Engineering Commons^™

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

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

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 to objects, …

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 in …

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 are applicable …

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 are fixed), …

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

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 …

Testing Embedded System Applications, Tingting Yu

Department of Computer Science and Engineering: Dissertations, Theses, 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, …

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

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

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

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

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

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

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

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 …

Utilization Of Automated Gcc Optimization For Dual-Width Instruction Sets On The Arm Architecture, Shane Watson

Computer Engineering

One of the most important considerations in embedded systems is code size. This consideration is obviously imposed by external factors such as cost and physical space, but what it boils down to is that we want our devices to be as powerful as they can within a (typically limited) specific form factor. This limits the amount of space we have for memory and as such we should always be considering the code size of our application and making sure it’s as efficient as possible. We also then need to consider other factors such as performance and power consumption. This is …

Development Of A Cubesat Payload To Model Particle Dampening In Space: Design And Implementation Of Software For Cp7, Daniel Walker

Computer Engineering

The California Polytechnic State University CubeSat student research & development group, PolySat, is currently in a mature development stage of a single unit CubeSat designated CP7. The CP7 mission implements a scientific payload designed to characterize particle dampers in microgravity conditions. When subjected to vibration, the momentum exchanges and frictional forces of the particles create a damping effect that can be optimized to suit a number of applications over a broad frequency and amplitude range. In space based applications, particle dampers would serve as a robust and simple device to eliminate jitter in optical assemblies and other sensitive instrumentation. This …

Intelligent Planning And Assimilation Of Auv-Obtained Measurements Within A Roms-Based Ocean Modeling System, Benjamin J. Davini

Master's Theses

Efforts to learn more about the oceans that surround us have increased dramatically as the technological ability to do so grows. Autonomous Underwater Vehicles (AUVs) are one such technological advance. They allow for rapid deployment and can gather data quickly in places and ways that traditional measurement systems (bouys, profilers, etc.) cannot. A ROMS-based data assimilation method was developed that intelligently plans for and integrates AUV measurements with the goal of minimizing model standard deviation. An algorithm developed for this system is first described that optimizes paths for AUVs that seeks to improve the model by gathering data in high-interest …

Sports-Tool, Bryant Ung

Computer Science and Software Engineering

Creating events and finding people to play sports is a hard thing to do. The solution to this problem is to provide a web based interactive site that allows people to create and join different type of events and interact with each other by creating teams.

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.

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.

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, and run …

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 computing enables …

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.

Computing The Range Of Variance-To-Mean Ratio Under Interval And Fuzzy Uncertainty, Sio-Long Lo, Gang Xiang

Departmental Technical Reports (CS)

In many practical problems such as radar imaging, it is useful to compute the variance-to-mean ratio. The need is important because for the sum of k identical independent signal components, both the variance and the mean are multiplied by k, so this ratio is independent on k and thus, provides useful information about the components. In practice, we only know the samples values with uncertainty. It is therefore necessary to compute the variance-to-mean ratio under this uncertainty. In this paper, we present efficient algorithms for computing this ratio under interval and fuzzy uncertainty.

Mamdani Approach To Fuzzy Control, Logical Approach, What Else?, Samuel Bravo, Jaime Nava

Departmental Technical Reports (CS)

In fuzzy control, two approaches are mainly used: Mamdani's approach, in which we represent the knowledge base as a disjunction of statements Ai(x) & Bi(u) corresponding to individual rules, and logical approach, in which the knowledge base is represented as a conjunction of the rules themselves Ai(x) --> Bi(u). Both approaches are known not to be perfect, so a natural question arises: what other approaches are possible? In this paper, we describe all possible approaches; alternative approaches use an "exclusive or" operation and correspond, e.g., to the fuzzy transform idea.

Least Sensitive (Most Robust) Fuzzy "Exclusive Or" Operations, Jesus E. Hernandez, Jaime Nava

Departmental Technical Reports (CS)

In natural language, "or" sometimes means "inclusive or" and sometimes means "exclusive or". To adequately describe commonsense and expert knowledge, it is therefore important to have not only t-conorms describing fuzzy "inclusive or" operations, but also fuzzy "exclusive or" operations f(a,b). Since the degrees of certainty are only approximately defined, it is reasonable to require that the corresponding operation be the least sensitive to small changes in the inputs. In this paper, we show that the least sensitive fuzzy "exclusive or" operation has the form f(a,b)=min(max(a,b),max(1-a,1-b)).

Estimating Mean Under Interval Uncertainty And Variance Constraint, Ali Jalal-Kamali, Luc Longpre, Misha Kosheleva

Departmental Technical Reports (CS)

Towards Chemical Applications Of Dempster-Shafer-Type Approach: Case Of Variant Ligands, Jaime Nava

Departmental Technical Reports (CS)

Towards Optimal Sensor Placement In Multi-Zone Measurements, Octavio Lerma, Craig Tweedie, Vladik Kreinovich

Departmental Technical Reports (CS)

In multi-zone areas, where the boundaries change with time, it is desirable to place sensors in such a way that the boundary is covered at all times. In this paper, we describe the optimal sensor placement with this property. In this optimal placement, sensors are placed along a see-saw trajectory going between the current location of the boundary and its farthest future location.