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Hill R.R.,Air Force Institute of Technology | Cho Y.K.,Ministry of National Defense | Moore J.T.,Air Force Institute of Technology
Computers and Operations Research | Year: 2012

This paper introduces new problem-size reduction heuristics for the multidimensional knapsack problem. These heuristics are based on solving a relaxed version of the problem, using the dual variables to formulate a Lagrangian relaxation of the original problem, and then solving an estimated core problem to achieve a heuristic solution to the original problem. We demonstrate the performance of these heuristics as compared to legacy heuristics and two other problem reduction heuristics for the multi-dimensional knapsack problem. We discuss problems with existing test problems and discuss the use of an improved test problem generation approach. We use a competitive test to highlight the performance of our heuristics versus the legacy heuristic approaches. We also introduce the concept of computational versus competitive problem test data sets as a means to focus the empirical analysis of heuristic performance. © 2011 Elsevier Ltd. All rights reserved.


Chen M.-J.,National Chiao Tung University | Lee C.-C.,National Chiao Tung University | Cheng K.-H.,Ministry of National Defense
IEEE Transactions on Electron Devices | Year: 2011

Self-consistently solving the Schrödinger and Poisson's equations in the six-band k · p context can yield the valence-band structure in the inversion layers of pMOSFETs. In this numerically demanding process, the central processing unit (CPU) time is extraordinarily long. To overcome the hurdle, we construct a novel computational accelerator to intrinsically boost a self-consistent six-band k · p simulation. This accelerator comprises a triangular-potential-based six-band k · p simulator, a hole effective mass approximation (EMA) technique, and an electron analogy version of the self-consistent Schrödinger and Poisson's equations solver. The outcome of the accelerator furnishes the initial solution of the confining electrostatic potential and is likely close to the realistic one, which is valid for different temperatures, substrate doping concentrations, inversion hole densities, and surface orientations. The results on (001) and (110) substrates are supported by those published in the literature. The overall CPU time is reduced down to around 8% of that without the accelerator. This is the first successful demonstration of the EMA in the self-consistent hole subband structure calculation. The application of the proposed accelerator to more general situations is projected as well. © 2011 IEEE.


Hsu C.-Y.,National Chiao Tung University | Chang H.-G.,Ministry of National Defense | Chen M.-J.,National Chiao Tung University
IEEE Transactions on Electron Devices | Year: 2011

For metal-gate high-k dielectrics, there is a transition region in the electron gate tunneling current Ig, as characterized by a plot of dlnIg/dVg versus Vg. In this paper, we systematically construct a new fitting over the region, which can accurately determine material parameters, including metal work function, high-k electron affinity, and tunneling effective masses of electrons. First of all, a calculation of gate current due to electron direct tunneling and/or FowlerNordheim tunneling from an inversion layer is performed, yielding the guidelines of the fitting. Experimental samples are presented with n-channel metaloxidesemiconductor field-effect transistors having low effective oxide thickness (1.4 nm) TaC/HfSiON/SiON gate stacks. Underlying material parameters are extracted accordingly and remain valid for higher temperature and gate voltage. We also demonstrate that a conventional method without a dlnI g/dVg fitting might lead to erroneous results. Thus, the dlnIg/dVg fitting is crucial to metal-gate high-k material parameter assessment. © 2011 IEEE.


News Article | February 17, 2017
Site: www.marketwired.com

Brown Comes Out of Retirement to Help Active/Retired Members of the Military and First Responders Combat Chemical Dependency and Psychological Disorders SAN ANTONIO, TX--(Marketwired - February 17, 2017) - Warriors Heart, the Texas Hill Country-based private treatment facility serving active and veteran members of the military and first responders, today named retired U.S. Army Colonel Joe Brown the organization's executive director. "Colonel Brown is coming out of retirement to join the front lines against chemical dependency and related psychological disorders so many of our active and retired members of the military and first responders suffer due to the traumas they have experienced," said Josh Lannon, co-founder of Warriors Heart. "Joe's military background gives him a level of understanding and rapport that will be invaluable to our mission of helping these national heroes." Retired U.S. Army Colonel Joe Brown served more than 25 years in active duty, specializing in operational logistics and medical service. He also served as deputy to the director of logistics in Iraq, supporting more than 144,000 coalition forces of the Combined Joint Task Force-Seven during Operation Iraqi Freedom. Colonel Brown also commanded the 16th Corps Support Group, consisting of 3,500 soldiers who supported the U.S. Army's V Corps during major combat operations in Iraq in 2003. Colonel Brown also served as Chief, Ambulatory Care Support Branch at the Frankfurt Regional Medical Center in Germany and Health Care Administrator at Darmstadt Health Clinic, which supported over 40,000 military and family members. After retiring from the Army in 2004, Brown was a logistics consultant for Northrop Grumman Corporation, providing consulting services to the Romanian Ministry of National Defense in Bucharest, Romania. From 2005 to 2015, he was an associate partner in IBM Corporation's Global Business Services in support of Army and U.S. Department of Defense security missions. "I could no longer sit back and be silent as more than 20 veterans commit suicide every day," said Brown. "We are losing more veterans to alcoholism, drug addiction and suicide than we are in combat. The VA is backlogged, and our veterans are not getting the help they need and deserve." Warriors Heart is a 40-bed licensed and accredited treatment center dedicated to helping adult men and women 18 and older who suffer from chemical dependence and co-occurring psychological disorders related to post-traumatic stress disorder, moral grief/injury, anxiety, depression, etc., or the psychological effects of mild traumatic brain injury. Located in a rustic ranch setting in the Texas Hill Country northwest of San Antonio, Warriors Heart focuses specifically on helping individuals (active and veteran) who protect and serve the United States and its citizens -- the U.S. military, as well as first responders, including police and law enforcement officers, firefighters, paramedics, and civilian warriors. Warriors Heart offers drug and alcohol treatment programs, PTSD and MTBI therapy, and inpatient and outpatient long-term sober living services. Located within easy driving distance from Houston and Austin, Warriors Heart facilitates healing with dignity and respect in a private, home-like, and judgment-free environment. Statistics show that many people try to cope with their PTSD symptoms by drinking heavily or using drugs. According to the National Center for PTSD, there is a strong relationship between PTSD and substance abuse disorder (SUD) in both civilian and military populations, as well as for both men and women. About one in 10 soldiers returning from the wars in Iraq and Afghanistan have a problem with alcohol or drugs. Similar numbers can be found among first responders, who face horrors in their work most of us cannot imagine. In helping everyday people in the worst of times, they witness death, destruction and much of the darkest side of human nature -- and first responders today seem to be exposed to more trauma than ever before. Service to country and to our nation's warriors is a charge that runs deep in the blood of Brown and his entire family. In addition to his own military service, Brown is the father of two sons who currently serve in the military -- one in the Army and one in the Navy. His wife, Rena, is an addiction nurse at Warriors Heart. "Joe had devoted his entire adult life to taking care of our nation's courageous warriors -- those who have served and sacrificed so much and have earned a full measure of honor, dignity and respect," said Warriors Heart co-founder Lisa Lannon. "We are grateful for his willingness to be directly involved in the important, life-changing work we are doing at Warriors Heart every day." Warriors Heart provides private treatment to adult men and women 18 and older seeking inpatient and outpatient treatment for chemical dependency and co-occurring psychological disorders related to post-traumatic stress disorder or the psychological effects of mild traumatic brain injury. Headquartered in the Texas Hill Country northwest of San Antonio, Warriors Heart treats individuals (active and veteran) who protect and serve the United States and its citizens -- the U.S. military, as well as first responders, including police and law enforcement, firefighters, paramedics and civilian warriors. Warriors Heart was founded by Josh and Lisa Lannon, who have built and operated six substance abuse treatment centers since 2002 and Tom Spooner, retired Army Special Forces. Warriors Heart is fully licensed by the Texas State Department of Health Services and Joint Commission Accredited. For more information, visit www.WarriorsHeart.com.


Neamtu C.,Ministry of National Defense | Gavriloaia M.-R.,University of Bucharest | Gavriloaia G.,University of Pitesti
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2012

The purpose of this paper is to present a new method for evaluation of 3D object shapes which are inside of different environments, and a direct visual contact is not possible. High resolution sensors could solve this kind of problem, mainly by inverse electromagnetic scattering using antenna arrays or synthetic apertures. A cheaper solution is to radiate acoustic field inside of the searched environment. The object detection is realized when the level of received signal exceeds a certain value. The object shape could be appreciated by analyze of 10 consecutive resonant frequencies. Spectral distribution of the resonant frequencies represents the object signature, and it is related to spatial object dimensions. For a given object, this spectral distribution could show how large the object is, in what way the outer surface is smooth or rough or how large the roughness is. The simulation results for three types of objects: pyramid, sphere, and ellipsoid cavities, smooth and rough are presented. Two roughnesses were selected for each object. The resonant frequencies of different objects could be stored and used for medical application (for instance, diagnosis of a tissue whether it is benign or malignant), mine detection buried in ground or evaluation of the different substances filling up the buried objects. © 2012 SPIE.


Wai R.-J.,Yuan Ze University | Lin C.-Y.,Ministry of National Defense | Liaw J.-J.,Yuan Ze University | Chang Y.-R.,Institute of Nuclear Energy Research of Taiwan
IEEE Transactions on Industrial Electronics | Year: 2011

A newly designed zero-voltage-switching (ZVS) multi-input converter is proposed in this paper. The converter can boost the different voltages of two power sources to a stable output voltage. An auxiliary circuit is employed for achieving turn-on ZVS of all switches in the proposed converter. According to various situations, the operational states of the proposed converter can be divided into two states, including a single-power-supply and a dual-power-supply state. In the dual-power-supply state, the input circuits connected in series together with the designed pulsewidth modulation can greatly reduce the conduction loss of the switches. In addition, the effectiveness of the designed circuit topology and the ZVS properties are verified by experimental results, and the goal of high-efficiency conversion can be obtained. © 2011 IEEE.


Wai R.-J.,Yuan Ze University | Lee J.-D.,National formosa University | Chuang K.-L.,Ministry of National Defense
IEEE Transactions on Industrial Electronics | Year: 2011

This paper focuses on the design of a real-time particle-swarm- optimization-based proportional-integral-differential (PSO-PID) control scheme for the levitated balancing and propulsive positioning of a magnetic-levitation (maglev) transportation system. The dynamic model of a maglev transportation system, including levitated electromagnets and a propulsive linear induction motor based on the concepts of mechanical geometry and motion dynamics, is first constructed. The control objective is to design a real-time PID control methodology via PSO gain selections and to directly ensure the stability of the controlled system without the requirement of strict constraints, detailed system information, and auxiliary compensated controllers despite the existence of uncertainties. The effectiveness of the proposed PSO-PID control scheme for the maglev transportation system is verified by numerical simulations and experimental results, and its superiority is indicated in comparison with PSO-PID in previous literature and conventional sliding-mode (SM) control strategies. With the proposed PSO-PID control scheme, the controlled maglev transportation system possesses the advantages of favorable control performance without chattering phenomena in SM control and robustness to uncertainties superior to fixed-gain PSO-PID control. © 2011 IEEE.


Wai R.-J.,Yuan Ze University | Lin C.-Y.,Ministry of National Defense
IEEE Transactions on Industrial Electronics | Year: 2011

This paper focuses on the design of a dual active low-frequency ripple control for a clean-energy power-conditioning mechanism with an aim to achieve both the alleviation of the low-frequency current ripple of clean-energy sources (e.g., solar photovoltaic, fuel cell, etc.) and the improvement of the ac power quality of a power conditioner. First, a simplified circuit for representing both the current-ripple phenomena at the high-voltage bus and the polluted ac output terminal inside a general power conditioner, including a dc-dc converter and a dc-ac inverter, is derived, and the dynamic model of a dual active low-frequency ripple control circuit is analyzed. Moreover, two adaptive linear neural networks are taken as neural filters to generate the compensation current commands, and an adaptive total sliding-mode controller is designed to manipulate the ripple control circuit for injecting respective suitable compensation currents into the high-voltage bus and the ac output terminal of the conditioner. In addition, the effectiveness of the proposed dual active low-frequency ripple control framework is verified by numerical simulations and experimental results. © 2006 IEEE.


Kim B.-K.,Ministry of National Defense | Kim Y.-D.,Korea Advanced Institute of Science and Technology
Computers and Industrial Engineering | Year: 2011

We consider an operations planning problem in a military aviation unit that performs a number of flight missions with multiple identical aircrafts. The problem is to assign the flight missions to the aircrafts and to schedule these assigned missions on each aircraft. Sequence-dependent setup times are required between the missions, and multiple aircrafts may be needed for a mission, but the aircrafts assigned to the same mission should start the mission simultaneously. We develop heuristic algorithms for the problem with the objective of minimizing makespan, i.e., the time by which all the missions have been completed. For evaluation of the performance of the algorithms, a series of computational tests was performed on a number of problem instances, and results show that the proposed algorithms give good or near optimal solutions in a reasonable amount of time. © 2011 Elsevier Ltd. All rights reserved.


Lee B.-J.,Ministry of National Defense | Yang C.W.,Clarion University of Pennsylvania | Yang C.W.,National Chung Cheng University | Huang B.-N.,National Chung Cheng University
Energy Economics | Year: 2012

Applying sector stock prices and oil prices in 1991:01-2009:05 from the G7 countries we find oil price shocks do not significantly impact the composite index in each country. However, stock price changes in Germany, the UK and the US were found to lead oil price changes. As for the interaction between oil price changes and sector stock price changes, we find short-run negative causal relationships: 4 of 7 sector index returns were impacted by oil price changes in Germany, 2 in the US and 1 in France. In particular, stock returns of information technology and consumer staples sectors were found to be impacted most by oil price shocks, followed by financial, utilities and transportation sectors. In terms of causality from sector stock price changes to oil price changes, we find stock price changes lead oil price changes in 8 of 9 sectors in Germany, most in the G7 countries followed by the UK, Italy, France, Canada and the US. No such a causal relationship, however, is found for Japan. With respect to specific sectors, stock price changes in consumer staples and materials sectors were impacted most significantly by oil price changes followed by transportation, financial, energy, health care, industrials, utilities, information technology and telecommunication sectors with the exception of consumer discretionary sector. In addition, short term stock price changes are found to lead positively oil price changes. © 2012 Elsevier B.V.

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