeted monetary policy of quantitative easing can rapidly power all human activities.

Sptf: Smart Photo-Tagging Framework On Smart Phones, Hao Xu, Hong-Ning Dai, Walter Hon-Wai Lau

Hong-Ning Dai

Smart phones, as one of the most important platforms for personal communications and mobile computing, have evolved with various embedded devices, such as cameras, Wi-Fi transceivers, Bluetooth transceivers and sensors. Specifically, the photos taken by a smart phone has the approximate or even equivalent image quality to that of a professional camera. As a result, smart phones have become the first choice for people to take photos to record their ordinary life. However, how to manage thousands of photos on a smart phone becomes a challenge. In this paper, we propose a new architecture in terms of Smart Photo-Tagging Framework …

Development Of Impedance Spectroscopy Based In-Situ, Self-Calibrating, On-Board Wireless Sensor With Inbuilt Metamaterial Inspired Small Antenna For Constituent Detection In Multi-Phase Mixtures Like Soil, Gunjan Pandey

Gunjan Pandey

Real time and accurate measurement of sub-surface soil moisture and nutrients is critical for agricultural and environmental studies. This work presents a novel on-board solution for a robust, accurate and self-calibrating soil moisture and nutrient sensor with inbuilt wireless transmission and reception capability that makes it ideally suited to act as a node in a network spread over a large area. The sensor works on the principle of soil impedance measurement by comparing the amplitude and phase of signals incident on and reflected from the soil in proximity of the sensor. The permittivity of the soil dielectric mixture which is …

Evaluation Of On-Board Photovoltaic Modules Options For Electric Vehicles, Mahmoud M. Abdelhamid

Mahmoud M Abdelhamid

This paper presents an overview of different commercial photovoltaic (PV) module options to power on-board electric vehicles (EVs). We propose the evaluation factors, constraints, and the decision-making criteria necessary to assess the suitability of this PV module for this application. The incorporation of quality function deployment (QFD) and the analytical hierarchy process (AHP) is the decision-making methodology used in this study. Our approach is innovative and robust in that the evaluation depends upon data collected from PV manufactures datasheets. Unlike traditional research, a hybrid AHP and QFD innovative decision-making methodology has been created, and current commercial PV market data for …

Inferring The Global Cosmic Dust Influx To The Earth’S Atmosphere From Lidar Observations Of The Vertical Flux Of Mesospheric Na, Chester S. Gardner, Alan Z. Liu, Dan Marsh, Wuhu Feng, John Plane

Alan Z Liu

The Gasday Project At Marquette University: A Learning Laboratory In A Functioning Business, Ronald H. Brown, Thomas F. Quinn, George Corliss, Jay R. Goldberg, Mark L. Nagurka

George F Corliss

No abstract provided.

Design And Implementation Of A Byzantine Fault Tolerance Framework For Non-Deterministic Applications, H. Zhang, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith

Wenbing Zhao

State-machine-based replication is an effective way to increase the availability and dependability of mission-critical applications. However, all practical applications contain some degree of non-determinism. Consequently, ensuring strong replica consistency in the presence of application non-determinism has been one of the biggest challenges in building dependable distributed systems. In this Study, the authors propose a classification of common types of application non-determinism with respect to the requirement of achieving Byzantine fault tolerance (BFT), and present the design and implementation of a BFT framework that controls these types of non-determinism in a systematic manner.

End-To-End Latency Of A Fault-Tolerant Corba Infrastructure, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith

Wenbing Zhao

This paper presents an evaluation of the end-to-end latency of a fault-tolerant CORBA infrastructure that we have implemented. The fault-tolerant infrastructure replicates the server applications using active, passive and semi-active replication, and maintains strong replica consistency of the server replicas. By analyses and by measurements of the running fault-tolerant infrastructure, we characterize the end-to-end latency under fault-free conditions. The main determining factor of the run-time performance of the fault-tolerant infrastructure is the Totem group communication protocol, which contributes to the end-to-end latency primarily in two ways: the delay in sending messages and the processing cost of the rotating token. To …

Low Loss Configuration For Integrated Pin-Schottky Limiters, Chin-Leong Lim

Chin-Leong Lim

Compared to the PIN diode limiter, the Schottky-PIN limiter improves receiver protection, but has a higher insertion loss. Low cost, plastic packaged diodes can further worsen the loss. Diode stacking, mesa diode construction, and isolating the Schottky diode with a high-impedance quarter wave line or a directional coupler can reduce loss, but detrimentally raises the limiting threshold and/or adds bulk or cost. The PIN-Schottky limiter’s insertion loss can be improved by integrating the diodes’ parasitic capacitances into a low pass ladder network, but this solution requires the PIN diode to have two anode connections. Recently, the PIN-Schottky limiter was integrated …

Feedback Control For Multi-Modal Optimization Using Genetic Algorithms, Jun Shi, Ole J. Mengshoel, Dipan K. Pal

Ole J Mengshoel

Estimation Of High-Dimensional Brain Connectivity From Fmri Data Using Factor Modeling, Chee-Ming Ting Phd, Abd-Krim Seghouane, Sh-Hussain Salleh, Alias M. Noor

Chee-Ming Ting

We consider identifying effective connectivity of brain networks from fMRI time series. The standard vector autoregressive (VAR) models fail to give reliable network estimates, typically involving very large number of nodes. This paper adopts a dimensionality reduction approach based on factor modeling, to enable effective and efficient high-dimensional VAR analysis of large network connectivity. We derive a subspace VAR (SVAR) model from the factor model (FM) in which the observations are driven by a lower dimensional subspace of common latent factors, following an autoregressive dynamics. We consider the principal components (PC) method which can produce consistent estimators for the FM, …

Estimating Dynamic Cortical Connectivity From Motor Imagery Eeg Using Kalman Smoother & Em Algorithm, S. Balqis Samdin, Chee-Ming Ting Phd, Sh-Hussain Salleh, Mahyar Hamedi, Alias Mohd Noor

Chee-Ming Ting

This paper considers identifying effective cortical connectivity from scalp EEG. Recent studies use time-varying multivariate autoregressive (TV-MAR) models to better describe the changing connectivity between cortical regions where the TV coefficients are estimated by Kalman filter (KF) within a state-space framework. We extend this approach by incorporating Kalman smoothing (KS) to improve the KF estimates, and the expectation-maximization (EM) algorithm to infer the unknown model parameters from EEG. We also consider solving the volume conduction problem by modeling the induced instantaneous correlations using a full noise covariate. Simulation results show the superiority of KS in tracking the coefficient changes. We …

From Verification To Implementation: A Model Translation Tool And A Pacemaker Case Study, Miroslav Pajic, Zhihao Jiang, Insup Lee, Oleg Sokolsky, Rahul Mangharam

Oleg Sokolsky

Model-Driven Design (MDD) of cyber-physical systems advocates for design procedures that start with formal modeling of the real-time system, followed by the model’s verification at an early stage. The verified model must then be translated to a more detailed model for simulation-based testing and finally translated into executable code in a physical implementation. As later stages build on the same core model, it is essential that models used earlier in the pipeline are valid approximations of the more detailed models developed downstream. The focus of this effort is on the design and development of a model translation tool, UPP2SF, and …

Model-Driven Safety Analysis Of Closed-Loop Medical Systems, Miroslav Pajic, Rahul Mangharam, Oleg Sokolsky, David Arney, Julian M. Goldman, Insup Lee

Oleg Sokolsky

In modern hospitals, patients are treated using a wide array of medical devices that are increasingly interacting with each other over the network, thus offering a perfect example of a cyber-physical system. We study the safety of a medical device system for the physiologic closed-loop control of drug infusion. The main contribution of the paper is the verification approach for the safety properties of closed-loop medical device systems. We demonstrate, using a case study, that the approach can be applied to a system of clinical importance. Our method combines simulation-based analysis of a detailed model of the system that contains …

Multi-Channel Wireless Networks With Infrastructure Support: Capacity And Delay, Hong-Ning Dai, Raymond Chi-Wing Wong, Qinglin Zhao

Hong-Ning Dai

No abstract provided.