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Old Dominion University

2017

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Full-Text Articles in Engineering

Illuminator, Volume 1, Issue 3, Batten College Of Engineering & Technology Dec 2017

Illuminator, Volume 1, Issue 3, Batten College Of Engineering & Technology

College of Engineering & Technology Newsletter

December 2017 issue of Illuminator, a monthly publication of ODU's Batten College of Engineering and Technology.


Illuminator, Volume 1, Issue 2, Batten College Of Engineering & Technology Nov 2017

Illuminator, Volume 1, Issue 2, Batten College Of Engineering & Technology

College of Engineering & Technology Newsletter

November 2017 issue of Illuminator, a monthly publication of ODU's Batten College of Engineering and Technology.


Effects Of Vacuuming Pervious Concrete On Infiltration Rate, Demetrios E. Maurakis, Eugene G. Maurakis Oct 2017

Effects Of Vacuuming Pervious Concrete On Infiltration Rate, Demetrios E. Maurakis, Eugene G. Maurakis

Virginia Journal of Science

The objectives of this research were twofold: test the infiltration rate of pervious concrete before and after vacuum cleaning, and assess infiltration variability over time. Infiltration tests were performed on a 558.2 m2 area of pervious concrete, divided into sixteen 0.35 m2 test areas in a parking area at the Science Museum of Virginia in Richmond, Virginia on five dates from November 4-December 30, 2013. Average infiltration rates (avg.= 22.8 and 36.3 L/m2/min) immediately after vacuuming were lower than those (avg.=30.7 and 41.3 L/m2/min) before vacuuming. We hypothesize that the vacuuming lifted materials towards the surface …


Illuminator, Volume 1, Issue 1, Batten College Of Engineering & Technology Oct 2017

Illuminator, Volume 1, Issue 1, Batten College Of Engineering & Technology

College of Engineering & Technology Newsletter

October 2017 issue of Illuminator, a monthly publication of ODU's Batten College of Engineering and Technology.


A Picture Is Worth A Thousand Roads, Keith Pierce Oct 2017

A Picture Is Worth A Thousand Roads, Keith Pierce

News Items

No abstract provided.


Activation Of The Phospholipid Scramblase Tmem16f By Nanosecond Pulsed Electric Field (Nspef) Facilitates Its Diverse Cytophysiological Effects, Claudia Muratori, Andrei G. Pakhomov, Elena Gianulis, Jade Meads, Maura Casciola, Peter A. Mollica, Olga N. Pakhomova Oct 2017

Activation Of The Phospholipid Scramblase Tmem16f By Nanosecond Pulsed Electric Field (Nspef) Facilitates Its Diverse Cytophysiological Effects, Claudia Muratori, Andrei G. Pakhomov, Elena Gianulis, Jade Meads, Maura Casciola, Peter A. Mollica, Olga N. Pakhomova

Bioelectrics Publications

Nanosecond pulsed electric fields (nsPEF) are emerging as a novel modality for cell stimulation and tissue ablation. However, the downstream protein effectors responsible for nsPEF bioeffects remain to be established. Here we demonstrate that nsPEF activate TMEM16F (or Anoctamin 6), a protein functioning as a Ca2+-dependent phospholipid scramblase and Ca2+-activated chloride channel. Using confocal microscopy and patch clamp recordings, we investigated the relevance of TMEM16F activation for several bioeffects triggered by nsPEF, including phosphatidylserine (PS) externalization, nanopore-conducted currents, membrane blebbing, and cell death. In HEK 293 cells treated with a single 300-ns pulse of 25.5 kV/cm, …


Study Of Modified Deposition Process For Cu(In,Ga)Se2 Solar Cell Back Contact, Tasnuva Ashrafee Oct 2017

Study Of Modified Deposition Process For Cu(In,Ga)Se2 Solar Cell Back Contact, Tasnuva Ashrafee

Electrical & Computer Engineering Theses & Dissertations

As the worldwide demand for renewable energy is increasing, growth of the global share of alternative energy sources would improve overall energy security as well as bring environmental benefits. So far, solar cells - the devices that convert direct sunlight into electricity - are dominated by silicon devices. Another alternative is thin film solar cell, whose main inspiration is to reduce the electricity production cost. Cu(In, Ga)Se2 (CIGS) solar cells are considered to have a great prospective because of reduced material and energy consumption during manufacturing. Many CIGS solar cell manufacturers are already exhibiting GW-scale production capacity. With the …


Implementation Of A Multi-Criteria Decision Analysis (Mcda) Toolkit To Aid In Ranking Naval Mission Vessel Combinations With Uncertainty, Andrew R. Miller Oct 2017

Implementation Of A Multi-Criteria Decision Analysis (Mcda) Toolkit To Aid In Ranking Naval Mission Vessel Combinations With Uncertainty, Andrew R. Miller

Engineering Management & Systems Engineering Theses & Dissertations

United States (U.S.) military bases have largely been constructed outside of the contiguous United States (OCONUS) due to the need of close support logistics for conflicts and wars. In contrast, military bases within the contiguous United States (CONUS) have been constructed mostly due to economic and other related monetary factors. In addition to monetary concerns for the placement of military bases (specifically naval bases), there exists tactical, environmental, cultural, climate, logistical, and geographical issues that need to be fully considered before deciding on a naval installation location and the vessels to be stationed there. I will present a new toolkit …


Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen Oct 2017

Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen

Civil & Environmental Engineering Theses & Dissertations

Water pollution is an ongoing problem that can be attributed to human activities. As world population increases and countries become more developed, this problem intensifies. Fortunately, the causes and solutions of water pollution are documented and have been implemented with various levels of success. These solutions, or Best Management Practices (BMPs), vary in type and function and remove pollutants from runoff prior to it reaching rivers, lakes, and other bodies of water. This study investigates bioretention basins, a specific group of BMPs, and presents analysis and prediction of their performance, of which our knowledge is incomplete in the existing literature. …


A Correlational Study Of Sansec Sensors’ Electric Field Distribution On Lightning Attachment, Kayla M. Farrow Oct 2017

A Correlational Study Of Sansec Sensors’ Electric Field Distribution On Lightning Attachment, Kayla M. Farrow

Electrical & Computer Engineering Theses & Dissertations

Old Dominion University and the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) Aviation Safety Program Atmospheric Environmental Safety Technologies Project team conducted research in using SansEC (Sans Electric Connection) sensors to provide lightning strike protection (LSP) and damage mitigation for composite aircraft. SansEC sensors are simplistic devices consisting of an open circuit conductive trace, shaped in a planar geometric spiral [1], [2], [3]. SansEC sensors can be designed in various shapes and sizes depending on the application. For applications on exterior aircraft surfaces, the sensor must be designed to perform the required lightning strike protection [1], [3]. …


Emergency Diesel-Electric Generator Set Maintenance And Test Periodicity, Stephen John Fehr Oct 2017

Emergency Diesel-Electric Generator Set Maintenance And Test Periodicity, Stephen John Fehr

Engineering Management & Systems Engineering Theses & Dissertations

Manufacturer and industry recommendations vary considerably for maintenance and tests of emergency diesel-electric generator sets in emergency standby duty. There is little consistency among generator sets of similar technology, and manufacturers and their representatives often provide contradictory guidance. As a result, periodicity of emergency diesel-electric generator set maintenance and tests varies considerably in practice. Utilizing the framework proposed and tested by Fehr (2014), this research developed a parametric regression survival model of the reliability of modern diesel-electric generator sets in emergency standby duty as a function of maintenance, age, and cumulative run hours. A survival regression technique leveraging Cox’s (1972) …


Vulnerability Assessment Of Critical Bridges In The Hampton Roads Region Of Virginia To Storm Surge Flooding Under Sea Level Rise, Luca Castrucci Oct 2017

Vulnerability Assessment Of Critical Bridges In The Hampton Roads Region Of Virginia To Storm Surge Flooding Under Sea Level Rise, Luca Castrucci

Civil & Environmental Engineering Theses & Dissertations

In this thesis, a hydrodynamic model was developed to study the vulnerability of the transportation infrastructure in the Hampton Roads region of Virginia to storm surge flooding under sea level rise. The Hampton Roads region is the second most affected area by relative sea level rise in the United States. The hydrodynamic model was validated for tide prediction, and its performance in storm surge simulation was validated with data from Hurricane Irene (2011). The developed model was then applied to eight flood-prone bridges in the transportation network that connect the cities of Norfolk, Hampton, Virginia Beach, Chesapeake and Portsmouth; the …


Development Of A Data Acquisition System For Unmanned Aerial Vehicle (Uav) System Identification, Donald Joseph Lear Oct 2017

Development Of A Data Acquisition System For Unmanned Aerial Vehicle (Uav) System Identification, Donald Joseph Lear

Mechanical & Aerospace Engineering Theses & Dissertations

Aircraft system identification techniques are developed for fixed wing Unmanned Aerial Vehicles (UAV). The use of a designed flight experiment with measured system inputs/outputs can be used to derive aircraft stability derivatives. This project set out to develop a methodology to support an experiment to model pitch damping in the longitudinal short-period mode of a UAV. A Central Composite Response Surface Design was formed using angle of attack and power levels as factors to test for the pitching moment coefficient response induced by a multistep pitching maneuver.

Selecting a high-quality data acquisition platform was critical to the success of the …


Thermally Assisted Pulsed Electric Field Ablation For Cancer Therapy, James Michael Hornef Oct 2017

Thermally Assisted Pulsed Electric Field Ablation For Cancer Therapy, James Michael Hornef

Biomedical Engineering Theses & Dissertations

Pulsed Electric Fields (PEF) have promised improved treatment results in a variety of cancer types including melanoma, pancreatic and lung squamous cancer. Recent studies show that PEF-based cancer therapy may be improved further with the assistance of moderate heating of the target. Experiments were performed to design, calibrate and implement a feedback-looped infrared laser irradiation system that could maintain specified temperatures during the treatment. The exact treatment area, penetration depth and thermal distribution of a 980-nm laser fiber were quantified using several methods, including the knife-edge technique and a tissue optical property study. In vivo and in vitro experiments using …


Using Optimality Theory And Reference Points To Improve The Diversity And Convergence Of A Fuzzy-Adaptive Multi-Objective Particle Swarm Optimizer, Amit A. Kulkarni Oct 2017

Using Optimality Theory And Reference Points To Improve The Diversity And Convergence Of A Fuzzy-Adaptive Multi-Objective Particle Swarm Optimizer, Amit A. Kulkarni

Mechanical & Aerospace Engineering Theses & Dissertations

Particle Swarm Optimization (PSO) has received increasing attention from the evolutionary optimization research community in the last twenty years. PSO is a metaheuristic approach based on collective intelligence obtained by emulating the swarming behavior of bees. A number of multi-objective variants of the original PSO algorithm that extend its applicability to optimization problems with conflicting objectives have also been developed; these multi-objective PSO (MOPSO) algorithms demonstrate comparable performance to other state-of-the-art metaheuristics. The existence of multiple optimal solutions (Pareto-optimal set) in optimization problems with conflicting objectives is not the only challenge posed to an optimizer, as the latter needs to …


Development And Validation Of A Hybrid Virtual/Physical Nuss Procedure Surgical Trainer, Mohammad F. Obeid Oct 2017

Development And Validation Of A Hybrid Virtual/Physical Nuss Procedure Surgical Trainer, Mohammad F. Obeid

Computational Modeling & Simulation Engineering Theses & Dissertations

With continuous advancements and adoption of minimally invasive surgery, proficiency with nontrivial surgical skills involved is becoming a greater concern. Consequently, the use of surgical simulation has been increasingly embraced by many for training and skill transfer purposes. Some systems utilize haptic feedback within a high-fidelity anatomically-correct virtual environment whereas others use manikins, synthetic components, or box trainers to mimic primary components of a corresponding procedure.

Surgical simulation development for some minimally invasive procedures is still, however, suboptimal or otherwise embryonic. This is true for the Nuss procedure, which is a minimally invasive surgery for correcting pectus excavatum (PE) – …


Enhancement Of Thermoelectric Properties Of Ald Synthesized Pbte And Pbse By Phonon Engineering, Xin Chen Oct 2017

Enhancement Of Thermoelectric Properties Of Ald Synthesized Pbte And Pbse By Phonon Engineering, Xin Chen

Electrical & Computer Engineering Theses & Dissertations

Thermoelectrics is a green renewable energy technology that plays an important role in power generation due to its potential in generating electricity out of waste heat. The main challenge for the development of thermoelectrics is its low conversion efficiency. One key strategy to improve conversion efficiency is focused on reducing the thermal conductivity of thermoelectric materials. In this thesis, the novel phononic engineering concept was implemented by conformal ALD deposition of PbTe, PbSe thermoelectric films, and PbTe/PbSe nanolaminates on patterned silicon substrates in order to improve the thermoelectric performance of the thermoelectric films. The silicon substrates were lithographically patterned with …


Diffusion Modeling Of Impurities Through The Molybdenum Back Contact Of Cigs Solar Cells, Chinedum John Akwari Oct 2017

Diffusion Modeling Of Impurities Through The Molybdenum Back Contact Of Cigs Solar Cells, Chinedum John Akwari

Electrical & Computer Engineering Theses & Dissertations

CIGS is a major technology in photovoltaics and depends heavily, as any other PV technology, on the capacity to achieve the highest efficiency possible to compete on the market. Alkaline elements, notably sodium and potassium, play a key role in this matter as they enhance the open circuit voltage and the fill factor of the CIGS solar cells. However, this effect exists only for very specific concentration of sodium and potassium. These impurities typically diffuse through the soda-lime glass substrate.

Via modeling of the SIMS data, we try to understand and predict the diffusion mechanisms of these impurities from the …


Methodology To Perform Cyber Lethality Assessment, Matthew W. Zurasky Oct 2017

Methodology To Perform Cyber Lethality Assessment, Matthew W. Zurasky

Engineering Management & Systems Engineering Theses & Dissertations

The Naval Surface Warfare Center, Dahlgren Division (NSWCDD) Lethality and Effectiveness Branch is the Navy’s subject matter experts (SME) on target vulnerability, weapon lethality, and weapon effectiveness. Branch personnel currently exercise expertise in the kinetic and directed energy weapon domains. When the Navy develops weapons in the kinetic and directed energy domains, there are clear and well established procedures and methodologies for performing target characterization that support weapon-target pairing. Algorithms exist to describe the likelihood of damage effects. It is natural that in the paradigm shift to cyberspace warfare that the Branch provide these same services to the warfighter in …


Modeling Energy Consumption Of High-Performance Applications On Heterogeneous Computing Platforms, Gary D. Lawson Jr. Oct 2017

Modeling Energy Consumption Of High-Performance Applications On Heterogeneous Computing Platforms, Gary D. Lawson Jr.

Computational Modeling & Simulation Engineering Theses & Dissertations

Achieving Exascale computing is one of the current leading challenges in High Performance Computing (HPC). Obtaining this next level of performance will allow more complex simulations to be run on larger datasets and offer researchers better tools for data processing and analysis. In the dawn of Big Data, the need for supercomputers will only increase. However, these systems are costly to maintain because power is expensive. Thus, a better understanding of power and energy consumption is required such that future hardware can benefit.

Available power models accurately capture the relationship to the number of cores and clock-rate, however the relationship …


Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri Oct 2017

Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri

Civil & Environmental Engineering Theses & Dissertations

In recent years, the demand for renewable energy, mainly biomass has increased. The U.S. Energy Information Administration reported that more than 13.3% of the total energy production in the first seven months of 2017 was produced from a biomass source. Among all biomass resources, microalgae has brought a lot of attention due to their numerous advantages such as higher growth rate and productivity compared with the conventional energy crops, higher energy conversion efficiency by photosynthesis, and less water requirement than terrestrial crops. However, its development is far behind industrial production. Several research efforts across the globe have been concerned with …


Computational Modeling For Abnormal Brain Tissue Segmentation, Brain Tumor Tracking, And Grading, Syed Mohammad Shamin Reza Oct 2017

Computational Modeling For Abnormal Brain Tissue Segmentation, Brain Tumor Tracking, And Grading, Syed Mohammad Shamin Reza

Electrical & Computer Engineering Theses & Dissertations

This dissertation proposes novel texture feature-based computational models for quantitative analysis of abnormal tissues in two neurological disorders: brain tumor and stroke. Brain tumors are the cells with uncontrolled growth in the brain tissues and one of the major causes of death due to cancer. On the other hand, brain strokes occur due to the sudden interruption of the blood supply which damages the normal brain tissues and frequently causes death or persistent disability. Clinical management of these brain tumors and stroke lesions critically depends on robust quantitative analysis using different imaging modalities including Magnetic Resonance (MR) and Digital Pathology …


Computational Methods For Nonlinear Systems Analysis With Applications In Mathematics And Engineering, Geoffrey Kenneth Rose Oct 2017

Computational Methods For Nonlinear Systems Analysis With Applications In Mathematics And Engineering, Geoffrey Kenneth Rose

Mechanical & Aerospace Engineering Theses & Dissertations

An investigation into current methods and new approaches for solving systems of nonlinear equations was performed. Nontraditional methods for implementing arc-length type solvers were developed in search of a more robust capability for solving general systems of nonlinear algebraic equations. Processes for construction of parameterized curves representing the many possible solutions to systems of equations versus finding single or point solutions were established. A procedure based on these methods was then developed to identify static equilibrium states for solutions to multi-body-dynamic systems. This methodology provided for a pictorial of the overall solution to a given system, which demonstrated the possibility …


Delayed Hypersensitivity To Nanosecond Pulsed Electric Field In Electroporated Cells, Sarah D. Jensen, Vera A. Khorokhorina, Claudia Muratori, Andrei G. Pakhomov, Olga N. Pakhomova Sep 2017

Delayed Hypersensitivity To Nanosecond Pulsed Electric Field In Electroporated Cells, Sarah D. Jensen, Vera A. Khorokhorina, Claudia Muratori, Andrei G. Pakhomov, Olga N. Pakhomova

Bioelectrics Publications

We demonstrate that conditioning of mammalian cells by electroporation with nanosecond pulsed electric field (nsPEF) facilitates their response to the next nsPEF treatment. The experiments were designed to unambiguously separate the electroporation-induced sensitization and desensitization effects. Electroporation was achieved by bursts of 300-ns, 9 kV/cm pulses (50 Hz, n = 3–100) and quantified by propidium dye uptake within 11 min after the nsPEF exposure. We observed either sensitization to nsPEF or no change (when the conditioning was either too weak or too intense, or when the wait time after conditioning was too short). Within studied limits, conditioning never caused desensitization. …


A Systems-Based Framework For Design And Analysis Of An R And D Structure, Polinpapilinho F. Katina, Charles B. Keating, Luna M. Magpili Sep 2017

A Systems-Based Framework For Design And Analysis Of An R And D Structure, Polinpapilinho F. Katina, Charles B. Keating, Luna M. Magpili

Engineering Management & Systems Engineering Faculty Publications

A critical challenge for managerial effectiveness and competitive advantage in research and development (R and D) organizations is developing an appropriate structural configuration. However, in finding an appropriate structural configuration, R and D managers are faced with unprecedented levels of uncertainty, ambiguity, and accelerating complexity, coupled with demands for increased productivity. This paper develops a systems-based framework to support rigorous design, analysis, and transformation of the structure for R and D organizations. The framework development includes: (1) a review of the literature for the nature and role of the structure in R and D management; (2) setting of the R …


Damage-Free Peripheral Nerve Stimulation By 12-Ns Pulsed Electric Field, Maura Casciola, Shu Xiao, Andrei G. Pakhomov Sep 2017

Damage-Free Peripheral Nerve Stimulation By 12-Ns Pulsed Electric Field, Maura Casciola, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Modern technologies enable deep tissue focusing of nanosecond pulsed electric field (nsPEF) for non-invasive nerve and muscle stimulation. However, it is not known if PEF orders of magnitude shorter than the activation time of voltage-gated sodium channels (VGSC) would evoke action potentials (APs). One plausible scenario requires the loss of membrane integrity (electroporation) and resulting depolarization as an intermediate step. We report, for the first time, that the excitation of a peripheral nerve can be accomplished by 12-ns PEF without electroporation. 12-ns stimuli at 4.1-11 kV (3.3-8.8 kV/cm) evoked APs similarly to conventional stimuli (100-250 mus, 1-5 V, 103-515 V/m), …


Controllable Moderate Heating Enhances The Therapeutic Efficacy Of Irreversible Electroporation For Pancreatic Cancer, Chelsea M. Edelblute, James Hornef, Niculina I. Burcus, Thomas Norman, Stephen J. Beebe, Karl Schoenbach, Richard Heller, Chunqi Jiang, Sigi Guo Sep 2017

Controllable Moderate Heating Enhances The Therapeutic Efficacy Of Irreversible Electroporation For Pancreatic Cancer, Chelsea M. Edelblute, James Hornef, Niculina I. Burcus, Thomas Norman, Stephen J. Beebe, Karl Schoenbach, Richard Heller, Chunqi Jiang, Sigi Guo

Bioelectrics Publications

Irreversible electroporation (IRE) as a non-thermal tumor ablation technology has been studied for the treatment of pancreatic carcinoma and has shown a significant survival benefit. We discovered that moderate heating (MH) at 43°C for 1-2 minutes significantly enhanced ex vivo IRE tumor ablation of Pan02 cells by 5.67-fold at 750 V/cm and by 1.67-fold at 1500 V/cm. This amount of heating alone did not cause cell death. An integrated IRE system with controllable laser heating and tumor impedance monitoring was developed to treat mouse ectopic pancreatic cancer. With this novel IRE system, we were able to heat and maintain the …


Optimal Control-Based Inverse Determination Of Electrode Distribution For Electroosmotic Micromixer, Yuan Li, Yongbo Deng, Zhenyu Liu, Teng Zhou, Yihui Wu, Shizhi Qian Aug 2017

Optimal Control-Based Inverse Determination Of Electrode Distribution For Electroosmotic Micromixer, Yuan Li, Yongbo Deng, Zhenyu Liu, Teng Zhou, Yihui Wu, Shizhi Qian

Mechanical & Aerospace Engineering Faculty Publications

This paper presents an optimal control-based inverse method used to determine the distribution of the electrodes for the electroosmotic micromixers with external driven flow from the inlet. Based on the optimal control method, one Dirichlet boundary control problem is constructed to inversely find the optimal distribution of the electrodes on the sidewalls of electroosmotic micromixers and achieve the acceptable mixing performance. After solving the boundary control problem, results are also provided to demonstrate the effectiveness of the proposed method; the step-shaped distribution of the external electric potential imposed on the sidewalls is obtained, and the electrodes with an interlaced arrangement …


The Effect Of Magnification Loupes On Dental Hygienists' Posture While Exploring, Emily Ludwig, Gayle B. Mccombs, Susan L. Tolle, Daniel M. Russell Aug 2017

The Effect Of Magnification Loupes On Dental Hygienists' Posture While Exploring, Emily Ludwig, Gayle B. Mccombs, Susan L. Tolle, Daniel M. Russell

Dental Hygiene Faculty Publications

Purpose: The purpose of this study was to determine the effects of dental magnification loupes on posture during instrumentation.

Methods: A convenience sample of 27 right-handed dental hygienists, with no prior history of injuries or disabilities of the head, neck, or trunk region, enrolled in the study. Baseline posture calibration was taken and tri-axial accelerometers were placed on four locations of the head and trunk (occipital region of head; cervical vertebrae C5; thoracic vertebrae T5; lumbar vertebrae L1) to measure acceleration and the orientation of the body to gravity. Participants were randomly assigned to wear self-supplied magnification loupes during either …


Nanostructure Evolution Of Magnetron Sputtered Hydrogenated Silicon Thin Films, Dipendra Adhikari, Maxwell M. Junda, Sylvain X. Marsillac, Robert W. Collins, Nikolas J. Podraza Aug 2017

Nanostructure Evolution Of Magnetron Sputtered Hydrogenated Silicon Thin Films, Dipendra Adhikari, Maxwell M. Junda, Sylvain X. Marsillac, Robert W. Collins, Nikolas J. Podraza

Electrical & Computer Engineering Faculty Publications

Hydrogenated silicon (Si:H) thin films have been prepared by radio frequency (RF) magnetron sputtering. The effect of hydrogen gas concentration during sputtering on the resultant film structural and optical properties has been investigated by real time spectroscopic ellipsometry (RTSE) and grazing incidence x-ray diffraction (GIXRD). The analysis of in-situ RTSE data collected during sputter deposition tracks the evolution of surface roughness and film bulk layer thickness with time. Growth evolution diagrams depicting amorphous, nanocrystalline and mixed-phase regions for low and high deposition rate Si:H are constructed and the effects of process parameter (hydrogen gas concentration, total pressure and RF power) …