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  • 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.
761

Study and Implementation of Patient Data Collection and Presentation for an eHealth Application

Song, Qunying, Xu, Jingjing January 2013 (has links)
This degree project is a part of information and communication technology supported self-care system for the diabetes, mainly in diabetes data collection and visualization. The report is organized in four main sections: investigation and internet search, literature review, application design and implementation, system test and evaluation. Existed applications and research studies has been compared and, a responsive web application is developed aiming at providing relevant functionalities and services regarding diabetes self-management.
762

Replication, Security, and Integrity of Outsourced Data in Cloud Computing Systems

Barsoum, Ayad Fekry 14 February 2013 (has links)
In the current era of digital world, the amount of sensitive data produced by many organizations is outpacing their storage ability. The management of such huge amount of data is quite expensive due to the requirements of high storage capacity and qualified personnel. Storage-as-a-Service (SaaS) offered by cloud service providers (CSPs) is a paid facility that enables organizations to outsource their data to be stored on remote servers. Thus, SaaS reduces the maintenance cost and mitigates the burden of large local data storage at the organization's end. For an increased level of scalability, availability and durability, some customers may want their data to be replicated on multiple servers across multiple data centers. The more copies the CSP is asked to store, the more fees the customers are charged. Therefore, customers need to have a strong guarantee that the CSP is storing all data copies that are agreed upon in the service contract, and these copies remain intact. In this thesis we address the problem of creating multiple copies of a data file and verifying those copies stored on untrusted cloud servers. We propose a pairing-based provable multi-copy data possession (PB-PMDP) scheme, which provides an evidence that all outsourced copies are actually stored and remain intact. Moreover, it allows authorized users (i.e., those who have the right to access the owner's file) to seamlessly access the file copies stored by the CSP, and supports public verifiability. We then direct our study to the dynamic behavior of outsourced data, where the data owner is capable of not only archiving and accessing the data copies stored by the CSP, but also updating and scaling (using block operations: modification, insertion, deletion, and append) these copies on the remote servers. We propose a new map-based provable multi-copy dynamic data possession (MB-PMDDP) scheme that verifies the intactness and consistency of outsourced dynamic multiple data copies. To the best of our knowledge, the proposed scheme is the first to verify the integrity of multiple copies of dynamic data over untrusted cloud servers. As a complementary line of research, we consider protecting the CSP from a dishonest owner, who attempts to get illegal compensations by falsely claiming data corruption over cloud servers. We propose a new cloud-based storage scheme that allows the data owner to benefit from the facilities offered by the CSP and enables mutual trust between them. In addition, the proposed scheme ensures that authorized users receive the latest version of the outsourced data, and enables the owner to grant or revoke access to the data stored by cloud servers.
763

Radar as a remote sensor of regions of supercooled cloud water

Massambani, Oswaldo. January 1982 (has links)
A new technique, named Vertical Profile Indicator (VPI), which uses the vertical structure of the reflectivity profile to delineate regions most likely to have supercooled liquid water content (SCLWC) within the precipitation field, was developed. When the aircraft flew in the "active regions" (as defined by the VPI technique) it was found that 90% of the time significant amounts of SCLWC were observed. / Using Doppler and "Quasi-Doppler" radar data, high convergence cores (> 3.0 x 10('-3) s('-1)) and updraft activity were observed to occur preferentially in the "active regions". During the 1981 winter-spring period of the Precipitation Enhancement Project in the Duero Basin of Spain percentages of "active regions" in relation to the whole precipitation field, and in relation to the total radar observation area, did not exceed 47% and 18% respectively. / The VPI technique provides information which may be used to direct research aircraft to cloud regions containing SCLWC to allow measurements of the time evolution of their microphysical state. These measurements would permit a better estimation of the residence time of the SCLWC and its removal rates. This is a key parameter for better understanding the microphysical properties of clouds and consequently the possibility of artificial modification of precipitation.
764

Representing droplet size distribution and cloud processes in aerosol-cloud-climate interaction studies

Hsieh, Wei-Chun 04 May 2009 (has links)
The indirect effect of aerosols expresses how changes in aerosols would influence clouds and cause impacts on Earth's climate and hydrological cycle. The current assessment of the interactions between aerosols and clouds is uncertain and parameterizations used to represent cloud processes are not well constrained. This thesis first evaluates a cloud activation parameterization by investigating cloud droplet number concentration closure for stratocumulus clouds sampled during the 2005 MArine Stratus Experiment (MASE). Further analysis of the droplet size distribution characteristics using the extended parameterization is performed by comparing the predicted droplet spectra with the observed ones. The effect of dynamical variability on the droplet size distribution evolution is also investigated by considering a probability density function for updraft velocity. The cumulus and stratocumulus cloud datasets from in-situ field measurements of NASA's Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment (CRYSTAL-FACE) and Coastal STRatocumulus Imposed Perturbation Experiment (CSTRIPE) campaigns are used for this task. Using the same datasets, the autoconversion rate is calculated based on direct integration of kinematic collection equation (KCE). Six autoconversion parameterizations are evaluated and the effect of turbulence on magnifying collection process is also considered. Finally, a general circulation model (GCM) is used for studying the effect of different autoconversion parameterizations on indirect forcing estimates. The autoconversion rate given by direct KCE integration is also included by implementing a look-up table for collection kernels. Although these studies add more variability to the current estimate of aerosol indirect forcing, they also provide direction towards a more accurate assessment for climate prediction.
765

Developmental of a Vapor Cloud Explosion Risk Analysis Tool Using Exceedance Methodology

Alghamdi, Salem 2011 August 1900 (has links)
In development projects, designers should take into consideration the possibility of a vapor cloud explosion in the siting and design of a process plant from day one. The most important decisions pertinent to the location of different process areas, separation between different areas, location of occupied buildings and overall layout may be made at the conceptual stage of the project. During the detailed design engineering stage the final calculation of gas explosion loads is an important activity. However, decisions related to the layout and location of occupied buildings at this stage could be very costly. Therefore, at the conceptual phase of the development project for a hydrocarbon facility, it would be helpful to get a picture of possible vapor cloud explosion loads to be used in studying various options. This thesis presents the analytical parameters that are used in vapor cloud explosion risk analysis. It proposes a model structure for the analysis of vapor cloud explosion risks to buildings based on exceedance methodology. This methodology was developed in a computer program which is used to support this thesis. The proposed model considers all possible gas release scenarios through the use of the Monte Carlo simulation. The risk of vapor cloud explosions can be displayed using exceedance curves. The resulting model provides a predictive tool for vapor cloud explosion problems at the early stages of development projects, particularly in siting occupied buildings in onshore hydrocarbon facilities. It can also be used as a quick analytical tool for investigating various aspects of vapor cloud explosions. This model has been applied to a case study, a debutanizer process unit. The model was used to explore the different alternatives of locating a building near the facility. The results from the model were compared to the results of other existing software to determine the model validity. The results show that the model can effectively examine the risk of vapor cloud explosions.
766

A multi-molecular line study of an entire giant molecular cloud

Lo, Wing-Chi Nadia , Physics, Faculty of Science, UNSW January 2009 (has links)
A unified theory of star formation remains one of the major unsolved issues in astrophysics. Presented here are the results of multi-molecular lines mapping of the entire giant molecular cloud G333, comprised sites of low- and high-mass star forming regions in various evolution stages of star formation. The result shows the spatial distribution of CS, HCO+, HCN and HNC are similar on large scales, while N2H+ seems to trace preferentially the very densest regions, possibly due to the chemical difference, that N2H+ is sensitive to temperature and readily destroyed by CO. Two analysis methods were used to characterise this large set of data cubes: GAUSSCLUMPS and principal component analysis (PCA). We found the clumps are heavily fragmented with a beam filling factor of ~0.2. We found no correlation between clump radius and line width, contradicts to Larson's Law. Possible explanation is the clumps are fragmented and unresolved with the resolution of Mopra beam, thus the decomposed clump radius is blended and no physical properties can be interpreted. PCA of the velocity dimension found no significant differences among CS, HCO+, HNC and C2H line emissions, suggesting these four molecules are `well-mixed' on large scale, possibly by turbulence. PCA of the integrated emission maps separates molecules into low (13CO and C18O) and high (the rest) density tracers, identifies anti-correlation between HCO+ and N2H+ (due to the depletion of CO). The possibility of removing the scanning patterns of the `on-the-fly' mapping with PCA was also explored. The detection of broad thermal SiO from the massive dense cold core G333.125-0.562, along with other collected transitions, suggesting the core will host massive star formation and the SiO emission arises from shocks associated with an outflow in the cold core. Result of the modelling infall with 3D radiative transfer code using the derived physical parameters have successfully reproduce the line profiles. Recent observation of the 3 and 7 mm continuum emission suggestive of warm dust emission rather than free-free emission from HII, further supports the core is in a very young stage of star formation.
767

Effects of solar heating on the indirect effect of aerosols as deduced from observations of ship tracks /

Christensen, Matthew W. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 47-49). Also available on the World Wide Web.
768

Seasonal and interannual variability of tropical diurnal warming of sea surface temperatures

Weitlich, Derrick Karl. Clayson, Carol Anne. January 2005 (has links)
Thesis (M.S.)--Florida State University, 2005. / Advisor: Dr. Carol Anne Clayson, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed June 16, 2005). Document formatted into pages; contains xii, 82 pages. Includes bibliographical references.
769

A numerical investigation of the impact of ice hydrometeors on the intensity of Hurricane Isabel

Sheermohamed, Jordanna. Clayson, Carol Anne. January 1900 (has links)
Thesis (M.S.)--Florida State University, 2005. / Advisor: Dr. Carol Anne Clayson, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed June 28, 2005). Document formatted into pages; contains x, 62 pages. Includes bibliographical references.
770

Pion production in neutron-proton collisions at bevatron energies

Holmquist, Fred Nels. January 1958 (has links)
Thesis--University of California, Berkeley, 1958. / "Physics and Mathematics" -t.p. Includes bibliographical references (p. 123-125).

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