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(221 - 240 of 392)
Pages
- Title
- PRIORITY MECHANISM DESIGN FOR INCOMING TRAFFIC IN 4G LTE NETWORK
- Creator
- Desai, Niraj N.
- Date
- 2012-11-27, 2012-12
- Description
-
Long Term Evolution (LTE) is currently being used for commercial networks and the same technology will also be used for Public Safety (PS)...
Show moreLong Term Evolution (LTE) is currently being used for commercial networks and the same technology will also be used for Public Safety (PS) applications. As a way to maximize network usage and also to allow PS users to share the commercial networks especially during emergency or disaster situations, PS users need to co-exist with commercial users in a shared network environment. To ensure proper assignment of resources in a network originated call scenario, priority mechanisms have been proposed in this report. Priority mechanism in terms of assignment of resources for the user plane, for scheduling of resources in the control plane, and for meeting Quality of Service (QoS) requirements have been discussed. To provide priority treatment, the use of a new parameter named Call Priority Number (CPN) generated by the Policy control and Charging Rules Function (PCRF) is proposed. This parameter signifies the priority of a call in terms of the caller priority, the callee priority and the priority of the application. For incoming calls, the functionality of providing priority mechanism for resource assignment using CPN is proposed to be in the Mobility Management Entity (MME). The functionality for scheduling resources in the control plane, for performing paging, for priority mechanism functionality that uses CPN and the implementation of using different paging cycles for the users based on their priority resides in the evolved NodeB (eNodeB). For managing the priority based on QoS, a mapping of the priority of applications served by LTE networks to the Differentiated Services has been proposed. The mapping can be implemented in the Packet data network Gate Way (PGW). The proposals are verified by simulation. The results show that the PS users are assigned the x required resources for the user plane, they get prioritized QoS treatment within the LTE network, and the PS users are given higher priority over the commercial users. As a result of the techniques proposed in this report, the time it takes to set up a call between PS users is reduced, the number of dropped calls for the PS user decrease, and the PS users have a faster access to network resources.
M.S. in Electrical Engineering, December 2012
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- Title
- Proposed hydro-electric development on the west branch of the Penobscot River in Maine
- Creator
- Walsh, Raymond L., Ehrman, Joseph S., Lill, Arthur C.
- Date
- 2009, 1913
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/proposedhydroele00wals
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 41
- Title
- Proposed hydro-electric development on North Platte River, Wyoming
- Creator
- Abrahamson, O. F., Armstrong, R. C., Armstrong, G., Graham, F. A.
- Date
- 2009, 1912
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/proposedhydroele00abra
Thesis (B.S.)--Armour Institute of Technology;Bibliography : leaf 63
- Title
- Proposed hydroelectric development on the west branch of the Penobscot River, Maine
- Creator
- Cooney, James G., Simpson, Herman N, Kinnally, Raymond W.
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/proposedhydroele00coon
Thesis (B.S.)--Armour Institute of Technology; Includes folded leaves in back pocket
- Title
- Proposed electrification of the Milwaukee branch, Chicago & Northwestern railway
- Creator
- Case, H. L., Fernandez-mareque, F., Schoembs, F., Whitmore, R. W.
- Date
- 2009, 1914
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/proposedelectrif00case
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 38 Includes folded...
Show morehttp://www.archive.org/details/proposedelectrif00case
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 38 Includes folded leaves in back pocket
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- Title
- SECURITY-CONSTRAINED UNIT COMMITMENT WITH UNCERTAINTIES
- Creator
- Yao, Yiyun
- Date
- 2015, 2015-05
- Description
-
In the first part of this thesis, an adaptive robust optimization model is developed for the SCUC problem in presence of uncertain load and...
Show moreIn the first part of this thesis, an adaptive robust optimization model is developed for the SCUC problem in presence of uncertain load and wind power. The model aims to minimize the operation cost for the base case SCUC problem with forecasted load and wind power, and meanwhile guarantee that the robust solution can be adaptively and securely adjusted to respond to all possible uncertain load and wind power realizations. In addition, this model considers the correlations between different uncertainty factors to limit the level of conservatism. Benders decomposition is used to divide the original problem into a master UC problem and three subproblems for hourly network evaluation, identification of the worst uncertainty realization in terms of the highest minimum network violations, and feasibility check of the worst uncertainty realization. Numerical case studies on a six-bus system show the effectiveness of the adaptive robust SCUC for the secure and economic operation of power systems under uncertainties. In the second part of this thesis, a scenario based SCUC model is discussed, which considers an alternative ‗randomized‘ approach for dealing with uncertainties in the SCUC problem. The based case SCUC with forecasted wind power and load is solved firstly. Then a finite set of scenarios are sampled randomly to represent uncertain load and wind power. The initial dispatch is checked and corrective action is considered to satisfy uncertain load and wind power in simulated scenarios. Numerical case studies on a six-bus system are conducted to evaluate the performances of the scenario based SCUC method.
M.S. in Electrical Engineering, May 2015
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- Title
- NEW CLASS OF EMBEDDED SPACE TIME BLOCK CODE FOR MIMO WIRELESS COMMUNICATION SYSTEMS
- Creator
- Norouzi, Mandana
- Date
- 2015, 2015-12
- Description
-
In this thesis a new class of space time block codes is proposed. Space time code is one solution for the multipath fading communication...
Show moreIn this thesis a new class of space time block codes is proposed. Space time code is one solution for the multipath fading communication systems that limit the reliability and data rate of the communication link. By organizing multiple antennas at the transmitter and receiver, multipath fading can be turned into an advantage, allowing for greater reliability and higher data rates than would otherwise be possible. Without any extra cost of bandwidth, rate and reliability benefits can be achieved. Therefore, having multiple antenna technology is a foundation of current and future wireless systems. In space time coding information, symbols are encoded across two dimensions, the spatial dimension and the time dimension. Information that is transmitted corresponds to multiple antennas at the transmitter and to multiple signaling intervals. In this thesis, we consider the problem of designing a new class of linear space time block codes, in which the information symbols are linearly combined to form a twodimensional code matrix, wherein the rows of the code word matrix correspond to transmission across multiple antennas, and the columns of the matrix correspond to transmission in different time slots. The proposed space time code matrix is achieved based on eigenvalue decomposition (EVD) of the circulant, normal matrix and inverse fast Fourier transform definition (IFFT). These classes of codes have better performance with respect to symbolerror rate (SER) in comparison with other proposed linear space time code matrices in the literature. The proposed code has full rate and embedded diversity. The concept of embedded diversity has been defined in this research. According to that definition ourdesign supports embedded diversity and also has less decoding complexity at the receiver side. The proposed code has been applied to a relay network where nodes do not have four transmit antennas. In this thesis, performance of the code has also been evaluated when the receiver must rely on a noisy, imperfect, estimate of the channel. Channel estimation has been applied based on pilot sequence transmission. A group decodable full rate and full diversity space time block code also has been proposed for two transmit antennas and four time slots, which is applicable to the LTE-Advanced system. This new design also provides full diversity and full rate.
Ph.D. in Electrical Engineering, December 2015
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- Title
- RADAR AND COMMUNICATION CO-DESIGN: A CONSTANT ENVELOPE RADCOM SYSTEM
- Creator
- Testi, Nicolo
- Date
- 2014, 2014-12
- Description
-
NO ABSTRACT
Ph.D. in Electrical and Computer Engineering, December 2014
- Title
- A new thermo-electric fluid-meter and hot-wire anemometer
- Creator
- Seyferlich, Walter M.
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/newthermoelectri00seyf
Thesis (B.S.)--Armour Institute of Technology
- Title
- ELECTRIC-HYDRAULIC HYBRID ENERGY STORAGE SYSTEM FOR ELECTRIFIED TRANSPORTATION
- Creator
- Niu, Geng
- Date
- 2017, 2017-07
- Description
-
Environmental issues and fossil fuel depletion push the evolution of transportation and electrified transportation into the most likely next...
Show moreEnvironmental issues and fossil fuel depletion push the evolution of transportation and electrified transportation into the most likely next generation. However, there are several challenges in electrification with the major concerns involving the energy storage system. A hybrid energy storage system may provide an opportunity to improve the energy storage system of applications in transportation electrification. Hydraulic systems have been a mature technology for a long time and this study proposes a hydraulic add-on for electric vehicles. The high power density of a hydraulic accumulator could absorb high frequency regenerative braking and support battery discharging during acceleration, which will extend the driving range and reduce the current stress of the battery pack. Several models and controls have been created to evaluate hydraulic add-ons in di↵erent applications. The simulation results show a roughly 30% current stress drop and up to 25% energy saving (Wh/km) on average for city buses and delivery trucks over di↵erent driving cycles. A scaled down prototype vehicle with a novel electric hydraulic hybrid powertrain based on a go-kart chassis was built to perform road tests to validate the simulations results.
Ph.D. in Electrical Engineering, July 2017
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- Title
- Researches in radio telephony
- Creator
- Petzing, Erwin Walter
- Date
- 2009, 1919
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/researchesinradi00petz
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 25
- Title
- SYSTEM-ON-CHIP FOR RESEARCH IN ULTRASOUNIC SIGNAL PROCESSING AND IMAGING APPLICATIONS
- Creator
- Gilliland, Spenser
- Date
- 2012-05-04, 2012-05
- Description
-
The Ultrasonic Signal Processing System-On-Chip (USPS) provides real-time signal analysis and image processing for the full range of...
Show moreThe Ultrasonic Signal Processing System-On-Chip (USPS) provides real-time signal analysis and image processing for the full range of ultrasound from 20 KHz to 20 MHz. The project aims to make it simple to effectively develop and implement algorithms in embedded software and reconfigurable hardware. This provides the user with an opportunity to explore the full design space including software only, hardware only, and hardware/software co-design. The USPS system provides high speed access to a 12-bit 250 MSPS Maxim MAX1215N ADC controlled by a Xilinx XC5VLX110T FPGA. Access to the ultrasound data and custom coprocessor cores is available through a gigabit Ethernet connection managed by an embedded Linux based operating system running on a Microblaze processor instantiated in the FPGA fabric.
M.S. in Computer Engineering, May 2012
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- Title
- MESH MODELING FOR SPATIALLY ADAPTIVE DENSITY MAPPING OF CRIME DATA
- Creator
- Ramon, Albert Juan
- Date
- 2015, 2015-05
- Description
-
As computing technology has become an essential tool for law enforcement, crime mapping has evolved from the use of pushpins on paper maps to...
Show moreAs computing technology has become an essential tool for law enforcement, crime mapping has evolved from the use of pushpins on paper maps to the use of computerized geographical information systems (GIS). The use of GIS permits real-time display of maps showing crime “hotspots,” facilitating the implementation of specific crime prevention strategies targeting the affected locations. Until recently, crime maps merely presented a summary of previous crime incidents; however, as part of a new concept called “predictive policing”, efforts are now underway to produce crime maps that are predictive, highlighting geographical regions that an algorithm determines are likely to experience abnormally high (or low) crime levels in the near future. Traditionally, crime maps are produced by representing crime data (a spatiotemporal point process) on a uniform grid, similar to the way in which pixels are used to represent digital images. However, the problem of predictive policing places new demands on mapping, raising questions about how maps should ideally be made. For example, there is considerable uncertainty concerning how best to optimize the grid spacing in a predictive map: If the pixels are too small, the past data required to predict future crime will be too sparse to enable good prediction performance; if the pixels are too large, each prediction will cover too large of a geographical region, the behavior of crime within the region may be heterogeneous and not well captured by a single predictive model, and coarse-scale predictions will not be sufficiently specific to be acted upon by police. In this thesis, a novel method for representing crime mapping data is proposed, in which the conventional pixel representation is replaced by a non-uniform sampling scheme based on mesh modeling, an approach that was first proposed in the context of image processing by members of our research group. In the present context, the goal is to adapt the spatial sampling to the local density of available training data in an effort to equalize prediction performance across a predictive map while accurately representing the spatial density. Geographical areas having few crimes will be represented more coarsely by this approach, with high-crime areas being represented at a fine spatial scale. We used various metrics to test the proposed approaches based on real and simulated crime-incident data for the City of Chicago. The results of our experiments demonstrate that the proposed method is a promising framework for predictive crime mapping. In future work, our hypothesis about the value of spatial sampling adaptation will be tested through the use of the proposed method within a complete spatio-temporal prediction algorithm. Although this thesis focuses only on representation of crime data, we anticipate that the proposed method may find application in other density estimation or mapping problems in which smooth densities are to be approximated from spatial point-process data.
M.S. in Electrical Engineering, May 2015
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- Title
- METHODS FOR CLASSIFICATION OF NOCTuRNAL MIGRATORY BIRD VOCALIZATIONS USING TIME-FREQUENCY REPRESENTATIONS
- Creator
- Patti, Anand
- Date
- 2012-07-30, 2012-07
- Description
-
Many species of birds in Americas vocalize during nocturnal migration ights. Acoustic detection and classi cation of the calls show potential...
Show moreMany species of birds in Americas vocalize during nocturnal migration ights. Acoustic detection and classi cation of the calls show potential for study of the nat- ural history of these migrant birds. In particular, information about the species' composition and number of birds involved in migration movements may be obtain- able through acoustic techniques. Other methods such as radar monitoring may have capability only to assess the number, but not the composition. Mel Frequency Cep- stral Coe cients-Gaussian Mixture Model-based methods, Mel Frequency Cepstral Coe cients-Hidden Markov Model-based methods and spectrogram correlation-based methods have been proposed to automate the recognition/classi cation of the noctur- nal ight calls. Here we investigate the impact of choice of time-frequency representa- tions on Mel Frequency Cepstral Coe cients-Hidden Markov Model-based classi er and correlation based classi er performance. We use a collection of recordings of nocturnal ight calls of several species of thrushes and other bird species with similar calls to evaluate and compare classi ers.
M.S. in Electrical Engineering, July 2012e
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- Title
- HYBRID BATTERY-ULTRACAPACITOR ENERGY STORAGE SYSTEMS FOR NEXT GENERATION SHIPBOARD POWER SYSTEMS
- Creator
- Tang, Yichao
- Date
- 2011-04-22, 2011-05
- Description
-
Batteries and ultracapacitors are likely to be candidates as excellent energy storage technologies for future shipboard power systems. This...
Show moreBatteries and ultracapacitors are likely to be candidates as excellent energy storage technologies for future shipboard power systems. This dissertation explores a hybrid Battery-Ultracapacitor Energy Storage System (BUCESS) for next generation shipboard application. Based on the power requirements of combat ships, a new configuration of the battery and ultracapacitor combined system is introduced for propulsion systems and pulse power loads. For one BUCESS unit, batteries and ultracapacitors are charged and discharged at high voltage level and high power level through a dual active bridge and a double-boost bidirectional converter. The converters are optimally designed to control the bidirectional power flow for batteries and ultracapacitors separately, and to ensure constant voltage regulation of ultracapacitors during charging and discharging. High-frequency switching devices are selected to achieve dc-dc conversion at high voltage and high power levels. The design guidelines and control schemes for simulations are provided for the proposed new topology. Finally, a double-input BUCESS unit is designed, analyzed and simulated to investigate different operation modes of the hybrid energy storage system.
M.S. in Electrical Engineering, May 2011
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- Title
- HIERARCHICAL SECURITY ARCHITECTURE FOR FUTURE NETWORKS
- Creator
- Pandirkar, Pravin C.
- Date
- 2012-07-16, 2012-07
- Description
-
A new mixed-initiative hierarchical framework of humans and agents that is well suited to protecting computational infrastructures. The...
Show moreA new mixed-initiative hierarchical framework of humans and agents that is well suited to protecting computational infrastructures. The framework, Cooperative Infrastructure Defense (CID), is designed to rapidly adapt to new cyber attacks via swarming software agents while enabling humans to supervise the system at an appropriate level. We interpose a hierarchy of rational software agents between the swarm and the human supervisors to provide a channel for system guidance and feedback. Using various kinds of rationality actually turns false positives into beneficial forms of positive feedback and improves system performance. CID represents a revolutionary new way of looking at system control for cyber security. Traditionally, humans control the entire system assisted by automated tools and subsystems. In CID, agents share the decision-making power, handling most of the real-time portion autonomously but enabling human involvement at all levels. The human supervisor does not directly control the system rather humans exert supervisory influence sharing the initiative for action with their software agents. CID is designed to be a scalable, dynamic, and robust framework for securing increasingly complex computational infrastructures.
M.S. in Electrical Engineering, July 2012
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- Title
- ADVANCED BASE DRIVERS FOR SILICON CARBIDE BJTs
- Creator
- Pozo Arribas, Alejandro
- Date
- 2017, 2017-07
- Description
-
This thesis focuses on the optimization of base drivers for SiC BJTs and presents a novel driver topology that targets minimum power...
Show moreThis thesis focuses on the optimization of base drivers for SiC BJTs and presents a novel driver topology that targets minimum power consumption. SiC BJTs have been studied for over a decade, during which time, they have been proven to have superior performance than Si IGBTs and even other normally-off SiC devices such as MOSFETs. Despite this, SiC BJTs are the least popular among the family of SiC power switches. As current controlled devices, BJTs require a continuous sup- ply of current through the base during the on-time. And, even though current gains over 100 have been reported, the base current required translates into a considerable amount power consumed by its driver, compared to its competitors. This power can affect the overall efficiency of a converter if the driver circuit is not designed properly. Since, the driver represents a key system for the success of SiC BJTs as power semiconductor devices, this thesis conducts a comprehensive evaluation of previous solutions and an analysis of the driver power losses to identify the optimal driver configuration. As a conclusion of this study, a novel topology is proposed, designed and built for its latter validation through experimental tests. The proposed solution allows the replacement of a SiC MOSFET or Si IGBT and driver with a SiC BJT and driver without the need of a current sensor or a dedicated DSP/FPGA. The driver power consumption is minimized with a proportional base current design based on a MHz synchronous buck converter operating as a Class D amplifier. This switched mode power amplifier uses a reference signal to provide a voltage that causes a base current proportional to the instantaneous collector current. The reference signal is generated with a high bandwidth sensor that measures the instantaneous voltage drop across the BJT (vCE) during the on-time. Hence, current sensors are avoided. Different alternatives for a voltage sensor are discussed and analyzed through simulations and experimental results. Moreover, the use of vCE to estimate the instantaneous collector current makes the proposed driver a temperature-sensitive design. For the first time, a proportional base current driver generates a base current proportional to the instantaneous collector current taking into account the effect of temperature on the DC current gain. Moreover, all this is achieved with solely analog electronics in a standalone solution. A 1.5kW Boost converter was built to validate the proposed driver under different collector currents and operating temperatures. In order to show the performance improvement offered by the proposed solution, the same Boost converter was operated with a commercial base current driver. This exercise showed a reduction of the driver power consumption by up to a factor of 4 without affecting the efficiency of the Boost converter. The switching behavior of a SiC BJT operated with the proposed driver and some of its limitations are discussed. These have, in fact, motivated additional research to develop efficient, isolated MHz regulators for faster operating frequencies of the SiC BJT. In addition, a new over-current protection integrated into the proposed driver is suggested and tested with interrupt times of less than 500ns for a collector current of 50A.
Ph.D. in Electrical Engineering, July 2017
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- Title
- A practical test of primary cells
- Creator
- Riker, A. C.
- Date
- 2009, 1909
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/practicaltestofp00rike
Thesis (B.S.)--Armour Institute of Technology
- Title
- SECURITY AND PERFORMANCE OPTIMIZATION FOR WIRELESS COMMUNICATIONS
- Creator
- Wang, Qian
- Date
- 2012-04-13, 2012-05
- Description
-
Today’s communication systems rely heavily on wireless technologies. The large scale proliferation of wireless technology brings with it a...
Show moreToday’s communication systems rely heavily on wireless technologies. The large scale proliferation of wireless technology brings with it a more serious concern for security since wireless communications introduce multiple avenues for attack and penetration into a network. This dissertation studies two important and fundamental problems in wireless communication security: secure secret key establishment and anti-jamming communication. This dissertation extends the current body of knowledge by proposing a suite of new and novel solutions to enhance and optimize the system performance. A comprehensive study including theoretical analysis and simulative evaluation shows that the proposed solutions can be applied in highly dynamic networking scenarios where traditional security mechanisms may not be sufficient by themselves. The first part of this dissertation develops a novel cooperative key generation protocol to facilitate high-rate key generation in narrowband fading channels, where two keying nodes extract the phase randomness of the fading channel with the aid of relay node(s). In particular, a theoretical upper bound and a more practical upper bound on the maximum secret key rate are successfully established. Numerical examples and simulation studies are also presented to demonstrate that the key rate can be improved by a couple of orders of magnitude compared to the existing physical layer based key generation approaches. The second part of this dissertation develops an adaptive uncoordinated frequency hopping (UFH) protocol for anti-jamming wireless communications. This section of the dissertation introduces the online optimization theory into the solution space and makes the thorough quantitative performance characterization possible for UFH-based anti-jamming communications. The optimality of the proposed algorithms is analytically proved under various message coding scenarios. Simulation results are presented demonstrating the jamming resilience of the learning-based UFH algorithm. The final part of this dissertation presents a jamming-resistant multi-radio multi-channel opportunistic spectrum access protocol for cognitive radio networks (CRNs), where the secondary sender and receiver adaptively choose their channels to operate to maximize the throughput. The convergence of the learning algorithm is investigated and an upper bound on the performance difference between the secondary sender and receiver’s optimal strategies is obtained. The simulation results in this section validate the theoretical analysis and show that even if facing a powerful jammer using myopic policy, the proposed design is still very effective and has strong resilience against jamming.
Ph.D. in Electrical Engineering, May 2012
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- Title
- Railway converter substation
- Creator
- Jacobson, Joseph H
- Date
- 1911
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/railwayconverter00jaco
Thesis (B.S.)--Armour Institute of Technology