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Full-Text Articles in Engineering

Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau Dec 2015

Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau

Shih-Fen Cheng

In this paper, we evaluate whether the robustness of a market mechanism that allocates complementary resources could be improved through the aggregation of time periods in which resources are consumed. In particular, we study a multi-round combinatorial auction that is built on a general equilibrium framework. We adopt the general equilibrium framework and the particular combinatorial auction design from the literature, and we investigate the benefits and the limitation of time-period aggregation when demand-side uncertainties are introduced. By using simulation experiments on a real-life resource allocation problem from a container port, we show that, under stochastic conditions, the performance variation …


Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau Dec 2015

Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau

Shih-Fen Cheng

In this paper, we evaluate whether the robustness of a market mechanism that allocates complementary resources could be improved through the aggregation of time periods in which resources are consumed. In particular, we study a multi-round combinatorial auction that is built on a general equilibrium framework. We adopt the general equilibrium framework and the particular combinatorial auction design from the literature, and we investigate the benefits and the limitation of time-period aggregation when demand-side uncertainties are introduced. By using simulation experiments on a real-life resource allocation problem from a container port, we show that, under stochastic conditions, the performance variation …


Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau Dec 2015

Robust Distributed Scheduling Via Time Period Aggregation, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau

Shih-Fen CHENG

In this paper, we evaluate whether the robustness of a market mechanism that allocates complementary resources could be improved through the aggregation of time periods in which resources are consumed. In particular, we study a multi-round combinatorial auction that is built on a general equilibrium framework. We adopt the general equilibrium framework and the particular combinatorial auction design from the literature, and we investigate the benefits and the limitation of time-period aggregation when demand-side uncertainties are introduced. By using simulation experiments on a real-life resource allocation problem from a container port, we show that, under stochastic conditions, the performance variation …


Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling Dec 2015

Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling

Tammy R Toscos

Enhanced access and continuity are key components of patient-centered care. Existing studies show that several interventions such as providing same day appointments, walk-in services, after-hours care, and group appointments, have been used to redesign the healthcare systems for improved access to primary care. However, an intervention focusing on a single component of care delivery (i.e. improving access to acute care) might have a negative impact other components of the system (i.e. reduced continuity of care for chronic patients). Therefore, primary care clinics should consider implementing multiple interventions tailored for their patient population needs. We collected rapid ethnography and observations to …


Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Cranor Dec 2015

Can Declared Strategy Voting Be An Effective Instrument For Group Decision-Making?, Lorrie Cranor

Lorrie F Cranor

The goal of this research is to determine whether declared strategy voting can be an effective tool for group decision-making. Declared strategy voting is a novel group decision-making procedure in which preference is specified using voting strategies - first-order mathematical functions that specify a choice in terms of zero or more parameters. This research will focus on refining the declared strategy voting concept, developing an accessible implementation of declared strategy voting that can be used for mock elections, assessing the potential impacts of declared strategy voting, and evaluating the effectiveness of declared strategy voting for group decision-making. This proposal describes …


Design And Implementation Of A Practical Security-Conscious Electronic Polling System, Lorrie Cranor, Ron Cytron Dec 2015

Design And Implementation Of A Practical Security-Conscious Electronic Polling System, Lorrie Cranor, Ron Cytron

Lorrie F Cranor

We present the design and implementation of Sensus, a practical, secure and private system for conducting surveys and elections over computer networks. Expanding on the work of Fujioka, Okamoto, and Ohta, Sensus uses blind signatures to ensure that only registered voters can vote and that each registered voter only votes once, while at the same time maintaining voters' privacy. Sensus allows voters to verify independently that their votes were counted correctly, and anonymously challenge the results should their votes be miscounted. We outline seven desirable properties of voting systems and show that Sensus satisfied these properties well, in some cases …


Projected Nesterov’S Proximal-Gradient Signal Recovery From Compressive Poisson Measurements, Renliang Gu, Aleksandar Dogandžić Nov 2015

Projected Nesterov’S Proximal-Gradient Signal Recovery From Compressive Poisson Measurements, Renliang Gu, Aleksandar Dogandžić

Aleksandar Dogandžić

We develop a projected Nesterov’s proximal-gradient (PNPG) scheme for reconstructing sparse signals from compressive Poisson-distributed measurements with the mean signal intensity that follows an affine model with known intercept. The objective function to be minimized is a sum of convex data fidelity (negative log-likelihood (NLL)) and regularization terms. We apply sparse signal regularization where the signal belongs to a nonempty closed convex set within the domain of the NLL and signal sparsity is imposed using total-variation (TV) penalty. We present analytical upper bounds on the regularization tuning constant. The proposed PNPG method employs projected Nesterov’s acceleration step, function restart, and …


Implementing And Testing A Novel Chaotic Cryptosystem, Samuel Jackson, Scott Kerlin, Jeremy Straub Oct 2015

Implementing And Testing A Novel Chaotic Cryptosystem, Samuel Jackson, Scott Kerlin, Jeremy Straub

Jeremy Straub

Cryptography in the domain of small satellites is a relatively new area of research. Compared to typical desktop computers, small satellites have limited bandwidth, processing power, and battery power. Many of the current encryption schemes were developed for desktop computers and servers, and as such may be unsuitable for small satellites. In addition, most cryptographic research in the domain of small satellites focuses on hardware solutions, which can be problematic given the limited space requirements of small satellites.

This paper investigates potential software solutions that could be used to encrypt and decrypt data on small satellites and other devices with …


Work Integrated Learning In Stem In Australian Universities: Final Report: Submitted To The Office Of The Chief Scientist, Daniel Edwards, Kate Perkins, Jacob Pearce, Jennifer Hong Sep 2015

Work Integrated Learning In Stem In Australian Universities: Final Report: Submitted To The Office Of The Chief Scientist, Daniel Edwards, Kate Perkins, Jacob Pearce, Jennifer Hong

Dr Daniel Edwards

The Australian Council for Educational Research (ACER) undertook this study for the Office of the Chief Scientist (OCS). It explores the practice and application of Work Integrated Learning (WIL) in STEM, with a particular focus on natural and physical sciences, information technology, and agriculture departments in Australian universities. The project involved a detailed ‘stocktake’ of WIL in practice in these disciplines, with collection of information by interview, survey instruments, consultation with stakeholders and literature reviews. Every university in Australia was visited as part of this project, with interviews and consultation sessions gathering insight from more than 120 academics and support …


Work Integrated Learning In Stem In Australian Universities: Final Report: Submitted To The Office Of The Chief Scientist, Daniel Edwards, Kate Perkins, Jacob Pearce, Jennifer Hong Sep 2015

Work Integrated Learning In Stem In Australian Universities: Final Report: Submitted To The Office Of The Chief Scientist, Daniel Edwards, Kate Perkins, Jacob Pearce, Jennifer Hong

Dr Jacob Pearce

The Australian Council for Educational Research (ACER) undertook this study for the Office of the Chief Scientist (OCS). It explores the practice and application of Work Integrated Learning (WIL) in STEM, with a particular focus on natural and physical sciences, information technology, and agriculture departments in Australian universities. The project involved a detailed ‘stocktake’ of WIL in practice in these disciplines, with collection of information by interview, survey instruments, consultation with stakeholders and literature reviews. Every university in Australia was visited as part of this project, with interviews and consultation sessions gathering insight from more than 120 academics and support …


An Intelligent Attitude Determination And Control System Concept For A Cubesat Class Spacecraft, Jeremy Straub Sep 2015

An Intelligent Attitude Determination And Control System Concept For A Cubesat Class Spacecraft, Jeremy Straub

Jeremy Straub

An attitude determination and control system (ADCS) is used to orient a spacecraft for a wide variety of purposes (e.g., to keep a camera facing Earth or orient the spacecraft for propulsion system use). The proposed intelligent ADCS has several key features: first, it can be used in multiple modes, spanning from passive stabilization of two axes and unconstrained spin on a third to three-axis full active stabilization. It also includes electromagnetic components to ‘dump’ spin from the reaction wheels. Second, the ADCS utilizes an incorporated autonomous control algorithm to characterize the effect of actuation of the system components and, …


Design And Implementation Of Satellite Software To Facilitate Future Cubesat Development, Timothy Whitney, Jeremy Straub, Ronald Marsh Sep 2015

Design And Implementation Of Satellite Software To Facilitate Future Cubesat Development, Timothy Whitney, Jeremy Straub, Ronald Marsh

Jeremy Straub

The OpenOrbiter project is a campus-wide effort at the University of North Dakota to design and build a low-cost CubeSat-class satellite. The intent is to create a publically- available framework that allows a spacecraft to be built with a parts cost of less than USD $5,000 (excluding mission payload-specific costs). This paper focuses on OpenOrbiter’s software system methodology and implementation.

Current work seeks to create a generalized framework that other CubeSat developers can use directly or alter to suit their mission needs. It discusses OpenOrbiter’s overall design goals with an emphasis on software design. The software architecture is divided into …


Software Metrics And Dashboard, Shilpika Shilpika, George K. Thiruvathukal, Saulo Aguiar, Konstantin Läufer, Nicholas J. Hayward Aug 2015

Software Metrics And Dashboard, Shilpika Shilpika, George K. Thiruvathukal, Saulo Aguiar, Konstantin Läufer, Nicholas J. Hayward

George K. Thiruvathukal

Software metrics are a critical tool which provide continuous insight to products and processes and help build reliable software in mission critical environments. Using software metrics we can perform calculations that help assess the effectiveness of the underlying software or process. The two types of metrics relevant to our work is complexity metrics and in-process metrics. Complexity metrics tend to focus on intrinsic code properties like code complexity. In-process metrics focus on a higher-level view of software quality, measuring information that can provide insight into the underlying software development process.

Our aim is to develop and evaluate a metrics dashboard …


Software Design For An Intelligent Attitude Determination And Control System, Matthew Russell, Jeremy Straub Aug 2015

Software Design For An Intelligent Attitude Determination And Control System, Matthew Russell, Jeremy Straub

Jeremy Straub

Space exploration and satellite missions often carry equipment that must be accurately pointed towards distant targets, therefore making an effective attitude determination and control system (ADCS) a vital component of almost every spacecraft. However, the effectiveness of the ADCS could decrease drastically if components shift during launch, degrade in efficiency over the course of the mission, or simply fail. Prior work [0] has presented a concept for a adaptive ADCS which can respond to changing spacecraft conditions and environmental factors. This poster presents an implementation for a lazy learning ADCS is presented that uses past maneuver data to construct and …


Testing A Novel Cryptosystem For Use In Securing Small Satellite Communications, Samuel Jackson, Scott Kerlin, Jeremy Straub Aug 2015

Testing A Novel Cryptosystem For Use In Securing Small Satellite Communications, Samuel Jackson, Scott Kerlin, Jeremy Straub

Jeremy Straub

Cryptography in the domain of Small Satellites is a topic of growing importance. While large satellites are likely to have the hardware requirements to run common cryptographic algorithms, small satellites are extremely limited in both hardware capabilities, which limits the speed and security of cryptosystems implemented in software, and available physical space, which limits the ability to include cryptosystems implemented in hardware. However, small satellites are growing in popularity, and as such securing communications becomes a necessity for some. The Department of Defense is exploring the possibility of using CubeSats, a type of small satellite, in their operations, as are …


Improving Satellite Security Through Incremental Anomaly Detection On Large, Static Datasets, Connor Hamlet, Matthew Russell, Jeremy Straub, Scott Kerlin Aug 2015

Improving Satellite Security Through Incremental Anomaly Detection On Large, Static Datasets, Connor Hamlet, Matthew Russell, Jeremy Straub, Scott Kerlin

Jeremy Straub

Anomaly detection is a widely used technique to detect system intrusions. Anomaly detection in Intrusion Detection and Prevent Systems (IDPS) works by establishing a baseline of normal behavior and classifying points that are at a farther distance away as outliers. The result is an “anomaly score”, or how much a point is an outlier. Recent work has been performed which has examined use of anomaly detection in data streams [1]. We propose a new incremental anomaly detection algorithm which is up to 57,000x faster than the non-incremental version while slightly sacrificing the accuracy of results. We conclude that our method …


Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito Jun 2015

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

Ole J Mengshoel

For unmanned aerial systems (UAS) to be successfully deployed and integrated within the national airspace, it is imperative that they possess the capability to effectively complete their missions without compromising the safety of other aircraft, as well as persons and property on the ground. This necessity creates a natural requirement for UAS that can respond to uncertain environmental conditions and emergent failures in real-time, with robustness and resilience close enough to those of manned systems. We introduce a system that meets this requirement with the design of a real-time onboard system health management (SHM) capability to continuously monitor sensors, software, …


Towards Synthesis Of Platform-Aware Attack-Resilient Control Systems: Extended Abstract, Miroslav Pajic, Nicola Bezzo, James Weimer, Rajeev Alur, Rahul Mangharam, Nathan Michael, George Pappas, Oleg Sokolsky, Paulo Tabuada, Stephanie Weirich, Insup Lee Jun 2015

Towards Synthesis Of Platform-Aware Attack-Resilient Control Systems: Extended Abstract, Miroslav Pajic, Nicola Bezzo, James Weimer, Rajeev Alur, Rahul Mangharam, Nathan Michael, George Pappas, Oleg Sokolsky, Paulo Tabuada, Stephanie Weirich, Insup Lee

Stephanie Weirich

No abstract provided.


Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich Jun 2015

Contracts Made Manifest, Michael Greenberg, Benjamin C. Pierce, Stephanie Weirich

Stephanie Weirich

Since Findler and Felleisen (Findler, R. B. & Felleisen, M. 2002) introduced higher-order contracts, many variants have been proposed. Broadly, these fall into two groups: some follow Findler and Felleisen (2002) in using latent contracts, purely dynamic checks that are transparent to the type system; others use manifest contracts, where refinement types record the most recent check that has been applied to each value. These two approaches are commonly assumed to be equivalent—different ways of implementing the same idea, one retaining a simple type system, and the other providing more static information. Our goal is to formalize and clarify this …


Combining Proofs And Programs In A Dependently Typed Language, Stephanie Weirich, Vilhelm Sjoberg, Chris Casinghino Jun 2015

Combining Proofs And Programs In A Dependently Typed Language, Stephanie Weirich, Vilhelm Sjoberg, Chris Casinghino

Stephanie Weirich

Most dependently-typed programming languages either require that all expressions terminate (e.g. Coq, Agda, and Epigram), or allow infinite loops but are inconsistent when viewed as logics (e.g. Haskell, ATS, mega). Here, we combine these two approaches into a single dependently-typed core language. The language is composed of two fragments that share a common syntax and overlapping semantics: a logic that guarantees total correctness, and a call-by-value programming language that guarantees type safety but not termination. The two fragments may interact: logical expressions may be used as programs; the logic may soundly reason about potentially nonterminating programs; programs can require logical …


Programming Up To Congruence (Extended Version), Vilhelm Sjoberg, Stephanie Weirich Jun 2015

Programming Up To Congruence (Extended Version), Vilhelm Sjoberg, Stephanie Weirich

Stephanie Weirich

This paper presents the design of ZOMBIE, a dependently-typed programming language that uses an adaptation of a congruence closure algorithm for proof and type inference. This algorithm allows the type checker to automatically use equality assumptions from the context when reasoning about equality. Most dependently typed languages automatically use equalities that follow from -reduction during type checking; however, such reasoning is incompatible with congruence closure. In contrast, ZOMBIE does not use automatic -reduction because types may contain potentially diverging terms. Therefore ZOMBIE provides a unique opportunity to explore an alternative definition of equivalence in dependently typed language design. Our work …


Closed Type Families With Overlapping Equations (Extended Version), Richard A. Eisenberg, Dimitrios Vytiniotis, Simon Peyton Jones, Stephanie Weirich Jun 2015

Closed Type Families With Overlapping Equations (Extended Version), Richard A. Eisenberg, Dimitrios Vytiniotis, Simon Peyton Jones, Stephanie Weirich

Stephanie Weirich

Open, type-level functions are a recent innovation in Haskell that move Haskell towards the expressiveness of dependent types, while retaining the look and feel of a practical programming language. This paper shows how to increase expressiveness still further, by adding closed type functions whose equations may overlap, and may have non-linear patterns over an open type universe. Although practically useful and simple to implement, these features go beyond conventional dependent type theory in some respects, and have a subtle metatheory.


Data Management In Cloud Environments: Nosql And Newsql Data Stores, Katarina Grolinger, Wilson A. Higashino, Abhinav Tiwari, Miriam Am Capretz May 2015

Data Management In Cloud Environments: Nosql And Newsql Data Stores, Katarina Grolinger, Wilson A. Higashino, Abhinav Tiwari, Miriam Am Capretz

Wilson A Higashino

: Advances in Web technology and the proliferation of mobile devices and sensors connected to the Internet have resulted in immense processing and storage requirements. Cloud computing has emerged as a paradigm that promises to meet these requirements. This work focuses on the storage aspect of cloud computing, specifically on data management in cloud environments. Traditional relational databases were designed in a different hardware and software era and are facing challenges in meeting the performance and scale requirements of Big Data. NoSQL and NewSQL data stores present themselves as alternatives that can handle huge volume of data. Because of the …


Supervisory Control And Data Acquisition (Scada) Control Optimization, Garrett Johnson, Jeremy Straub, Eunjin Kim Apr 2015

Supervisory Control And Data Acquisition (Scada) Control Optimization, Garrett Johnson, Jeremy Straub, Eunjin Kim

Jeremy Straub

SCADA systems are generally used to monitor and control multiple systems of the same type to allow them to be remotely controlled and monitored. Water plants, for example, could be controlled and monitored by a SCADA system. This project seeks to optimize a SCADA system using Artificial Intelligence. A constraint satisfaction / optimization algorithm is used to maximize performance relative to weighted system goals.


Scheduling Algorithm Development For An Open Source Software And Open Hardware Spacecraft, Calvin Bina, Jeremy Straub, Ronald Marsh Apr 2015

Scheduling Algorithm Development For An Open Source Software And Open Hardware Spacecraft, Calvin Bina, Jeremy Straub, Ronald Marsh

Jeremy Straub

The efficacy of each type of scheduler is assessed rela-tive to the goal of having a time and resource efficient scheduling algorithm. The scheduler must ensure suc-cessful spacecraft operations and maximize the perfor-mance of tasks relative to performance constraints and their respective due dates.


Assessment Of The Impact Of Clothing And Environmental Conditions On Visible Light 3d Scanning, Pann Ajjimaporn, Jeremy Straub, Scott Kerlin Apr 2015

Assessment Of The Impact Of Clothing And Environmental Conditions On Visible Light 3d Scanning, Pann Ajjimaporn, Jeremy Straub, Scott Kerlin

Jeremy Straub

The quality of models produced by visible light 3D scanners is influenced by multiple factors. To max-imize model accuracy and detail levels, the correct combination of lighting texture, subject posture and software usage must be selected. The work described herein has been performed to measure the effect of different lighting and envi-ronmental conditions on human 3D scanning results.


Scada System Security: Accounting For Operator Error And Malicious Intent, Ryan Kilbride, Jeremy Straub, Eunjin Kim Apr 2015

Scada System Security: Accounting For Operator Error And Malicious Intent, Ryan Kilbride, Jeremy Straub, Eunjin Kim

Jeremy Straub

Supervisory control and data acquisition (SCADA) systems are becoming more and more com-monplace in many industries today. Industries are making better use of software and large scale control systems to run efficiently, without the need for large amounts of oversight. Security is a particularly large issue with such systems, however. A human must still be involved to ensure smooth operation in the event of catastrophic system error, or unusual circumstanc-es. Human involvement presents problems: operators could make mistakes, configure the system to operate sub-optimally or take malicious actions. This imple-mentation of SCADA security aims to combat these problems.


Autonomous Navigation And Control Of Unmanned Aerial Systems In The National Airspace, Michael Hlas, Jeremy Straub, Eunjin Kim Apr 2015

Autonomous Navigation And Control Of Unmanned Aerial Systems In The National Airspace, Michael Hlas, Jeremy Straub, Eunjin Kim

Jeremy Straub

Pilotless aircraft known as Unmanned Aerial Vehicles (UAVs) have been used extensively for military and intelligence purposes. This includes situations where the mission area is too dangerous for a pilot to fly, the length of the mission is longer than a pilot could stay awake or aircraft are used as cruise missiles that crash into their target. With the decreasing cost and miniaturization of computers, it has become possible to build UAVs that are small and inexpensive making them accessible to businesses, law enforcement, hobbyists and the general public.


Pattern Recognition And Expert Systems For Microwave Wireless Power Transmission Failure Prevention, Cameron Kerbaugh, Allen Mcdermott, Jeremy Straub, Eunjin Kim Apr 2015

Pattern Recognition And Expert Systems For Microwave Wireless Power Transmission Failure Prevention, Cameron Kerbaugh, Allen Mcdermott, Jeremy Straub, Eunjin Kim

Jeremy Straub

Wireless power transfer (WPT) can be used to deliver space-generated power to ground stations through the use of microwave beams. WPT satellite power delivery systems have two major failure states: misdi-recting a beam and failing to send power to a station. This project has implemented an expert system to perform pattern recognition in an effort to prevent failures by analyzing the system state and predicting potential failures before they happen in support of space-based testing [1] and deployment [2].


Pattern Recognition For Detecting Failures In Space Solar Power Systems, Allen Mcdermott, Cameron Kerbaugh, Jeremy Straub, Eunjin Kim Apr 2015

Pattern Recognition For Detecting Failures In Space Solar Power Systems, Allen Mcdermott, Cameron Kerbaugh, Jeremy Straub, Eunjin Kim

Jeremy Straub

This poster covers work relating to the use of expert systems and pattern recognition to attempt to identify, detect and prospectively stop patterns of activity that could potentially lead to failure of a space solar power (SSP) system. A database-based expert system has is presented to identify patterns, which can be used to determine whether a power beam could hit a unintend- ed target and potentially cause a calamity. This has been implemented via a facts-rule network via which supplied and collected facts and a rule set is used to de- termine whether the system is operating correctly (from a …