High precision swept volume approximation with conservative error bounds

In technical design processes in the automotive industry, digital prototypes rapidly gain importance, because they allow for a detection of design errors in early development stages. The technical design process includes the computation of swept volumes for maintainability analysis and clearance checks. The swept volume is very useful, for example, to identify problem areas where a safety distance might not be kept. With the explicit construction of the swept volume an engineer gets evidence on how the shape of components that come too close have to be modified.rnIn this thesis a concept for the approximation of the outer boundary of a swept volume is developed. For safety reasons, it is essential that the approximation is conservative, i.e., that the swept volume is completely enclosed by the approximation. On the other hand, one wishes to approximate the swept volume as precisely as possible. In this work, we will show, that the one-sided Hausdorff distance is the adequate measure for the error of the approximation, when the intended usage is clearance checks, continuous collision detection and maintainability analysis in CAD. We present two implementations that apply the concept and generate a manifold triangle mesh that approximates the outer boundary of a swept volume. Both algorithms are two-phased: a sweeping phase which generates a conservative voxelization of the swept volume, and the actual mesh generation which is based on restricted Delaunay refinement. This approach ensures a high precision of the approximation while respecting conservativeness.rnThe benchmarks for our test are amongst others real world scenarios that come from the automotive industry.rnFurther, we introduce a method to relate parts of an already computed swept volume boundary to those triangles of the generator, that come closest during the sweep. We use this to verify as well as to colorize meshes resulting from our implementations.

Contributo sperimentale alla ridefinizione della diffusione in parete della camera di prova della galleria del vento Dallara

Joseph Nicolas Cugnot built the first primitive car in 1769 and approximately one hundred year later the first automotive race took place. Thanks to this, for the first time the aerodynamics principles began to be applied to cars. The aerodynamic study of a car is important to improve the performance on the road, or on the track. It purposely enhances the stability in the turns and increases the maximum velocity. However, it is also useful, decrease the fuel consumption, in order to reduce the pollution. Given that cars are a very complex body, the aerodynamic study cannot be conducted following an analytical method, but it is possible, in general, to choose between two different approaches: the numerical or the experimental one. The results of numerical studies depend on the computers’ potential and on the method use to implement the mathematical model. Today, the best way to perform an aerodynamic study is still experimental, which means that in the first phase of the design process the study is performed in a wind tunnel and in later phases directly on track. The automotive wind tunnels are singular mainly due to the test chamber, which typically contains a ground simulation system. The test chamber can have different types of walls: open walls, closed walls, adaptive walls or slotted walls. The best solution is to use the slotted walls because they minimize the interference between the walls and the streamlines, the interaction between the flow and the environment, and also to contain the overall costs. Furthermore, is necessary minimize the boundary layer at the walls, without accelerating the flow, in order to provide the maximum section of homogeneous flow. This thesis aims at redefining the divergent angle of the Dallara Automobili S.P.A. wind tunnel’s walls, in order to improve the overall homogeneity. To perform this study it was necessary to acquire the pressure data of the boundary layer, than it was created the profile of the boundary layer velocity and, to minimize the experimental errors, it was calculated the displacement thickness. The results obtained shows, even if the instrument used to the experiment was not the best one, that the boundary layer thickness could be minor in case of a low diffusion angle. So it is convenient to perform another experiment with a most sensitive instrument to verified what is the better wall configuration.

La strategia BIM a supporto del progetto della sicurezza nel cantiere edile: il caso dell'ospedale di primo soccorso a Lampedusa.

Throughout this research, the whole life cycle of a building will be analyzed, with a special focus on the most common issues that affect the construction sector nowadays, such as safety. In fact, the goal is to enhance the management of the entire construction process in order to reduce the risk of accidents. The contemporary trend is that of researching new tools capable of reducing, or even eliminating, the most common mistakes that usually lead to safety risks. That is one of the main reasons why new technologies and tools have been introduced in the field. The one we will focus on is the so-called BIM: Building Information Modeling. With the term BIM we refer to wider and more complex analysis tool than a simple 3D modeling software. Through BIM technologies we are able to generate a multi-dimension 3D model which contains all the information about the project. This innovative approach aims at a better understanding and control of the project by taking into consideration the entire life cycle and resulting in a faster and more sustainable way of management. Furthermore, BIM software allows for the sharing of all the information among the different aspects of the project and among the different participants involved thus improving the cooperation and communication. In addition, BIM software utilizes smart tools that simulate and visualize the process in advance, thus preventing issues that might not have been taking into consideration during the design process. This leads to higher chances of avoiding risks, delays and cost increases. Using a hospital case study, we will apply this approach for the completion of a safety plan, with a special focus onto the construction phase.

Konzept eines aktiven Pulverinhalators

In dieser Arbeit wird das Konzept eines aktiven Pulverinhalators entwickelt. Im Gegensatz zu einem passiven Pulverinhalator ist bei solch einem Gerät die Abgabe und Dispergierung der Arzneistoffformulierung nicht von einem Inhalationsmanöver abhängig, welches von Patient zu Patient variiert. Solch ein System würde folglich die Zuverlässigkeit und Effizienz der inhalativen Therapie verbessern. Mögliche Anwendungen für einen aktiven Pulverinhalator wären vor allem Indikationen, die die Abgabe hoher Dosen erfordern, wie z.B. in der Therapie mit Antibiotika.rnIn einem Designprozess, der alle aus Kundenwünschen ermittelten Konstruktionsanforderungen sammelt und verschiedene Lösungsansätze vergleicht, wird ein mit Treibgas betriebener atemzugsausgelöster, Mehrfach-Dosis Pulverinhalator als aussichtsreichstes Konzept ermittelt. Dieses Konzept wird in Form von eigens konstruierten Labor-Test-Rigs entwickelt und vor allem hinsichtlich Höhe der Dosierung, Dosiergenauigkeit, und Flussratenabhängigkeit evaluiert. In der Spitze können über 16 mg lungengängiger Dosis erreicht werden, bei im Vergleich zu dem eingesetzten passiven Inhalator mindestens nur halb so großer Streuung. Bei niedrigen Flussraten können immer noch bis zu 80 % der erzielten inhalierbaren Dosis von hohen Flussraten erreicht werden und damit die Ergebnisse des passiven Inhalators deutlich übertreffen.rnTeil der Aufgabe war es, dieses treibgasbetriebene Labor-Test-Rig so zu entwickeln, dass es implementierbar in einen atemzugsausgelösten Mehrfachdosis-Pulverinhalator ist. Dieser treibgasbetriebene, atemzugsausgelöste Mehrfachdosis-Pulverinhalator würde die Kundenwünsche und Konstruktionsanforderungen in sehr hohen Maße erfüllen, so dass hier die Möglichkeit besteht einen Inhalator mit sehr hohem Grad an Patienten-Compliance zu verwirklichen. Durch die Verwendung und Neukombination bereits etablierter Technologien und einen akzeptablen Stückkostenpreis besteht die Möglichkeit den Inhalator tatsächlich zu realisieren und zu vermarkten.

Observations and modeling of the Marginal Ice Zone

Global climate change in recent decades has strongly influenced the Arctic generating pronounced warming accompanied by significant reduction of sea ice in seasonally ice-covered seas and a dramatic increase of open water regions exposed to wind [Stephenson et al., 2011]. By strongly scattering the wave energy, thick multiyear ice prevents swell from penetrating deeply into the Arctic pack ice. However, with the recent changes affecting Arctic sea ice, waves gain more energy from the extended fetch and can therefore penetrate further into the pack ice. Arctic sea ice also appears weaker during melt season, extending the transition zone between thick multi-year ice and the open ocean. This region is called the Marginal Ice Zone (MIZ). In the Arctic, the MIZ is mainly encountered in the marginal seas, such as the Nordic Seas, the Barents Sea, the Beaufort Sea and the Labrador Sea. Formed by numerous blocks of sea ice of various diameters (floes) the MIZ, under certain conditions, allows maritime transportation stimulating dreams of industrial and touristic exploitation of these regions and possibly allowing, in the next future, a maritime connection between the Atlantic and the Pacific. With the increasing human presence in the Arctic, waves pose security and safety issues. As marginal seas are targeted for oil and gas exploitation, understanding and predicting ocean waves and their effects on sea ice become crucial for structure design and for real time safety of operations. The juxtaposition of waves and sea ice represents a risk for personnel and equipment deployed on ice, and may complicate critical operations such as platform evacuations. The risk is difficult to evaluate because there are no long-term observations of waves in ice, swell events are difficult to predict from local conditions, ice breakup can occur on very short time-scales and wave-ice interactions are beyond the scope of current forecasting models [Liu and Mollo-Christensen, 1988,Marko, 2003]. In this thesis, a newly developed Waves in Ice Model (WIM) [Williams et al., 2013a,Williams et al., 2013b] and its related Ocean and Sea Ice model (OSIM) will be used to study the MIZ and the improvements of wave modeling in ice infested waters. The following work has been conducted in collaboration with the Nansen Environmental and Remote Sensing Center and within the SWARP project which aims to extend operational services supporting human activity in the Arctic by including forecast of waves in ice-covered seas, forecast of sea-ice in the presence of waves and remote sensing of both waves and sea ice conditions. The WIM will be included in the downstream forecasting services provided by Copernicus marine environment monitoring service.

The Modified Direct Analysis Method: an Extension of the Direct Analysis Method

The purpose of this research project is to study an innovative method for the stability assessment of structural steel systems, namely the Modified Direct Analysis Method (MDM). This method is intended to simplify an existing design method, the Direct Analysis Method (DM), by assuming a sophisticated second-order elastic structural analysis will be employed that can account for member and system instability, and thereby allow the design process to be reduced to confirming the capacity of member cross-sections. This last check can be easily completed by substituting an effective length of KL = 0 into existing member design equations. This simplification will be particularly useful for structural systems in which it is not clear how to define the member slenderness L/r when the laterally unbraced length L is not apparent, such as arches and the compression chord of an unbraced truss. To study the feasibility and accuracy of this new method, a set of 12 benchmark steel structural systems previously designed and analyzed by former Bucknell graduate student Jose Martinez-Garcia and a single column were modeled and analyzed using the nonlinear structural analysis software MASTAN2. A series of Matlab-based programs were prepared by the author to provide the code checking requirements for investigating the MDM. By comparing MDM and DM results against the more advanced distributed plasticity analysis results, it is concluded that the stability of structural systems can be adequately assessed in most cases using MDM, and that MDM often appears to be a more accurate but less conservative method in assessing stability.

Besonderheiten bei der Auslegung und Gestaltung lasergesinterter Bauteile

Mit der Entwicklung der losgrößenunabhängigen, additiven Fertigungsverfahren eröffnen sich vollkommen neue Wege zur Realisierung von komplexen Integralbauteilen bei niedrigen Stückzahlen. Bei der Bauteilgestaltung müssen (verglichen mit traditionellen Herstellverfahren, beispielsweise Spritzgießen) weniger Fertigungsrestriktionen beachtet werden. Dennoch ist die Gestaltungsfreiheit nicht unbegrenzt. In diesem Beitrag werden basierend auf dem Gedanken des Fertigungsgerechten Konstruierens Möglichkeiten und Herausforderungen bei der Gestaltung von additiv gefertigten Bauteilen herausgestellt. Darauf aufbauend werden Potenziale aufgezeigt, wie Produktentwickler in Zukunft bei der Auslegung und Gestaltung solcher Produkte unterstützt werden können.

Intelligent Virtual Patients for Training Clinical Skills

The article presents the design process of intelligent virtual human patients that are used for the enhancement of clinical skills. The description covers the development from conceptualization and character creation to technical components and the application in clinical research and training. The aim is to create believable social interactions with virtual agents that help the clinician to develop skills in symptom and ability assessment, diagnosis, interview techniques and interpersonal communication. The virtual patient fulfills the requirements of a standardized patient producing consistent, reliable and valid interactions in portraying symptoms and behaviour related to a specific clinical condition.

Virtual Reality as a Support Tool for Ergonomic-Style Convergence

The competitive industrial context compels companies to speed-up every new product design. In order to keep designing products that meet the needs of the end user, a human centered concurrent product design methodology has been proposed. Its setting up is complicated by the difficulties of collaboration between experts involved inthe design process. In order to ease this collaboration, we propose the use of virtual reality as an intermediate design representation in the form of light and specialized immersive convergence support applications. In this paper, we present the As Soon As Possible (ASAP) methodology making possible the development of these tools while ensuring their usefulness and usability. The relevance oft his approach is validated by an industrial use case through the design of an ergonomic-style convergence support tool.

The transformation of the Rijksmuseum Amsterdam

This article focuses on the design process for the transformation of the Rijksmuseum Amsterdam (1885, by P.J.H. Cuypers), with special attention for the evolution of the design by Cruz y Ortiz arquitectos and the associated history of ideas. How did opinions on the intervention evolve from the concept for a masterplan in 1996 to the realized project? To what extent were all those diverse ambitions regarding the city, the monument and the museum realized? What was the role of the designers, not only referring to Cruz y Ortiz, but also to Van Hoogevest Architecten (restoration) and Wilmotte & Associés (interior)? How did the design evolve in a complex and ambitious context involving a great many interested parties, and what effect did this have on the design process from the first sketches to the ultimately realized renovation?

Community participation in health services

This study critically analyzes and synthesizes community participation (CP) theory across disciplines, defining and beginning to map out the elements of CP according to a preliminary framework of structure, process, intermediate outcomes, and ultimate outcomes. The first study component sought to determine the impact of Sight N' Soul, a CP project utilizing neighborhood health workers (NHWs), on appointment missing in an indigent urban African-American population. It found that persons entering the vision care system through contact with an NEW were about a third less likely to miss an appointment than those persons entering the system through some other avenue. While theory in this area remains too poorly developed to hypothesize causal relationships between structure, process, and outcomes, a summary of the elements of Sight N' Soul's structure and process both developed the preliminary framework and serves as a first step to mapping these relationships. The second component of the study uncovered the elements of structure and process that may contribute to a sustained egalitarian partnership between community people and professionals, a CP program called Project HEAL. Elements of Project HEAL's structure and process included a shared belief in the program; spirituality; contribution, ownership, and reciprocation; a feeling of family; making it together; honesty, trust, and openness about conflict; the inevitability of uncertainty and change; and the guiding interactional principles of respect; love, care, and compassion; and personal responsibility. The third component analyzed the existing literature, identifying and addressing gaps and inconsistencies and highlighting areas needing more highly developed ethical analysis. Focal issues include the political, economic, and historical context of CP; the power of naming; the issue of purpose; the nature of community; the power to muster and allocate resources; and the need to move to a systems view of health and well-being, expanding our understanding of the universe of potential outcomes of CP, including iatrogenic outcomes. Intermediate outcomes might include change in community, program, and individual capacity, as well as improved health care delivery. Ultimate outcomes include increased positive interdependencies and opportunities for contribution; improved mental, physical, and spiritual health; increased social justice; and decreased exploitation. ^

Usability and Acceptability of ASSESS MS: Assessment of Motor Dysfunction in Multiple Sclerosis Using Depth-Sensing Computer Vision

Background: Sensor-based recordings of human movements are becoming increasingly important for the assessment of motor symptoms in neurological disorders beyond rehabilitative purposes. ASSESS MS is a movement recording and analysis system being developed to automate the classification of motor dysfunction in patients with multiple sclerosis (MS) using depth-sensing computer vision. It aims to provide a more consistent and finer-grained measurement of motor dysfunction than currently possible. Objective: To test the usability and acceptability of ASSESS MS with health professionals and patients with MS. Methods: A prospective, mixed-methods study was carried out at 3 centers. After a 1-hour training session, a convenience sample of 12 health professionals (6 neurologists and 6 nurses) used ASSESS MS to capture recordings of standardized movements performed by 51 volunteer patients. Metrics for effectiveness, efficiency, and acceptability were defined and used to analyze data captured by ASSESS MS, video recordings of each examination, feedback questionnaires, and follow-up interviews. Results: All health professionals were able to complete recordings using ASSESS MS, achieving high levels of standardization on 3 of 4 metrics (movement performance, lateral positioning, and clear camera view but not distance positioning). Results were unaffected by patients’ level of physical or cognitive disability. ASSESS MS was perceived as easy to use by both patients and health professionals with high scores on the Likert-scale questions and positive interview commentary. ASSESS MS was highly acceptable to patients on all dimensions considered, including attitudes to future use, interaction (with health professionals), and overall perceptions of ASSESS MS. Health professionals also accepted ASSESS MS, but with greater ambivalence arising from the need to alter patient interaction styles. There was little variation in results across participating centers, and no differences between neurologists and nurses. Conclusions: In typical clinical settings, ASSESS MS is usable and acceptable to both patients and health professionals, generating data of a quality suitable for clinical analysis. An iterative design process appears to have been successful in accounting for factors that permit ASSESS MS to be used by a range of health professionals in new settings with minimal training. The study shows the potential of shifting ubiquitous sensing technologies from research into the clinic through a design approach that gives appropriate attention to the clinic environment.

Perinatal mortality and quality of care at the National Institute of Perinatology: A 3-year analysis

Quality of medical care has been indirectly assessed through the collection of negative outcomes. A preventable death is one that could have been avoided if optimum care had been offered. The general objective of the present project was to analyze the perinatal mortality at the National Institute of Perinatology (located in Mexico City) by social, biological and some available components of quality of care such as avoidability, provider responsibility, and structure and process deficiencies in the delivery of medical care. A Perinatal Mortality Committee data base was utilized. The study population consisted of all singleton perinatal deaths occurring between January 1, 1988 and June 30, 1991 (n = 522). A proportionate study was designed.^ The population studied mostly corresponded to married young adult mothers, who were residents of urban areas, with an educational level of junior high school or more, two to three pregnancies, and intermediate prenatal care. The mean gestational age at birth was 33.4 $\pm$ 3.9 completed weeks and the mean birthweight at birth was 1,791.9 $\pm$ 853.1 grams.^ Thirty-five percent of perinatal deaths were categorized as avoidable. Postnatal infection and premature rupture of membranes were the most frequent primary causes of avoidable perinatal death. The avoidable perinatal mortality rate was 8.7 per 1000 and significantly declined during the study period (p $<$.05). Preventable perinatal mortality aggregated data suggested that at least part of the mortality decline for amenable conditions was due to better medical care.^ Structure deficiencies were present in 35% of avoidable deaths and process deficiencies were present in 79%. Structure deficiencies remained constant over time. Process deficiencies consisted of diagnosis failures (45.8%) and treatment failures (87.3%), they also remained constant through the years. Party responsibility was as follows: Obstetric (35.4%), pediatric (41.4%), institutional (26.5%), and patient (6.6%). Obstetric responsibility significantly increased during the study period (p $<$.05). Pediatric responsibility declined only for newborns less than 1500 g (p $<$.05). Institutional responsibility remained constant.^ Process deficiencies increased the risk for an avoidable death eightfold (confidence interval 1.7-41.4, p $<$.01) and provider responsibility ninety-fivefold (confidence interval 14.8-612.1, p $<$.001), after adjustment for several confounding variables. Perinatal mortality due to prematurity, barotrauma and nosocomial infection, was highly preventable, but not that due to transpartum asphyxia. Once specific deficiencies in the quality of care have been identified, quality assurance actions should begin. ^

Efficiency from pharmacy inventory technology: A means to improving quality in non-profit hospitals

Hospitals, like all organizations, have both a mission and a finite supply of resources with which to accomplish that mission. Because the inventory of therapeutic drugs is among the more expensive resources needed by a hospital to achieve its mission, a conceptual model of structure plus process equals outcome posits that adequate emphasis should be placed on optimization of the organization's investment in this important structural resource to provide highest quality outcomes. Therefore emphasis should be placed on the optimization of pharmacy inventory because lowering the financial investment in drug inventory and associated costs increases productive efficiency, a key element of quality. ^ In this study, a post-intervention analysis of a hospital pharmacy inventory management technology implementation at The University of Texas M.D. Anderson Cancer Center was conducted to determine if an intervention which reduced a hospital's financial investment in pharmaceutical inventory provided an opportunity to incrementally optimize the organization's mix of structural resources thereby improving quality of care. The results suggest that hospital pharmacies currently lacking technology to support automated purchasing logistics and perpetual, real-time inventory management for drugs may achieve measurable benefits from the careful implementation of such technology, enabling the hospital to lower its investment in on-hand inventory and, potentially, to reduce overall purchasing expenditures. ^ The importance of these savings to the hospital and potentially to the patient should not be underestimated for their ability to generate funding for previously unfunded public health programs or in their ability to provide financial relief to patients in the form of lower drug costs given the current climate of escalating healthcare costs and tightening reimbursements.^

Distribution of polycyclic aromatic hydrocarbons in eolian and eolian-deluvial sediments from the North Iceland

This work considers results of a study of Holocene cover sediments in Iceland. They are largely composed of wind-transported palagonitized hyaloclastite particles and coeval horizons of acid and basic tephras. It is established that polyciclic aromatic hydrocarbons (PAH) are released from basaltic glass in natural environments only in case of intense physicochemical alteration and destruction of its structure. This process does not influence PAH composition and their quantitative proportions. No new PAH formed during several thousands of years in Holocene section. Hydrocarbons are transferred from fixed state in basaltic glass into free state in palagonites practically without any changes. PAH were mainly redeposited by winds, derived together with palagonite from weathered hyaloclastites, and precipitated from atmosphere with tephra during eruptions.