Detecting open surfaces in 3D

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.Cataloged from PDF version of thesis.Includes bibliographical references (p. 99-104).We present a novel level-set method for representing and detecting open surfaces embedded in three-dimensional image volumes. Open surfaces are two-dimensional manifolds with a one-dimensional boundary lying within a three-dimensional volume. Distinct portions of a closed surface can be modeled as open surfaces, as can very thin volumes with negligible thickness. To detect open surfaces, we propose an interface likelihood model that captures the image appearance along a profile normal to the open surface. This allows statistical modeling of more complex surface-appearance characteristics than just voxel intensities or gradients. Appearance models of the surface are used in the level-set framework in two ways: firstly, to evolve the open surface in the normal direction for the purpose of detecting the location and shape of the surface, and secondly, to evolve the boundary of the open surface in a direction tangential to the surface in order to delineate the extent of the surface. We show that our models are well suited to detecting structures of interest in three-dimensional medical and geological images, and demonstrate their utility on challenging structural magnetic resonance (MR) datasets and seismic-reflection volumes.by Biswajit Bose.Ph.D

Salugenic Relationships that Rehumanise: A Grounded Theory of Congruence

This study is a mixed methods study, conducted in a therapeutic faith community, using quantitative (CGI, SCL-90-R and WHODAS-II) and qualitative interview data that generated a theory of congruence. Early findings demonstrated that context changed the dynamics of the relationship between the researcher and the participants. This led to dissemblance in responses to the outcome measures. A critical realist ‘value laden’ approach was used which challenges the existing tendency to privilege quantitative over qualitative data by proposing that context and subjectivity are involved in all aspects of interpersonal research. The theory of congruence proposes that the key to personal positive change is the ability to recognise personal incongruence. Incongruence was identified as a fragmented self, social isolation, crisis of faith and lack of environment ‘fit’. Becoming congruent was identified in three areas, a whole self, a social self and a spiritual self. The process of becoming congruent with self begins with external sources that are relationships and environment. These relationships have been termed salugenic (health-producing) relationships, which are voluntary, volitional and mutual. Such relationships resist hierarchy, promoting positive power and autonomy. The theory of congruence proposes that individuals who have been socially isolated learn how to form salugenic relationships that facilitate salugenic emotion. A congruent environment is where individuals feel they belong, find hope, safety and freedom. It is also a place that is congruent with their beliefs. The combination of congruent relationships and environment leads to the process of finding congruence with self within the context of having personal choice. The participants in this study were incongruent with professionalised and structuralised services that can be too rigid to meet the needs of the emotionally and mentally ill. Congruence theory can be applied by any organisation to prioritise structure, relationship and choice that rehumanises mental health care

Terrain Vague

https://scholarworks.boisestate.edu/mfa_artists_2018/1000/thumbnail.jp

The application of ATR-FTIR spectroscopy and multivariate data analysis to study drug crystallisation in the stratum corneum

Drug permeation through the intercellular lipids, which pack around and between corneocytes, may be enhanced by increasing the thermodynamic activity of the active in a formulation. However, this may also result in unwanted drug crystallisation on and in the skin. In this work, we explore the combination of ATR-FTIR spectroscopy and multivariate data analysis to study drug crystallisation in the skin. Ex vivo permeation studies of saturated solutions of diclofenac sodium (DF Na) in two vehicles, propylene glycol (PG) and dimethyl sulphoxide (DMSO), were carried out in porcine ear skin. Tape stripping and ATR-FTIR spectroscopy were conducted simultaneously to collect spectral data as a function of skin depth. Multivariate data analysis was applied to visualise and categorise the spectral data in the region of interest (1700-1500cm(-1)) containing the carboxylate (COO(-)) asymmetric stretching vibrations of DF Na. Spectral data showed the redshifts of the COO(-) asymmetric stretching vibrations for DF Na in the solution compared with solid drug. Similar shifts were evident following application of saturated solutions of DF Na to porcine skin samples. Multivariate data analysis categorised the spectral data based on the spectral differences and drug crystallisation was found to be confined to the upper layers of the skin. This proof-of-concept study highlights the utility of ATR-FTIR spectroscopy in combination with multivariate data analysis as a simple and rapid approach in the investigation of drug deposition in the skin. The approach described here will be extended to the study of other actives for topical application to the skin

Integration and optimization of collusion secure fingerprinting in image watermarking

Estágio realizado na Fraunhofer SIT - e orientado pelo Dr. Huajian Liu e pelo Dr. Marcel SchäferTese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 201

Preemptive mobile code protection using spy agents

This thesis introduces 'spy agents' as a new security paradigm for evaluating trust in remote hosts in mobile code scenarios. In this security paradigm, a spy agent, i.e. a mobile agent which circulates amongst a number of remote hosts, can employ a variety of techniques in order to both appear 'normal' and suggest to a malicious host that it can 'misuse' the agent's data or code without being held accountable. A framework for the operation and deployment of such spy agents is described. Subsequently, a number of aspects of the operation of such agents within this framework are analysed in greater detail. The set of spy agent routes needs to be constructed in a manner that enables hosts to be identified from a set of detectable agent-specific outcomes. The construction of route sets that both reduce the probability of spy agent detection and support identification of the origin of a malicious act is analysed in the context of combinatorial group testing theory. Solutions to the route set design problem are proposed. A number of spy agent application scenarios are introduced and analysed, including: a) the implementation of a mobile code email honeypot system for identifying email privacy infringers, b) the design of sets of agent routes that enable malicious host detection even when hosts collude, and c) the evaluation of the credibility of host classification results in the presence of inconsistent host behaviour. Spy agents can be used in a wide range of applications, and it appears that each application creates challenging new research problems, notably in the design of appropriate agent route sets

The Drowning World : The visual culture of climate change

A challenging question today is how to understand and act on climate change. Previous analyses of the public outreach of the climate sciences have concluded that the urgent communication of climate change is inadequate. It is foremost the invisibility of carbon dioxide and the lack of a tangible relationship between current emissions and future effects that have been seen as the main challenge to visually represent. The Drowning World questions how the communication problem is articulated, and the analysis focuses on the supplementary images that come with this scientific communication, including cover images to reports, backgrounds to diagrams, or graphic design elements. The conclusion is that even if the scientific images might fail to communicate the complexity of the climate issue, the supplementary images, and the way the story of our changing world is told, manage to bring a feeling of change with them. Images of water are especially recurring, as are projects that use immersive environments like virtual reality, and these representations compete for attention in the media noise of modern society, a world that “drowns” the viewers in auditory and visual stimuli. Thus there are many reasons for the title of this thesis – The Drowning World

Democracy and Domination in the Law of Workplace Cooperation: From Bureaucratic to Flexible Production

In May of 1993, President Clinton\u27s Commission for the Future of Worker-Management Relations began its investigation of whether a major overhaul of United States labor law is necessary to encourage high-performance workplaces and labor-management cooperation. Even if its recommendations, due in November 1994, do not yield immediate congressional fruit, the Commission\u27s work is likely to influence the study and politics of labor law reform for some time to come. The Commission is chaired by John Dunlop, the eminent labor-relations specialist and former Secretary of Labor. Its membership includes some of the nation\u27s foremost academic and political proponents of far-reaching labor law reform. The Commission\u27s Chief Counsel is Harvard Law School\u27s Paul Weiler, who, over the last decade, has built the most formidable edifice of comprehensive reform proposals within the legal academic community. The appointment of the Dunlop Commission registers several seismic changes in the topography of labor relations in recent decades. First, the percentage of private-sector employees in unionized workplaces has declined from nearly 37 percent in 1953 to less than 12 percent today. The resulting representation gap in workplace governance is a salient policy concern for philosophic proponents of industrial democracy and for economic supporters of those welfare-enhancing workplace arrangements that require collective action by employees. Concurrent with the fall of organized labor, the annual growth in labor productivity slowed from a median of three percent in the post-World War II boom years to little more than one percent since the late 1960s. This climacteric coincided with an intensification of global economic competition and volatility in product and capital markets. These years also saw the emergence, led by Japan, of lean production systems that seem to break with the hierarchical mass-production model at the core of United States industry. Many variants of the emergent organizations are based on principles of flexible collaboration and consultation between employees and managers within the firm and among fluid networks of firms. Their adaptability and delegation of discretion to frontline work teams give such high-performance firms and networks the potential for enhanced productivity, innovation, and employee learning. The United States\u27 regime of adversarial, bureaucratic labor relations seems to fly in the face of the high-performance principles of cooperation and trust. That regime not only imperils labor productivity and participation. Its discouragement of high-skill, high-discretion work processes, together with the fall of organized labor, has helped produce the most unequal distribution of incomes and job opportunities of any advanced industrial country

Micro- and nano-analyses of fracture-filling after flooding on-shore chalk with different IOR fluids

Master's thesis in Petroleum Geosciences EngineeringWater injection into the Ekofisk-reservoir was introduced in 1987 to enhance oil recovery (EOR) dissolution and precipitation by exposing chalk to various brines at reservoir conditions, which further increased deformation of chalk matrix. This deformation affected mechanical properties of the tested samples and is referred to as water weakening of chalk. This thesis has focused on identifying mineral changes and mapping the distribution of precipitated mineral during flooding of samples which have an artificial fracture and will compare hollow cylinder to intact chalk cores. Methods used to achieve a mineralogic map are: • Optical Light Microscopy (OLM) • Light microscopy (LM) • X-ray diffraction (XRD) • Scanning Electron Microscopy (SEM) • Focused Ion Beam (FIB) sample for Transmission Electron Microscopy (TEM) • Mineral Liberation Analyzer (MLA) All cores tested, either intact or hollow and representing all combinations of brine injected, distributed an increased abundance of chlorite. The most sensational observation was the precipitation of magnesite inside the core of the hollow cylinder flooded by MgCl2, and the distinct boundary that this distribution created. Ilmenite was also observed at the same location, while calcite was limited to the matrix itself. Pyrite was not observed in the reference rock, but this was however identified in cores flooded by both MgCl2 and SSW. One non-fractured core injected by SSW experienced clogging after 20 days of flooding. The two samples from this core provided similar composition as the reference rock, hence the reduction of permeability was related to the composition of the brine (SSW) as the comparable core injected with MgCl2 experienced a more dramatic calcite dissolution. This core that clogged also experienced a rapid creep phase and imply that pores could have been clogged solely due to the compression and dissolution of grain to grain contacts during flooding. These results, among others, allows an interpretation that dissolution of original grains and distribution of precipitated minerals is dependent on a variety of processes. The type of brine injected, distribution of porous network and the distance from the inlet are essential parameter which affect the precipitation in the hollow core, so verified in this study. The reactivity and the content of silicate and clay minerals may also influence the process

Identification de personnes par fusion de différentes modalités biométriques

This thesis contributes to the resolution of the problems which are related to the analysis of the biometric data outcome from the iris, the fingerprint and the fusion of these two modalities, for person identification. Thus, after the evaluation of those proposed biometric systems, we have shown that the multimodal biometric system based on iris and fingerprint outperforms both monomodal biometric systems based whatsoever on the iris or on the fingerprint.Cette thèse contribue essentiellement à la résolution des problèmes liés à l'analyse des données biométriques issues de l'iris, de l'empreinte digitale et de la fusion de ces deux modalités pour l'identification de personne. Ainsi, après l'évaluation des trois systèmes biométriques proposés, nous avons prouvé que le système biométrique multimodal basé sur l'iris et l'empreinte digitale est plus performant que les deux systèmes biométriques monomodaux basés que se soit sur l'iris ou sur l'empreinte digitale