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Full-Text Articles in Engineering

Sci-Tech Book News Reviews, Susan Fingerman Apr 2013

Sci-Tech Book News Reviews, Susan Fingerman

Sci-Tech News

No abstract provided.


Maintaining The Master International Frequency Register, Frans G. Von Der Dunk Jan 2013

Maintaining The Master International Frequency Register, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

The present paper is the written elaboration of a presentation held under the same title at the workshop “International Regulations of Space Communications” held in Luxembourg on 24 and 25 May 2012. Consequently, the topic of this paper, the maintenance of the Master International Frequency Register as a key tool for allowing satellite communications to be a viable international sector of space activities, is viewed through the looking glass of the session title, “WRC-12 from the Perspective of International Telecommunications Law.”

In other words, it does not purport to deal with the actual details of maintaining the Register …


Vibration Energy Harvesting For Wireless Underground Sensor Networks, Salman Kahrobaee, Mehmet C. Vuran Jan 2013

Vibration Energy Harvesting For Wireless Underground Sensor Networks, Salman Kahrobaee, Mehmet C. Vuran

Department of Electrical and Computer Engineering: Faculty Publications

Recent developments in wireless underground communication have enabled the realization of underground sensor network applications. To this end, it is desirable to provide a sustainable operation for wireless underground sensor networks (WUSNs) with extended lifetimes as maintenance is significantly costly. One promising method towards sustainable operation is to harvest energy underground based on the vibration sources in the environment. However, to the best of our knowledge, underground vibration energy harvesting has not been investigated before. In this paper, the feasibility of vibration energy harvesting for WUSNs is investigated. First, an analytical framework is developed to model the maximum harvestable power …


Opto-Vlsi-Based Adaptive Optical Power Splitter/Combiner For Next Generation Dynamic Optical Telecommunication Networks, Haithem A. Mustafa Jan 2013

Opto-Vlsi-Based Adaptive Optical Power Splitter/Combiner For Next Generation Dynamic Optical Telecommunication Networks, Haithem A. Mustafa

Theses: Doctorates and Masters

The demand for optical power splitters is growing globally, due to the rapid deployment of fibre-to-the-premises, optical metropolitan area network (MAN), and active optical cables for TV/Video signal transport. Optical splitters play an important role in passive optical network (PON) technology by enabling several hundred users to share one optical line terminal. However, current PONs, which use fixed optical power splitters, have limited reconfigurability particularly in adding/dropping users to/from an optical network unit.

An adaptive optical power splitter (OPS) can dynamically reallocate the opticalpower in the entire network according to the real-time distribution of users and services, thus providing numerous …


A New Digital Image Steganography Algorithm Based On Visible Wavelength, İbrahi̇m Coşkun, Feyzi̇ Akar, Özdemi̇r Çeti̇n Jan 2013

A New Digital Image Steganography Algorithm Based On Visible Wavelength, İbrahi̇m Coşkun, Feyzi̇ Akar, Özdemi̇r Çeti̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Stenography is the science that ensures secret communication through multimedia carriers such as image, audio, and video files. The ultimate end of stenography is to hide the secret data in the carrier file so that they are not detected. To that end, stenography applications should have such features as undetectability; robustness; resistance to various images process, sing methods, and compression; and capacity of the hidden data. At the same time, those features distinguish stenography applications from watermarking and cryptography applications. This study is different from other studies in the literature in that the undetectability parameter has been achieved through hiding …


System-Generated Digital Forensic Evidence In Graphic Design Applications, Enos Mabuto, Hein Venter Jan 2013

System-Generated Digital Forensic Evidence In Graphic Design Applications, Enos Mabuto, Hein Venter

Journal of Digital Forensics, Security and Law

Graphic design applications are often used for the editing and design of digital art. The same applications can be used for creating counterfeit documents such as identity documents (IDs), driver’s licences, passports, etc. However, the use of any graphic design application leaves behind traces of digital information that can be used during a digital forensic investigation. Current digital forensic tools examine a system to find digital evidence, but they do not examine a system specifically for the creating of counterfeit documents created through the use of graphic design applications. The paper in hand reviews the system-generated digital forensic evidence gathered …


Contingency Analysis Of Power Systems In Presence Of Geomagnetically Induced Currents, Sivarama Karthik Vijapurapu Jan 2013

Contingency Analysis Of Power Systems In Presence Of Geomagnetically Induced Currents, Sivarama Karthik Vijapurapu

Theses and Dissertations--Electrical and Computer Engineering

Geomagnetically induced currents (GIC) are manifestations of space weather phenomena on the electric power grid. Although not a new phenomenon, they assume great importance in wake of the present, ever expanding power grids. This thesis discusses the cause of GICs, methodology of modeling them into the power system and the ramifications of their presence in the bulk power system. GIC is treated at a micro level considering its effects on the power system assets like Transformers and also at a macro level with respect to issues like Voltage instability. In illustration, several simulations are made on a transformer & the …


Complexity Reduction Of Rbf Multiuser Detector For Ds-Cdma Using A Genetic Algorithm, Mustafa Uğur Torun, Damla Gürkan Kuntalp Jan 2013

Complexity Reduction Of Rbf Multiuser Detector For Ds-Cdma Using A Genetic Algorithm, Mustafa Uğur Torun, Damla Gürkan Kuntalp

Turkish Journal of Electrical Engineering and Computer Sciences

The optimal receiver for detecting direct sequence code division multiple access (DS-CDMA) signals suffers from computational complexity that increases exponentially with the number of users. Several suboptimal multiuser detectors (MUDs) have been proposed to overcome this problem. Due to the nonlinear nature of the decision boundary of the optimal receiver, it is known that nonlinear receivers outperform linear receivers. Radial basis function (RBF) MUD is a nonlinear suboptimal receiver that can perfectly approximate this decision boundary and it needs no training since it is fully determined when the spreading codes of all users and the channel impulse response (CIR) are …


The Advanced Data Acquisition Model (Adam): A Process Model For Digital Forensic Practice, Richard Adams, Val Hobbs, Graham Mann Jan 2013

The Advanced Data Acquisition Model (Adam): A Process Model For Digital Forensic Practice, Richard Adams, Val Hobbs, Graham Mann

Journal of Digital Forensics, Security and Law

As with other types of evidence, the courts make no presumption that digital evidence is reliable without some evidence of empirical testing in relation to the theories and techniques associated with its production. The issue of reliability means that courts pay close attention to the manner in which electronic evidence has been obtained and in particular the process in which the data is captured and stored. Previous process models have tended to focus on one particular area of digital forensic practice, such as law enforcement, and have not incorporated a formal description. We contend that this approach has prevented the …


Smart Wall Plug Design For The Dc House Project, Edward Constant Sibal Dec 2012

Smart Wall Plug Design For The Dc House Project, Edward Constant Sibal

Master's Theses

The DC House project at Cal Poly State University faces a challenge of supplying DC voltage to household appliances. Each appliance in the DC House constitutes a DC load that has a unique voltage and power rating, hence the need to develop a smart DC wall plug that will automatically adjust to the operating voltage required by any DC load. This thesis entails a proof of concept design of the smart DC wall plug which can automatically detect an appliance’s voltage rating. The design employs a dc-dc converter in conjunction with a microcontroller to sense load current to properly adjust …


Wide Area Monitoring Of Rotor Angle Based On Synchrophasor Measurements, P. K. Olulope, Ganesh K. Venayagamoorthy, K. A. Folly Dec 2012

Wide Area Monitoring Of Rotor Angle Based On Synchrophasor Measurements, P. K. Olulope, Ganesh K. Venayagamoorthy, K. A. Folly

Electrical and Computer Engineering Faculty Research & Creative Works

The concept of phasor is designed for steady state and phasor measurement unit (PMU) is based on this concept. Measuring rotor angle therefore during transient has become a challenging task. This paper investigates the possibility of using data from PMU to estimate the internal variables of synchronous generator such as rotor angle of large power system during transient disturbance. the rotor angle is estimated from synchro phasor such as phasor voltage and current as well as their angles. the proposed method is implemented on IEEE 68 bus system. © 2012 IEEE.


Linear Precoding Of Finite Alphabet Signals In Multi-Antenna Broadcast Channels, Yongpeng Wu, Mingxi Wang, Chengshan Xiao, Zhi Ding, Xiqi Gao Dec 2012

Linear Precoding Of Finite Alphabet Signals In Multi-Antenna Broadcast Channels, Yongpeng Wu, Mingxi Wang, Chengshan Xiao, Zhi Ding, Xiqi Gao

Electrical and Computer Engineering Faculty Research & Creative Works

We investigate the design of linear transmit precoding for multiple-input multiple-output (MIMO) broadcast channels (BC) with finite alphabet input signals. We derive an explicit expression for the achievable rate region of the MIMO BC with discrete constellation inputs, which is generally applicable to cases involving arbitrary user number and arbitrary antenna configurations. for the case where all the users employ the same modulation scheme, we further present a weighted sum rate upper-bound of the MIMO BC with identical transmit precoding matrices. the resulting bound demonstrates a serious performance loss due to multi-user interference for MIMO BC with finite alphabet inputs …


Knowledge Dictionary For Information Extraction On The Arabic Text Data, Wahyu Syaifullah Jauharis Saputra, Agus Zainal Arifin, Anny Yuniarti Nov 2012

Knowledge Dictionary For Information Extraction On The Arabic Text Data, Wahyu Syaifullah Jauharis Saputra, Agus Zainal Arifin, Anny Yuniarti

Makara Journal of Technology

Information extraction is an early stage of a process of textual data analysis. Information extraction is required to get information from textual data that can be used for process analysis, such as classification and categorization. A textual data is strongly influenced by the language. Arabic is gaining a significant attention in many studies because Arabic language is very different from others, and in contrast to other languages, tools and research on the Arabic language is still lacking. The information extracted using the knowledge dictionary is a concept of expression. A knowledge dictionary is usually constructed manually by an expert and …


Agenda: 2012 Energy Justice Conference And Technology Exposition, University Of Colorado Boulder. Center For Energy & Environmental Security, University Of Colorado Boulder. Colorado European Union Center Of Excellence, University Of Colorado Boulder. Presidents Leadership Institute Sep 2012

Agenda: 2012 Energy Justice Conference And Technology Exposition, University Of Colorado Boulder. Center For Energy & Environmental Security, University Of Colorado Boulder. Colorado European Union Center Of Excellence, University Of Colorado Boulder. Presidents Leadership Institute

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Co-sponsored with the Colorado European Union Center of Excellence and the Presidents Leadership Institute at the University of Colorado Boulder.

The ability to harness energy is fundamental to economic and social development. Worldwide, almost 3 billion people have little or no access to beneficial energy resources for cooking, heating, water sanitation, illumination, transportation, or basic mechanical needs. Energy poverty exacerbates ill health and economic hardship, and reduces educational opportunities, particularly for women and children. Specifically, access to efficient and affordable energy services is a prerequisite for achieving the Millennium Development Goal (MDG) relating to poverty eradication.

In response, the UN …


Slides: Meeting The Needs Of Women Through Clean Cooking Solutions, Corinne Hart Sep 2012

Slides: Meeting The Needs Of Women Through Clean Cooking Solutions, Corinne Hart

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Presenter: Corinne Hart, Program Manager, Gender and Markets, Global Alliance for Clean Cookstoves

20 slides


Slides: Impacts Of Energy Deficits In Cooking, Illumination, Water, Sanitation, And Motive Power, Paul S. Chinowsky Sep 2012

Slides: Impacts Of Energy Deficits In Cooking, Illumination, Water, Sanitation, And Motive Power, Paul S. Chinowsky

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Presenter: Dr. Paul Chinowsky, Director, Mortenson Center in Engineering for Developing Communities; Professor, University of Colorado

25 slides


Slides: The Green Climate Fund: Challenges And Opportunities: Some Thoughts On How The Green Climate Fund Could Close The Energy Justice Gap, Martin Hiller Sep 2012

Slides: The Green Climate Fund: Challenges And Opportunities: Some Thoughts On How The Green Climate Fund Could Close The Energy Justice Gap, Martin Hiller

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Presenter: Martin Hiller, Director‐General, Renewable Energy and Energy Efficiency Partnership (REEEP), Vienna, Austria

22 slides


Slides: Session 3: Decision-Making And The Energy Poor, Andrew Yager Sep 2012

Slides: Session 3: Decision-Making And The Energy Poor, Andrew Yager

2012 Energy Justice Conference and Technology Exposition (September 17-18)

Presenter: Andrew Yager, United Nations Department of Economic and Social Affairs, Division for Sustainable Development

33 slides


An Energy Survey Of The Church Lane Building At Dit, Joseph Teehan Sep 2012

An Energy Survey Of The Church Lane Building At Dit, Joseph Teehan

Other resources

Within the European Union, the collective governments have introduced broad energy policies in order to increase energy efficiency and improve energy performance in new and existing buildings, within each member state. The following dissertation considers energy and how energy is used within the context of global and local consumption in an extensive literature review. Where does the future lie for Ireland and its energy sources? Policies, standards and regulations associated with energy efficiency and the Energy Performance of Buildings Directive (EPBD) are defined and briefly explained. The status of how well the response from the commercial building market to Building …


Ais-Based Coordinated And Adaptive Control Of Generator Excitation Systems For An Electric Ship, Chuan Yan, Ganesh Kumar Venayagamoorthy, Keith Corzine Aug 2012

Ais-Based Coordinated And Adaptive Control Of Generator Excitation Systems For An Electric Ship, Chuan Yan, Ganesh Kumar Venayagamoorthy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

An artificial immune system (AIS)-Based control of generator excitation systems for the U.S. Navy's electric ship is presented in this paper to solve power quality problems caused by high-energy loads such as direct energy weapons. the coordinated development of the AIS controllers mainly consists of two parts innate immunity (optimal) and adaptive immunity. the parameters of the controllers for the former, to provide optimal performance, are determined simultaneously using particle swarm optimization. for dramatic changes in the ship's power system, adaptive control based on the immune system feedback law is developed. the feedback law adapts the controllers' parameters only during …


Design And Polarimetric Calibration Of Dual-Polarized Phased Array Feeds For Radio Astronomy, Taylor D. Webb Jul 2012

Design And Polarimetric Calibration Of Dual-Polarized Phased Array Feeds For Radio Astronomy, Taylor D. Webb

Theses and Dissertations

Research institutions around the globe are developing phased array feed (PAF) systems for wide-field L-band radio astronomical observations. PAFs offer faster survey speeds and larger fields of view than standard single-pixel feeds, which enable rapid sky surveys and significantly increased scientific capability. Because deep space astronomical signals are inherently weak, PAF systems must meet stringent noise and sensitivity requirements. Meeting these requirements requires detailed modeling of the phased array itself as well as the reflector it is mounted on. This thesis details a novel approach to dual-pol PAF design that models the array and reflector as a complete system in …


Retrofitting A Car Alternator For Low-Speed Power Generation, Yuri Carrillo Jun 2012

Retrofitting A Car Alternator For Low-Speed Power Generation, Yuri Carrillo

Electrical Engineering

This report presents the analysis and methods taken to appropriately modify a car alternator to operate as a low speed generator for wind or hydro power generation. A Toyota car alternator taken from a junkyard is characterized via an Open-Circuit test to evaluate its operating specifications. The car alternator is also measured to determine its physical dimensions. The acquired values are used with the generated voltage equation to determine the machine’s unknown rotor values— the product of the rotor winding factor and the number of rotor windings (kfNf). Using the generated voltage equation with the determined machine parameters, the number …


Solar Powered Led Lantern For Developing Countries, Lacy Billingsly Iii Jun 2012

Solar Powered Led Lantern For Developing Countries, Lacy Billingsly Iii

Electrical Engineering

In recent years, both LED and solar technology have become the focus of sustainable energy. LED lighting uses significantly less power than its fluorescent competitor. Solar cells enable clean, natural, and portable power. As these two entities become more efficient at exponential rates, the hope for the wide use of off-grid lighting in less developed countries seemingly increases at the same rate. Currently, there has been a development of industry for portable solar powered lighting systems. Before designing a product, a study was conducted of current products on the market that aim to light dark homes. This study and design …


The Case For Open Source Appropriate Technology, Joshua M. Pearce Jun 2012

The Case For Open Source Appropriate Technology, Joshua M. Pearce

Michigan Tech Publications, Part 1

Much of the widespread poverty, environmental desecration, and waste of human life seen around the globe could be prevented by known (to humanity as a whole) technologies, many of which are simply not available to those that need it. This lack of access to critical information for sustainable development is directly responsible for a morally and ethically unacceptable level of human suffering and death. A solution to this general problem is the concept of open source appropriate technology or OSAT, which refers to technologies that provide for sustainable development while being designed in the same fashion as free and open …


Towards The Deployment And Adoption Of Location-Based Services For Optimal Mobile Communication Operations In Africa, Folasade Dahunsi May 2012

Towards The Deployment And Adoption Of Location-Based Services For Optimal Mobile Communication Operations In Africa, Folasade Dahunsi

The African Journal of Information Systems

Africa is the world’s second largest and second most populous continent with about one billion people. Mobile phones are a major source of communication and means of taking information and technology to rural and remote areas of the continent. With low-cost and readily available mobile phones, underprivileged, low-income earners and rural dwellers can also participate in the Information and Communication Technology (ICT) revolution. Services are introduced by mobile operators and vendors to enhance and optimize this mobile evolution. One of such service is location-based services (LBS); LBS make available personalized services based on the geographical location of the subscriber’s phone. …


Energy Harvesting-Aware Design Of Wireless Networks, Fabio Iannello May 2012

Energy Harvesting-Aware Design Of Wireless Networks, Fabio Iannello

Dissertations

Recent advances in low-power electronics and energy-harvesting (EH) technologies enable the design of self-sustained devices that collect part, or all, of the needed energy from the environment. Several systems can take advantage of EH, ranging from portable devices to wireless sensor networks (WSNs). While conventional design for battery-powered systems is mainly concerned with the battery lifetime, a key advantage of EH is that it enables potential perpetual operation of the devices, without requiring maintenance for battery substitutions. However, the inherent unpredictability regarding the amount of energy that can be collected from the environment might cause temporary energy shortages, which might …


The Xbox 360 And Steganography: How Criminals And Terrorists Could Be "Going Dark", Ashley Podhradsky, Rob D’Ovidio, Cindy Casey May 2012

The Xbox 360 And Steganography: How Criminals And Terrorists Could Be "Going Dark", Ashley Podhradsky, Rob D’Ovidio, Cindy Casey

Annual ADFSL Conference on Digital Forensics, Security and Law

Video game consoles have evolved from single-player embedded systems with rudimentary processing and graphics capabilities to multipurpose devices that provide users with parallel functionality to contemporary desktop and laptop computers. Besides offering video games with rich graphics and multiuser network play, today's gaming consoles give users the ability to communicate via email, video and text chat; transfer pictures, videos, and file;, and surf the World-Wide-Web. These communication capabilities have, unfortunately, been exploited by people to plan and commit a variety of criminal activities. In an attempt to cover the digital tracks of these unlawful undertakings, anti-forensic techniques, such as steganography, …


Mitigation Of Sea Ice Contamination In Quikscat Wind Retrieval, Weston Jay Hullinger Mar 2012

Mitigation Of Sea Ice Contamination In Quikscat Wind Retrieval, Weston Jay Hullinger

Theses and Dissertations

Satellite borne radar scatterometers provide frequent estimates of near surface wind vectors over the Earth's oceans. However in the polar oceans, the presence of sea ice in or near the measurement footprint can adversely a ect scatterometer measurements resulting in inaccurate wind estimates. Currently, such ice contamination is mitigated by discarding measurements within 50 km of detected sea ice. This approach is imperfect and causes loss of coverage. This thesis presents a new algorithm which detects ice-contaminated measurements based on a metric called the Ice Contribution Ratio (ICR) which measures the spatial ice contribution for each measurement. The ICR calculation …


Resource Scheduling Under Uncertainty In A Smart Grid With Renewables And Plug-In Vehicles, Ahmed Yousuf Saber, Ganesh K. Venayagamoorthy Mar 2012

Resource Scheduling Under Uncertainty In A Smart Grid With Renewables And Plug-In Vehicles, Ahmed Yousuf Saber, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power system and transportation sector are our planet's main sources of greenhouse gas emissions. Renewable energy sources (RESs), mainly wind and solar, can reduce emissions from the electric energy sector; however, they are very intermittent. Likewise, next generation plug-in vehicles, which include plug-in hybrid electric vehicles and electric vehicles with vehicletogrid capability, referred to as grid able vehicles (GVs) by the authors, can reduce emissions from the transportation sector. GVs can be used as loads, energy sources (small portable power plants) and energy storage units in a smart grid integrated with renewable energy sources. However, uncertainty surrounds the controllability …


Trust Management Schemes For Peer-To-Peer Networks, Lin Cai Jan 2012

Trust Management Schemes For Peer-To-Peer Networks, Lin Cai

Dissertations

Peer-to-peer (P2P) networking enables users with similar interests to exchange, or obtain files. This network model has been proven popular to exchange music, pictures, or software applications. These files are saved, and most likely executed, at the downloading host. At the expense of this mechanism, worms, viruses, and malware find an open front door to the downloading host and gives them a convenient environment for successful proliferation throughout the network. Although virus detection software is currently available, this countermeasure works in a reactive fashion, and in most times, in an isolated manner. A trust management scheme is considered to contain …