• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5250
  • 4908
  • 5
  • 3
  • 1
  • 1
  • 1
  • Tagged with
  • 10534
  • 10534
  • 10113
  • 10113
  • 10113
  • 3118
  • 3114
  • 3104
  • 3096
  • 3096
  • 3096
  • 2357
  • 2350
  • 2348
  • 1605
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

HIPAA protected delivery across Internet

Shirke, Parth P. 08 July 2016 (has links)
<p>VPN (Virtual Private Network) is a method of providing a secure connection between a source (computer/server) and a destination host. The connection is secured not on the basis of employing a dedicated channel between the source and destination host, but instead the connection is secured over the public internet. </p><p> VPN is implemented in a hospital&rsquo;s network to meet the Health Insurance Protection and Accountability Act (HIPAA) regulations. HIPAA is a directive that compels the medical centers and clinics to handle an individual&rsquo;s electronic medical record securely; free from any nature of breaching. </p><p> In an effort to execute the VPN on a hospital&rsquo;s network that complies with HIPAA, this project is focused on creating a network simulation with the VPN including other networking features. The VPN enabled network is accomplished using the GNS3 network simulation software. The data through the VPN tunnel are encoded and observed in Wireshark Software. </p><p> In the conclusion we will observe the state, unencrypted and encrypted, of the packets before and after, respectively, applying the VPN to the border routers through which the IP packets are traveling via the insecure Public Internet. </p>
2

Data acquisition via RS-232 and universal serial bus from a field programmable gate array

Liu, Xinyang. January 2009 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor: Julian, Alexander L. Second Reader: Cristi, Roberto. "December 2009." Description based on title screen as viewed on January 27, 2010. Author(s) subject terms: RS-232, USB, FPGA. Includes bibliographical references (p. 51-52). Also available in print.
3

Learning technologies used by CVTC electromechanical graduates in manufacturing

Martineau, Brenda L. January 2002 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2002. / Includes bibliographical references.
4

Cybersecurity of unmanned aircraft systems (UAS)

Gomez, Cesar A. 19 December 2015 (has links)
<p> The purpose of this research was to investigate the cybersecurity controls needed to protect Unmanned Aircraft Systems (UAS) to ensure the safe integration of this technology into the National Airspace System (NAS) and society. This research presents the current vulnerabilities present in UAS technology today along with proposed countermeasures, a description of national and international rules, standards, and activities pertaining to UAS and cybersecurity, and a minimum set of safety operational requirements which are recommended to be implemented by manufacturers of small UAS and mandated by governing agencies. UAS attacks are defined in three categories: hardware attack, wireless attack, and sensor spoofing. The future influx of small and hobby oriented UAS should consider a minimum set of regulated cyber safety standards right out of the box, such as Geofencing technology and isolated auto safety measures. The commonality between national and international cyber related activities point to several operational requirements, hardware limitations, and heightened UAS vulnerabilities. These include type of radio frequency spectrum that is used during operation, methods for detect and avoid, safety measures, lost link procedures, and corrupted data communications.</p>
5

Informativeness and the computational metrology of collaborative adaptive sensor systems

Hopf, Anthony P 01 January 2011 (has links)
Complex engineered systems evolve, with a tendency toward self-organization, which can, paradoxically, frustrate the aims of those seeking to develop them. The systems engineer, seeking to promote the development in the context of changing and uncertain requirements, is challenged by conceptual gaps that emerge within engineering projects, particularly as they scale up, that inhibit communication among the various stakeholders. Overall optimization, involving multiple criterion, is often expressed in the language of the individual parties, increasing the complexity of the overall situation, subsuming the participants within the evolution of the complex engineered system, conflating the objective and subjective in counter productive or inefficient ways that can arrest healthy development. The conventional pragmatic systems engineering approach to the resolution of such situations is to introduce architectural discipline by way of separation of concerns. In complex engineered systems projects, the crucial interface, at any level of abstraction, is between the technical domain experts and higher level decision makers. Bridging the ensuing conceptual gap requires models and methods that provide communication tools promoting a convergence of the conversation between these parties on a common "common sense" of the underlying reality of the evolving engineered system. In the interest of conceptual clarity, we confine our investigation to a restricted, but important general class of evolving engineered system, information gathering and utilizing systems. Such systems naturally resolve the underlying domain specific measures by reduction into common plausible information measures aimed at an overall sense of informativeness. For concreteness, we further restrict the investigation and the demonstration to a species that is well documented in the open literature: weather radar networks, and in particular to the case of the currently emerging system referred to as CASA. The multiobjective problem of objectively exploring the high dimensionality of the decision space is done using multiobjective genetic algorithms (MOGA), specifically the John Eddy genetic algorithms (JEGA), resulting in well formed Pareto fronts and sets containing Pareto optimal points within 20% of the ideal point. A visualization technique ensures a clear separation of the subjective criterion provided by the decision makers by superficially adding preferences to the objective optimal solutions. To identify the integrative objective functions and test patterns utilized in the MOGA analysis, explorations of networked weather radar technologies and configuration are completed. The explorations identify trends within and between network topologies, and captures both the robustness and fragility of network based measurements. The information oriented measures of fusion accuracy and precision are used to evaluate pairs of networked weather radars against a standardized low order vortex test pattern, resulting in a metrics for characterizing the performance of dual-Doppler weather radar pairs. To define integrative measures, information oriented measures abstracting over sensor estimators and parameters used to estimate the radial velocity and returned signal from distributed targets, specifically precipitation, are shown to capture the single radar predicted performance against standardized test patterns. The methodology bridges the conceptual gap, based on plausible information oriented measures, standardized with test patterns, and objectively applied to a concrete case with high dimensionality, allowed the conversation to converge between the systems engineer, decision makers, and domain experts. The method is an informative objective process that can be generalized to enable expansion within the technology and to other information gathering and utilizing systems and sensor technologies.
6

The challenges & opportunities of using low carbon energy supplies & their application to the developing world

Blenkinsopp, Thomas J. January 2014 (has links)
No description available.
7

Experimental and numerical analysis of river lake system and non-traditional water usage in a new Eco-City

Wang, Fei January 2013 (has links)
In recent years, Eco-City, which is designed with consideration for environmental impact and is inhabited by people dedicated to minimisation of required inputs of energy, air pollution and water pollution, has emerged as a way to address sustainability issues by adapting it to their local needs and context. The sustainability of urban water resources, water recycling and more efficient use of water resources will be the key features of the Eco-City. The current study takes Sino-Singapore Tianjin Eco-City as an example to investigate the sustainable use of water resources which focus on non-traditional water usage and ecological water requirements assessment. Firstly, the potential non-traditional water supply was evaluated based on the data acquired from the gauging station and the Eco-City planning data. It was found that rainwater has a great potential for domestic use in the Eco-City from June to September. Differing from other water consumption, ecological demand of the river lake system in the Eco-City was analysed by minimum ecological water requirements determination. An improved wetted perimeter method was used in order to determine the minimum ecological water requirements in the river system. It was found that the current monthly flow rates, with the exception of January to March, are fairly satisfactory. Secondly, an idealised river-lake system was assessed by hydraulics laboratory experimentation and 2D numerical modelling. The experimental and numerical investigations described in this study were undertaken to improve understanding of the hydrdynamic and flushing process within such a river lake system. A water diversion scheme was implemented in order to study lake recharge by river water during dry periods and under augmented flows. Fluorescent tracer experiments and related computer simulations were conducted to assess the performance of different parts of the system before and after implementing the diversion scheme. The results showed that such measures improved flushing, as seen from the perspective of reducing the mean detention time. However, due to poor cross-sectional velocity distribution, recharge alone had little impact on the overall mixing level in the lake waters. The effect of inserting flow deflectors near the lake inlet combined with flow augmentation was then assessed and was found to positively affect the distribution of solutes, by mitigating the occurrence of dead zones. Finally, an eco-hydraulic model was used to determine the levels of fish habitat suitability in the fluvial and lacustrine regions of a new Eco-City. This model has been developed by combining a depth integrated hydrodynamic and water quality model with a Habitat Suitability Index model. Carps were selected as the target species as they represent the major fish population in the study area. Hydrologic data recorded during 2001-2010 were analysed to determine the base flow, average flow and high flow rates, which were used to represent the discharges in the river for the three stages of the carp life cycle: overwintering, spawning and growth, respectively. Numerical model simulations were undertaken to determine the levels of habitat suitability for carps to live at these three life stages. The model results indicated that under the current flow regime the habitat suitability level in the lacustrine region is too low for carps at the growth and overwintering stages. DO depletion, overriding the role of velocity and depth, was attributed to the poorly suited habitat conditions in the lacustrine region. To improve the suitability conditions in the lacustrine region, a DO enhancement scheme was used. Model results showed that the scheme has significantly enhanced the water quality in the lacustrine region. Due to the high flow requirement for carps to spawn in the fluvial region, further numerical model simulations were undertaken to investigate the effect of flow augmentation on the carp spawning habitat suitability.
8

Integrated physical-Fenton remediation of petroleum-contaminated soil using ethyl lactate as a green solvent

Jalilian Ahmadkalaei, Seyedeh Pegah January 2018 (has links)
The huge amount of petroleum hydrocarbons contaminated sites is the heritage of a long history of fossil fuels usage. Reducing petroleum hydrocarbons levels in contaminated soils by Fenton reaction and with the aid of one or two agents such as solvents, surfactants, or vegetable oils has been studied in recent years, with successful reported results. Nonetheless, destruction of the aliphatic fraction of total petroleum hydrocarbon (TPH) by Fenton reaction has been studied to a lesser extent as compared to the aromatic fraction of TPH. Additionally, studies regarding the effect of humic acid (HA) on Fenton reaction reported contradictory results, and more research is necessary to clarify HA effects. Lastly, although achieving the highest efficiency is the main objective of soil remediation technologies, the environmental side effects of the applied processes should be considered as important as the efficiency. In light of these, the main aim of this project was to increase Fenton treatment efficiency by using an environmental friendly solvent, ethyl lactate (EL). The project objectives included determining optimum levels for the reagents of Fenton reaction and desorption process such as hydrogen peroxide (H2O2) and EL, identifying the kinetic of TPH desorption and destruction of petroleum hydrocarbons by Fenton reaction in addition to analysing the effects of EL on these processes. Through desorption tests, EL/water solution demonstrated great ability to increase the removal efficiency and desorption of sorbed TPH. Desorption by EL/water solution consisted of a very fast desorption stage followed by a slow stage. After 30 min of desorption, the removal efficiency of TPH increased from 63% to 81% for EL=25% and EL=100%, respectively. The initial desorption rate for 25% and 100% were 1.625 mg/min and 3.368 mg/min, respectively. The results of batch experiments indicated that EL%=10% was the optimum value for the EL-modified Fenton reaction. After 4 h, an increase in H2O2 concentration from 0.1 M to 2 M at L/S=2 and EL=25% increased the removal efficiency of TPH from 68.41% to 90.21%. HA addition up to 150 mg/l was also studied. For fraction 1, adding HA led to an increase in removal efficiency while for fraction 2, only HA=150mg/l had higher removal efficiency than the HA=0 case and for fraction 3, addition of HA in the studied range could not increase the removal efficiency. A good compatibility of zero-valent iron nanomaterial with H2O2 was proved. Laboratory column experiments were finally carried out to remove petroleum hydrocarbons from diesel-contaminated soil with EL to reproduce the conditions of in-situ treatment. The remaining diesel in soil decreased by increasing H2O2 molarity from 0.1 M to 0.5 M whereas a further increase to 2 M led to an increase in remaining diesel in soil. The stability of H2O2 in EL has been observed which signifies good potential for in-situ applications. Overall, the project has demonstrated the feasibility of EL-modified Fenton reaction for the remediation of petroleum-contaminated soil.
9

Asymptotically optimal path planning and surface reconstruction for inspection

Papadopoulos, Georgios January 2014 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 163-179). / Motivated by inspection applications for marine structures, this thesis develops algorithms to enable their autonomous inspection. Two essential parts of the inspection problem are (1) path planning and (2) surface reconstruction. On the first problem, we develop a novel analysis of asymptotic optimality of control-space sampling path planning algorithms. This analysis demonstrated that asymptotically optimal path planning for any Lipschitz continuous dynamical system can be achieved by sampling the control space directly. We also determine theoretical convergence rates for this class of algorithms. These two contributions were also illustrated numerically via extensive simulation. Based on the above analysis, we developed a new inspection planning algorithm, called Random Inspection Tree Algorithm (RITA). Given a perfect model of a structure, sensor specifications, robot dynamics, and an initial configuration of a robot, RITA computes the optimal inspection trajectory that observes all surface points on the structure. This algorithm uses of control-space sampling techniques to find admissible trajectories with decreasing cost. As the number of iterations increases, RITA converges to optimal control trajectories. A rich set of simulation results, motivated by inspection problems for marine structures, illustrate our methods. Data gathered from all different views of the structure are assembled to reconstruct a 3D model of the external surfaces of the structure of interest. Our work also involved field experimentation. We use off-the-shelf sensors and a robotic platform to scan marine structures above and below the waterline. Using such scanned data points, we reconstruct triangulated polyhedral surface models of marine structures based on Poisson techniques. We have tested our system extensively in field experiments at sea. We present results on construction of various 3D surface models of marine structures, such as stationary jetties and slowly moving structures (floating platforms and boats). This work contributes to the autonomous inspection problem for structures and to the optimal path, inspection and task planning problems. / by Georgios Papadopoulos. / Ph. D.
10

The kinetics of the reaction of carbon with carbon dioxide

Wu, Pao-chen, 1920- January 1950 (has links)
Thesis (Sc.D.)--Massachusetts Institute of Technology. Dept. of Chemical Engineering, 1950. / Vita. / Bibliography: leaves 225-228. / by Pao-chen Wu. / Sc.D.

Page generated in 0.1444 seconds