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Full-Text Articles in Engineering

Efficient Non-Coding Rna Gene Searches Through Classical And Evolutionary Methods, Jennifer Smith Dec 2008

Efficient Non-Coding Rna Gene Searches Through Classical And Evolutionary Methods, Jennifer Smith

Jennifer A. Smith

Successful non-coding RNA gene searching requires examination of long-range intramolecular base pairing possibilities. This results in search algorithms with extremely long run times such that large-scale use of the algorithms often becomes computationally infeasible. Methods for the efficient search of the solution space are examined. A review of the standard dynamic-programming covariance model search algorithm is given. An analysis of the statistically probable regions of the search space is undertaken and a method of limiting the traditional dynamic-programming algorithm to this region is shown. An alternative search method using a Genetic Algorithm (GA) which favours the probable region of the …


Quranic Verse Recitation Recognition Module For Educational Programme, Noor Jamaliah Ibrahim, Zulkifli Mohd Yusoff, Zaidi Razak Nov 2008

Quranic Verse Recitation Recognition Module For Educational Programme, Noor Jamaliah Ibrahim, Zulkifli Mohd Yusoff, Zaidi Razak

Noor Jamaliah Ibrahim

In the process of learning al-Quran, reciters are required to learn al-Quran through the manual method of Quran reading skills of talaqqi and musyafahah method. These methods are described as face to face learning process between students and teachers (Mudarris), where listening, correction of al-Quran recitation and repetition of the correct al-Quran recitation takes place. The reason behind this method is to allow Mudarris to check the Tajweed rules of the Quran recitation in real time. However, the current methods of Quran recitation are believed become unattractive and less effective to be implemented, especially for j-QAF students. Focus on j-QAF …


Nano-Structured Materials For Imaging Polarimetry, Andrew Sarangan Oct 2008

Nano-Structured Materials For Imaging Polarimetry, Andrew Sarangan

Andrew Sarangan

No abstract provided.


Collision-Tolerant Transmission With Narrow-Beam Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu, Bo Li Oct 2008

Collision-Tolerant Transmission With Narrow-Beam Antennas, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu, Bo Li

Hong-Ning Dai

The application of directional antennas in wireless ad hoc networks brings numerous benefits, such as increased spatial reuse and mitigated interference. Most MAC protocols with directional antennas are based on the RTS/CTS mechanism which works well in wireless ad hoc networks using omni-directional antennas. However, RTS/CTS frames cannot mitigate the interference completely. Besides, they also contribute a lot to the performance overhead. This paper studies the problem from a new perspective. We have found that the transmission success probability under directional transmission and directional reception is quite high when the antenna beamwidth is quite narrow. Motivated by the analytical results, …


Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines Oct 2008

Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines

Dr. Et-touhami Es-sebbar

In this paper we compare two different discharges that can be obtained in a DBD configuration, that is to say the filamentary discharge (usual regime in atmospheric DBD) with the Atmospheric Pressure Townsend Discharge (APTD), which is a homogeneous regime obtained in nitrogen atmosphere. The aim is to help in the understanding of the processes which control the transition from one regime to the other. To do so, the discharge is characterized through electrical measurements, coupled with optical diagnostics among which Laser Induced Fluorescence (LIF) for radical density measurements. The influence of the addition of small quantities of additives on …


Cut Part Count And Increase Dynamic Range In The Hybrid Coupled Attenuator, Chin-Leong Lim Sep 2008

Cut Part Count And Increase Dynamic Range In The Hybrid Coupled Attenuator, Chin-Leong Lim

Chin-Leong Lim

Modern digital modulation formats are generally phase-sensitive. Therefore, the variable attenuators in digital wireless equipment should exhibit minimal phase variation over attenuation. The hybrid coupled attenuator (HCA) has substantially less phase variation than the competing constant-impedance attenuators such as the Pi and the Bridged-T. At microwave frequencies, HCA implementations tend to suffer from reduced dynamic (attenuation) range due to component parasitics, especially when plastic-packaged PIN diodes are selected to lower cost. To maximize the dynamic range in a low-cost 1.9 GHz HCA , we first identified the critical components and then compensated for their deleterious effect. This paper describes the …


A Framework For Systematic Benchmarking Of Monitoring And Diagnostic Systems, Tolga Kurtoglu, Ole J. Mengshoel, Scott Poll Sep 2008

A Framework For Systematic Benchmarking Of Monitoring And Diagnostic Systems, Tolga Kurtoglu, Ole J. Mengshoel, Scott Poll

Ole J Mengshoel

In this paper, we present an architecture and a formal framework to be used for systematic benchmarking of monitoring and diagnostic systems and for producing comparable performance assessments of different diagnostic technologies. The framework defines a number of standardized specifications, which include a fault catalog, a library of modular test scenarios, and a common protocol for gathering and processing diagnostic data. At the center of the framework are 13 benchmarking metric definitions. The calculation of metrics is illustrated on a probabilistic model-based diagnosis algorithms utilizing Bayesian reasoning techniques. The diagnosed system is a real-world electrical power system, namely the Advanced …


Valley Splitting In Si Quantum Dots Embedded In Sige, Srikant Srinivasan Sep 2008

Valley Splitting In Si Quantum Dots Embedded In Sige, Srikant Srinivasan

Srikant Srinivasan

We examine energy spectra of Si quantum dots embedded in Si0.75Ge0.25 buffers using atomistic numerical calculations for dimensions relevant to qubit implementations. The valley degeneracy of the lowest orbital state is lifted and valley splitting fluctuates with monolayer frequency as a function of the dot thickness. For dot thicknesses ≤ 6 nm, valley splitting is found to be >150 μeV. Using the unique advantage of atomistic calculations, we analyze the effect of buffer disorder on valley splitting. Disorder in the buffer leads to the suppression of valley splitting by a factor of 2.5; the splitting fluctuates with ≈ 20 μeV …


Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi Sep 2008

Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


A Heuristic Scheduling Scheme In Multiuser Ofdma Networks, Zheng Sun, Zhiqiang He, Ruochen Wang, Kai Niu Aug 2008

A Heuristic Scheduling Scheme In Multiuser Ofdma Networks, Zheng Sun, Zhiqiang He, Ruochen Wang, Kai Niu

Zheng Sun

Conventional heterogeneous-traffic scheduling schemes utilize zero-delay constraint for real-time services, which aims to minimize the average packet delay among real-time users. However, in light or moderate load networks this strategy is unnecessary and leads to low data throughput for non-real-time users. In this paper, we propose a heuristic scheduling scheme to solve this problem. The scheme measures and assigns scheduling priorities to both real-time and non-real-time users, and schedules the radio resources for the two user classes simultaneously. Simulation results show that the proposed scheme efficiently handles the heterogeneous-traffic scheduling with diverse QoS requirements and alleviates the unfairness between real-time …


Using Bayesian Networks For Candidate Generation In Consistency-Based Diagnosis, Sriram Narasimhan, Ole J. Mengshoel Aug 2008

Using Bayesian Networks For Candidate Generation In Consistency-Based Diagnosis, Sriram Narasimhan, Ole J. Mengshoel

Ole J Mengshoel

Consistency-based diagnosis relies on the computation of discrepancies between model predictions and sensor observations. The traditional assumption that these discrepancies can be detected accurately (by means of thresholding for example) is in many cases reasonable and leads to strong performance. However, in situations of substantial uncertainty (due, for example, to sensor noise or model abstraction), more robust schemes need to be designed to make a binary decision on whether predictions are consistent with observations or not. However, if an accurate binary decision is not made, there are risks of occurrence of false alarms and missed alarms. Moreover when multiple sensors …


Design A Pin Diode Switch For High-Linearity Applications, Chin-Leong Lim Jul 2008

Design A Pin Diode Switch For High-Linearity Applications, Chin-Leong Lim

Chin-Leong Lim

This paper describes the semiconductor technology, packaging and characterization of a new PIN diode for switching WCDMA signal up to 10W. PIN semiconductor technology was picked as the basis for this switch because of the various performance and reliability advantages that can be had. A model for the PIN diode is generated based on the measured RF performance. How the various model parameters affect the RF performance is also discussed. This is followed by an application description of a 2.0 GHz switch based on the said model and a discussion of some circuit changes to further improve the performance. The …


Investigation Of Stun Guns As Intentional Electromagnetic Interference (Emi) Sources, George H. Baker, Ryan C. Tuttle Jul 2008

Investigation Of Stun Guns As Intentional Electromagnetic Interference (Emi) Sources, George H. Baker, Ryan C. Tuttle

George H Baker

Determined malefactors have demonstrated the use of common systems as effective weapons against civilian infrastructures, e.g. commercial jetliners used as kinetic weapons and cell phones used to trigger explosive devices. This undergraduate research project investigated the possibility of using readily available stun gun devices for electro-magnetic interference with or disruption of personal computers. At present, the system effects of high power electromagnetic sources are well recognized by world scientific and military communities. Former CIA Director John Deutch has said that, "the electron is the ultimate precision-guided weapon."1 There has been much research on the deleterious effects of pulsed voltages and …


Investigation Of Stun Guns As Intentional Electromagnetic Interference (Emi) Sources, George H. Baker, Ryan C. Tuttle Jul 2008

Investigation Of Stun Guns As Intentional Electromagnetic Interference (Emi) Sources, George H. Baker, Ryan C. Tuttle

George H Baker

Because the operation and control of most critical infrastructures are highly dependent on electronics, it is important to understand the vulnerability of those electronics to intentional electromagnetic interference (EMI). The possibility of interference using readily available consumer devices is a particular concern. We investigated the feasibility and effectiveness of using compact stun guns to intentionally interfere with electronic systems. Test articles included individual computers and computers networked through a central hub. 60KV and 600KV devices were used in the experiments. Results indicate that stun guns are effective in disabling digital electronic systems.


Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines Jul 2008

Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines

Dr. Et-touhami Es-sebbar

No abstract provided.


Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau Jul 2008

Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau

Dr. Et-touhami Es-sebbar

No abstract provided.


S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin Jul 2008

S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin

Dr. Et-touhami Es-sebbar

No abstract provided.


Modeling Of Fermentation Processes Using Online Kernel Learning Algorithm, Yi Liu Jul 2008

Modeling Of Fermentation Processes Using Online Kernel Learning Algorithm, Yi Liu

Dr. Yi Liu

No abstract provided.


Adaptive Control Of A Class Of Nonlinear Discrete-Time Systems With Online Kernel Learning, Yi Liu Jul 2008

Adaptive Control Of A Class Of Nonlinear Discrete-Time Systems With Online Kernel Learning, Yi Liu

Dr. Yi Liu

No abstract provided.


Report Of The Commission To Assess The Threat To The United States From Emp Attack: Critical National Infrastructures, William R. Graham Jul 2008

Report Of The Commission To Assess The Threat To The United States From Emp Attack: Critical National Infrastructures, William R. Graham

George H Baker

The physical and social fabric of the United States is sustained by a system of systems; a complex and dynamic network of interlocking and interdependent infrastructures (“critical national infrastructures”) whose harmonious functioning enables the myriad actions, transactions, and information flow that undergird the orderly conduct of civil society in this country. The vulnerability of these frastructures to threats — deliberate, accidental, and acts of nature — is the focus of greatly heightened concern in the current era, a process accelerated by the events of 9/11 and recent hurricanes, including Katrina and Rita. This report presents the results of the Commission’s …


Rf Applications Of Pin Diodes, Chin-Leong Lim Jun 2008

Rf Applications Of Pin Diodes, Chin-Leong Lim

Chin-Leong Lim

PIN diodes are the ubiquitous "nuts & screws" components that hold together RF equipment as varied as the television, radio, 2-way radios, WLAN equipment etc. This talk covers PIN diode characteristics and RF applications such as switches, attenuators and limiters. Performance improvement techniques will also be discussed.


Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi Jun 2008

Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza Jun 2008

Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza

Nipun Sinha

This work reports on piezoelectric Aluminum Nitride (AlN) based dual-beam RF MEMS switches that have been monolithically integrated with AlN contour-mode resonators. The dual-beam switch design presented in this paper intrinsically compensates for the residual stress in the deposited films, requires low actuation voltage (5-20 V), facilitates active pull-off to open the switch and fast switching times (1 to 2 µsec). This work also presents the combined response (cascaded S-parameters) of a resonator and a switch that were co-fabricated on the same substrate. The response shows that the resonator can be effectively turned on and off by the switch. A …


Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza Jun 2008

Dual Beam Actuation Of Piezoelectric Aln Rf Mems Switches Integrated With Aln Contour-Mode Resonators, Nipun Sinha, Rashed Mahamameed, Chengjie Zuo, Marcelo B. Pisani, Carlos R. Perez, Gianluca Piazza

Marcelo B Pisani

This work reports on piezoelectric Aluminum Nitride (AlN) based dual-beam RF MEMS switches that have been monolithically integrated with AlN contour-mode resonators. The dual-beam switch design presented in this paper intrinsically compensates for the residual stress in the deposited films, requires low actuation voltage (5-20 V), facilitates active pull-off to open the switch and fast switching times (1 to 2 µsec). This work also presents the combined response (cascaded S-parameters) of a resonator and a switch that were co-fabricated on the same substrate. The response shows that the resonator can be effectively turned on and off by the switch. A …


Mira V: An Integrated System For Minimally Invasive Robot-Assisted Lung Brachytherapy, A. Trejos, A. Lin, S. Mohan, H. Bassan, C. Edirisinghe, R. Patel, C. Lewis, E. Yu, A. Fenster, R. Malthaner Apr 2008

Mira V: An Integrated System For Minimally Invasive Robot-Assisted Lung Brachytherapy, A. Trejos, A. Lin, S. Mohan, H. Bassan, C. Edirisinghe, R. Patel, C. Lewis, E. Yu, A. Fenster, R. Malthaner

Edward Yu

An integrated system for minimally invasive robot-assisted image-guided lung brachytherapy has been developed. The system incorporates an experimental setup for accurate radioactive seed placement with commercially available dosimetry planning software. The end result is a complete system that allows planning and executing a brachytherapy procedure with increased accuracy. The results of the in vitro seed placement evaluation show that seed misplacement has a significant effect on the volume receiving more than 200% of the dose (V200), and the minimum dosage received by 90% of the volume (D90).


Criteria On Utility Designing Of Convex Optimization In Fdma Networks, Zheng Sun, Wenjun Xu, Zhiqiang He, Kai Niu Apr 2008

Criteria On Utility Designing Of Convex Optimization In Fdma Networks, Zheng Sun, Wenjun Xu, Zhiqiang He, Kai Niu

Zheng Sun

In this paper, we investigate the network utility maximization problem in FDMA systems. We summarize with a suite of criteria on designing utility functions so as to achieve the global optimization convex. After proposing the general form of the utility functions, we present examples of commonly used utility function forms that are consistent with the criteria proposed in this paper, which include the well-known proportional fairness function and the sigmoidal-like functions. In the second part of this paper, we use numerical results to demonstrate a case study based on the criteria mentioned above, which deals with the subcarrier scheduling problem …


Coordinated Design Of Power System Stabilizers And Static Var Compensators In A Multimachine Power System Using Genetic Algorithms, Omar H. Abdalla, Wedad M. Refaey, Mohamed K. Saad, Gamal M. Sarhan Apr 2008

Coordinated Design Of Power System Stabilizers And Static Var Compensators In A Multimachine Power System Using Genetic Algorithms, Omar H. Abdalla, Wedad M. Refaey, Mohamed K. Saad, Gamal M. Sarhan

Omar H. Abdalla

This paper presents a procedure to coordinated design of PSSs and SVCs in a multimachine power system. The aims of the proposed method are to find the best location and the optimal parameters of these compensators in order to improve the steady state and transient performances and also to increase the system damping over a wide range of operating conditions. The objective function of the GA allows the selection of the PSSs and SVCs to shift critical closed loop eigenvalues to the left-hand side in the complex s-plane. The multimachine power system considered in this study consists of nine buses, …


Understanding The Role Of Noise In Stochastic Local Search: Analysis And Experiments, Ole J. Mengshoel Apr 2008

Understanding The Role Of Noise In Stochastic Local Search: Analysis And Experiments, Ole J. Mengshoel

Ole J Mengshoel

Stochastic local search (SLS) algorithms have recently been proven to be among the best approaches to solving computationally hard problems. SLS algorithms typically have a number of parameters, optimized empirically, that characterize and determine their performance. In this article, we focus on the noise parameter. The theoretical foundation of SLS, including an understanding of how to the optimal noise varies with problem difficulty, is lagging compared to the strong empirical results obtained using these algorithms. A purely empirical approach to understanding and optimizing SLS noise, as problem instances vary, can be very computationally intensive. To complement existing experimental results, we …


Cut Loss In Low-Voltage, Wideband Pin Attenuators, Chin-Leong Lim Mar 2008

Cut Loss In Low-Voltage, Wideband Pin Attenuators, Chin-Leong Lim

Chin-Leong Lim

Many RF applications, including Cable and Satellite TV (CATV / SATV) networks, rely on voltage-variable attenuators (VVAs) for gain adjustment. VVAs consisting of PIN diodes arranged as a PI network are popular in CATV / SATV service owing to their constant impedance, high linearity, multi-decade bandwidth, low part count and compactness. When fabricated from thick bulk PIN diodes for high linearity, the PI VVA configuration typically requires a 0-15V control range. But modern equipment typically operates at 5V or less. Capping the control voltage at 5V adversely raises the VVA's minimum attenuation. To enable low voltage operation without degrading the …


Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims Feb 2008

Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims

Dr. Et-touhami Es-sebbar

No abstract provided.