Engineering Commons^™

Utilization Of Automated Gcc Optimization For Dual-Width Instruction Sets On The Arm Architecture, Shane Watson

Computer Engineering

One of the most important considerations in embedded systems is code size. This consideration is obviously imposed by external factors such as cost and physical space, but what it boils down to is that we want our devices to be as powerful as they can within a (typically limited) specific form factor. This limits the amount of space we have for memory and as such we should always be considering the code size of our application and making sure it’s as efficient as possible. We also then need to consider other factors such as performance and power consumption. This is …

Experimental Evaluation Of Select Servers And Firewalls Under Denial Of Service Security Attacks, Raja Sekhar Reddy Gade

Theses and Dissertations - UTB/UTPA

Internet security requires newer prevention mechanisms to be implemented on web-servers and routers. Firewall/Intrusion Prevention mechanisms (IPS) can be deployed on host servers or routers as an added line of defense against Internet attacks. In this thesis, we evaluate performance of security mechanisms provided by these devices against Distributed Denial of Service (DDoS) attacks. The host based firewalls on Windows servers-2003 and 2008 were evaluated. In this thesis, we also evaluated Juniper Networks Netscreen-5GT firewall/IPS, and Cisco ASA-5510/IPS that are used in protecting web-servers against DDoS attacks. It was found that the host based firewalls and protection mechanisms on the …

Pulse Echo Ultrasonic Testing Of Adhesive Bonded Joints For Automotive Applications, Arun Ganapathi

All Theses

The growing prominence of adhesive bonding technology in automotive manufacture has necessitated the development of reliable and robust quality assurance techniques. Of the different Nondestructive testing technologies available, Ultrasonic testing has shown itself to be the most promising technique to satisfy the requirements in automobile production. The current work attempts to apply two variations of the Ultrasonic Pulse Echo technique namely Contact and Immersion testing for inspecting typical hem bonded automotive joints. The joints have been tested for disbond at the various metal-adhesive interfaces by using an ultrasonic scan comparison method which compares the acquired signals against a reference scan …

Normative Reflectance And Transmittance Measurements On Healthy Newborn And 1-Month-Old Infants, Gabrielle R. Merchant, Nicholas J. Horton, Susan E. Voss

Engineering: Faculty Publications

Objective:

Ear-canal-based wideband reflectance (WBR) measurements may provide objective measures to assess and monitor middle-ear status in young babies. This work presents WBR measurements of power reflectance and transmittance on populations of healthy newborn babies (3 to 5 days) and healthy 1-mo-old babies (28 to 34 days). Thus, this work determines how power reflectance and transmittance vary between newborn and 1-mo-old babies and characterizes the range of these measures in normal populations.

Design:

Power reflectance and transmittance were calculated from pressure measurements made in the ear canals of seven newborn (12 ears) and eleven 1-mo-old (19 ears) babies. Permutation tests, …

Barriers And Best Practices For Material Management In The Healthcare Sector, Carlos Callender, Scott Erwin Grasman

Engineering Management and Systems Engineering Faculty Research & Creative Works

The primary focus of the healthcare sector has been to provide patients with the best quality of care. Recently, the escalating cost of supplies and the severe competition among healthcare providers has significantly increased the pressure on material managers to operate more cost-efficiently without compromising high patient care standards. While other sectors have experienced success through the deployment of supply chain management practices, the healthcare sector has not seen major improvements in this area; however, in spite of the uniqueness and complexity of the healthcare supply chain, opportunities for improvements are plentiful. This article provides an assessment of material management …

A Reinforcement Learning Approach For Inventory Replenishment In Vendor-Managed Inventory Systems With Consignment Inventory, Zheng Sui, Abhijit Gosavi, Li Lin

Engineering Management and Systems Engineering Faculty Research & Creative Works

In a Vendor-Managed Inventory (VMI) system, the supplier makes decisions of inventory management for the retailer; the retailer is not responsible for placing orders. There is a dearth of optimization models for replenishment strategies for VMI systems, and the industry relies on well-understood, but simple models, e.g., the newsvendor rule. in this article, we propose a methodology based on reinforcement learning, which is rooted in the Bellman equation, to determine a replenishment policy in a VMI system with consignment inventory. We also propose rules based on the newsvendor rule. Our numerical results show that our approach can outperform the newsvendor. …

Robust Neural Network Rise Observer Based Fault Diagnostics And Prediction, James W. Fonda, S. (Sarangapani) Jagannathan, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

A novel fault diagnostics and prediction scheme in continuous time is introduced for a class of nonlinear systems. The proposed method uses a novel neural network (NN) based robust integral sign of the error (RISE) observer, or estimator, allowing for semi-global asymptotic stability in the presence of NN approximation errors, disturbances and unmodeled dynamics. This is in comparison to typical results presented in the literature that show only boundedness in the presence of uncertainties. The output of the observer/estimator is compared with that of the nonlinear system and a residual is used for declaring the presence of a fault when …

Equivalent Circuit Models For Evaluation Of Bandgap Limits For Planar Electromagnetic Bandgap Structures, Francesco De Paulis, Leo Raimondo, Antonio Orlandi, Liehui Ren, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In this work different physic based equivalent lumped element circuits models representing planar EBG structures are developed. their results, in terms of evaluation of the lower and upper limits of the bandgap, are compared with a three-dimensional simulation considered as reference. Guidelines for the use of these models for their use in planar EBG design are developed. ©2010 IEEE.

Extracting Physical Ic Models Using Near-Field Scanning, Zhenwei Yu, Jayong Koo, Jason A. Mix, Kevin Slattery, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Accurate modeling of chip and chip-package is critical for EMI (Electromagnetic Interference) and RFI (RF Interference) analysis and prediction. in this paper, a model based on an array of dipoles from near-field measurement is proposed. a simple active circuit is simulated in a 3-D full-wave simulation tool, and the dipole model is calculated from the near-field data in the simulation using inverse method with regularization technique. This model has clear physical meaning, and it is validated using field at another place. ©2010 IEEE.

Improved Target Impedance And Ic Transient Current Measurement For Power Distribution Network Design, Jingook Kim, Songping Wu, Hanfeng Wang, Yuzou Takita, Hayato Takeuchi, Kenji Araki, Gang Feng, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

An improved definition of target impedance is proposed in this paper, which is derived from the time-domain waveforms of the IC transient current and the allowable voltage fluctuation. the proposed target impedance removes the unnecessary constraint in the original definition and allows for more cost-effective power distribution network (PDN) designs for consumer electronic products. a measurement procedure to obtain IC transient current waveforms is also developed for the PDN designs utilizing power traces. the proposed target impedance and the measurement procedure have been validated using practical functioning designs. ©2010 IEEE.

Review Of Multi-Scale Electromagnetic Modeling, W. C. Chew, Lijun Jiang, H. Y. Chao, A. J. Hesford, M. K. Li, Z. G. Qian, Y. G. Liu, Y. P. Chen, Z. H. Ma, L. E. Sun, M. S. Tong, C. Davis, W. E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

This paper reviews various methods to solve multiscale problems ranging from low-frequency methods to very high-frequency methods. ©2010 IEEE.

Augmented Epa With Augmented Efie Method For Packaging Analysis, Zuhui Ma, Lijun Jiang, Wengcho Chew, Maokun Li, Zhiguo Qian

Electrical and Computer Engineering Faculty Research & Creative Works

It is evident that the low frequency full wave electromagnetic modelling is necessary for IC packaging analysis. Considering the complexity, it is very difficult to solve the whole problem directly. Even though the domain decomposition method is a legitimate approach for these types of problems, the domain decomposition method based on the equivalence principle has the low frequency breakdown issue. In this paper, we developed a low frequency augmented equivalence principle algorithm (AEPA) with the augmented electric field integral equation (AEFIE) for packaging and IC analysis. On the equivalence surfaces, not only the electric current and the magnetic current, but …

Statistical Channel Modeling Of Wireless Shallow Water Acoustic Communications From Experiment Data, Jian Zhang, Jesse Cross, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper analyzes statistical characteristics of underwater acoustic channels estimated by ocean experimental data. the baseband complex channel impulse responses (CIRs) are estimated by a time-domain least square method with sliding windows applied to long probing sequences. the probability density functions (PDF) of the real part, imaginary part, magnitude, and phase of the CIR are evaluated, and the two sample Kolmogorov-Smirnov test is used to measure fitness of the magnitude PDF to the Gamma, Rayleigh, and compound-K distributions. the second-order statistics of the channel are also investigated in terms of autocorrelation function, channel coherence time, and scattering function. the experimental …

A Mean-Variance Optimization Algorithm, Istvan Erlich, Ganesh K. Venayagamoorthy, Nakawiro Worawat

Electrical and Computer Engineering Faculty Research & Creative Works

A new stochastic optimization algorithm referred to by the authors as the 'Mean-Variance Optimization' (MVO) algorithm is presented in this paper. MVO falls into the category of the so-called "population-Based stochastic optimization technique." the uniqueness of the MVO algorithm is based on the strategic transformation used for mutating the offspring based on mean-variance of the n-best dynamic population. the mapping function used transforms the uniformly distributed random variation into a new one characterized by the variance and mean of the n-best population attained so far. the searching space within the algorithm is restricted to the range - zero to one …

Applying Feature Selective Validation (Fsv) As An Objective Function For Data Optimization, Siming Pan, Hanfeng Wang, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Feature Select Validation (FSV) is a widely used validation method for data comparison. FSV provides a quantitative standard to describe the similarity between two sets of data. in this paper, the application of the FSV technique is extended to data optimization. the raw data obtained from simulations or measurements are often non-ideal for further processing. Several techniques, such as data perturbation, can be used to improve the data quality in certain aspects. However, after modifications the new data could be very different to the original one. using FSV as an objective function for the optimization process is discussed in this …

Analyzing Via Impedance Variations With A Stochastic Collation Method, Jianxiang Shen, Hanfeng Wang, Ji Chen, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we describe a systematic approach to optimize and analyze the equivalent characteristic impedance of practical via structures. the procedure consists of (a) optimizing via structures for impedance matching using a Genetic algorithm, and (b) numerically characterize, by stochastic collocation method, the sensitivity of the equivalent characteristic impedance to the manufacturing uncertainties in the various geometrical parameters of a via structure. Such procedure naturally leads to a rigorous methodology for EM design/control in the presence of multiple sources of uncertainty. ©2010 IEEE.

Efficient Mid-Frequency Plane Inductance Computation, Fan Zhou, Albert E. Ruehli, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In power distribution networks (PDN), the modelling of the mid-frequency inductance for Zpp type plane pairs is very important. It is a key step for the placement of the decoupling capacitors. This paper gives an efficient approach for the calculation of the inductance for different capacitor placements. the PEEC based formulations takes advantage of the opposite currents in the planes. This leads to compute time reductions and memory savings for both the element calculation and the matrix solve step. We also use a formulation where placement of capacitors leads to only small changes in the circuit matrix. Comparisons with other …

Recent Development Of Via Models: Hybrid Circuit And Field Analysis, Yaojiang Zhang, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Via-plate interaction can be modeled as lumped circuits for vias and a two-dimensional field problem for the plate domain. the accuracy of the improved intrinsic via model and the conventional physics-Based via model is investigated by comparing them with either analytical formula or numerical simulations for a via in a circular plate pair with various edge boundary conditions. It is found that the intrinsic via model matches very well with both the analytical formula and numerical solutions in all the examples studied. However, the physics-Based via model is only an acceptable approximation at low frequencies and its accuracy is not …

Modeling Of A Gyro-Stabilized Helicopter Camera System Using Neural Networks, Nicholas Joseph Layshot

Master's Theses

On-board gimbal systems for camera stabilization in helicopters are typically based on linear models. Such models, however, are inaccurate due to system nonlinearities and complexities. As an alternative approach, artificial neural networks can provide a more accurate model of the gimbal system based on their non-linear mapping and generalization capabilities.

This thesis investigates the applications of artificial neural networks to model the inertial characteristics (on the azimuth axis) of the inner gimbal in a gyro-stabilized multi-gimbal system. The neural network is trained with time-domain data obtained from gyro rate sensors of an actual camera system. The network performance is evaluated …

An Investigation Of Initially Delaminated Composite Sandwich With Delamination Arrest Mechanism Under Buckling Loading, Tony D. Tran

Master's Theses

This thesis involves the development of a fiberglass-foam composite sandwich structure with the introduction of delamination arrestment keys; therefore, a study of an initially delaminated composite sandwich structure was the experimental analysis on multiple configurations in how the arrestment keys are placed.

The first part of this thesis research was to the experimental design and manufacturing of the composite sandwich plates. These plates were later cut down to the specific test dimensions and manufacturing processes for the composite sandwich plates and test specimens were created. The composite sandwich plates were manufactured using a vacuum resin infusion process. The dimensions of …

Correcting Liquefaction Resistance Of Partially Saturated Soil Using Compression Wave Velocity, Md Hossain

All Theses

Empirical relationships for correcting liquefaction resistance of partially saturated soil using longitudinal (P-) wave velocity (V_P) and shear (S-) wave velocity (V_S) are developed and evaluated in this thesis. The relationships are based on the laboratory test results for four different types of sands and one silt published by other investigators. The data used to develop the relationship with V_P exhibit less scatter than the data used to develop the relationship with V_P/V_S. For this reason, the V_P based relationship is recommended for correcting liquefaction resistance of partially saturated soil. …

Toward Automated Detection And Diagnosis Of Mammographic Microcalcifications, Imad Mohammad Zyout

Dissertations

Mammographie diagnosis is the most effective technique to detect breast cancer in its infancy when it is most responsive to treatment. An early and a significant indicator of breast cancer is the presence of clustered microcalcifications (MCs). Mammographie MCs greatly vary in their appearance and shape, and become indistinguishable when surrounded by dense breast tissue. This makes radiologist's interpretation of mammograms a tedious and an error prone task.

Although computer aided diagnosis (CAD) methods are being developed to aid radiologist in detecting and analyzing the malignancy of MCs, existing systems have not achieved a satisfactory performance. The specificity of existing …

Using Knowledge Building To Support Deep Learning, Collaboration And Innovation In Engineering Education, Glenn W. Ellis, Alan N. Rudnitsky, Mary A. Moriarty

Engineering: Faculty Publications

Knowledge building is a potentially transformative approach to engineering education. In knowledge building students participate in an interactive discourse in which they work together to broaden ideas, reform problems and share knowledge - the result being a deeper level of understanding and the collaborative production of new knowledge. In 2009 we conducted a knowledge building pilot study in the Picker Engineering Program at Smith College. In this study students worked together to formulate a question about the potential for a conscious machine and then engaged in an intensive knowledge building discourse. Assessment data showing the effectiveness of the approach and …

Campus Assessment Of Building Heating Energy Consumption-Informing The Climate Action Plan, E. Grover-Silva, D. A. Mckahn, D. Weisbord

Engineering: Faculty Publications

We present a methodology to assess the technical feasibility of building thermal energy reduction strategies from an architecturally diverse building stock that is not metered. While carbon emissions forecasting efforts are typically the domain of planning and policy, the process detailed here can inform institutional decision-making relative to investments in renewable energy, infrastructure, and offsets to further reduce carbon footprint. As a case study, we estimated the Smith College campus building thermal energy losses, an analysis which informed our Sustainability and Climate Action Plan [1]. Due to building specific physical constraints and planned renovations, different thermal envelope improvement scenarios were …

Characterization Of Anti-Proteolytic And Anti-Proliferative Activities Of Pentagalloylglucose; Its Potential Application As A Therapeutic Agent In Vascular Diseases, Chaitra Cheluvaraju

All Dissertations

Cardiovascular diseases are the leading causes of mortality in the United States and will cost around $500 billion this year alone. Elevated proteolytic activity, increased proliferation and migration of vascular smooth muscle cells are hallmarks of atherosclerosis, stenosis and aortic aneurysms. These diseases often manifest the transdifferentiation of vascular smooth muscle cells into osteoblast-like cells followed by deposition of hydroxyapatite–like mineral in the arterial walls.
Currently, there are no standard treatments available for vascular calcification or aneurysms. Atherosclerosis treatment options are limited to statins while balloon angioplasty and stenting – surgical procedures for stenosis, often end in restenosis. Therefore, we …

Characterization Of Acetogenic And Methanogenic Leachates Generated From A Sanitary Landfill Site, Aik Heng Lee, Hamid Nikraz, Yung Tse Hung

Civil and Environmental Engineering Faculty Publications

Decomposition processes take place in landfill generate leachates that can be categorized mainly of acetogenic and methanogenic in nature. BOD:COD ratio computed in this study for a landfill site over a 3 years duration revealed as a good indicator to identify acetogenic leachate from methanogenic leachate. Correlation relationships to predict pollutant level taking into consideration of climatic condition are derived.

The Effectiveness Of Silica Sand In Semi-Aerobic Stabilized Landfill Leachate Treatment, Ezlina Othman, Mohd Suffian Yusoff, Hamidi Abdul Aziz, Mohd Nordin Adlan, Mohammed J.K. Bashir, Yung Tse Hung

Civil and Environmental Engineering Faculty Publications

© 2010 by the authors. This study examines the suitability of natural silica sand as a low-cost adsorbent for the removal of ammoniacal nitrogen and heavy metals, particularly iron and zinc, from semi-aerobic stabilized landfill leachate. Leachate samples were collected from the Pulau Burung landfill site (PBLS) in Penang, Malaysia. The above-mentioned contaminants are highlighted in this study because of their unsafe concentrations at PBLS. The effects of shaking time, settling time, and silica sand dosage on the study parameter removal efficiencies were investigated to predict the performance of the process. The adsorptions of ammoniacal nitrogen, iron, and zinc were …

Singular Value Decomposition Metrics Show Limitations Of Detector Design In Diffuse Fluorescence Tomography, Frederic Leblond, Kenneth M. Tichauer, Brian W. Pogue

Dartmouth Scholarship

The spatial resolution and recovered contrast of images reconstructed from diffuse fluorescence tomography data are limited by the high scattering properties of light propagation in biological tissue. As a result, the image reconstruction process can be exceedingly vulnerable to inaccurate prior knowledge of tissue optical properties and stochastic noise. In light of these limitations, the optimal source-detector geometry for a fluorescence tomography system is non-trivial, requiring analytical methods to guide design. Analysis of the singular value decomposition of the matrix to be inverted for image reconstruction is one potential approach, providing key quantitative metrics, such as singular image mode spatial …

Bi-Material Attachment Through A Soft Tissue Interfacial System, Y. X. Liu, S. Thomopoulos, Victor Birman, J. S. Li, G. M. Genin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

The Cd-Te Phase Diagram, Robert F. Brebrick

Mechanical Engineering Faculty Research and Publications

The properties of the liquid phase in the Cd–Te system are fit using thermodynamic properties of CdTe(c) recently optimized by the author. These include a high temperature heat capacity significantly lower than commonly used such that the enthalpy of formation of CdTe(c) at its melting point is about 10 kJ/mol less negative than previously thought. An associated solution model with Cd, CdTe, and Te species is used. Seven adjustable parameters are sufficient to quantitatively fit the liquidus and partial pressures of Te₂ and Cd. Additional partial pressures for Te rich CdTe(c) near its melting point are extracted from an …