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Determination Of The Impact Of A Human Capital Decision Cost Model On The Economic Performance Measures Of A Technical Services Company, Jeffery A. Temple

Engineering Management & Systems Engineering Theses & Dissertations

Human Capital has a major impact on cash flow management decisions in a Technical Services company. Decisions to hire or terminate employees to meet contract requirements affect the company's economic value. The objective of this research is to develop a model that assists management in establishing a starting point in making, as efficiently as possible, those decisions that impact employees' lives. To understand that impact, the operations and economic parameters of a Technical Services company are compared with those of a manufacturing company. This analysis establishes two · essential points for Technical Services organizations; first, that the capital investment decision …

Simulation Optimization Studies Of Routing And Process Flow Problems, Satish Ravichandran

Electrical & Computer Engineering Theses & Dissertations

Computer aided simulation is emerging as a powerful tool for numerical analysis and in conducting performance evaluations of complex systems that depend on a multitude of variables. The primary objective in such simulation studies is to gauge the performance of the system under a various constraints and operating conditions. The effects of changing the operating parameter space can thus be analyzed without having to implement costly changes. Simulations are also carried out for the baseline scenarios to verity and validate the basic underlying system model. In this thesis research, two practical problems were studied through numerical modeling, and optimized solutions …

Optimal Aeroelastic Vehicle Sensor Placement For Root Migration Flight Control Applications, Abdul Ghafoor Al-Shenhabi

Mechanical & Aerospace Engineering Theses & Dissertations

An important step in control design for elastic systems is the determination of the number and location of control system components, namely sensors. The number and placement of sensors can be critical to the robust functioning of active control systems, especially when the system of interest is a large high-speed aeroelastic vehicle. The position of the sensors affects not only system stability, but also the performance of the closed-loop system. In this dissertation, a new approach for sensor placement in the integrated rigid and vibrational control of flexible aircraft structures is developed. Traditional rigid-body augmentation objectives are addressed indirectly through …

Adsorption Of Inorganic And Organic Ligands Onto Aluminum Hydroxide And Its Effect In Water Treatment, Peter Pommerenk

Civil & Environmental Engineering Theses & Dissertations

The inorganic anions fluoride, sulfate, and orthophosphate are ubiquitous substances in aqueous environments. These chemicals are also applied in drinking water treatment processes where fluoridation, coagulation with sulfate-based metal salts, or the use of passivating corrosion inhibitors or sequestering agents is practiced. If these ions are present at elevated levels in raw waters or added in the treatment train at points other than directly before entering a finished water reservoir, they can exert a negative influence on the removal of particles and natural organic matter.

Although the water chemistry of these inorganic ions seems to be well understood, their potential …

Spice-Based Heat Transport Model For Non-Intrusive Thermal Diagnostic Applications, Michael Stelzer

Electrical & Computer Engineering Theses & Dissertations

Nondestructive material testing and diagnostics play an important role in reliability analysis, component wear-out testing, life-cycle estimates, and safety inspections. Of the several techniques available for nondestructive inspections, thermal analysis has been chosen to be the focus of this thesis research. An equivalence between the system of equations for the heat flow problem, and the variables of circuit theory suggests that an electrical model can be constructed to represent the actual thermal system. This electrical model is constructed based upon a finite difference discretization of the heat flow equation. Using these associations a basic one-dimensional electrical model has been constructed …

Time-Resolved Electron Diffraction Studies Of Phase Transitions At Low-Index Germanium Surfaces, Xinglin Zeng

Electrical & Computer Engineering Theses & Dissertations

The phase transitions at the low-index surfaces of germanium were investigated using conventional and 100-ps time-resolved reflection high-energy electron diffraction. For the time-resolved studies, the surface is heated by 100-ps laser pulse while a synchronized electron beam probes the structure. When heated by 100-ps laser pulse, Ge(111)-c(2x8) and Ge(100)-(2x1) reconstruction is seen to overheat above the onset temperatures for the disordering under thermodynamic equilibrium. Slow heating shows that the adatoms in the Ge(111)-c(2x8) reconstruction state start to disorder at ∼510 K and are converted to a totally disordered adatom arrangement at 573 K. For heating with 100-ps laser pulses, time-resolved …

Elastic Properties, Strength And Damage Tolerance Of Pultruded Composites, Mrinal Chandra Saha

Mechanical & Aerospace Engineering Theses & Dissertations

Pultruded composites are candidate materials for civil engineering infrastructural applications due their higher corrosion resistance and lower life cycle cost. Efficient use of materials like structural members requires thorough understanding of the mechanism that affects their response. The present investigation addresses the modeling and characterization of E-glass fiber/polyester resin matrix pultruded composites in the form of sheets of various thicknesses.

The elastic constants were measured using static, vibration and ultrasonic methods. Two types of piezoelectric crystals were used in ultrasonic measurements. Finally, the feasibility of using a single specimen, in the form of a circular disk, was shown in measuring …

A Substructuring Technique With Application To Spot Weld Placement Design, Yang Wang

Mechanical & Aerospace Engineering Theses & Dissertations

It is quite common in the industry to use various interface methods, such as welding, fasteners, bolts, adhesive bonding, etc., to join substructures together. The quality of the assembled structure is directly related to the type of the interface methods used in the manufacturing process. Thus, it is important to include the interface conditions as part of design variables in any design process. To this end, this work develops a reanalysis method that can efficiently analyze structures with variations on the interface conditions. This reanalysis method is based upon a new two-step substructuring technique. The first step performs substructural level …

On Multifunctional Collaborative Methods In Engineering Science, Jonathan B. Ransom Sr.

Mechanical & Aerospace Engineering Theses & Dissertations

Engineers are challenged to produce better designs in less time and for less cost. Hence, to investigate novel and revolutionary design concepts, accurate, high-fidelity data must be assimilated rapidly into the design, analysis and simulation process. This data assimilation should consider diverse mathematical modeling and multi-discipline interactions necessitated by concepts exploiting advanced materials and structures. Integrated high-fidelity methods with diverse engineering applications provide the enabling technologies to assimilate these high-fidelity, multi-disciplinary data rapidly at an early stage in the design. These integrated methods must be multifunctional, collaborative and applicable to the general field of engineering science and mechanics.

Multifunctional methodologies …

Coherent Differential Absorption Lidar For Combined Measurement Of Wind And Trace Atmospheric Gases, Grady James Koch

Electrical & Computer Engineering Theses & Dissertations

A lidar system was developed for making combined range-resolved measurements of wind speed and direction, water vapor concentration, and carbon dioxide concentration in the atmosphere. This lidar combines the coherent Doppler technique for wind detection and the differential absorption lidar (DIAL) technique to provide a multifunctional capability. DIAL and coherent lidars have traditionally been thought of and implemented as separate instruments, but the research reported here has shown a demonstration of combining the coherent and DIAL techniques into a single instrument using solid-state lasers. The lasers used are of Ho:Tm:YLF, which operates at a wavelength of 2 μm. This wavelength …

Future Research Vessels, Larry P. Atkinson

CCPO Publications

The academic research vessel fleet in the United States is embarking on a great experiment. By 2004 we will know if SWATH vessels such as the Mlo Moana and the possible built Woods Hole Oceanographic Institution coastal SWATH have such great advantages that all future vessels will be of SWATH design. Or, we will find that the two hull forms have distinct niches and the fleet will evolve with a strategic mix. Regardless of the Mure hull form research vessels will grow in size to accommodate advanced technology and the people to run and maintain it. The research vessel will …

Xenon Excimer Emission From Pulsed Microhollow Cathode Discharges, M. Moselhy, R. H. Stark, K. H. Schoenbach, U. Kogelschatz

Bioelectrics Publications

By applying electrical pulses of 20 ns duration to xenon microplasmas, generated by direct current microhollow cathode discharges, we were able to increase the xenon excimer emission by more than an order of magnitude over direct current discharge excimer emission. For pulsed voltages in excess of 500 V, the optical power at 172 nm was found to increase exponentially with voltage. Largest values obtained were 2.75 W of vacuum-ultraviolet optical power emitted from a single microhollow cathode discharge in 400 Torr xenon with a 750 V pulse applied to a discharge. Highest radiative emittance was 15.2 W/cm². The …

Global Engineering In An Interconnected World: An Upper Division General Education Cluster At Old Dominion University, Sushil Chaturvedi, Gary Crossman, William Swart, Joseph Betit

Mechanical & Aerospace Engineering Faculty Publications

The “Global Engineering in an Interconnected World” cluster of courses fosters among students an awareness and understanding of global technology, quality assurance standards, and differences in cultural, communication, and business practices and their impact on a global work environment. This cluster will prepare the growing numbers of students who will accept employment with global firms or find themselves part of a merger or strategic alliance involving multinational corporations. This newly approved cluster of five courses described in the paper has been approved by the University for satisfying University upper-division general education requirements. As a consequence, students choosing this route to …

Prototype Development For A Leak-Preventive Toilet Flush System- An Met Senior Design (Capstone) Project, Cheng Y. Lin

Engineering Technology Faculty Publications

A senior design (Capstone) project for three mechanical engineering technology students at Old Dominion University is described. A prototype design is presented to perform the functional test of a leak-preventive toilet system. There are two major leaks in the toilet water tank. In the first case, leaking occurs when the seal in the water tank becomes aged. The leak is very easy to detect visually, since the outside of the tank and the floor becomes wet. In the second case, leak occurs when the flapper valve can't complete shut off the water, due to corrosion or damage of the rubber …

Stm And Electrochemical Investigation Of Homoepitaxial Boron-Doped Cvd Diamond Films, John B. Cooper, Jason A. Moulton, Sacharia Albin, Bing Xiao

Chemistry & Biochemistry Faculty Publications

Homoepitaxial growth of boron-doped CVD diamond films was carried out on (100) and (111) oriented substrates. Atomic resolution images were obtained for both (100) and (111) surfaces using scanning tunneling microscopy. STM images reveal the presence of a 2x1-monohydride reconstruction for the untreated (100) surface and a lxl reconstruction for the untreated (111) surface. No other atomically resolved reconstructions were observed under a wide range of growth conditions. Non-aqueous electrochemical investigations were carried out on the films exhibiting atomically resolved reconstructions. Evidence for potential-induced surface-reconstruction and surface chemical modification of the (100) 2xl-monohydride surface has been observed.

Resonant Energy Transfer From Argon Dimers To Atomic Oxygen In Microhollow Cathode Discharges, M. Moselhy, R. H. Stark, K. H. Schoenbach, U. Kogelschatz

Bioelectrics Publications

The emission of atomic oxygen lines at 130.2 and 130.5 nm from a microhollow cathode discharge in argon with oxygen added indicates resonant energy transfer from argon dimers to oxygen atoms. The internal efficiency of the vacuum-ultraviolet (VUV) radiation was measured as 0.7% for a discharge in 1100 Torr argon with 0.1% oxygen added. The direct current VUV point source operates at voltages below 300 V and at current levels of milliamperes.

Self-Consistent Simulations Of Electroporation Dynamics In Biological Cells Subjected To Ultrashort Electrical Pulses, R. P. Joshi, Q. Hu, R. Aly, K. H. Schoenbach, H. P. Hjalmarson

Bioelectrics Publications

The temporal dynamics of electroporation of cells subjected to ultrashort voltage pulses are studied based on a coupled scheme involving the Laplace, Nernst-Plank, and Smoluchowski equations. A pore radius dependent energy barrier for ionic transport, accounts for cellular variations. It is shown that a finite time delay exists in pore formation, and leads to a transient overshoot of the transmembrane potential V_mem beyond 1.0 V. Pore resealing is shown to consist of an initial fast process, a 10⁻⁴s delay, followed by a much slower closing at a time constant of about 10 ⁻¹s. This establishes a …

Innovative Student Research Projects, Alok K. Verma

Engineering Technology Faculty Publications

Innovation in capstone projects, which should not be limited by external funding, is discussed. It is found that the properly designed unfunded senior projects can offer quality learning experience for students. Involvement of industry is a key factor for a successful capstone course. Innovative research projects can be offered under various organizational framework.

Arc - An Oai Service Provider For Digital Library Federation, Xiaoming Liu, Kurt Maly, Mohammad Zubair, Michael L. Nelson

Computer Science Faculty Publications

The usefulness of the many on-line journals and scientific digital libraries that exist today is limited by the inability to federate these resources through a unified interface. The Open Archive Initiative (OAI) is one major effort to address technical interoperability among distributed archives. The objective of OAI is to develop a framework to facilitate the discovery of content in distributed archives. In this paper, we describe our experience and lessons learned in building Arc, the first federated searching service based on the OAI protocol. Arc harvests metadata from several OAI compliant archives, normalizes them, and stores them in a search …

Smart Objects And Open Archives, Michael L. Nelson, Kurt Maly

Computer Science Faculty Publications

Within the context of digital libraries (DLs), we are making information objects "first-class citizens". We decouple information objects from the systems used for their storage and retrieval, allowing the technology for both DLs and information content to progress independently. We believe dismantling the stovepipe of "DL-archive-content" is the first step in building richer DL experiences for users and insuring the long-term survivability of digital information. To demonstrate this partitioning between DLs, archives and information content, we introduce "buckets": aggregative, intelligent, object-oriented constructs for publishing in digital libraries. Buckets exist within the "Smart Object, Dumb Archive" (SODA) DL model, which promotes …

Buckets: Smart Objects For Digital Libraries, Michael L. Nelson

Computer Science Faculty Publications

Current discussion of digital libraries (DLs) is often dominated by the merits of the respective storage, search and retrieval functionality of archives, repositories, search engines, search interfaces and database systems. While these technologies are necessary for information management, the information content is more important than the systems used for its storage and retrieval. Digital information should have the same long-term survivability prospects as traditional hardcopy information and should be protected to the extent possible from evolving search engine technologies and vendor vagaries in database management systems. Information content and information retrieval systems should progress on independent paths and make limited …

Meeting Research & Publication Requirements In An Undergraduate E T Program Through Senior Design Projects, Alok K. Verma

Engineering Technology Faculty Publications

(First paragraph) Success in an Engineering Technology programs has been traditionally evaluated based upon three factors namely, Teaching, Research and Service. While the relative ranking of these factors is arguable 1,5, it is the research (and the associated requirement of publication) which causes great anxiety for faculty in ET programs. This is specially true, in view of increasing emphasis placed on the research and publication by the ET programs in the nation. A number of articles have been written on the promotion and tenure requirements 2,3,4. Most of these publications discuss the general requirements of promotion and tenure and the …

An Integrated Risk Analysis Methodology In A Multidisciplinary Design Environment, Katrina R. Hampton

Engineering Management & Systems Engineering Theses & Dissertations

Design of complex, one-of-a-kind systems, such as space transportation systems, is characterized by high uncertainty and, consequently, high risk. It is necessary to account for these uncertainties in the design process to produce systems that are more reliable. Systems designed by including uncertainties and managing them, as well, are more robust and less prone to poor operations as a result of parameter variability.

The quantification, analysis and mitigation of uncertainties are challenging tasks as many systems lack historical data. In such an environment, risk or uncertainty quantification becomes subjective because input data is based on professional judgment. Additionally, there are …

A Model To Evaluate The Effect Of Organizational Adaptation, Holly A. H. Handley, Alexander H. Levis

Engineering Management & Systems Engineering Faculty Publications

When an organization’s output declines due to either internal changes or changes in its external environment, it needs to adapt. In order to evaluate the effectiveness of different adaptation strategies on organizational per- formance, an organizational model composed of individual models of a five stage interacting decision maker was designed using an object oriented design approach and implemented as a Colored Petri net. The concept of entropy is used to calculate the total activity value, a surrogate for decision maker workload, based on the functional partition and the adaptation strategy being implemented. The individual decision maker’s total activity is monitored, …

A Study Of Financial Analysis Expectations And Practices In The Engineering Management Workplace, Paul Kauffmann, Resit Unal, Andres Sousa-Poza, William Peterson

Engineering Management & Systems Engineering Faculty Publications

This paper describes an on-going study of Master of Engineering Management (MEM) students and the financial analysis related job expectations and environment they face. The objective of this effort is to provide enhanced understanding of these requirements so that instructional content in the related courses can be focused to meet these needs. To achieve this goal, the study segments findings based on a range of organizational and job level characteristics to identify critical differences in the financial work environment and the financial tools that are employed. Preliminary findings are discussed in this paper and contrasts between public and private sector …

Incorporating Heterogeneity In Command Center Interactions, Holly A. H. Handley, Alexander H. Levis

Engineering Management & Systems Engineering Faculty Publications

One of the many complexities of multinational coalition operations stems from differences in culture, military procedures, and command and control processes between the cooperating command centers. These differences can influence the interactions between decision makers of different command centers and can affect the outcome of the coalition operation. A coalition model, composed of individual models of the five-stage interacting decision maker model, was used in a virtual experiment. The subjective parameters included in the decision maker model can be any attribute that characterizes the heterogeneity of the decision makers. In this case, the parameters of power distance and uncertainty avoidance …

Levels Of Interoperability In Coalition Systems, Holly A. H. Handley, Alexander H. Levis, Michel Bares

Engineering Management & Systems Engineering Faculty Publications

Systems of different command centers that are brought together in a coalition operation must have some level of interoperability in order to work together. Bares [2000] has introduced a formalism of three interoperability domains that describe the ability of the systems to define their own level of interoperability within the coalition by assessing their own and the other systems’ ability to interact on actions of the coalition. The lowest domain, interconnectivity, reflects the ability to exchange messages; this level must already have been achieved in order for the systems to participate in the coalition. The second domain, interoperability, reflects a …

A Noninvasive Test For Vesico-Ureteric Reflux In Children, R. A. Mevorach, B. Cilento, S. Zahorian, C. Badgett, R. Walker, A. Atala, S. Iannello, M. Meyer

Electrical & Computer Engineering Faculty Publications

Objective To report the development and testing of a device for the noninvasive diagnosis of vesico‐ureteric reflux (VUR) which avoids the need for urethral catheterization (currently required to reliably determine the presence of VUR), and which thus avoids the anxiety of parents and patients that causes many families to refuse such evaluation.

Patients and methods Fifty‐four children (49 girls and five boys, mean age 7.2 years, range 4–14) previously evaluated as having VUR volunteered to participate; no child was symptomatic at the time of the study. Refluxing units were known to be present by voiding cysto‐urethrography (within 1 year, mean …

Boron-Doped Homoepitaxial Diamond (100) Film Investigated By Scanning Tunneling Microscopy, Bing Xiao, Weihai Fu, Sacharia Albin, Jason Moulton, John Cooper

Electrical & Computer Engineering Faculty Publications

Conducting epitaxial diamond films of high quality are essential for many diamond studies and diamond electronic device fabrication. We have grown boron-doped epitaxial diamond films on type Ila natural diamond (100) substrates by microwave plasma chemical vapor deposition. A gas mixture of H₂/CH₄ was used. Boron doping was done by placing solid sources of pure boron in the microwave plasma. Homoepitaxial films with atomic smoothness were achieved under the following growth conditions: substrate temperature 900 °C, gas pressure 40 Torr, and gas flow rates of H₂/CH₄ = 900/7.2 seem. The growth rate was 0.87 …

Characterization Of The Biological Activities Of Recombinant Fusion Protein Green Fluorescent Protein/Human Zona Pellucida Protein 3 (Gfp/Hzp3), Zhiyong Lin

Theses and Dissertations in Biomedical Sciences

Despite numerous reports indicating the successful production of bioactive recombinant ZP3, no report has shown the rhZP3 having direct binding activity with human sperm. Recombinant ZP3 generated from our previous study displayed binding activity with human sperm through indirect evidence from hemizona assay (HZA).

This present study focused on the production of recombinant ZP3 with direct binding activity with human sperm. Through the application of a pEGFP expression vector, fusion protein GFP/ZP3 was successfully generated and expressed. The expression of GFP/ZP3 was evidenced by RT-PCR and western blot. The fusion protein was partially purified by Ni-NTA affinity column from cell …