| High Efficiency, High Power Density Small Hybrid System |
01-Sep-2009 |
97 pages |
| Authors:
Frank M Washko; TYCHEURSIDAEN LLC PACIFICA CA
|
 | The engine system concept disclosed in this proposal meets or exceeds each of the goals stated in Solicitation DARPA 08-010. Our hydraulic hybrid concept will provide extremely high efficiency while reducing weight and increasing power density. The core of this new concept is a standard four-cycle internal combustion engine power cylinder. However, the power cylinder interfaces with a hydraulic system that sends power to a hydraulic hybrid power unit. The ... |
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| Viral Penetration of High Efficiency Particulate Air (HEPA) Filters (PREPRINT) |
Sep-2009 |
39 pages |
| Authors:
Joseph D Wander; Brian K Helmbuch; C Y Wu; APPLIED RESEARCH ASSOCIATES INC TYNDALL AFB FL
|
| High Efficiency Particulate Air (HEPA) filters are the primary technology used for particulate removal in individual and collective protection applications. HEPA filters are commonly thought to be impenetrable, but in fact they are only 99.97% efficient at collecting the most-penetrating particle (approx. 0.3 micrometer). While this is an impressive collection efficiency, HEPA filters may not provide adequate protection for all threats: viruses are submicron in size and have small minimum ... |
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| An Exploratory Study of Alpha Contracting: Antecedents, Processes, Issues, Success Factors and Consequences |
Sep-2009 |
135 pages |
| Authors:
Robert Kirzow; Colleen Sweeney; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Alpha contracting is a collaborative effort between a buyer and supplier during contract formation to maximize efficiency and effectiveness. Although several benefits of Alpha contracting are espoused in the literature, the concept is not ubiquitous, nor is it well understood. The purpose of this Joint Applied Project is to evaluate current Department of Defense (DoD) procedures for the use of Alpha contracting. Specifically, we plan to explore Alpha contracting to ... |
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| Optimal Time and Energy Efficiency in Legged Robotics |
17-Aug-2009 |
5 pages |
| Authors:
Paul Muench; Ka C Cheok; Gregory Czerniak; ARMY RESEARCH DEVELOPMENT AND ENGINEERING COMMAND WARREN MI
|
| Although bio-inspired legged robots have advantageous mobility, they can be very inefficient. Their intrinsic walking mobility is sometimes outweighed by the inefficiency of their drive-train. Some of these inefficiencies are due to collision losses, but they are also due to sub-optimal powering schemes. This paper addresses the powering schemes and seeks to clearly delineate an optimal solution to powering the walking motion of a two-legged or biped walker. We examine ... |
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| The Navy Distributed Engineering Plant (DEP) Bottom Up Review. Building More Efficient Processes and Bridging Communication Gaps |
Apr-2009 |
|
| Authors:
L M Foster; Michael Flory; Ninghao Jiang; William McNavage; CENTER FOR NAVAL ANALYSES ALEXANDRIA VA
|
 | The Distributed Engineering Plant (DEP) within Naval Sea Systems Command (NAVSEA) tasked CNA to conduct a Bottom Up Review (BUR) of the DEP program. The stated goal was to establish more transparency and traceability of clients' requirements through the DEP testing process. In order to address this concern, we examined the process steps, roles and responsibilities, and information-sharing tools involved in DEP combat system interoperability testing. Our analysis shows that ... |
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| Geothermal HVAC Systems - A Business Case Analysis for Net Zero Plus |
Mar-2009 |
55 pages |
| Authors:
Trahan; Ronnie D Jr; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Net Zero Plus (NZ+) is an approved Fiscal Year 2008 Joint Capability Technology Demonstration (JCTD) initiative led by the United States Army Rapid Equipping Force (REF) and the Office of the Secretary of Defense (OSD), Defense Research and Engineering (DDR&E). The purpose of the JCTD initiative is to identify significant military needs and match them to mature technologies or technology demonstration programs, so that military needs can be more rapidly ... |
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| AFRICOM: Does Location Matter? |
Mar-2009 |
95 pages |
| Authors:
Sieber; Otto F III; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| President Bush established United States Africa Command (AFRICOM) in February 2007, which was commissioned fully operational on 1 October 2008. AFRICOM was established to increase DoD's efficiency and effectiveness for African operations and exercises and merged the responsibilities for the African continent into a single command in order to foresee and prevent crises in Africa that could threaten U.S. strategic interests. This merger joined responsibilities previously spread amongst the authorities ... |
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| A Measure of Search Efficiency in a Real World Search Task |
Dec-2008 |
25 pages |
| Authors:
J G Trafton; Melissa R Beck; Maura C Lohrenz; LOUISIANA STATE UNIV BATON ROUGE
|
| In visual search, preattentive processes locate potential target regions and selective attention is directed to potential target locations. The current experiments examined the role of global visual clutter in participants' ability to deploy attention to target regions containing relatively more or less local clutter. Participants searched maps of high, medium, or low global clutter for a target in a high or low local clutter region. Global and local clutter influenced ... |
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| Do the Metrics Make the Mission? |
01-Sep-2008 |
95 pages |
| Authors:
Anthony W Like; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Since Saddam Hussein took power in 1979, Iraq has engaged in wars with Iran and Kuwait and in two wars with the United States. The years between the wars with the United States, 1991-2003, were characterized by economic sanctions that destroyed the social fabric the wars had missed. In 2003, after major combat operations were complete, the United Nations created the United Nations Assist Mission for Iraq (UNAMI) to prop ... |
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| Inefficient by Design: A Model for Leader Assessment of Organizational Efficiency |
22-May-2008 |
66 pages |
| Authors:
Christopher L Larrabee; ARMY COMMAND AND GENERAL STAFF COLL FORT LEAVENWORTH KS SCHOOL OF ADVANCED MILITARY STUDIES
|
| As the ability of organizations to process information accelerates, and technological advances facilitate ever more rapid decision-making, organizational leaders sacrifice the time once available for careful reflection on the nature of problems and potential resolutions. The phenomenon of globalization is reinforcing the notion that such a sacrifice of time is both necessary and unavoidable. But the very notion that the critical emphasis should be placed on the time available to ... |
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| Joint Attack Munition Systems (JAMS) Project Office Improving Support to the Warfighter |
01-Apr-2008 |
9 pages |
| Authors:
Barry W Beavers; William Ruta; JOINT ATTACK MUNITION SYSTEMS PROJECT OFFICE REDSTONE ARSENAL AL
|
| The Joint Attack Munition Systems (JAMS) Project Office improved support to the warfighter with its implementation of the Life Cycle Management Command (LCMC) concept. LCMC was defined by the Program Executive Office for Missiles and Space as the vision to get products to the soldier faster, make good products even better, minimize life-cycle costs, and enhance the synergy and effectiveness of the Army Acquisition, Logistics and Technology (AL&T) communities. This ... |
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| Energy Losses in Simulated Relativistic Michigan A6 Magnetron with Shaped Cathode |
Apr-2008 |
2 pages |
| Authors:
Peter Mardahl; AIR FORCE RESEARCH LAB KIRTLAND AFB NM DIRECTED ENERGY DIRECTORATE
|
| Recently there has been much research interest in improving magnetron performance by employing various priming techniques, such as shaped cathodes and nonuniform magnetic fields. These priming techniques have been successfully applied to reduce magnetron noise and improve mode-locking and efficiency. Inserting a shaped cathode into the simulated Michigan magnetron yields a maximum efficiency (the radiofrequency (RF) output power for a cycle divided by the current times voltage input for that ... |
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| Improving Naval Shipbuilding Project Efficiency through Rework Reduction |
SEP 2007 |
|
| Authors:
Deborah L. Clark; Donna M. Howell; Charles E. Wilson; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The rising cost of U.S. Naval Ships and the rate of change in technology require a thorough analysis of current shipbuilding practices. The Navy wants the latest and greatest technology, while at the same time keeping overall cost low. Some technologies are obsolete before completion of the ship's design and construction. A design locked in at Critical Design Review (CDR) undergoes multiple modifications prior to ship's delivery. Design changes drive ... |
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| Laboratory Determination of Thermal Protection System Materials Surface Catalytic Properties |
01 JUL 2007 |
33 pages |
| Authors:
Jochen Marschall; SRI INTERNATIONAL MENLO PARK CA MOLECULAR PHYSICS LAB
|
| Different experimental approaches to measuring catalytic reaction efficiencies on thermal protection system materials are reviewed. Special emphasis is given to the theory and application of the diffusion tube side-arm reactor technique. In this technique, reactants diffuse into a dead-end tube and are progressively removed from the gas phase by surface reactions on the walls, establishing unique steady-state concentration profiles along the length of the tube. Reactant loss probabilities are determined ... |
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| Radiometric Characterization of a New Photovoltaic Cell Unit for Powering Modulating Retroreflectors |
19 JUN 2007 |
18 pages |
| Authors:
Xiaolei Zhang; James Murphy; G. C. Gilbreath; NAVAL RESEARCH LAB WASHINGTON DC REMOTE SENSING DIV
|
| We describe the experimental procedures and results of a detailed radiometric characterization of a new photovoltaic (PV) wafer unit intended for powering the Multiple Quantum Well (MQW) Modulating Retroreflector (MRR) using natural sunlight and/or system laser light as energy input, to enable autonomous operation of free-space optical data link using the MQW-MRR. Our initial measurements show that the PV wafer unit has an average power conversion efficiency of 7% to ... |
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| Thrust Efficiency, Energy Efficiency, and the Role of VDF in Hall Thruster Performance Analysis (Preprint) |
29 MAY 2007 |
19 pages |
| Authors:
C. W. Larson; William A. Hargus; Daniel L. Brown; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| A rocket power efficiency equation was written to explicitly account for the effect of the velocity distribution function (VDF) of the propellant jet on the conversion of anode electrical energy to jet kinetic energy. This enabled a mathematically rigorous distinction to be made between thrust efficiency and energy efficiency. In this approach anode thrust efficiency, the commonly reported figure of merit for Hall thrusters, is the product of three utilization ... |
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| Strategic Art and Energy: An Alternative Ends-Ways-Means View |
09 MAY 2007 |
33 pages |
| Authors:
John B. Wissler; ARMY WAR COLL CARLISLE BARRACKS PA
|
| With Hurricane Katrina, Americans tasted of a future defined by constrained energy supplies and a likely worldwide oil production peak sometime in the next 30 years. This paper will consider how energy should be viewed in a strategic context and takes the position that a truly strategic view must focus not only on energy supplies, but also on how and why the military uses that energy, particularly with regard to ... |
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| Future of Power Efficient Processing (BRIEFING CHARTS) |
07-Mar-2007 |
13 pages |
| Authors:
Michael Fritze; DEFENSE ADVANCED RESEARCH PROJECTS AGENCY ARLINGTON VA MICROSYSTEMS TECHNOLOGY OFFICE
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| A Decision Model for Selecting Energy Efficient Technologies for Low-Sloping Roof Tops Using Value-Focused Thinking |
MAR 2007 |
112 pages |
| Authors:
Michael J. McCourt; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| The Air Force has a large inventory of low-sloping built up roofs (BURs) and millions of dollars are spent each year retrofitting these systems. The DOD has been directed to reduce non-renewable energy consumption by using energy-efficient technologies. These two details present a great opportunity to use the open roof space to install energy-efficient roofing technologies. The purpose of this research is to provide Air Force decision makers with a ... |
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| Custom Work Aids for Distributed Command and Control Teams: A Key to Enabling Highly Effective Teams |
Jan-2007 |
23 pages |
| Authors:
Samuel R Kuper; Beth L Giurelli; Sandeep Mulgund; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
|
| This paper presents an approach for designing information technology-based work aids to enable high work efficiency and effectiveness (E&E) for a distributed and networked command and control (C2) team. The authors believe this approach can be utilized to achieve these high-efficiency goals for other C2 teams as well. A common approach to supporting distributed teams is with general purpose collaboration tools (such as chat, whiteboards, file sharing, etc.). Because of ... |
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| Characteristics and Sampling Efficiencies of MicroST Virtual Impactors |
OCT 2006 |
17 pages |
| Authors:
Jana S. Kesavan; Deborah Schepers; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR
|
| The aerosol sampling efficiencies of two prototype MicroST virtual impactors (BigRB and LittleRB) were determined at the U.S. Army Edgewood Chemical Biological Center (ECBC). These virtual impactors are designed to be connected serially to be a two-stage aerosol concentrator. The BigRB was tested at a total air flowrate of 24.5-32.3 Lpm with a minor airflow of 2.5-3.2 Lpm. The LittleRB was tested at a total airflow of 3.2-4.9 Lpm with ... |
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| Evaluation of European District Heating Systems for Application to Army Installations in the United States |
JUL 2006 |
245 pages |
| Authors:
Alexander M. Zhivov; John L. Vavrin; Alfred Woody; Donald Fournier; Stephen Richter; Daniel Droste; Satu Paiho; Jenni Jahn; Reijo Kohonen; ENGINEER RESEARCH AND DEVELOPMENT CENTER CHAMPAIGN IL CONSTRUCTION ENGINEERING RESEARCH LAB
|
| District heating (DH) is much less common in the United States than in Europe, where it is widely accepted as a method for providing safe, efficient, low-cost heating energy to the consumer. This study investigated and evaluated experiences with DH systems in Europe, focusing on systems in Germany and Finland, to offer recommendations for improving U.S. Army DH systems in the Continental United States (CONUS), specifically to evaluate the feasibility ... |
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| Technology Options for Improved Air Vehicle Fuel Efficiency: Executive Summary and Annotated Brief |
MAY 2006 |
81 pages |
| Authors:
Ann Karagozian; Werner Dahm; Ed Glasgow; Roger Howe; Ilan Kroo; Richard Murray; Heidi Shyu; SCIENTIFIC ADVISORY BOARD (AIR FORCE) WASHINGTON DC
|
| As crude oil prices and worldwide competition for fuel continue to increase, there are added pressures on the United States to simultaneously conserve fuel as well as seek new sources of energy for power generation and transportation systems. Within the U.S. military, increasing costs of fuel directly affect the ability to carry out military missions. Hence it is imperative that the Department of Defense, and the Air Force in particular ... |
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| Analysis and Coding for Multiple-Access Channels |
06 MAR 2006 |
6 pages |
| Authors:
Miklos Ruszinko; HUNGARIAN ACADEMY OF SCIENCES BUDAPEST HUNGARY COMPUTER AND AUTOMATION RESEARCH INST
|
| The most important communication channels were investigated in the situation of multiple users. These models do not assume any central intelligence there is no coordination between the transmitters, so fit to the usual conditions of an ad-hoc or sensor network. Better bounds on the minimum code word length and efficient code constructions were achieved for the scenarios, when many independent, partially active transmitters are communicating over a shared medium. These ... |
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| Designing Transportable Collectively Protective Shelters for Thermal Efficiency |
2006 |
16 pages |
| Authors:
Neal M. Riemer; Don Johnson; Bryan Kohn; Scott Matheson; Carl Williams; Bill Gillespie; AIR ARMAMENT CENTER EGLIN AFB FL
|
| This paper discusses different techniques for designing a transportable collective protection shelter that is thermally efficient, meaning that the heating and cooling capacity needed to maintain a comfortable environment is minimized. Two areas of shelter design can be optimized to produce a shelter that is thermally efficient. First, a radiant barrier coating can be applied to either the shelter surface or a liner, or a solar shade can be used ... |
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| An Overview of Data Aggregation Architecture for Real-Time Tracking with Sensor Networks |
2006 |
9 pages |
| Authors:
Tian He; Lin Gu; Liqian Luo; Ting Yan; John A. Stankovic; Sang H. Son; VIRGINIA UNIV CHARLOTTESVILLE DEPT OF COMPUTER SCIENCE
|
| Since sensor nodes normally have limited resources in terms of energy, bandwidth and computation capability, efficiency is a key design goal in sensor network research. As one of techniques to achieve efficiency, data aggregation has been extensively investigated in recent literature. Previous research on data aggregation has demonstrated its effectiveness in reducing traffic, easing congestion and decreasing the energy consumption. However few are actually designed for a realworld application and ... |
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| Efficiently Computing and Updating Triangle Strips for Real-Time |
2006 |
28 pages |
| Authors:
Jihad El-Sana; Amitabh Varshney; Francine Evans; Steven Skiena; Aravind Kalaiah; Elvir Azanli; STATE UNIV OF NEW YORK AT STONY BROOK DEPT OF COMPUTER SCIENCE
|
| Triangle strips are a widely used hardware-supported data-structure to compactly represent and efficiently render polygonal meshes. In this paper, we survey the efficient generation of triangle strips as well as their variants. We present efficient algorithms for partitioning polygonal meshes into triangle strips. Triangle strips have traditionally used a buffer size of two vertices. In this paper, we also study the impact of larger buffer sizes and various queuing disciplines ... |
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| The Effects of A-76 Cost Comparisons on DoD Civilian Education and Training |
2006 |
|
| Authors:
Edward G. Keating; Dina G. Levy; Joy S. Moini; Susan M. Gates; Kristin Leuschner; Candice Riley; Tessa Kaganoff; Catherine H. Augustine; RAND NATIONAL DEFENSE RESEARCH INST SANTA MONICA CA
|
| The Department of Defense (DoD) has made considerable use of the Office of Management and Budget's Circular A-76 cost comparison process (Executive Office of the President, May 29, 2003), under which government employees compete with contractors over who will perform a commercial activity, and there are plans for considerably more A-76 comparisons in the DoD. A-76 has also been used in other parts of the federal government; other levels of ... |
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| Valuing the DoD Process Output |
DEC 2005 |
59 pages |
| Authors:
Petros Bourazanis; Gusnadi; NAVAL POSTGRADUATE SCHOOL MONTEREY CA GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY
|
| The Department of Defense (DoD) is facing the challenge to discover a tool to measure its performance as part of its responsibility to taxpayers. As a public institution that provides a public good to the people, the DoD has difficulties in using the prominent investment financial ratios used by the private sector as a metric of their performance. The problem is that DoD does not generate revenue and simultaneously, in ... |
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| Design of Heterostructures for High Efficiency Thermionic Emission |
NOV 2005 |
7 pages |
| Authors:
Zhixi Bian; Ali Shakouri; CALIFORNIA UNIV SANTA CRUZ ELECTRICAL ENGINEERING DEPT
|
| We use two heterostructure designs to improve the energy conversion efficiency of solid-state thermionic devices. The first method is to use a non-planar heterostructure with roughness in order of electron mean free path. This has some combined benefits of increased effective interface area, and reduced total internal reflection for the electron trajectories arriving at the interface. Monte Carlo simulations of various geometries show that the electrical conductivity and thermoelectric figure ... |
|
| An 18-GHz, 10.9-dBm Fully-Integrated Power Amplifier with 23.5% PAE in 130-nm CMOS |
SEP 2005 |
5 pages |
| Authors:
Changhua Cao; Haifeng Xu; Yu Su; Kenneth K. O; FLORIDA UNIV GAINESVILLE DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
|
| An 18-GHz fully integrated class-E power amplifier with 10.9-dBm saturated output power and 23.5% maximum power added efficiency (PAE) was fabricated in the UMC 130-nm digital complementary metal-oxide semiconductor (CMOS) process. At the saturated output the required input power level is -5dBm and the power amplifier consumes 35mA from V(sub DD)=1.5V. The amplifier is single-ended and includes a 2-stage pre-amplifier and a driver stage. A mode-locking technique exploiting the instability ... |
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| Performance Test Results for the Laser-Powered Microthruster (PREPRINT) |
30 AUG 2005 |
13 pages |
| Authors:
Claude R. Phipps; James R. Luke; Wesley Helgeson; Richard Johnson; PHOTONIC ASSOCIATES SANTA FE NM
|
| Microthrusters are useful for orienting and repositioning small craft above the atmosphere. We report technical results obtained during a successful 5-year program to develop a commercially-viable laser-powered microthruster. Its main advantage is the ability to generate a broad thrust range under programmable electronic control with minimal electrical power. The device applies millisecond-duration diode-laser pulses to a fuel tape to produce an ablation jet. By employing laser-initiated energetic polymers in our ... |
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| New European Apogee Motor -- Advanced Propulsion Technology |
13 JUL 2005 |
3 pages |
| Authors:
Dieter Ehmann; Ulrich Gotzig; Georg Schulte; Steffen Beyer; Stefan Schmidt; EADS SPACE TRANSPORTATION LAMPOLDSHAUSEN (GERMANY)
|
| Apogee motors will transfer large geostationary satellites into their final orbit within the next decade. Approximately 60% of a geostationary satellite's mass is propellant, 90% of which is consumed by the apogee motor. An increase in motor performance and motor efficiency would offer significant mass savings for the satellites. Therefore, an optimum performing apogee motor is still an element of strategic importance for the competitiveness of large geostationary satellites. The ... |
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| An Experimental Analysis of the Relative Efficiency of Alternative Assignment Auction Formats |
23 JUN 2005 |
18 pages |
| Authors:
R. W. Nimon; Ricky Hall; NAVY PERSONNEL RESEARCH STUDIES AND TECHNOLOGY MILLINGTON TN
|
| Basic Structure of the Experiments: (1) Subjects are presented with list of jobs. (2) Total Score = Fitness Score + Bid Score. (3) Optimization across Total Scores determines assignments. (4) For each job the bidder's reservation wage (RW) is given. (5) For the awarded job the subject receives Gamebucks = Bid-RW. (6) Subjects exchange their Gamebucks for US dollars at a pre-announced exchange rate. This is their payment. |
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| Evaluating Operating Room Turnaround Times and Cancellations at Dwight D. Eisenhower Army Medical Center |
10 JUN 2005 |
50 pages |
| Authors:
William L. Amsink; DWIGHT DAVID EISENHOWER ARMY MEDICAL CENTER FORT GORDON GA
|
| Two costly problems in the operating room (OR) are lengthy turnaround times between surgical cases and the waste of resources and OR time due to high cancellation rates. By reducing turnaround time, staff overtime can be reduced and more cases can be scheduled during the day. Archival data were reviewed on 3,727 surgical cases from a U.S. Government medical facility database. This study describes the inefficient use of the current ... |
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| Are Joint Deployment Distribution Operations Centers (JDDOCs) an Effective Instrument for Overcoming Combatant Commanders' Intra-Theater Logistical Challenges |
17 MAY 2005 |
35 pages |
| Authors:
Michael W. Leupold; Bryan Newkirk; NAVAL WAR COLL NEWPORT RI JOINT MILITARY OPERATIONS DEPT
|
| During Operation Desert Storm (ODS) and Operation Enduring Freedom (OEF)/Iraqi Freedom (OIF) (Phase I), the Combatant Commander's logistical management organizational structure proved to be inadequate both in its organizational structure and subject matter expert manning level to execute an efficient logistical support effort. With the waning of Cold War era symmetrical warfare and the emergence of adversaries who attempt to exploit the United States military strength by employing asymmetrical warfare, ... |
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| Fuel Optimal Low Thrust Trajectories for an Asteroid Sample Return Mission |
MAR 2005 |
75 pages |
| Authors:
Jack W. Rust; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This thesis explores how an Asteroid Sample Return Mission might make use of solar electric propulsion to send a spacecraft on a journey to the asteroid 1989ML and back. It examines different trajectories that can be used to get an asteroid sample return or similar spacecraft to an interplanetary destination and back in the most fuel-efficient manner. While current plans call for keeping such a spacecraft on the asteroid performing ... |
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| Detection Limits for Nanoscale Biosensors |
15 FEB 2005 |
6 pages |
| Authors:
Paul E. Sheehan; Lloyd J. Whitman; NAVAL RESEARCH LAB WASHINGTON DC CHEMISTRY DIV
|
| We examine through analytical calculations and finite element simulations how the detection efficiency of disk and wire-like biosensors in unmixed fluids varies with size from the micrometer to nanometer scales. Specifically, we determine the total flux of DNA-like analyte molecules on a sensor as a function of time and flow rate for a sensor incorporated into a microfluidic system. In all cases, sensor size and shape profoundly affect the total ... |
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| Sampling Efficiency Measurement Methods for Aerosol Samplers |
JAN 2005 |
21 pages |
| Authors:
Jana S. Kesavan; Jerold R. Bottiger; Robert W. Doherty; EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD RESEARCH AND TECHNOLOGY DIR
|
| Aerosol samplers and concentrators are characterized at the U.S. Army Edgewood Chemical Biological Center. The characterization methods are summarized and include (1) monodisperse fluorescent/nonfluorescent Polystyrene Latex (PSL) microspheres with fluorometric analysis or Coulter Multisizer Analysis; (2) polydisperse solid aluminum oxide particles with Aerodynamic Particle Sizer (APS) analysis or Coulter Multisizer Analysis; (3) liquid fluorescent oleic acid particles with fluorometric analysis; and (4) bioparticles with Coulter Multisizer, culturing, enzyme linked immunosorbent ... |
|
| Optimized Performance GaAs-Based Diode Lasers: Reliable 800-nm 125W Bars and 83.5% Efficient 975-nm Single Emitters |
2005 |
6 pages |
| Authors:
Paul Crump; Jun Wang; Trevor Crump; Shiguo Zhang; Mike Grimshaw; Weimin Dong; Mark DeFranza; Suhit Das; Mark DeVito; Jason Farmer; NLIGHT PHOTONICS CORP VANCOUVER WA
|
| GaAs-based high power diode bars produce wavelengths in the range of 780 to 980 nm and are widely used for pumping a broad range of rare earth doped solid-state lasers. As the markets for these laser systems mature, diode lasers that operate at higher power levels, greater overall efficiency, and higher reliability are in high demand. In this paper we report efficiencies of up to 83.5% in the 9xx-nm band, ... |
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| Energy-Aware Broadcasting and Multicasting in Wireless Ad Hoc Networks: A Cross-Layering Approach |
02 JUN 2004 |
21 pages |
| Authors:
Jeffrey E. Wieselthier; Gam D. Nguyen; Anthony Ephremides; NAVAL RESEARCH LAB WASHINGTON DC INFORMATION TECHNOLOGY DIV
|
| The wireless networking environment presents formidable challenges to the study of broadcasting (one-to-all) and multicasting (one-to-many) problems, especially when energy-aware operation is required. To address the specific problem of energy-aware tree construction in wireless ad hoc networks, we have developed the Broadcast Incremental Power (BIP) and Multicast Incremental Power (MIP) algorithms. Our algorithms are based on a crosslayering approach in which tree structure and communication range are chosen jointly. We ... |
|
| Aligning Salary Expense and Workload Output In a Complex Military Medical System |
JUN 2004 |
193 pages |
| Authors:
Randy K. Bills; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The National Naval Medical Center (NNMC), Bethesda, Maryland, set as a strategic goal the improvement of internal efficiency among its many clinical activities. Clinical services lacked the ability to improve their statistical process, which relied on workload and expense data. Since the data systems had removed provider identifiers, it was impossible to produce data on provider productivity and efficiency. Numerous efforts to improve the clinical staff's efficiency were unsuccessful because ... |
|
| Improving the Numerical Efficiency of Generalized Multipole Technique by Non-Redundant Multipole Choices |
23 APR 2004 |
7 pages |
| Authors:
A. K. Bandyopadhyay; C. Tomassoni; M. Mongiardo; A. S. Omar; OTTTO-VON-GUERICKE-UNIVERSITAT MAGDEBURG (GERMANY)
|
| The Generalized Multipole Technique, due to its flexibility, is used in a variety of cases for the analysis of electromagnetic structures. This method is generally based on a multiple multipole expansion and a point matching technique. The numerical conditioning of the matrices involved in this analysis is strongly dependent on the matching point and the multipole distribution. In this contribution, we use the well-known Singular Value Decomposition to investigate systematically ... |
|
| Luminous Efficiency Functions at Higher Intensities |
APR 2004 |
66 pages |
| Authors:
Lawrence K. Harrington; MISSOURI UNIV-ST LOUIS
|
| Two psychophysical measurement techniques, flicker photometry and successive heterochromatic brightness matching, were used to measure changes in luminance efficiency functions with increasing levels of light adaptation. Both measurement techniques were performed using the same optical system and the same seven healthy adults as subjects. Measurements were taken at four reference stimulus intensities, 1, 10, 100 and 1000 foot-lamberts. Luminous efficiency was found to depend on both the technique and the ... |
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| VP3: Using Vertex Path and Power Proximity for Energy Efficient Key Distribution |
2004 |
6 pages |
| Authors:
Loukas Lazos; Javier Salido; Radha Poovendran; WASHINGTON UNIV SEATTLE DEPT OF ELECTRICAL ENGINEERING
|
| This paper investigates the problem of energy-efficient key distribution for securing multicast communications in wireless ad hoc networks. Recently, the authors showed that a cross-layer design approach for key distribution, incorporating network layer (routing) as well as physical layer (energy) parameters, leads to energy savings. They also showed that heuristics are needed to reduce computational complexity. In this paper, the authors show that further reduction in energy expenditure is achieved ... |
|
| Cross-Layer Design for Energy-Efficient Secure Multicast Communications in Ad Hoc Networks |
2004 |
8 pages |
| Authors:
Loukas Lazos; Radha Poovendran; WASHINGTON UNIV SEATTLE DEPT OF ELECTRICAL ENGINEERING
|
| The authors consider the problem of secure multicast in an energy-constrained wireless environment. They present an analytical formulation of the energy expenditure associated with the communication overhead of key management, and highlight its dependence on network topology and key distribution method. They show that the optimal solution of this formulation does not scale with multicast group size and propose a sub-optimal, cross-layer, low-complexity algorithm for energy-efficient key distribution. Simulation studies ... |
|
| Efficient Closed Pattern Mining in the Presence of Tough Block Constraints |
25 NOV 2003 |
15 pages |
| Authors:
Krishna Gade; Jianyong Wang; George Karypis; MINNESOTA UNIV MINNEAPOLIS DEPT OF COMPUTER SCIENCE
|
| In recent years, various constrained frequent pattern mining problem formulations and associated algorithms have been developed that enable the user to specify various itemset based constraints that better capture the underlying application requirements and characteristics. In this paper we introduce a new class of block constraints that determine the significance of an itemset pattern by considering the dense block that is formed by the pattern's items and its associated set ... |
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| Contract Closeout (A) |
30-Sep-2003 |
48 pages |
| Authors:
David V Lamm; NAVAL POSTGRADUATE SCHOOL MONTEREY CA GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY
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| It was the 10th of January 2004 and Jim Ross was contemplating how he was going to resolve a very tough issue. He had been working this problem for some time now but it just wasn't improving. Jim is an Administrative Contracting Officer (ACO) in the Defense Contract Management Agency (DCMA) located in Sunnyvale, California. His problem is a growing backlog of contracts for which contractors had finished performance and ... |
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| Transformation in Department of Defense Contract Closeout |
Jun-2003 |
30 pages |
| Authors:
Christopher Parker; Michael Busansky; NAVAL POSTGRADUATE SCHOOL MONTEREY CA GRADUATE SCHOOL OF BUSINESS AND PUBLIC POLICY
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| Two short years ago, mentioning the words contract closeout would have drawn a critical eye or a scoffing laugh out of many in the acquisition community. These critics would never have believed that contract closeout was destined to become a priority at the highest levels of the Department of Defense (DoD). Yet, in the past few years there has been a reversal in the way acquisition professionals view contract closeout. ... |
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| A Novel Power-Efficient Broadcast Routing Algorithm Exploiting Broadcast Efficiency |
2003 |
6 pages |
| Authors:
Intae Kang; Radha Poovendran; WASHINGTON UNIV SEATTLE DEPT OF ELECTRICAL ENGINEERING
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| It has been shown that the problem of finding a broadcast routing tree with minimum total transmit power is NP-hard. Hence, developing a heuristic power-efficient algorithm is crucial. The seminal work in this area is the well-known Broadcast Incremental Power (BIP) algorithm with a recent addition called Embedded Wireless Multicast Advantage (EWMA) algorithm. In this paper, the authors present yet another novel power-efficient algorithm for broadcast routing tree construction called ... |
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