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2013

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Articles 31 - 60 of 381

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

In Situ Performance Of A Complex Urban Turnout Grillage System Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen Nov 2013

In Situ Performance Of A Complex Urban Turnout Grillage System Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen

Sakdirat Kaewunruen

A full-scale trial to investigate in-situ behaviours of a turnout grillage system using an alternative material, ‘fibre-reinforced foamed urethane (FFU)’ bearers, has been carried out at a complex turnout junction under heavy mixed traffics at Hornsby, New South Wales, Australia. The turnout junction was renewed using the FFU bearers altogether with new special track components. Influences of the FFU bearers on track geometry (recorded by track inspection vehicle ‘AK Car’ and based on survey data), track settlement, track dynamics and acoustic characteristics have been measured. Operational train pass-by measurements have been analysed to evaluate the effectiveness of the replacement methodology. …


Acuta Enews November 2013 Vol. 42, No. 11 Nov 2013

Acuta Enews November 2013 Vol. 42, No. 11

ACUTA Newsletters

In this Issue...

1 The Concept of Context-Aware Computing

2 Nominate Now for Ruth A. Michalecki Leadership Award

3 Collaboration Is Not Automatic

4 Nominations for Board of Directors: Deadline November 18

5 Free Webinar: The Evolution of Control Systems Security Brief

5 What's on Your Desk?

6 Bring 8 Fall Seminar Sessions to Your Desktop or Tablet

6 Thanks to Fall Seminar Exhibitors 6 Sponsors

6 Get Your Logos Here

7 Info Links

8 Add Names from Your Campus to Your ' ACUTA Roster

8 Board Report

9 Welcome New Members

9 Check It Out


Deployed Communications In An Austere Environment: A Delphi Study, Andrew Soine, James Harker, Alan R. Heminger Nov 2013

Deployed Communications In An Austere Environment: A Delphi Study, Andrew Soine, James Harker, Alan R. Heminger

Faculty Publications

The information and communications technology (ICT) field is undergoing a period of tremendous change. The exponential growth rate of ICT capability in recent decades, which has had an undeniable effect on every aspect of our society, will likely have ramifications for military operations in austere environments. 1 The Air Force’s 689th Combat Communications Wing commissioned a study to forecast the future of mobile ICT in such environments. Researchers at the Air Force Institute of Technology chose to employ the Delphi technique as the methodology for executing this task. The following scenario, based on the results of that study, demonstrates how …


Optimization Approaches For Solving Chance Constrained Stochastic Orienteering Problems, Pradeep Varakantham, Akshat Kumar Nov 2013

Optimization Approaches For Solving Chance Constrained Stochastic Orienteering Problems, Pradeep Varakantham, Akshat Kumar

Research Collection School Of Computing and Information Systems

Orienteering problems (OPs) are typically used to model routing and trip planning problems. OP is a variant of the well known traveling salesman problem where the goal is to compute the highest reward path that includes a subset of nodes and has an overall travel time less than the specified deadline. Stochastic orienteering problems (SOPs) extend OPs to account for uncertain travel times and are significantly harder to solve than deterministic OPs. In this paper, we contribute a scalable mixed integer LP formulation for solving risk aware SOPs, which is a principled approximation of the underlying stochastic optimization problem. Empirically, …


Budgeted Personalized Incentive Approaches For Smoothing Congestion In Resource Networks, Pradeep Varakantham, Na Fu, William Yeoh, Shih-Fen Cheng, Hoong Chuin Lau Nov 2013

Budgeted Personalized Incentive Approaches For Smoothing Congestion In Resource Networks, Pradeep Varakantham, Na Fu, William Yeoh, Shih-Fen Cheng, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Congestion occurs when there is competition for resources by sel sh agents. In this paper, we are concerned with smoothing out congestion in a network of resources by using personalized well-timed in- centives that are subject to budget constraints. To that end, we provide: (i) a mathematical formulation that computes equilibrium for the re- source sharing congestion game with incentives and budget constraints; (ii) an integrated approach that scales to larger problems by exploiting the factored network structure and approximating the attained equilib- rium; (iii) an iterative best response algorithm for solving the uncon- strained version (no budget) of the …


Communicating Intended Routes In Ecdis: Evaluating Technological Change, Thomas Porathe, Margareta Lützhöft, Gesa Praetorius Oct 2013

Communicating Intended Routes In Ecdis: Evaluating Technological Change, Thomas Porathe, Margareta Lützhöft, Gesa Praetorius

Gesa Praetorius

Misunderstanding each other's intentions is one of the most common causes of shipping accidents. By sending out a number of waypoints ahead and displaying them on the Electronic Chart Display and Information System (ECDIS) a ship's intentions would be clearly visible for other ships. Displaying ships’ intentions would be a major change compared to navigation today. It could be very beneficial but it could also have unintended consequences. This paper reports on findings from an evaluation looking for unintended consequences of change using system simulation. During the simulation an unanticipated behavior was observed. Bridge crews started to click and drag …


Interaction Model Of Functions In The National Airspace System, Nathan F. Koerschner, Steven J. Landry Oct 2013

Interaction Model Of Functions In The National Airspace System, Nathan F. Koerschner, Steven J. Landry

The Summer Undergraduate Research Fellowship (SURF) Symposium

The National Airspace System (NAS) is comprehensively described by five functions derived from big-picture goals: (1) conflict detection and resolution, (2) controlling aircraft states, (3) traffic flow management, (4) controlling passenger states, and (5) controlling company resources. It can be reasonably assumed that these functions interact in some way; this interaction is currently unknown. A model of the entire NAS would be helpful in discovering these interactions, yet no such comprehensive model exists. To address this problem an agent-based state-based model was created in MATLAB. To date, only functions (1) and (2) were implemented. Running the model shows that there …


Quantitative Measurement Of Intuitiveness Of Visualization Techniques, Jeongjoon Boo, Ji Soo Yi Oct 2013

Quantitative Measurement Of Intuitiveness Of Visualization Techniques, Jeongjoon Boo, Ji Soo Yi

The Summer Undergraduate Research Fellowship (SURF) Symposium

More and more visualizations and infographics are being adopted as a part of data communication (e.g., news articles and personal blogs) because they can not only present more details succinctly but also allow viewers explore data by themselves. However, when an information provider needs to decide which type of graphs, there is not much reliable information out there. For example, we do not know what portion of general public understands how to comprehend a type of graph, such as a scatter plot, without any explanation. Thus, the aim of this project is to quantify the level of intuitiveness of different …


Pulsed Laser Coating Of Bioceramic (Hap) And Niti Nanoparticles On Metallic Implants, Aayush Goswami, Gary J. Cheng Oct 2013

Pulsed Laser Coating Of Bioceramic (Hap) And Niti Nanoparticles On Metallic Implants, Aayush Goswami, Gary J. Cheng

The Summer Undergraduate Research Fellowship (SURF) Symposium

This research deals with increasing the biocompatibility of the bio implants which have a global market valued more than $94.1 billion . The surface of the metal alloys used for the bone implants need to be coated with bio compatible materials like HAp(Hydroxyapatite), graphene, etc. in order to promote the growth of cells(osteoblasts) on the surface of the implants. Various techniques like plasma spray coating, ion beam sputter coating, etc. have been used before to coat such materials on a substrate, however these have faced problems of coating quality. In order to perfect this coating, that is make it more …


Parcel-Level Redevelopment Strategies For Distressed Neighborhoods, Michael P. Johnson Jr., Justin Hollander Oct 2013

Parcel-Level Redevelopment Strategies For Distressed Neighborhoods, Michael P. Johnson Jr., Justin Hollander

Michael P. Johnson

Certain distressed neighborhoods cannot support traditional residential-focused development. For these communities, we develop decision models for acquisition and redevelopment of chronically vacant lands and structures for primarily non-residential and greening uses. We address social benefits and costs of redevelopment strategies, parcel clustering to exploit economies of scale, and conflicting values among stakeholders. We illustrate our models using data from Baltimore, MD.


The Effect Of Distribution On Product Temperature Profile In Thermally Insulated Containers For Express Shipments, Jay Singh, Sanjiv Jaggia, Koushik Saha Oct 2013

The Effect Of Distribution On Product Temperature Profile In Thermally Insulated Containers For Express Shipments, Jay Singh, Sanjiv Jaggia, Koushik Saha

Industrial Technology and Packaging

An uninterrupted cold chain is a continual series of storage and distribution activities that maintain a specific temperature or temperature range. Cold chain solutions typically involve excessive packaging to ensure that the desired product temperature is maintained through the distribution process, thereby increasing the logistics-related costs. There is a myriad of solutions available for shipping temperature-sensitive products, including those constructed with a variety of packaging materials as well as refrigerants. Although static characteristics for thermally insulated packaging solutions such as the R-values of package systems as well as the melting points and heat absorption rates of various refrigerants have been …


Acuta Enews October 2013 Vol. 42, No. 10 Oct 2013

Acuta Enews October 2013 Vol. 42, No. 10

ACUTA Newsletters

In this Issue...

1 Nominate for Board of Directors

1 PD and More from ACUTA

2 Nominations Open for institutional Excellence Award

3 What's on Your Desk?

4 Using Social Media During Times of Crisis

5 Why You Should Customize Lync' qualified Phones

6 Board Report

7 Info Links

8 Welcome New Members

8 Check It Out


Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo Oct 2013

Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo

Mingyi Hong

In a wireless system with a large number of distributed nodes, the quality of communication can be greatly improved by pooling the nodes to perform joint transmission/reception. In this paper, we consider the problem of optimally selecting a subset of nodes from potentially a large number of candidates to form a virtual multi-antenna system, while at the same time designing their joint linear transmission strategies. We focus on two specific application scenarios: 1) multiple single antenna transmitters cooperatively transmit to a receiver; 2) a single transmitter transmits to a receiver with the help of a number of cooperative relays. We …


Algorithmic And Mathematical Programming Approaches To Scheduling Problems With Energy-Based Objectives, Kan Fang Oct 2013

Algorithmic And Mathematical Programming Approaches To Scheduling Problems With Energy-Based Objectives, Kan Fang

Open Access Dissertations

This dissertation studies scheduling as a means to address the increasing concerns related to energy consumption and electricity cost in manufacturing enterprises. Two classes of problems are considered in this dissertation: (i) minimizing the makespan in a permutation flow shop with peak power consumption constraints (the PFSPP problem for short) and (ii) minimizing the total electricity cost on a single machine under time-of-use tariffs (the SMSEC problem for short). We incorporate the technology of dynamic speed scaling and the variable pricing of electricity into these scheduling problems to improve energy efficiency in manufacturing.The challenge in the PFSPP problem is to …


Human Cognitive Performance In Healthcare Information System Environment And Its Application On Nursing Tasks, Byung Cheol Lee Oct 2013

Human Cognitive Performance In Healthcare Information System Environment And Its Application On Nursing Tasks, Byung Cheol Lee

Open Access Dissertations

The US healthcare system has serious issues in care quality and patient safety. Patients often do not receive the care they need or the given care service cause harm. In addition, the significant amounts of medical and medication errors occur, and recurring adverse drug events due to damaging side effects from medications threaten patient safety. To solve these issues, healthcare information systems (HIS) have been recommended in various care processes. Though several studies have confirmed the benefits and usefulness of the systems (Cordero, Kuehn, Kumar, & Mekhjian, 2004; Kohn, Corrigan, & Donaldson, 2000; Sittig, Krall, Kaalaas-Sittig, & Ash, 2005; Weiner …


Design, Development, And Testing Of A Conformal Power Control Interface For Thrust Vectoring Aircraft, David Rozovski Oct 2013

Design, Development, And Testing Of A Conformal Power Control Interface For Thrust Vectoring Aircraft, David Rozovski

Open Access Dissertations

Over the last five years, a new power control inceptor for tiltrotor aircraft, known as the Rotational Throttle Interface (RTI) was designed and built. Prior to the RTI, no tiltrotor inceptor had been able to simultaneously indicate both the direction and magnitude of thrust conformally. The purpose of the RTI is to provide an interface that maps to the intended vehicle response throughout ALL ranges of operation. Doing so is expected to reduce confusion that may have contributed to several tiltrotor accidents

Two tests were conducted with the RTI, one at the NASA Vertical Motion Simulator, and one at Canada's …


Modeling The Impact Of Simulated Educational Interventions On The Use And Abuse Of Pharmaceutical Opioids In The United States: A Report On Initial Efforts, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt, Dennis Mccarty, Lynn Webster, John Fitzgerald, J. David Haddox Oct 2013

Modeling The Impact Of Simulated Educational Interventions On The Use And Abuse Of Pharmaceutical Opioids In The United States: A Report On Initial Efforts, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt, Dennis Mccarty, Lynn Webster, John Fitzgerald, J. David Haddox

Systems Science Faculty Publications and Presentations

Three educational interventions were simulated in a system dynamics model of the medical use, trafficking, and nonmedical use of pharmaceutical opioids. The study relied on secondary data obtained in the literature for the period of 1995 to 2008 as well as expert panel recommendations regarding model parameters and structure. The behavior of the resulting systems-level model was tested for fit against reference behavior data. After the base model was tested, logic to represent three educational interventions was added and the impact of each intervention on simulated overdose deaths was evaluated over a 7-year evaluation period, 2008 to 2015. Principal findings …


An Ergonomic Evaluation Of Aircraft Pilot Seats, Yolanda Nicole Andrade Oct 2013

An Ergonomic Evaluation Of Aircraft Pilot Seats, Yolanda Nicole Andrade

Doctoral Dissertations and Master's Theses

Seat comfort has become increasingly important in today's society as we spend more time at consoles, instrument panels, or just online. However, seat comfort is hard to define and difficult to measure. Several measures both objective and subjective were used to evaluate seat comfort in commercially available average pilot seats. Three pilot seats, which had the same material and similar adjustments but different physical attributes, and a universal classroom seat, with different material and no adjustments, were compared by 20 volunteers using subjective and objective measures in a Latin square controlled repeated measures design. A Friedman's test was used to …


Enhanced Adaptive Management: Integrating Decision Analysis, Scenario Analysis And Environmental Modeling For The Everglades, Matteo Convertino, Christy Foran, Jeffrey Keisler, Lynn Scarlett, Andrew Loschiavo, Greg Kiker, Igor Linkov Sep 2013

Enhanced Adaptive Management: Integrating Decision Analysis, Scenario Analysis And Environmental Modeling For The Everglades, Matteo Convertino, Christy Foran, Jeffrey Keisler, Lynn Scarlett, Andrew Loschiavo, Greg Kiker, Igor Linkov

Jeffrey Keisler

We propose to enhance existing adaptive management efforts with a decision-analytical approach that can
guide the initial selection of robust restoration alternative plans and inform the need to adjust these
alternatives in the course of action based on continuously acquired monitoring information and changing
stakeholder values. We demonstrate an application of enhanced adaptive management for a wetland
restoration case study inspired by the Florida Everglades restoration effort. We find that alternatives
designed to reconstruct the pre-drainage flow may have a positive ecological impact, but may also have high
operational costs and only marginally contribute to meeting other objectives such as …


Acuta Enews September 2013 Vol. 42, No. 9 Sep 2013

Acuta Enews September 2013 Vol. 42, No. 9

ACUTA Newsletters

In this Issue...

1 Big Data Means Big Advances

2 Nominations Open for 2014 institutional Excellence Award

2 Seeking Presenters for Winter Seminar

3 Webinar: The Evolution of Control Systems Security Brief

3 Register to Attend Fall Seminar

4 What Exactly Is a Microsoft Lync Phone?

6 Info Links

7 Overheard on the Listserv

8 Board Report

9 Welcome New Members

9 Check It Out


On The Allocation Of Exclusive-Use Counters For Airport Check-In Queues: Static Vs. Dynamic Policies, Mahmut Parlar, Brian Rodrigues, Sharafali Moosa Sep 2013

On The Allocation Of Exclusive-Use Counters For Airport Check-In Queues: Static Vs. Dynamic Policies, Mahmut Parlar, Brian Rodrigues, Sharafali Moosa

Research Collection Lee Kong Chian School Of Business

In this paper we propose a static policy for the optimal allocation of a fixed number of exclusive-use check-in counters dedicated to a single flight. We first provide the motivation for considering the static policy by showing that the dynamic policy already available in the literature suffers from the curse of dimensionality. The objective is to minimize the (expected) total cost of waiting, counter operation, and passenger delay costs which we show to be convex in the number of counters allocated. In those cases where the passenger delay cost is difficult to estimate, we propose an alternative formulation and minimize …


Study Of A Molten Carbonate Fuel Cell Combined Heat, Hydrogen And Power System: End-Use Application, Tarek A. Hamad, Abdulhakim Amer A. Agll, Yousif M. Hamad, Sushrut Bapat, Mathew Thomas, Kevin B. Martin, John W. Sheffield Sep 2013

Study Of A Molten Carbonate Fuel Cell Combined Heat, Hydrogen And Power System: End-Use Application, Tarek A. Hamad, Abdulhakim Amer A. Agll, Yousif M. Hamad, Sushrut Bapat, Mathew Thomas, Kevin B. Martin, John W. Sheffield

Engineering Management and Systems Engineering Faculty Research & Creative Works

To address the problem of fossil fuel usage and high greenhouse gas emissions at the Missouri University of Science and Technology campus, using of alternative fuels and renewable energy sources can lower energy consumption and greenhouse gas emissions. Biogas, produced by anaerobic digestion of wastewater, organic waste, agricultural waste, industrial waste, and animal by-products is a potential source of renewable energy. In this work, we have discussed the design of CHHP system for the campus using local resources. An energy flow and resource availability study is performed to identify the type and source of feedstock required to continuously run the …


Development Of Availability And Sustainability Spares Optimization Models For Aircraft Reparables, Edmund K.W. Pek Sep 2013

Development Of Availability And Sustainability Spares Optimization Models For Aircraft Reparables, Edmund K.W. Pek

Theses and Dissertations

The Republic of Singapore Air Force (RSAF) conducts Logistics Support Analysis (LSA) studies in various engineering and logistics efforts on the myriad of weapon systems. In these studies, inventory spares provisioning, availability and sustainability analyses are key focus areas to ensure asset sustenance. In particular, OPUS10, a commercial-off-the-shelf software, is extensively used to conduct reparable spares optimization in acquisition programs. However, it is limited in its ability to conduct availability and sustainability analyses of time-varying operational demands, crucial in Operations & Support (O&S) and contingency planning. As the RSAF seeks force structure expansion to include more sophisticated weapon systems, the …


A Study On Correlation Between Consciousness Level And Performance Of The Worker, Devendra Kumar Chaturvedi Dr., Manish Kumar Arya Aug 2013

A Study On Correlation Between Consciousness Level And Performance Of The Worker, Devendra Kumar Chaturvedi Dr., Manish Kumar Arya

Manish Kumar Arya

Consciousness is significantly related to workplace performance among managers and workers. A considerable amount of research indicates that consciousness is one of the best predictors of performance in the workplace. Conscious employees are generally more reliable, more motivated, and harder working. They have also lower rate of absenteeism and counterproductive work behaviours such as stealing and fighting with other employees. Furthermore, consciousness is the only personality trait that correlates with performance across all categories of jobs. This is a pilot study to determine the workers performance related with consciousness. The consciousness will be experimentally measured using the self developed sensor …


Acuta Enews August 2013 Vo. 42, No. 8 Aug 2013

Acuta Enews August 2013 Vo. 42, No. 8

ACUTA Newsletters

In this Issue.,,

1 Sewanee Campus Celebrates IEA Award

2 Regulatory Webinar on Section 255

2 ACUTA Webinar: What's on the Radar?

2 Sneak Peek at 2014 ACUTA journal Topics i

Vendor System lntegrations Accelerate in the Safety 6 Security Industry j

Seeking Presenters for Winter Seminar

4 Deja vu All Over Again: Can We Please Put SDNs in Context?

5 Some Thoughts about Fiber Optics

6 lnfo Links

6 Mark Your Calendar for Fall Seminar

7 Looking for a Few Good Coordinators

7 Board Report

8 Welcome New Members

8 Check It Out


Innovation And Learning Through Knowledge Gatekeepers:A Critical Examination Of The Relationship Betweentrust, Openness, And The Use Of Gatekeepers, Deogratias Harorimana Dr Aug 2013

Innovation And Learning Through Knowledge Gatekeepers:A Critical Examination Of The Relationship Betweentrust, Openness, And The Use Of Gatekeepers, Deogratias Harorimana Dr

Dr Deogratias Harorimana

The term ‘gatekeeper’ is widely used to represent a class of those who collect information, knowledge and contextualise this before they can share with the rest of the members of the organisation knowledge networks-both formal and informal organisations. In this study, it was found:

1 that there is a strong relationship between the openness of a given firm, as regards its knowledge sharing culture and level trust, and that firm’s use of knowledge gatekeepers

2 that the stage of a given firm’s growth corresponds to its strategic use of different types of gatekeeping.

In early and decline (renewal) stages, for …


The Role Of Third Party Logistics Providers (3pls) In The Adoption Of Green Supply Chain Initiatives, Edward Sweeney, Pietro Evangelista, Maria Huge-Brodin, Karin Isaksson Aug 2013

The Role Of Third Party Logistics Providers (3pls) In The Adoption Of Green Supply Chain Initiatives, Edward Sweeney, Pietro Evangelista, Maria Huge-Brodin, Karin Isaksson

Practitioner Journals

The increasing importance of environmental sustainability has sharpened the focus on the need for innovative approaches to the purchasing of transport and logistics services. This article points out some of the challenges that purchasers of transport and logistics services, as well as their suppliers in the third party logistics (3PL) industry, are facing. These include the need for closer collaboration between 3PLs and their customers, as well as developing systems for the robust assessment of the environmental sustainability of services. The article is based on several years’ research experience inIreland,ItalyandSweden.


Using Real-Time Location Systems & Simulation Modeling To Improve Healthcare, Colby Thomas Mattie Aug 2013

Using Real-Time Location Systems & Simulation Modeling To Improve Healthcare, Colby Thomas Mattie

Masters Theses

In the healthcare industry, facility managers often find themselves with limited resources, lack of timely data, and unexpected crises that they have to respond too. Their options are based on hastily made assumptions and a limited understanding of all implications of the problems at hand. This scenario has become a concerning issue for the healthcare industry where problems can arise at any time and every minute counts. The healthcare industry is also littered with wasteful processes and regulations that increase the cost for physicians and facility operators and decrease the overall care for the patients. This is very evident in …


A Multi-Echelon Inventory System With Supplier Selection And Order Allocation Under Stochastic Demand, Cong Guo Aug 2013

A Multi-Echelon Inventory System With Supplier Selection And Order Allocation Under Stochastic Demand, Cong Guo

Masters Theses

This article addresses the development of an integrated supplier selection and inventory control problems in supply chain management by developing a mathematical model for a multi-echelon system. In particular, a buyer firm that consists of one warehouse and N identical retailers wants to procure a type of product from a group of potential suppliers, which may require different price, ordering cost, lead time and have restriction on minimum and maximum total order size, to satisfy the stochastic demand. A continuous review system that implements the order quantity, reorder point (Q, R) inventory policy is considered in the …


Parameterizing Analytical Models To Support An Empirically Based Warehouse Design Methodology, Lisa Thomas Aug 2013

Parameterizing Analytical Models To Support An Empirically Based Warehouse Design Methodology, Lisa Thomas

Graduate Theses and Dissertations

Research in the area of warehouse design is characterized by a myriad of analytical models that address one, typically small and isolated, area of the warehouse. These models, although important in gaining insight into one question of warehouse design, are of limited value when one considers the larger question of overall warehouse design. Thus, research in the area of overall warehouse design typically consists of procedure-driven processes based on qualitative factors and not the quantifiable results of analytical models.

In contrast, practitioners have significant empirical data related to how a design alternative performs in an industry, a company, or a …