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2010

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Articles 181 - 210 of 336

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

Height Adjustment In Assessing Dual Energy X-Ray Absorptiometry Measurements Of Bone Mass And Density In Children, Babette S. Zemel, Mary B. Leonard, Andrea Kelly, Joan M. Lappe, Vicente Gilsanz, Sharon Oberfield, Soroosh Mahboubi, John A. Shepherd, Thomas N. Hangartner, Margaret M. Frederick, Karen K. Winer, Heidi J. Kalkwarf Mar 2010

Height Adjustment In Assessing Dual Energy X-Ray Absorptiometry Measurements Of Bone Mass And Density In Children, Babette S. Zemel, Mary B. Leonard, Andrea Kelly, Joan M. Lappe, Vicente Gilsanz, Sharon Oberfield, Soroosh Mahboubi, John A. Shepherd, Thomas N. Hangartner, Margaret M. Frederick, Karen K. Winer, Heidi J. Kalkwarf

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Context: In children, bone mineral content (BMC) and bone mineral density (BMD) measurements by dual-energy x-ray absorptiometry (DXA) are affected by height status. No consensus exists on how to adjust BMC or BMD (BMC/BMD) measurements for short or tall stature.

Objective: The aim of this study was to compare various methods to adjust BMC/BMD for height in healthy children.

Design: Data from the Bone Mineral Density in Childhood Study (BMDCS) were used to develop adjustment methods that were validated using an independent cross-sectional sample of healthy children from the Reference Data Project (RDP).

Setting: We conducted the study in five …


Axle Assembly Takt Time Change, Punit Shivji Mar 2010

Axle Assembly Takt Time Change, Punit Shivji

Industrial and Manufacturing Engineering

The Toyota managed New United Motor Manufacturing Inc. automotive plant is currently going through difficult economic times. To prepare for future production demands, the plant will need to decrease production output and maintain a lower volume of vehicles produced with a high level of quality and efficiency. This project will take on the reorganization of the rear axle assembly lines and the departments that are involved to ensure a cost effective, efficient, and safe approach in manufacturing Toyota's Tacomas. Toyota recommends the Toyota production system as well as any knowledge and experience obtained from previous jobs and coursework to be …


Analysis Of An Economic Order Quantity And Reorder Point Inventory Control Model For Company Xyz, Jose L. Gonzalez, Daniel Gonzalez Mar 2010

Analysis Of An Economic Order Quantity And Reorder Point Inventory Control Model For Company Xyz, Jose L. Gonzalez, Daniel Gonzalez

Industrial and Manufacturing Engineering

As a result to today’s uncertain economy, companies are searching for alternative ways to stay competitive. In which, Company XYZ has been faced with an ineffective forecasting method that has lead to multiple product stock outs. The issue faced has caused sales loss as well as profit loss, which companies can not afford to lose if they want to stay competitive. This project goes through the process of analyzing the company’s current forecasting model and recommending an inventory control model to help them solve their current issue. As a result, an Economic Order Quantity (EOQ) and a Reorder Point was …


Nato Human View Architecture And Human Networks, Holly A. H. Handley, Nancy P. Houston Mar 2010

Nato Human View Architecture And Human Networks, Holly A. H. Handley, Nancy P. Houston

Engineering Management & Systems Engineering Faculty Publications

The NATO Human View is a system architectural viewpoint that focuses on the human as part of a system. Its purpose is to capture the human requirements and to inform on how the human impacts the system design. The viewpoint contains seven static models that include different aspects of the human element, such as roles, tasks, constraints, training and metrics. It also includes a Human Dynamics component to perform simulations of the human system under design. One of the static models, termed Human Networks, focuses on the human-to-human communication patterns that occur as a result of ad hoc or deliberate …


Measurement And Analysis Of Truck And Rail Vibration Levels In Thailand, V. Chonhenchob, Paul Singh, Jay A. Singh, S. Sittipod, D. Swasdee, Supoj Pratheepthinthong Mar 2010

Measurement And Analysis Of Truck And Rail Vibration Levels In Thailand, V. Chonhenchob, Paul Singh, Jay A. Singh, S. Sittipod, D. Swasdee, Supoj Pratheepthinthong

Industrial Technology and Packaging

Worldwide increase in trade, foreign direct investment, capital flows, migration and the spread of technology has caused an increased focus to be put on designing packages that can protect goods shipped globally. This requires a wide-ranging understanding of the distribution environments on a global basis. Several past studies have mapped the vibration levels for surface transportation along the most popular shipment routes in countries such as Brazil, Canada, China, India and the USA. This study was conducted to provide a comprehensive understanding of the vibration levels observed for truck and rail shipments for major transportation routes in Thailand, one of …


Facility And Database Design For The Research Development Center, Nicholas J. Mehas Mar 2010

Facility And Database Design For The Research Development Center, Nicholas J. Mehas

Industrial and Manufacturing Engineering

The purpose of this project is to create a new facility and database design to replace the current Research Development Center located on the campus of California Polytechnic State University San Luis Obispo and the database in use at the facility. Currently the Research Development Center is a condemned building and the database lacks up-to-date technology. The project will develop new designs for both, based on concurrent engineering. The outcome of the project will be a new design for a new building that increases capacity and capability; a new database design that integrates newer technologies and methods for tracking tools.


E-Waste Solutions For Cal Poly And The Central Coast, Andrea Schmidt Mar 2010

E-Waste Solutions For Cal Poly And The Central Coast, Andrea Schmidt

Industrial and Manufacturing Engineering

Executive Summary The focus of this paper is to explore the feasibility of an e-waste processing lab on the Cal Poly campus which can operate as an ongoing service to the community while maintaining an academic focus on the issues of end-of-life electronics. The result is a 30’ by 60’ lab on campus that includes 40 work stations, and 3,848 square feet of shelving. The lab can be entirely run by students with 36 hours per week of inspection and pre-production inventory activities and 6 hours of de-manufacturing activities, processing 264 e-waste units per month. Cal Poly students will train …


Acuta Enews February 2010, Vol 39, No. 2 Feb 2010

Acuta Enews February 2010, Vol 39, No. 2

ACUTA Newsletters

In This Issue

From the President.......... Harvey "Buck" Buchanan, Florida State Univ. ACUTA President

Tech Talk: MANET: Not the Art, but the Science......... Kevin Tanzill, Dux PR

Cast Your Vote for ACUTA Board

DC Update........... Dave Ostrom, Washington State Univ. (retired)

Overheard on the Listserv: Handling Large Volumes of Incoming Calls

Washington Update Newsletter

Your State/Province Could Be #1

A Rank Amateur's Guide to Twitter........... Daphne Gray-Grant

Thanks to Sponsors for 2009

Multi-Event Discount: Attend More in 2010 and Save More!

Bring Winter Seminar to Your Desktop

Board Report............ George Denbow, Univ. of Texas, ACUTA Secretary/ Treasurer

Info Links........... Randy …


Peer Review Of Teaching Project - Castl: Expanding The Sotl Commons Cluster Final Report, Jennifer Meta Robinson, Paul Savory, Gary Poole, Tom Carey, Dan Bernstein Feb 2010

Peer Review Of Teaching Project - Castl: Expanding The Sotl Commons Cluster Final Report, Jennifer Meta Robinson, Paul Savory, Gary Poole, Tom Carey, Dan Bernstein

Department of Industrial and Management Systems Engineering: Reports

In 2006, the Peer Review of Teaching Project at the University of Nebraska-Lincoln was selected to join the Carnegie Academy for the Scholarship of Teaching and Learning (CASTL) Institutional Leadership Program. Our participation in this national leadership program (“Expanding the Teaching Commons: A social and technical infrastructure to promote and support effective learning & student success, through teacher community collaborations to develop, adapt, share and mobilize pedagogical content knowledge, exemplary practices, and shared resources.”) allowed us to engage a broad audience to help define, develop, refine, and share the models and approaches of our project. The combined group effort for …


Further Exploration On Relationship Between Crisp Sets And Fuzzy Sets, Zhaoxia Wang, Quan Wang, Ming Bai, Chen Zeng-Qiang, Zhen Sun Feb 2010

Further Exploration On Relationship Between Crisp Sets And Fuzzy Sets, Zhaoxia Wang, Quan Wang, Ming Bai, Chen Zeng-Qiang, Zhen Sun

Research Collection School Of Computing and Information Systems

This paper employs the concept of fuzzify upgrade operator to describe the relationship between crisp sets, fuzzy sets and higher order fuzzy sets, such as type-2 fuzzy sets. Theory analysis and case studies demonstrate that a crisp set can be represented by a type-1 fuzzy set, a type-1 fuzzy set can be represented by a type-2 fuzzy set, and a type-n (n>=2) fuzzy set can be represented by a type-(n+1) (n>=2) fuzzy set. The fuzzify upgrade operator makes crisp sets, type-1 fuzzy sets, type-2 fuzzy sets and any fuzzy sets much more accessible to all readers. The relationship …


An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh Feb 2010

An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh

Research Collection School Of Computing and Information Systems

We construct an agent-based model to study the interplay between extreme price shocks and illiquidity in the presence of systematic traders known as trend followers. The agent-based approach is particularly attractive in modeling commodity markets because the approach allows for the explicit modeling of production, capacities, and storage constraints. Our study begins by using the price stream from a market simulation involving human participants and studies the behavior of various trend-following strategies, assuming initially that their participation will not impact the market. We notice an incremental deterioration in strategy performance as and when strategies deviate further and further from the …


Resource Assignment In Short Life Technology Intensive (Slti) New Product Development (Npd), Randy A. Reagan Jan 2010

Resource Assignment In Short Life Technology Intensive (Slti) New Product Development (Npd), Randy A. Reagan

Dissertations

Enterprises managing multiple concurrent New Product Development (NPD) projects face significant challenges assigning staff to projects in order to achieve launch schedules that maximize financial returns. The challenge is increased with the class of Short Life Technology Intensive (SLTI) products characterized by technical complexity, short development cycles and short revenue life cycles. Technical complexity drives the need to assign staffing resources of various technical disciplines and skill levels. SLTI products are rapidly developed and launched into stationary market windows where the revenue life cycle is short and decreasing with any time-to-market delay. The SLTI-NPD project management decision is to assign …


End-Of-Life Analysis Of Nanotechnology Products, Sun Olapiriyakul Jan 2010

End-Of-Life Analysis Of Nanotechnology Products, Sun Olapiriyakul

Dissertations

Previous research has shown that thermodynamic properties including melting point and specific heat capacity of nanomaterials may be higher than that of their corresponding bulk materials. The melting point elevation and specific heat capacity enhancement of nanomaterials may result in increased energy consumption and waste gases emission at the end-of-life (EOL) stage where the products containing nanomaterials are recycled by high temperature metal recovery (HTMR) process.

In this dissertation, the effect of physical characteristics of nanomaterials, referred to as physicochemical parameters, on their melting temperature and specific heat capacity was investigated. In addition, physical, chemical, and thermodynamic properties of nanomaterials …


Acuta Enews January 2010, Vol 39, No. 1 Jan 2010

Acuta Enews January 2010, Vol 39, No. 1

ACUTA Newsletters

In this Issue

From ACUTA Headquarters: Seizing Opportunity in a New Decade.... Jeri A. Semer, CAE, Executive Dir.

Where Were You in 2000? Where Will You Be in 2020?

Tech Talk: When Reality Isn't Good Enough, Augment It.......... Kevin, Tanzillo, Dux PR

Multi-Event Discount: Attend More in 2010 and Save More!

DC Update............. Dave Ostron, Washington State Univ. (retired)

Come to New Orleans- Or Bring New Orleans to Your Office

Nominate Now for ACUTA Ruth A Mickalecki Leadership Award

Be a Moderator or Monitor at the Annual Conference

Board Report.......... Jeri A. Semer, CAE, Executive Director

Info Links............. Randy Hayes, …


A Review Of Programmable Logic Controllers In Control Systems Education, Michael R. Foster, Chad Hammerquist, Robert Melendy Jan 2010

A Review Of Programmable Logic Controllers In Control Systems Education, Michael R. Foster, Chad Hammerquist, Robert Melendy

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

A Programmable Logic Controller (PLC) is a standard industrial control device that provides a simple, yet robust, method of controlling manufacturing and dynamic processes. As a result of their low cost, adaptability, and reliability, PLCs are by far the most common control mechanism used by manufacturing businesses of all sizes for environment control, food processing, motion control, and automated test equipment. Yet even though PLCs are heavily used by industry, their use in teaching control theory concepts is uncommon for mechanical engineering programs. Traditional control systems engineering courses focus on the theory and mathematics of continuous-based control systems and rarely …


Process Design For Aeration Of Facial Prosthetic, Nathaniel J. Urciuoli Jan 2010

Process Design For Aeration Of Facial Prosthetic, Nathaniel J. Urciuoli

Industrial and Manufacturing Engineering

Facial prosthetics are becoming a necessary step for the recovery of injured veterans and civilians who have suffered severe facial burning. Current users of such prosthetics are not able to wear the prosthetic for an extended period of time due to uncomfortable conditions created by the silicone material. A solution for this problem was to develop a process for creating small holes similar to skin pores that will both ventilate and aid in the evaporation of accumulated sweat under the prosthetic.

The main steps of this process were to create a flexible fixture capable of supporting and securing the prosthetic …


Decision Analysis Tool For Appropriate Water Treatment Technologies In Improverished Villages, Conner David Johnston Jan 2010

Decision Analysis Tool For Appropriate Water Treatment Technologies In Improverished Villages, Conner David Johnston

Industrial and Manufacturing Engineering

No abstract provided.


Funeral Services Marketing Interface To Enhance Customer Service And Overall Productivity, Alyssa R. Habing Jan 2010

Funeral Services Marketing Interface To Enhance Customer Service And Overall Productivity, Alyssa R. Habing

Industrial and Manufacturing Engineering

Customer satisfaction is the ultimate goal of any business regardless of the industry it resides in; it’s the sole driver of a company’s productivity levels and overall success within the market. Although numb to most market fluctuations, the funeral industry needs to reinvent their business strategies continuously in order to increase their market share. It’s especially important for smaller funeral homes across the world to take this idea to another level in order to stay competitive with the larger, corporate establishments. In the past twenty years, the industry has grown exponentially due to more interest and popularity. The increase in …


Energy Audit And Optimization For "Arches Etc.", James Ross Dixon Jan 2010

Energy Audit And Optimization For "Arches Etc.", James Ross Dixon

Industrial and Manufacturing Engineering

Arches etc. is a San Diego business, which specializes in the manufacture, distribution, and installation of custom designed doors, windows, mouldings, and hardware. Due to the recent economic downturn, which has hindered the construction industry, Arches etc. believed that an analysis and optimization of their energy usage would provide additional assistance towards their goal to lower overhead and maintain current operations.

To begin this task, a comprehensive energy audit was conducted to establish an initial state from which to base improvements. Arches etc.’s current monthly utility bill averages $996, which solidifies the accuracy of this project’s performed energy audit, estimating …


Recycling Made Easy: An Ergonomic Approach To Home Recycling And Trash Containers, Landon P. Boisclair Jan 2010

Recycling Made Easy: An Ergonomic Approach To Home Recycling And Trash Containers, Landon P. Boisclair

Industrial and Manufacturing Engineering

The purpose of this project is to create an ergonomically sound recycling/trash container, with the ultimate hope of making the recycling process easier and more intuitive, thereby increasing recycling rates. Currently, while there are many recycling/trash containers available for purchase, there is no product that has a design without glaring ergonomic flaws. An ergonomic design and product prototype was created as a part of this project, and was subsequently tested against a conventional prototype model. The data collected from the experiments conducted suggests that the new ergonomic model makes the waste disposal process and the container transportation process easier, while …


Nonprofit Management Through Effective Database Utilization, Jennifer Muscat Jan 2010

Nonprofit Management Through Effective Database Utilization, Jennifer Muscat

Industrial and Manufacturing Engineering

This project addresses problems found within a specific department within Lifewater International. Lifewater faces many unique challenges operating as a nonprofit. Like most nonprofits, elaborate costly solutions are simply not an option when solving department problems. This project addresses three interrelated problems within Lifewater’s Development and Communications Department. The three issues addressed are Volunteer Management, Donor Management, and Project Management. Each problem was examined to determine the areas for improvement that this project can handle and solve. Each problem was given an improved design. A Volunteer Management System was designed to increase volunteer utilization and appropriately match volunteers with appropriate …


Air-Exposed Microbial Fuel Cells And Screening Techniques, Justin C. Biffinger, Bradley R. Ringeisen Jan 2010

Air-Exposed Microbial Fuel Cells And Screening Techniques, Justin C. Biffinger, Bradley R. Ringeisen

United States Navy: Publications

Microbial fuel cells (MFCs) harvest energy from a wide variety of natural carbon sources to produce electricity at neutral pH and ambient temperatures. To date, standard H2/O2 PEMFC technology has yet to generate significant power under those conditions. Because most environments on earth are exposed to significant levels of oxygen, we believe the transition from sediment based MFCs to oxygen-tolerant MFCs is necessary. This transition would require both a way to simultaneously sequester the metal-reducing microbes and reduce the overall concentration of oxygen in the anode chamber. Recent work suggests that power can be generated with significant …


Probing Electron Transfer Mechanisms In Shewanella Oneidensis Mr-1 Using A Nanoelectrode Platform And Single-Cell Imaging, Ziaocheng Jiang, Jinsong Hu, Lisa A. Fitzgerald, Justin C. Biffinger, Ping Xie, Bradley R. Ringeisen, Charles M. Lieber Jan 2010

Probing Electron Transfer Mechanisms In Shewanella Oneidensis Mr-1 Using A Nanoelectrode Platform And Single-Cell Imaging, Ziaocheng Jiang, Jinsong Hu, Lisa A. Fitzgerald, Justin C. Biffinger, Ping Xie, Bradley R. Ringeisen, Charles M. Lieber

United States Navy: Publications

Microbial fuel cells (MFCs) represent a promising approach for sustainable energy production as they generate electricity directly from metabolism of organic substrates without the need for catalysts. However, the mechanisms of electron transfer between microbes and electrodes, which could ultimately limit power extraction, remain controversial. Here we demonstrate optically transparent nanoelectrodes as a platform to investigate extracellular electron transfer in Shewanella oneidensis MR-1, where an array of nanoholes precludes or single window allows for direct microbeelectrode contacts. Following addition of cells, short-circuit current measurements showed similar amplitude and temporal response for both electrode configurations, while in situ optical imaging demonstrates …


Metaheuristics For The Integrated Machine Allocation And Layout Problem, Juan Jaramillo, Alan Mckendall Jan 2010

Metaheuristics For The Integrated Machine Allocation And Layout Problem, Juan Jaramillo, Alan Mckendall

Faculty & Staff Scholarship

The Integrated Machine Allocation and Layout Problem (IMALP) is the problem of assigning a set of machines (including machine replicas) to locations while assigning product flows to machines such that Material Handling Cost is minimised. A new mathematical formulation, a Tabu Search (TS) heuristic, and a Memetic Algorithm (MA) are presented for the IMALP. The algorithms were evaluated using a set of test problems available in the literature. TS and the MA obtained equal or better solutions for the dataset than previous techniques presented in the literature. More specifically, TS obtained better solutions in 47% of the instances, and MA …


The Generalised Machine Layout Problem, Juan Jaramillo, Alan Mckendall Jan 2010

The Generalised Machine Layout Problem, Juan Jaramillo, Alan Mckendall

Faculty & Staff Scholarship

The Generalised MAchine Layout Problem (GMALP) is a generalisation of the integrated machine and layout problem, which is an extension of the machine layout problem. More specifically, the GMALP is the designing of a facility layout by defining the product mix, selecting the number of machines to be used, assigning these machines to the plant floor, and assigning products to machines such that total profit is maximised. Moreover, the GMALP integrates the quadratic assignment problem with a multicommodity flow problem. Therefore, the GMALP is a computationally intractable problem. Consequently, a mixed integer nonlinear programming model was developed and used to …


Heuristics For The Dynamic Facility Layout Problem With Unequal-Area Departments, Alan Mckendall, Artak Hakobyan Jan 2010

Heuristics For The Dynamic Facility Layout Problem With Unequal-Area Departments, Alan Mckendall, Artak Hakobyan

Faculty & Staff Scholarship

The dynamic facility layout problem (DFLP) is the problem of finding positions of departments on the plant floor for multiple periods (material flows between departments change during the planning horizon) such that departments do not overlap, and the sum of the material handling and rearrangement costs is minimized. In this paper, the departments may have unequal-areas and free orientations, and the layout for each period is generated on the continuous plant floor. Because of the complexity of the problem, only small-size problems can be solved in reasonable time using exact techniques. As a result, a boundary search (construction) technique, which …


The Role Of Shewanella Oneidensis Mr-1 Outer Surface Structures In Extracellular Electron Transfer, Rachida A. Bouhenni, Gary J. Vora, Justin C. Biffinger, Sheetal Shirodkar, Ken Brockman, Ricky Ray, Peter Wu, Brandy J. Johnson, Eulandria M. Biddle, Matthew J. Marshall, Lisa A. Fitzgerald, Brenda J. Little, Jim K. Fredrickson, Alexander S. Beliaev, Bradley R. Ringeisen, Daad A. Saffarini Jan 2010

The Role Of Shewanella Oneidensis Mr-1 Outer Surface Structures In Extracellular Electron Transfer, Rachida A. Bouhenni, Gary J. Vora, Justin C. Biffinger, Sheetal Shirodkar, Ken Brockman, Ricky Ray, Peter Wu, Brandy J. Johnson, Eulandria M. Biddle, Matthew J. Marshall, Lisa A. Fitzgerald, Brenda J. Little, Jim K. Fredrickson, Alexander S. Beliaev, Bradley R. Ringeisen, Daad A. Saffarini

United States Navy: Publications

The ability of the metal reducer Shewanella oneidensis MR-1 to generate electricity in microbial fuel cells (MFCs) depends on the activity of a predicted type IV prepilin peptidase; PilD. Analysis of an S. oneidensis MR-1 pilD mutant indicated that it was deficient in pili production (Msh and type IV) and type II secretion (T2S). The requirement for T2S in metal reduction has been previously identified, but the role of pili remains largely unexplored. To define the role of type IV or Msh pili in electron transfer, mutants that lack one or both pilus biogenesis systems were generated and analyzed; …


Software Test Automation, Phillip Laplante, Fevzi Belli, Jerry Gao, Greg Kapfhammer, Keith Miller, W. Wong, Dianxiang Xu Jan 2010

Software Test Automation, Phillip Laplante, Fevzi Belli, Jerry Gao, Greg Kapfhammer, Keith Miller, W. Wong, Dianxiang Xu

Education Sciences and Professional Programs Faculty Works

No abstract provided.


Si Implant-Assisted Ohmic Contacts To Gan, Cuong Nguyen, Pankaj Shah, Edward Leong, Michael Derenge, Kenneth Jones Jan 2010

Si Implant-Assisted Ohmic Contacts To Gan, Cuong Nguyen, Pankaj Shah, Edward Leong, Michael Derenge, Kenneth Jones

United States Army: Publications

The contact resistance, ρC, was measured for the traditional Ti/Al/Ni/Au Ohmic contact for samples implanted with Si to >1020 cm-3 and annealed at 1100, 1150, 1200, or 1250°C for 2, 5 or 10 min using an AlN annealing cap. These results are compared with those for samples annealed in the same way, but were not implanted. The as-grown samples were doped to 3.56 × 1017 or 6.67 × 1016 cm-3 or were unintentionally (UI) doped. In almost all cases, ρC for the implanted sample was lower, and a record low ρC …


Characterization Of Nanometer Scale Compositionally Inhomogeneous Algan Active Regions On Bulk Aln Substrates, A. V. Sampath, G. A. Garrett, E. D. Readinger, R. W. Enck, H. Shen, M. Wraback, J. R. Grandusky, L. J. Schowalter Jan 2010

Characterization Of Nanometer Scale Compositionally Inhomogeneous Algan Active Regions On Bulk Aln Substrates, A. V. Sampath, G. A. Garrett, E. D. Readinger, R. W. Enck, H. Shen, M. Wraback, J. R. Grandusky, L. J. Schowalter

United States Army: Publications

The optical and structural properties of AlGaN active regions containing nanoscale compositional inhomogeneities (NCI) grown on low dislocation density bulk AlN substrates are reported. These substrates are found to improve the internal quantum efficiency and structural quality of NCI-AlGaN active regions for high Al content alloys, as well as the interfaces of the NCI with the surrounding wider bandgap matrix, as manifested in the absence of any significant long decay component of the low temperature radiative lifetime, which is well characterized by a single exponential photoluminescence decay with a 330 ps time constant. However, room temperature results indicate that non-radiative …