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Computer Engineering Commons

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2010

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Articles 1 - 30 of 705

Full-Text Articles in Computer Engineering

Regulatory Conformance Checking: Logic And Logical Form, Nikhil Dinesh Dec 2010

Regulatory Conformance Checking: Logic And Logical Form, Nikhil Dinesh

Publicly Accessible Penn Dissertations

We consider the problem of checking whether an organization conforms to a body of regulation. Conformance is studied in a runtime verification setting. The regulation is translated to a logic, from which we synthesize monitors. The monitors are evaluated as the state of an organization evolves over time, raising an alarm if a violation is detected. An important challenge to this approach comes from the fact that regulations are commonly expressed in natural language. The translation to logic is difficult. Our goal is to assist in this translation by: (a) the design of logics that let us formalize regulation one ...


Mechanisms For Unbounded, Conflict-Robust Hardware Transactional Memory, Colin Blundell Dec 2010

Mechanisms For Unbounded, Conflict-Robust Hardware Transactional Memory, Colin Blundell

Publicly Accessible Penn Dissertations

Conventional lock implementations serialize access to critical sections guarded by the same lock, presenting programmers with a difficult tradeoff between granularity of synchronization and amount of parallelism realized. Recently, researchers have been investigating an emerging synchronization mechanism called transactional memory as an alternative to such conventional lock-based synchronization. Memory transactions have the semantics of executing in isolation from one another while in reality executing speculatively in parallel, aborting when necessary to maintain the appearance of isolation. This combination of coarse-grained isolation and optimistic parallelism has the potential to ease the tradeoff presented by lock-based programming.

This dissertation studies the hardware ...


Integrated Freestanding Single-Crystal Silicon Nanowires: Conductivity And Surface Treatment, Chung-Hoon Lee, Clark Ritz, Minghuang Huang, Michael Ziwisky, Robert Blise, Max Lagally Dec 2010

Integrated Freestanding Single-Crystal Silicon Nanowires: Conductivity And Surface Treatment, Chung-Hoon Lee, Clark Ritz, Minghuang Huang, Michael Ziwisky, Robert Blise, Max Lagally

Electrical and Computer Engineering Faculty Research and Publications

Integrated freestanding single-crystal silicon nanowires with typical dimension of 100 nm × 100 nm × 5 µm are fabricated by conventional 1:1 optical lithography and wet chemical silicon etching. The fabrication procedure can lead to wafer-scale integration of silicon nanowires in arrays. The measured electrical transport characteristics of the silicon nanowires covered with/without SiO2 support a model of Fermi level pinning near the conduction band. The I–V curves of the nanowires reveal a current carrier polarity reversal depending on Si–SiO2 and Si–H bonds on the nanowire surfaces


Anonymous Query Processing In Road Networks, Kyriakos Mouratidis, Man Lung Yiu Dec 2010

Anonymous Query Processing In Road Networks, Kyriakos Mouratidis, Man Lung Yiu

Kyriakos MOURATIDIS

The increasing availability of location-aware mobile devices has given rise to a flurry of location-based services (LBSs). Due to the nature of spatial queries, an LBS needs the user position in order to process her requests. On the other hand, revealing exact user locations to a (potentially untrusted) LBS may pinpoint their identities and breach their privacy. To address this issue, spatial anonymity techniques obfuscate user locations, forwarding to the LBS a sufficiently large region instead. Existing methods explicitly target processing in the euclidean space and do not apply when proximity to the users is defined according to network distance ...


On-Line Discovery Of Hot Motion Paths, Dimitris Sacharidis, Kostas Patroumpas, Manolis Terrovitis, Verena Kantere, Michalis Potamias, Kyriakos Mouratidis, Timos Sellis Dec 2010

On-Line Discovery Of Hot Motion Paths, Dimitris Sacharidis, Kostas Patroumpas, Manolis Terrovitis, Verena Kantere, Michalis Potamias, Kyriakos Mouratidis, Timos Sellis

Kyriakos MOURATIDIS

We consider an environment of numerous moving objects, equipped with location-sensing devices and capable of communicating with a central coordinator. In this setting, we investigate the problem of maintaining hot motion paths, i.e., routes frequently followed by multiple objects over the recent past. Motion paths approximate portions of objects' movement within a tolerance margin that depends on the uncertainty inherent in positional measurements. Discovery of hot motion paths is important to applications requiring classification/profiling based on monitored movement patterns, such as targeted advertising, resource allocation, etc. To achieve this goal, we delegate part of the path extraction process ...


Continuous Monitoring Of Spatial Queries In Wireless Broadcast Environments, Kyriakos Mouratidis, Spiridon Bakiras, Dimitris Papadias Dec 2010

Continuous Monitoring Of Spatial Queries In Wireless Broadcast Environments, Kyriakos Mouratidis, Spiridon Bakiras, Dimitris Papadias

Kyriakos MOURATIDIS

Wireless data broadcast is a promising technique for information dissemination that leverages the computational capabilities of the mobile devices in order to enhance the scalability of the system. Under this environment, the data are continuously broadcast by the server, interleaved with some indexing information for query processing. Clients may then tune in the broadcast channel and process their queries locally without contacting the server. Previous work on spatial query processing for wireless broadcast systems has only considered snapshot queries over static data. In this paper, we propose an air indexing framework that 1) outperforms the existing (i.e., snapshot) techniques ...


Optimal Matching Between Spatial Datasets Under Capacity Constraints, Hou U Leong, Kyriakos Mouratidis, Man Lung Yiu, Nikos Mamoulis Dec 2010

Optimal Matching Between Spatial Datasets Under Capacity Constraints, Hou U Leong, Kyriakos Mouratidis, Man Lung Yiu, Nikos Mamoulis

Kyriakos MOURATIDIS

Consider a set of customers (e.g., WiFi receivers) and a set of service providers (e.g., wireless access points), where each provider has a capacity and the quality of service offered to its customers is anti-proportional to their distance. The capacity constrained assignment (CCA) is a matching between the two sets such that (i) each customer is assigned to at most one provider, (ii) every provider serves no more customers than its capacity, (iii) the maximum possible number of customers are served, and (iv) the sum of Euclidean distances within the assigned provider-customer pairs is minimized. Although max-flow algorithms ...


Continuous Spatial Assignment Of Moving Users, Leong Hou U, Kyriakos Mouratidis, Nikos Mamoulis Dec 2010

Continuous Spatial Assignment Of Moving Users, Leong Hou U, Kyriakos Mouratidis, Nikos Mamoulis

Kyriakos MOURATIDIS

Consider a set of servers and a set of users, where each server has a coverage region (i.e., an area of service) and a capacity (i.e., a maximum number of users it can serve). Our task is to assign every user to one server subject to the coverage and capacity constraints. To offer the highest quality of service, we wish to minimize the average distance between users and their assigned server. This is an instance of a well-studied problem in operations research, termed optimal assignment. Even though there exist several solutions for the static case (where user locations ...


Shortest Path Computation On Air Indexes, Georgios Kellaris, Kyriakos Mouratidis Dec 2010

Shortest Path Computation On Air Indexes, Georgios Kellaris, Kyriakos Mouratidis

Kyriakos MOURATIDIS

Shortest path computation is one of the most common queries in location-based services that involve transportation net- works. Motivated by scalability challenges faced in the mo- bile network industry, we propose adopting the wireless broad- cast model for such location-dependent applications. In this model the data are continuously transmitted on the air, while clients listen to the broadcast and process their queries locally. Although spatial problems have been considered in this environment, there exists no study on shortest path queries in road networks. We develop the rst framework to compute shortest paths on the air, and demonstrate the practicality and ...


Preference Queries In Large Multi-Cost Transportation Networks, Kyriakos Mouratidis, Yimin Lin, Man Lung Yiu Dec 2010

Preference Queries In Large Multi-Cost Transportation Networks, Kyriakos Mouratidis, Yimin Lin, Man Lung Yiu

Kyriakos MOURATIDIS

Research on spatial network databases has so far considered that there is a single cost value associated with each road segment of the network. In most real-world situations, however, there may exist multiple cost types involved in transportation decision making. For example, the different costs of a road segment could be its Euclidean length, the driving time, the walking time, possible toll fee, etc. The relative significance of these cost types may vary from user to user. In this paper we consider such multi-cost transportation networks (MCN), where each edge (road segment) is associated with multiple cost values. We formulate ...


The Wireless Control Network: Synthesis And Robustness, Miroslav Pajic, Shreyas Sundaram, Jerome Le Ny, George J. Pappas, Rahul Mangharam Dec 2010

The Wireless Control Network: Synthesis And Robustness, Miroslav Pajic, Shreyas Sundaram, Jerome Le Ny, George J. Pappas, Rahul Mangharam

Real-Time and Embedded Systems Lab (mLAB)

We consider the problem of stabilizing a plant with a network of resource constrained wireless nodes. Traditional networked control schemes are designed with one of the nodes in the network acting as a dedicated controller, while the other nodes simply route information to and from the controller and the plant. We introduce the concept of a Wireless Control Network (WCN) where the entire network itself acts as the controller. Specifically, at each time-step, each node updates its internal state to be a linear combination of the states of the nodes in its neighborhood. We show that this causes the entire ...


The Wireless Control Network: Monitoring For Malicious Behavior, Shreyas Sundaram, Miroslav Pajic, Christoforos N. Hadjicostis, Rahul Mangharam, George J. Pappas Dec 2010

The Wireless Control Network: Monitoring For Malicious Behavior, Shreyas Sundaram, Miroslav Pajic, Christoforos N. Hadjicostis, Rahul Mangharam, George J. Pappas

Real-Time and Embedded Systems Lab (mLAB)

We consider the problem of stabilizing a plant with a network of resource constrained wireless nodes. In a companion paper, we developed a protocol where each node repeatedly transmits a linear combination of the values in its neighborhood. For certain topologies, we showed that these linear combinations can be designed so that the closed loop system is stable (i.e., the wireless network itself acts as a controller for the plant). In this paper, we design a Intrusion Detection System (IDS) for this control scheme, which observes the transmissions of certain nodes in the network and uses that information to ...


Testing Embedded System Applications, Tingting Yu Dec 2010

Testing Embedded System Applications, Tingting Yu

Computer Science and Engineering: Theses, Dissertations, and Student Research

Embedded systems are becoming increasingly ubiquitous, controlling a wide variety of popular and safety-critical devices. Testing is the most commonly used method for validating software systems, and effective testing techniques could be helpful for improving the dependability of these systems. However, there are challenges involved in developing such techniques. Embedded systems consist of layers of software – application layers utilize services provided by underlying system service and hardware support layers. A typical embedded application consists of multiple user tasks. Interactions between application layers and lower layers, and interactions between the various user tasks that are initiated by the application layer, can ...


Pre-Eruption Pressure, Temperature And Volatile Content Of Rhyolite Magma From The 1650 Ad Eruption Of Kolumbo Submarine Volcano, Greece, K. Cantner, S. Carey, H. Sigurdsson, G. Vougioukalakis, P. Nomikou, C. Roman, K. Bell, M. Alexandri Dec 2010

Pre-Eruption Pressure, Temperature And Volatile Content Of Rhyolite Magma From The 1650 Ad Eruption Of Kolumbo Submarine Volcano, Greece, K. Cantner, S. Carey, H. Sigurdsson, G. Vougioukalakis, P. Nomikou, C. Roman, K. Bell, M. Alexandri

Christopher N. Roman

Biotite-bearing, crystal-poor rhyolite magma was the predominant magma type discharged during the 1650 AD explosive eruption of Kolumbo submarine volcano, Greece. The eruption produced thick sequences of pumice deposits (~100 m) in the upper crater walls of the volcano, but also led to the formation of extensive pumice rafts that were dispersed throughout the southern Aegean Sea, and subaerial tephra fallout as far east as Turkey. Preliminary estimates of pre-eruption volatile contents have been determined using the volatile-by-difference method on plagioclase-hosted melt inclusions and yield an average value of 6.0 wt.%. This corresponds to a pre-eruption storage pressure of ...


Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa Dec 2010

Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa

UMSL Faculty Works

The evolution of networking technologies and portable devices has led users to expect connectivity anytime and everywhere. We have reached the point of seeing networking occur underwater, via aerial devices, and across space. While researchers push the true boundaries of networking to serve a wide range of environments, there is the challenge of providing robust network connectivity beyond the boundaries of the core internet, defined by fiber optics and well-organized backbones. As the internet edges expand, the expectation is that connectivity will be as good, in terms of high bandwidth and minimal interruption, as anywhere in the core. Such an ...


Adaptive Checkpointing For Master-Worker Style Parallelism (Extended Abstract), Gene D. Cooperman, Jason Ansel, Xiaoqin Ma Dec 2010

Adaptive Checkpointing For Master-Worker Style Parallelism (Extended Abstract), Gene D. Cooperman, Jason Ansel, Xiaoqin Ma

Gene D. Cooperman

No abstract provided.


Dmtcp: Transparent Checkpointing For Cluster Computations And The Desktop, Jason Ansel, Kapil Arya, Gene D. Cooperman Dec 2010

Dmtcp: Transparent Checkpointing For Cluster Computations And The Desktop, Jason Ansel, Kapil Arya, Gene D. Cooperman

Gene D. Cooperman

DMTCP (Distributed MultiThreaded CheckPointing) is a transparent user-level checkpointing package for distributed applications. Checkpointing and restart is demonstrated for a wide range of over 20 well known applications, including MATLAB, Python, TightVNC, MPICH2, OpenMPI, and runCMS. RunCMS runs as a 680 MB image in memory that includes 540 dynamic libraries, and is used for the CMS experiment of the Large Hadron Collider at CERN. DMTCP transparently checkpoints general cluster computations consisting of many nodes, processes, and threads; as well as typical desktop applications. On 128 distributed cores (32 nodes), checkpoint and restart times are typically 2 seconds, with negligible run-time ...


Network Security Toolkit Including Heuristic Solutions For Trust System Placement And Network Obfuscation, Gabriel H. Greve Dec 2010

Network Security Toolkit Including Heuristic Solutions For Trust System Placement And Network Obfuscation, Gabriel H. Greve

Theses and Dissertations

For Part I, a supervisory control and data acquisition (SCADA) network consists of a group stations and substations in a portion of the power grid. The use of Internet technology in SCADA communications as well as other factors has caused vulnerabilities. One idea to help mitigate this risk is to strategically place trust nodes to compartmentalize and secure the SCADA systems without disturbing its finely honed processes. The trust nodes combine firewall and intrusion detection technology to provide more secure communication. An optimal solution to this problem has already been developed using a mixed-integer linear programming model. Because the problem ...


Cloud Computing: Strategies For Cloud Computing Adoption, Faith J. Shimba Dec 2010

Cloud Computing: Strategies For Cloud Computing Adoption, Faith J. Shimba

Faith Joel Shimba

The advent of cloud computing in recent years has sparked an interest from different IT stakeholders. This is a result of the new economic model for the IT department that cloud computing promises. The model promises to remove the need for heavy investment for limited IT resources towards renting IT resources and paying based on usage. Although, the adoption of cloud computing promises various benefits to organizations, a successful adoption requires an understanding of different dynamics and expertise in diverse domains. Currently there are inadequate guidelines for adoption and this book proposes a roadmap for cloud computing adoption called ROCCA ...


A Comprehensive Analysis Of Lte Physical Layer, Fahimeh Rezaei Dec 2010

A Comprehensive Analysis Of Lte Physical Layer, Fahimeh Rezaei

Theses, Dissertations, & Student Research in Computer Electronics & Engineering

The 3rd Generation Partnership Project (3GPP) introduced Long Term Evolution (LTE) as the 3rd generation of mobile communication standards. LTE Release 8 describes a mobile communication standard which supports up to 300 Mbps of data transmission in downlink using the OFDM scheme as well as up to 75 Mbps throughput for uplink using the SC-FDMA modulation. In this thesis, an in-depth study of LTE performance based on Release 8 is conducted for uplink and downlink under different scenarios. The main objective of this study is to investigate a comprehensive analysis of physical layer throughput of LTE Release8 based on standard ...


Cross-Layer Optimized Wireless Multimedia Networking, Dalei Wu Dec 2010

Cross-Layer Optimized Wireless Multimedia Networking, Dalei Wu

Theses, Dissertations, & Student Research in Computer Electronics & Engineering

Multimedia communications, especially real-time video communications, is expected to be the major application of the next-generation wireless networks. However, bringing delay-sensitive and loss-tolerant multimedia services based on the current wireless Internet is a very challenging task. In this dissertation, we address cross-layer optimized wireless multimedia networking from both theoretical and practical perspectives. In the first part of the dissertation, we propose cross-layer optimization frameworks for real-time video communications over wireless networks, where the expected received video quality is adopted as the objective function. With the user-centric objective function, we first study content-aware video communications in single-hop wireless networks by exploring ...


Use Of Mobile Phone Computing For Development Of Student 21st Century Skills, Susan M. Merritt, R. Lara Lee Dec 2010

Use Of Mobile Phone Computing For Development Of Student 21st Century Skills, Susan M. Merritt, R. Lara Lee

Cornerstone 2 Reports : Community Outreach and Empowerment Through Service Learning and Volunteerism

Mobile phone computing enables immediate capture and transfer of data, images, notes and experiences from the field to a repository where retrieval, analysis, edits, aggregation, and further development are possible. Immediate findings and later results can be shared on the Web with local and global communities, and development of integrated service learning projects in concert with underserved communities is possible using this mode of information gathering and sharing.

Mobile phone computing incorporates moments when participants build tomorrow's skills while addressing today's learning goals. Use of digital tools and supporting resources bring real world problems into focus. Mobile phone ...


Increasing High School Stem Participation Through Robotics Training And Tournaments (Final Report), Richard Kline Dec 2010

Increasing High School Stem Participation Through Robotics Training And Tournaments (Final Report), Richard Kline

Cornerstone 2 Reports : Community Outreach and Empowerment Through Service Learning and Volunteerism

The overall goal of this project was to engage high school students in an exciting way to increase their interest in science and technology. We planned to accomplish this by making Pace University an official Affiliate Partner of the FIRST Tech Challenge (FTC) robotics competition, a fast-growing program with more than 1,100 participating teams in 2009-2010. In FTC, high-school age participants design, build, and program their own robots to enter into regional and national competitions. Building on the Seidenberg School’s past success as a partner to FIRST with its FIRST LEGO League program, we intended to organize, host ...


The Gel Documentation System: A Cornerstone To The Implementation Of The Introduction To Biotechnology And Introduction To Bioinformatics Cross-Disciplinary Course Series (Final Report), Marcy Kelly, Gregory Lampard, Constance Knapp Dec 2010

The Gel Documentation System: A Cornerstone To The Implementation Of The Introduction To Biotechnology And Introduction To Bioinformatics Cross-Disciplinary Course Series (Final Report), Marcy Kelly, Gregory Lampard, Constance Knapp

Cornerstone 3 Reports : Interdisciplinary Informatics

Our original goal was to offer Pace undergraduate students opportunities to be introduced to both Biotechnology and Computer Science as it relates to Bioinformatics. We proposed a two course series, offered to both computer science and biology students that will increase both biological and computer science literacy of our students. The two courses are Introduction to Biotechnology (BIO 372) and Introduction to Bioinformatics.


Security@Web: Teaching Security With Alignment In Trust On The Web (Final Report), Li-Chiou Chen, Mary Long Dec 2010

Security@Web: Teaching Security With Alignment In Trust On The Web (Final Report), Li-Chiou Chen, Mary Long

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.


Tuning Of Power System Stabilizers Using Particle Swarm Optimization With Passive Congregation, Mahdiyeh Eslami, Hussain Shareef, Azah Mohamed, S. P Ghoshal Dec 2010

Tuning Of Power System Stabilizers Using Particle Swarm Optimization With Passive Congregation, Mahdiyeh Eslami, Hussain Shareef, Azah Mohamed, S. P Ghoshal

Dr. Mahdiyeh Eslami (مهدیه اسلامی)

No abstract provided.


Multi-Threshold Cmos Circuit Design Methodology From 2d To 3d, Ross Josiah Thian Dec 2010

Multi-Threshold Cmos Circuit Design Methodology From 2d To 3d, Ross Josiah Thian

Theses and Dissertations

A new and exciting approach in digital IC design in order to accommodate the Moore's law is 3D chip stacking. Chip stacking offers more transistors per chip, reduced wire lengths, and increased memory access bandwidths. This thesis demonstrates that traditional 2D design flow can be adapted for 3D chip stacking. 3D chip stacking has a serious drawback: heat generation. Die-on-die architecture reduces exposed surface area for heat dissipation. In order to reduce heat generation, a low power technique named Multi-Threshold CMOS (MTCMOS) was incorporated in this work. MTCMOS required designing a power management unit (to control when and which ...


From Program Synthesis To Optimal Program Synthesis, Joaquin Reyna Dec 2010

Testing Shock Absorbers: Towards A Faster Parallelizable Algorithm, Christian Servin Dec 2010

Towards Optimal Placement Of Bio-Weapon Detectors, Chris Kiekintveld, Octavio Lerma Dec 2010