Operations Research, Systems Engineering and Industrial Engineering Commons^™

Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy

Dr Deogratias Harorimana

ICT for Poverty Alleviation in Pacific Island Nations: Study of ICTs4D in Fiji There has been a vague and little knowledge on the role or potential of Information and Communications Technologies (ICTs) in relation to addressing poverty in Fiji. This may be probably due to the newness of the technology in the South Pacific Region as a whole but also probably due to the fact that only 9.7% of the current Fiji 931,000 populations are internet users (ITC Figures 2011). This paper reports on finding how ICTs is contributing towards poverty alleviation in Fiji. On the basis of reviewed best …

Cv, Elizabeth C. Scheyder

Elizabeth C Scheyder

CV, updated November 2012.

Conversations Around Design Sketches: Use Of Communication Channels For Sharing Mental Models During Concept Generation, Nik Shahman Nik Ahmad Ariff, Petra Badke-Schaub, Ozgur Eris

Ozgur Eris

In this paper, we present an exploratory protocol study on the use of different communication channels during design sketching. We focus on how individual designers share their mental models with other designers in a group, and analyse their use of graphical, textual, and verbal communications during concept generation.

Our findings suggest that verbal communication plays a role in the sharing of individual mental models during sketching, and complements graphical and textual communication channels. However, design teams can still function without verbal communication in that respect, and address design problems. They seem to compensate for the absence of the verbal communication …

Mle+: A Tool For Integrated Design And Deployment Of Energy Efficient Building Controls, Willy Bernal, Madhur Behl, Truong Nghiem, Rahul Mangharam

Madhur Behl

We present MLE+, a tool for energy-efficient building automation design, co-simulation and analysis. The tool leverages the high-fidelity building simulation capabilities of EnergyPlus and the scientific computation and design capabilities of Matlab for controller design. MLE+ facilitates integrated building simulation and controller formulation with integrated support for system identification, control design, optimization, simulation analysis and communication between software applications and building equipment. It provides streamlined workflows, a graphical front-end, and debugging support to help control engineers eliminate design and programming errors and take informed decisions early in the design stage, leading to fewer iterations in the building automation development cycle. …

An Alternative Characterization Of Robust Stability And Stability Radius For Linear Time Delay Systems, Bahram Shafai, Hanai Sadaka, Rifat Sipahi, Jie Chen

Bahram Shafai

No abstract provided.

An Alternative Characterization Of Robust Stability And Stability Radius For Linear Time Delay Systems, Bahram Shafai, Hanai Sadaka, Rifat Sipahi, Jie Chen

Hanai Sadaka

No abstract provided.

Minimization Of Costs In Interconnected Supply Networks With Transportation And Decision-Making Delays, Ilker I. Delice, Rifat Sipahi, Tucker J. Marion

Tucker Marion

No abstract provided.

Comparative Experiments With A New Adaptive Controller For Robot Arms, Louis L. Whitcomb, Daniel E. Koditschek, Alfred A. Rizzi

Daniel E Koditschek

This paper presents a new model-based adaptive controller and proof of its global asymptotic stability with respect to the standard rigid-body model of robot-arm dynamics. Experimental data from a study of one new and several established globally asymptotically stable adaptive controllers on two very different robot arms 1) demonstrate the superior tracking performance afforded by the model-based algorithms over conventional PD control, 2) demonstrate and compare the superior performance of adaptive model-based algorithms over their nonadaptive counterparts, 3) reconcile several previous contrasting empirical studies, and 4) examine contexts that compromise their advantage.

X-Rhex: A Highly Mobile Hexapedal Robot For Sensorimotor Tasks, Kevin C. Galloway, Galen Clark Haynes, B. Deniz Ilhan, Aaron M. Johnson, Ryan Knopf, Goran A. Lynch, Benjamin N. Plotnick, Mackenzie White, Daniel E. Koditschek

Daniel E Koditschek

We report on the design and development of X-RHex, a hexapedal robot with a single actuator per leg, intended for real-world mobile applications. X-RHex is an updated version of the RHex platform, designed to offer substantial improvements in power, run-time, payload size, durability, and terrain negotiation, with a smaller physical volume and a comparable footprint and weight. Furthermore, X-RHex is designed to be easier to build and maintain by using a variety of commercial off-the-shelf (COTS) components for a majority of its internals. This document describes the X-RHex architecture and design, with a particular focus on the new ability of …

A Framework For The Coordination Of Legged Robot Gaits, Joel D. Weingarten, Richard E. Groff, Daniel E. Koditschek

Daniel E Koditschek

This paper introduces a framework for representing, generating, and then tuning gaits of legged robots. We introduce a convenient parametrization of gait generators as dynamical systems possessing designer specified stable limit cycles over an appropriate torus. This parametrization affords a continuous selection of operation within a coordination design plane, inspired by biology, spanned by axes that determine the mix of "feedforward/feedback" and "centralized/decentralized" control. Tuning the gait generator parameters through repeated physical experiments with our robot hexapod, RHex, determines the appropriate operating point - the mix of feedback and degree of control decentralization - to achieve significantly increased performance relative …

Preliminary Analysis Of A Biologically Inspired 1-Dof "Clock" Stabilized Hopper, Haldun Komsuoglu, Daniel E. Koditschek

Daniel E Koditschek

We investigate the stability of a one degree of freedom mechanical spring-mass system modulated by a feed-forward "clock" that stiffens and relaxes a Hooke's law potential force according to a periodic rhythm. At the present early stage of inquiry, we offer sufficient conditions for local asymptotic stability of an isolated periodic orbit when there is no feedback to the clock at all but some viscous friction in the mechanism. We conjecture that, absent feedback, a lossless mechanical system cannot exhibit an asymptotically stable limit cycle in response to such rhythmic excitation.

A Brachiating Robot Controller, Jun Nakanishi, Toshio Fukuda, Daniel E. Koditschek

Daniel E Koditschek

We report on our empirical studies of a new controller for a two-link brachiating robot. Motivated by the pendulum-like motion of an ape's brachiation, we encode this task as the output of a "target dynamical system." Numerical simulations indicate that the resulting controller solves a number of brachiation problems that we term the "ladder," "swing-up," and "rope" problems. Preliminary analysis provides some explanation for this success. The proposed controller is implemented on a physical system in our laboratory. The robot achieves behaviors including "swing locomotion" and "swing up" and is capable of continuous locomotion over several rungs of a ladder. …

Optimal Paths In Weighted Timed Automata, Rajeev Alur, Salvatore La Torre, George J. Pappas

George J. Pappas

We consider the optimal-reachability problem for a timed automaton with respect to a linear cost function which results in a weighted timed automaton. Our solution to this optimization problem consists of reducing it to computing (parametric) shortest paths in a finite weighted directed graph. We call this graph a parametric sub-region graph. It refines the region graph, a standard tool for the analysis of timed automata, by adding the information which is relevant to solving the optimal-reachability problem. We present an algorithm to solve the optimal-reachability problem for weighted timed automata that takes time exponential in O(n (|δ(A)|+|wmax|)), where n …

Optimal Paths In Weighted Timed Automata, Rajeev Alur, Salvatore La Torre, George J. Pappas

George J. Pappas

We consider the optimal-reachability problem for a timed automaton with respect to a linear cost function which results in a weighted timed automaton. Our solution to this optimization problem consists of reducing it to computing (parametric) shortest paths in a finite weighted directed graph. We call this graph a parametric sub-region graph. It refines the region graph, a standard tool for the analysis of timed automata, by adding the information which is relevant to solving the optimal-reachability problem. We present an algorithm to solve the optimal-reachability problem for weighted timed automata that takes time exponential in O(n (|δ(A)|+|wmax|)), where n …

Optimal Paths In Weighted Timed Automata, Rajeev Alur, Salvatore La Torre, George J. Pappas

George J. Pappas

We consider the optimal-reachability problem for a timed automaton with respect to a linear cost function which results in a weighted timed automaton. Our solution to this optimization problem consists of reducing it to computing (parametric) shortest paths in a finite weighted directed graph. We call this graph a parametric sub-region graph. It refines the region graph, a standard tool for the analysis of timed automata, by adding the information which is relevant to solving the optimal-reachability problem. We present an algorithm to solve the optimal-reachability problem for weighted timed automata that takes time exponential in O(n (|δ(A)|+|wmax|)), where n …

Social Networks And Web2.0 Among Youth: Lessons For Pacific Island Nations, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This study is on social networks and web2 among youths and the lessons for Pacific Island nation. This study defines commonly used social networking sites used by the Pacific youths, average time spent, reasons behind the use of social networking sites and how social networking sites can be used as a development tool for Pacific Island nation. It was found that the popularity of social networking amongst youths in Pacific Island Countries is fast growing, increasing more than three folds year on year in the last 3years. Social Networks are a vital part of life for PIC youths, where, now …

Hydrogen Production From Biogas By Oxy-Reforming: Reaction System Analysis, Aleksandra Terlecka, Wojciech M. Budzianowski

Wojciech Budzianowski

Oxy-reforming is emerging as an interesting alternative to conventional methods of hydrogen generation. The current article characterises this process through analysis of individual reactions: SMR (steam methane reforming), WGS (water gas shift) and CPO (catalytic partial oxidation). Analyses relate to optimisation of thermal conditions thus enabling cost-effectivenes of the process.

Syllabus - Writ 150 - Writing In The Digital Age: Crafting Multimedia, Elizabeth C. Scheyder

Elizabeth C Scheyder

No abstract provided.