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Articles 1 - 30 of 45
Full-Text Articles in Engineering
Effective Short Text Classification Via The Fusion Of Hybrid Features For Iot Social Data, Xiong Luo, Zhijian Yu, Zhigang Zhao, Wenbing Zhao, Jenq-Haur Wang
Effective Short Text Classification Via The Fusion Of Hybrid Features For Iot Social Data, Xiong Luo, Zhijian Yu, Zhigang Zhao, Wenbing Zhao, Jenq-Haur Wang
Electrical and Computer Engineering Faculty Publications
Nowadays short texts can be widely found in various social data in relation to the 5G-enabled Internet of Things (IoT). Short text classification is a challenging task due to its sparsity and the lack of context. Previous studies mainly tackle these problems by enhancing the semantic information or the statistical information individually. However, the improvement achieved by a single type of information is limited, while fusing various information may help to improve the classification accuracy more effectively. To fuse various information for short text classification, this article proposes a feature fusion method that integrates the statistical feature and the comprehensive …
Improving The Security Of Mobile Devices Through Multi-Dimensional And Analog Authentication, Jonathan Gurary
Improving The Security Of Mobile Devices Through Multi-Dimensional And Analog Authentication, Jonathan Gurary
ETD Archive
Mobile devices are ubiquitous in today's society, and the usage of these devices for secure tasks like corporate email, banking, and stock trading grows by the day. The first, and often only, defense against attackers who get physical access to the device is the lock screen: the authentication task required to gain access to the device. To date mobile devices have languished under insecure authentication scheme offerings like PINs, Pattern Unlock, and biometrics-- or slow offerings like alphanumeric passwords. This work addresses the design and creation of five proof-of-concept authentication schemes that seek to increase the security of mobile authentication …
Real-Time Assessment And Visual Feedback For Patient Rehabilitation Using Inertial Sensors, Deepa Adinarayanan
Real-Time Assessment And Visual Feedback For Patient Rehabilitation Using Inertial Sensors, Deepa Adinarayanan
ETD Archive
Rehabilitation exercises needs have been continuously increasing and have been projected to increase in future as well based on its demand for aging population, recovering from surgery, injury and illness and the living and working lifestyle of the people. This research aims to tackle one of the most critical issues faced by the exercise administers-Adherence or Non-Adherence to Home Exercise problems especially has been a significant issue resulting in extensive research on the psychological analysis of people involved. In this research, a solution is provided to increase the adherence of such programs through an automated real-time assessment with constant visual …
Continuous Human Activity Tracking Over A Large Area With Multiple Kinect Sensors, Akshat C. Hans
Continuous Human Activity Tracking Over A Large Area With Multiple Kinect Sensors, Akshat C. Hans
ETD Archive
In recent years, researchers had been inquisitive about the use of technology to enhance the healthcare and wellness of patients with dementia. Dementia symptoms are associated with the decline in thinking skills and memory severe enough to reduce a person’s ability to pay attention and perform daily activities. Progression of dementia can be assessed by monitoring the daily activities of the patients. This thesis encompasses continuous localization and behavioral analysis of patient’s motion pattern over a wide area indoor living space using multiple calibrated Kinect sensors connected over the network. The skeleton data from all the sensor is transferred to …
From Blockchain To Internet-Based Voting, Elham Akbari
From Blockchain To Internet-Based Voting, Elham Akbari
ETD Archive
Blockchain has been one of the hottest topics among the state-of-the-art technologies. As the enabling technology for Bitcoin, the pioneering cryptocurrency, blockchain is an append-only distributed ledger that is virtually impossible to attack. Hence, blockchain holds great promises as the fundamental technology to enable Internet-based electronic voting. However, Internet-based voting has additional requirements than what monetary transactions such as Bitcoin have to offer. In this thesis, we discuss the key differences of a blockchain-based voting system with digital currencies. In this context we also highlight the requirements, review existing proposed solutions, and outline possible improvements. Specifically, we propose several schemes …
Maintaining Parallel Realities In Cqrs And Event Sourcing, Ehren Thomas Eschmann
Maintaining Parallel Realities In Cqrs And Event Sourcing, Ehren Thomas Eschmann
ETD Archive
In today’s distributed software ecosystem, we have witnessed a broad exhibition of notable approaches to software architecture. Traditionally, these approaches have centered around persisting a system’s current state. Rather than adhere to these criteria, two modern architectures, Command Query Responsibility Segregation (CQRS) and Event Sourcing have inspired us to persist the interactions of the software actor as replayable events which describe the history of their input data.
While CQRS and Event Sourcing allow for considerable benefits in many types of
systems, maintaining parallel realities (multiple snapshots of history deriving from a single parent history) is generally regarded as too complex …
How Much A Quarter Cost: Allegory Of A Coin And Other Stories, Grant C. Gallo
How Much A Quarter Cost: Allegory Of A Coin And Other Stories, Grant C. Gallo
The Downtown Review
The philosophical theories of Baruch Spinoza and George Berkley were described, compared, and contrasted. Various examples and metaphors were used to help fully illustrate their respective metaphysical, epistemological, and ethical positions. The relevance of their theories to current philosophical discourse was discussed; showing that even in today’s technologically advanced society, seemingly antiquated ideas may still provide useful knowledge. In the end, Spinoza and Berkley’s apparently conflicting paradigms are rectified through a multiplexual, relativistic lens.
Intelligent Voice Activated Home Automation (Iva), Mrunal Dipakkumar Bhatt
Intelligent Voice Activated Home Automation (Iva), Mrunal Dipakkumar Bhatt
ETD Archive
This thesis presents the design of an original Intelligent Home Automation Architecture. My work was divided in two phases. The first portion was dedicated to acquiring a thorough understanding of the most successful and diffused Home-Automation commercial architectures. During this phase, I intended to gain a deep appreciation for the variety of organizations, capabilities, limitations, and potential areas of growth of the existing Home-Automation leading systems. In order to acquire this knowledge, I had to use a reverse engineering approach. The reason for using this methodology arises from the fact that all the products considered in this study are commercially …
Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel J. Simon, William A. Smith, Sergey Samorezov
Dynamic Modeling, Parameter Estimation And Control Of A Leg Prosthesis Test Robot, Hanz Richter, Daniel J. Simon, William A. Smith, Sergey Samorezov
Electrical and Computer Engineering Faculty Publications
Robotic testing can facilitate the development of new concepts, designs and control systems for prosthetic limbs. Human subject test clearances, safety and the lack of repeatability associated with human trials can be reduced or eliminated with automated testing, and test modalities are possible which are dangerous or inconvenient to attempt with patients. This paper describes the development, modeling, parameter estimation and control of a robot capable of reproducing two degree-of-freedom hip motion in the sagittal plane. Hip vertical displacement and thigh angle motion profiles are applied to a transfemoral prosthesis attached to the robot. A treadmill is used as walking …
An Autonomous Robotic Indoor Environment Surveillance System, Andrew Gunnerson, Bogdan Olar, Haodong Wang
An Autonomous Robotic Indoor Environment Surveillance System, Andrew Gunnerson, Bogdan Olar, Haodong Wang
Undergraduate Research Posters 2014
We developed an autonomous mobile robot platform capable of following a path and gather environmental data, including temperature, humidity, light intensity, etc. The robot is capable of detecting the path using its camera and correct most navigational errors, while the sensors support a limited set of instructions regarding which sensor data to collect and how often. Our experiment consisted of having the robot follow a looped path we set up in BU004 Lab. The robot was able to complete the loop and gather sensor data for light intensity, humidity and temperature at a frequency of once per second, and also …
Semiactive Virtual Control Method For Robots With Regenerative Energy-Storing Joints, Hanz Richter, Daniel J. Simon, Antonie J. Van Den Bogert
Semiactive Virtual Control Method For Robots With Regenerative Energy-Storing Joints, Hanz Richter, Daniel J. Simon, Antonie J. Van Den Bogert
Mechanical Engineering Faculty Publications
A framework for modeling and control is introduced for robotic manipulators with a number of energetically self-contained semiactive joints. The control approach consists of three steps. First, a virtual control design is conducted by any suitable means, assuming a fully-actuated system. Then, virtual control inputs are matched by a parameter modulation law. Finally, the storage dynamics are shaped using design parameters. Storage dynamics coincide with the system's internal dynamics under exact virtual control matching. An internal energy balance equation and associated self-powered operation condition are given for the semiactive joints. This condition is a structural characteristic of the system and …
Cache Invalidation Strategies For Internet-Based Vehicular Ad Hoc Networks, Sunho Lim, Chansu Yu, Chita R. Das
Cache Invalidation Strategies For Internet-Based Vehicular Ad Hoc Networks, Sunho Lim, Chansu Yu, Chita R. Das
Electrical and Computer Engineering Faculty Publications
Internet-based vehicular ad hoc network (Ivanet) is an emerging technique that combines a wired Internet and a vehicular ad hoc network (Vanet) for developing an ubiquitous communication infrastructure and improving universal information and service accessibility. A key design optimization technique in Ivanets is to cache the frequently accessed data items in a local storage of vehicles. Since vehicles are not critically limited by the storage/memory space and power consumption, selecting proper data items for caching is not very critical. Rather, an important design issue is how to keep the cached copies valid when the original data items are updated. This …
Many-To-One Communication Protocol For Wireless Sensor Networks, Chansu Yu, Robert Fiske, Seungmin Park, Won-Tae Kim
Many-To-One Communication Protocol For Wireless Sensor Networks, Chansu Yu, Robert Fiske, Seungmin Park, Won-Tae Kim
Electrical and Computer Engineering Faculty Publications
This paper proposes a novel communication protocol, called Many-to-One Sensors-to-Sink (MOSS), tailored to wireless sensor networks (WSNs). It exploits the unique sensors-to-sink traffic pattern to realize low-overhead medium access and low- latency sensors-to-sink routing paths. In conventional schedule-based MAC protocols such as S-MAC, sensor nodes in the proximity of the event generate reports simultaneously, causing unreliable and unpredictable performance during a brief but critical period of time when an event of interest occurs. MOSS is based on time division multiple access (TDMA) that avoids energy waste due to collisions, idle listening and overhearing and avoids unreliable behavior mentioned above. A …
Fuzzy Robot Controller Tuning With Biogeography-Based Optimization, George Thomas, Paul Lozovyy, Daniel J. Simon
Fuzzy Robot Controller Tuning With Biogeography-Based Optimization, George Thomas, Paul Lozovyy, Daniel J. Simon
Electrical and Computer Engineering Faculty Publications
Biogeography-based optimization (BBO) is an evolutionary algorithm (EA) based upon the models of biogeography, which describe the relationship between habitat suitability and the migration of species across habitats. In this work, we apply BBO to the problem of tuning the fuzzy tracking controller of mobile robots. This is an extension of previous work, in which we used BBO to tune a proportional-derivative (PD) controller for these robots. We show that BBO can successfully tune the shape of membership functions for a fuzzy controller with both simulation and real world experimental results.
Design And Implementation Of A Byzantine Fault Tolerance Framework For Non-Deterministic Applications, H. Zhang, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith
Design And Implementation Of A Byzantine Fault Tolerance Framework For Non-Deterministic Applications, H. Zhang, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith
Electrical and Computer Engineering Faculty Publications
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.
Behavior-Based Mobility Prediction For Seamless Handoffs In Mobile Wireless Networks, Weetit Wanalertlak, Ben Lee, Chansu Yu, Myungchul Kim, Seung-Min Park, Won-Tae Kim
Behavior-Based Mobility Prediction For Seamless Handoffs In Mobile Wireless Networks, Weetit Wanalertlak, Ben Lee, Chansu Yu, Myungchul Kim, Seung-Min Park, Won-Tae Kim
Electrical and Computer Engineering Faculty Publications
The field of wireless networking has received unprecedented attention from the research community during the last decade due to its great potential to create new horizons for communicating beyond the Internet. Wireless LANs (WLANs) based on the IEEE 802.11 standard have become prevalent in public as well as residential areas, and their importance as an enabling technology will continue to grow for future pervasive computing applications. However, as their scale and complexity continue to grow, reducing handoff latency is particularly important. This paper presents the Behavior-based Mobility Prediction scheme to eliminate the scanning overhead incurred in IEEE 802.11 networks. This …
A Cooperative Diversity-Based Robust Mac Protocol In Wireless Ad Hoc Networks, Sangman Moh, Chansu Yu
A Cooperative Diversity-Based Robust Mac Protocol In Wireless Ad Hoc Networks, Sangman Moh, Chansu Yu
Electrical and Computer Engineering Faculty Publications
In interference-rich and noisy environment, wireless communication is often hampered by unreliable communication links. Recently, there has been active research on cooperative communication that improves the communication reliability by having a collection of radio terminals transmit signals in a cooperative way. This paper proposes a medium access control (MAC) algorithm, called Cooperative Diversity MAC (CD-MAC), which exploits the cooperative communication capability of the physical (PHY) layer to improve robustness in wireless ad hoc networks. In CD-MAC, each terminal proactively selects a partner for cooperation and lets it transmit simultaneously so that this mitigates interference from nearby terminals, and thus, improves …
Robotic Testing Of Proximal Tibio-Fibular Joint Kinematics For Measuring Instability Following Total Knee Arthroplasty, Wael K. Barsoum, Ho H. Lee, Trevor G. Murray, Robb Colbrunn, Alison K. Klika, S. Butler, Antonie J. Van Den Bogert
Robotic Testing Of Proximal Tibio-Fibular Joint Kinematics For Measuring Instability Following Total Knee Arthroplasty, Wael K. Barsoum, Ho H. Lee, Trevor G. Murray, Robb Colbrunn, Alison K. Klika, S. Butler, Antonie J. Van Den Bogert
Mechanical Engineering Faculty Publications
Pain secondary to instability in total knee arthroplasty (TKA) has been shown to be major cause of early failure. In this study, we focused on the effect of instability in TKA on the proximal tibio-fibular joint (PTFJ). We used a robotics model to compare the biomechanics of the PTFJ in the native knee, an appropriately balanced TKA, and an unbalanced TKA. The tibia (n = 5) was mounted to a six-degree-of-freedom force/torque sensor and the femur was moved by a robotic manipulator. Motion at the PTFJ was recorded with a high-resolution digital camera system. After establishing a neutral position, …
Adaptive Multicast On Mobile Ad Hoc Networks Using Tree-Based Meshes With Variable Density Of Redundant Paths, Sangman Moh, Sang Jun Lee, Chansu Yu
Adaptive Multicast On Mobile Ad Hoc Networks Using Tree-Based Meshes With Variable Density Of Redundant Paths, Sangman Moh, Sang Jun Lee, Chansu Yu
Electrical and Computer Engineering Faculty Publications
Multicasting has been extensively studied for mobile ad hoc networks (MANETs) because it is fundamental to many ad hoc network applications requiring close collaboration of multiple nodes in a group. A general approach is to construct an overlay structure such as multicast tree or mesh and to deliver a multicast packet to multiple receivers over the overlay structure. However, it either incurs a lot of overhead (multicast mesh) or performs poorly in terms of delivery ratio (multicast tree). This paper proposes an adaptive multicast scheme, called tree-based mesh with k-hop redundant paths (TBM k ), …
Design And Implementation Of A Byzantine Fault Tolerance Framework For Web Services, Wenbing Zhao
Design And Implementation Of A Byzantine Fault Tolerance Framework For Web Services, Wenbing Zhao
Electrical and Computer Engineering Faculty Publications
Many Web services are expected to run with high degree of security and dependability. To achieve this goal, it is essential to use a Web services compatible framework that tolerates not only crash faults, but Byzantine faults as well, due to the untrusted communication environment in which the Web services operate. In this paper, we describe the design and implementation of such a framework, called BFT-WS. BFT-WS is designed to operate on top of the standard SOAP messaging framework for maximum interoperability. It is implemented as a pluggable module within the Axis2 architecture, as such, it requires minimum changes …
Proactive Service Migration For Long-Running Byzantine Fault-Tolerant Systems, Wenbing Zhao, H. Zhang
Proactive Service Migration For Long-Running Byzantine Fault-Tolerant Systems, Wenbing Zhao, H. Zhang
Electrical and Computer Engineering Faculty Publications
A proactive recovery scheme based on service migration for long-running Byzantine fault-tolerant systems is described. Proactive recovery is an essential method for ensuring the long-term reliability of fault-tolerant systems that are under continuous threats from malicious adversaries. The primary benefit of our proactive recovery scheme is a reduced vulnerability window under normal operation. This is achieved in two ways. First, the time-consuming reboot step is removed from the critical path of proactive recovery. Second, the response time and the service migration latency are continuously profiled and an optimal service migration interval is dynamically determined during runtime based on the observed …
Minimizing Spatial And Time Reservation With Collision-Aware Dcf In Mobile Ad Hoc Networks, Lubo Song, Chansu Yu
Minimizing Spatial And Time Reservation With Collision-Aware Dcf In Mobile Ad Hoc Networks, Lubo Song, Chansu Yu
Electrical and Computer Engineering Faculty Publications
Carrier sensing is widely adopted in wireless communication to protect data transfers from collisions. For example, distributed coordination function (DCF) in IEEE 802.11 standard renders a node to defer its communication if it senses the medium busy. For the duration of deferment, each frame carries, in its MAC header, a 16-bit number in microseconds during which any overhearing node must defer. However, even if the carrier signal is detected, both ongoing and a new communication can be simultaneously successful depending on their relative positions in the network or equivalently, their mutual interference level. Supporting multiple concurrent communications is …
A Reservation-Based Extended Transaction Protocol, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith
A Reservation-Based Extended Transaction Protocol, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith
Electrical and Computer Engineering Faculty Publications
With the advent of the new generation of Internet-based technology, in particular, web services, the automation of business activities that are distributed across multiple enterprises becomes possible. Business activities are different from traditional transactions in that they are typically asynchronous, loosely coupled, and long running. Therefore, extended transaction protocols are needed to coordinate business activities that span multiple enterprises. Existing extended transaction protocols typically rely on compensating transactions to handle exceptional conditions. In this paper, we identify a number of issues with compensation-based extended transaction protocols and describe a reservation-based extended transaction protocol that addresses those issues. Moreover, we define …
Real-Time On-Line Space Research Laboratory Environment Monitoring With Off-Line Trend And Prediction Analysis, Kenol Jules, Paul P. Lin
Real-Time On-Line Space Research Laboratory Environment Monitoring With Off-Line Trend And Prediction Analysis, Kenol Jules, Paul P. Lin
Mechanical Engineering Faculty Publications
With the International Space Station currently operational, a significant amount of acceleration data is being down-linked, processed and analyzed daily on the ground on a continuous basis for the space station reduced gravity environment characterization, the vehicle design requirements verification and science data collection. To help understand the impact of the unique spacecraft environment on the science data, an artificial intelligence monitoring system was developed, which detects in near real time any change in the reduced gravity environment susceptible to affect the on-going experiments. Using a dynamic graphical display, the monitoring system allows science teams, at any time and any …
Maximizing Communication Concurrency Via Link-Layer Packet Salvaging In Mobile Ad Hoc Networks, Chansu Yu, Kang G. Shin, Lubo Song
Maximizing Communication Concurrency Via Link-Layer Packet Salvaging In Mobile Ad Hoc Networks, Chansu Yu, Kang G. Shin, Lubo Song
Electrical and Computer Engineering Faculty Publications
Carrier-sense medium access control (MAC) protocols such as the IEEE 802.11 distributed coordination function (DCF) avoid collisions by holding up pending packet transmission requests when a carrier signal is observed above a certain threshold. However, this often results in unnecessarily conservative communication, thus making it difficult to maximize the utilization of the spatial spectral resource. This paper shows that a higher aggregate throughput can be achieved by allowing more concurrent communications and adjusting the communication distance on the fly, which needs provisions for the following two areas. On the one hand, carrier sense-based MAC protocols do not allow aggressive communication …
Byzantine Fault Tolerant Coordination For Web Services Atomic Transactions, Wenbing Zhao
Byzantine Fault Tolerant Coordination For Web Services Atomic Transactions, Wenbing Zhao
Electrical and Computer Engineering Faculty Publications
In this paper, we present the mechanisms needed for Byzantine fault tolerant coordination of Web services atomic transactions. The mechanisms have been incorporated into an open-source framework implementing the standard Web services atomic transactions specification. The core services of the framework, namely, the activation service, the registration service, the completion service, and the distributed commit service, are replicated and protected with our Byzantine fault tolerance mechanisms. Such a framework can be useful for many transactional Web services that require high degree of security and dependability.
End-To-End Latency Of A Fault-Tolerant Corba Infrastructure, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith
End-To-End Latency Of A Fault-Tolerant Corba Infrastructure, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith
Electrical and Computer Engineering Faculty Publications
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 …
H-Infinity Estimation For Fuzzy Membership Function Optimization, Daniel J. Simon
H-Infinity Estimation For Fuzzy Membership Function Optimization, Daniel J. Simon
Electrical and Computer Engineering Faculty Publications
Given a fuzzy logic system, how can we determine the membership functions that will result in the best performance? If we constrain the membership functions to a specific shape (e.g., triangles or trapezoids) then each membership function can be parameterized by a few variables and the membership optimization problem can be reduced to a parameter optimization problem. The parameter optimization problem can then be formulated as a nonlinear filtering problem. In this paper we solve the nonlinear filtering problem using H∞ state estimation theory. However, the membership functions that result from this approach are not (in general) sum normal. …
Dynamic Voltage Scaling Techniques For Power Efficient Video Decoding, Ben Lee, Eriko Nurvitadhi, Reshma Dixit, Chansu Yu, Myungchul Kim
Dynamic Voltage Scaling Techniques For Power Efficient Video Decoding, Ben Lee, Eriko Nurvitadhi, Reshma Dixit, Chansu Yu, Myungchul Kim
Electrical and Computer Engineering Faculty Publications
This paper presents a comparison of power-aware video decoding techniques that utilize dynamic voltage scaling (DVS). These techniques reduce the power consumption of a processor by exploiting high frame variability within a video stream. This is done through scaling of the voltage and frequency of the processor during the video decoding process. However, DVS causes frame deadline misses due to inaccuracies in decoding time predictions and granularity of processor settings used. Four techniques were simulated and compared in terms of power consumption, accuracy, and deadline misses. In addition, this paper proposes the frame-data computation aware (FDCA) technique, which is …
Unification Of Transactions And Replication In Three-Tier Architectures Based On Corba, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith
Unification Of Transactions And Replication In Three-Tier Architectures Based On Corba, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith
Electrical and Computer Engineering Faculty Publications
In this paper, we describe a software infrastructure that unifies transactions and replication in three-tier architectures and provides data consistency and high availability for enterprise applications. The infrastructure uses transactions based on the CORBA object transaction service to protect the application data in databases on stable storage, using a roll-backward recovery strategy, and replication based on the fault tolerant CORBA standard to protect the middle-tier servers, using a roll-forward recovery strategy. The infrastructure replicates the middle-tier servers to protect the application business logic processing. In addition, it replicates the transaction coordinator, which renders the two-phase commit protocol nonblocking and, thus, …