863 resultados para set based design


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This report presents the development of a Stochastic Knock Detection (SKD) method for combustion knock detection in a spark-ignition engine using a model based design approach. Knock Signal Simulator (KSS) was developed as the plant model for the engine. The KSS as the plant model for the engine generates cycle-to-cycle accelerometer knock intensities following a stochastic approach with intensities that are generated using a Monte Carlo method from a lognormal distribution whose parameters have been predetermined from engine tests and dependent upon spark-timing, engine speed and load. The lognormal distribution has been shown to be a good approximation to the distribution of measured knock intensities over a range of engine conditions and spark-timings for multiple engines in previous studies. The SKD method is implemented in Knock Detection Module (KDM) which processes the knock intensities generated by KSS with a stochastic distribution estimation algorithm and outputs estimates of high and low knock intensity levels which characterize knock and reference level respectively. These estimates are then used to determine a knock factor which provides quantitative measure of knock level and can be used as a feedback signal to control engine knock. The knock factor is analyzed and compared with a traditional knock detection method to detect engine knock under various engine operating conditions. To verify the effectiveness of the SKD method, a knock controller was also developed and tested in a model-in-loop (MIL) system. The objective of the knock controller is to allow the engine to operate as close as possible to its border-line spark-timing without significant engine knock. The controller parameters were tuned to minimize the cycle-to-cycle variation in spark timing and the settling time of the controller in responding to step increase in spark advance resulting in the onset of engine knock. The simulation results showed that the combined system can be used adequately to model engine knock and evaluated knock control strategies for a wide range of engine operating conditions.

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Complex human diseases are a major challenge for biological research. The goal of my research is to develop effective methods for biostatistics in order to create more opportunities for the prevention and cure of human diseases. This dissertation proposes statistical technologies that have the ability of being adapted to sequencing data in family-based designs, and that account for joint effects as well as gene-gene and gene-environment interactions in the GWA studies. The framework includes statistical methods for rare and common variant association studies. Although next-generation DNA sequencing technologies have made rare variant association studies feasible, the development of powerful statistical methods for rare variant association studies is still underway. Chapter 2 demonstrates two adaptive weighting methods for rare variant association studies based on family data for quantitative traits. The results show that both proposed methods are robust to population stratification, robust to the direction and magnitude of the effects of causal variants, and more powerful than the methods using weights suggested by Madsen and Browning [2009]. In Chapter 3, I extended the previously proposed test for Testing the effect of an Optimally Weighted combination of variants (TOW) [Sha et al., 2012] for unrelated individuals to TOW &ndash F, TOW for Family &ndash based design. Simulation results show that TOW &ndash F can control for population stratification in wide range of population structures including spatially structured populations, is robust to the directions of effect of causal variants, and is relatively robust to percentage of neutral variants. In GWA studies, this dissertation consists of a two &ndash locus joint effect analysis and a two-stage approach accounting for gene &ndash gene and gene &ndash environment interaction. Chapter 4 proposes a novel two &ndash stage approach, which is promising to identify joint effects, especially for monotonic models. The proposed approach outperforms a single &ndash marker method and a regular two &ndash stage analysis based on the two &ndash locus genotypic test. In Chapter 5, I proposed a gene &ndash based two &ndash stage approach to identify gene &ndash gene and gene &ndash environment interactions in GWA studies which can include rare variants. The two &ndash stage approach is applied to the GAW 17 dataset to identify the interaction between KDR gene and smoking status.

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Ureides are compounds, which essentially incorporate urea as a substructural component either in open or cyclic form. Ureido derivatives are one of the oldest classes of bioactives, widely used as antiinfective agents. Several of these compounds, including aminoquinuride, aminocarbalide, imidurea, cloflucarban, nitrofurazone, urosulfan, viomycin are used in clinical situations. One of the ureides, the triclocarban is compulsorily used as antibacterial agent in cleansing and disinfecting solutions in hospital, household, cosmetics, toys, textile and plastics. It disables the activity of ENR, an enzyme vital for building the cell wall of the bacteria and fungus. Besides, the ureido-penicillins in clinical use there have been several ureido-lactam derivatives which have been reported to exhibit significant antibacterial activity. A urea containing dipeptide TAN-1057A isolated from Flexibacter spp. has potent bioactivity against MRSA. The metal complexes of sulphonyl ureido derivatives are effective antifungal agents by inhibiting the activity of phosphomannose isomerase, a key enzyme in the biosynthesis of yeast cell walls. There have been number of ureides including the cyclic ureas which are potent HIV protease inhibitors and display significant anti-HIV activity. The urea derivative, merimepodip that has been derived using structure based design, is potent inhibitor of IMPDH and is active against Hepatitis-C infection. This review will primarily focus on the significant work reported for this class of compounds including design, synthesis and biological activity.

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The past few years, multimodal interaction has been gaining importance in virtual environments. Although multimodality renders interacting with an environment more natural and intuitive, the development cycle of such an application is often long and expensive. In our overall field of research, we investigate how modelbased design can facilitate the development process by designing environments through the use of highlevel diagrams. In this scope, we present ‘NiMMiT’, a graphical notation for expressing and evaluating multimodal user interaction; we elaborate on the NiMMiT primitives and demonstrate its use by means of a comprehensive example.

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Software architecture consists of a set of design choices that can be partially expressed in form of rules that the implementation must conform to. Architectural rules are intended to ensure properties that fulfill fundamental non-functional requirements. Verifying architectural rules is often a non- trivial activity: available tools are often not very usable and support only a narrow subset of the rules that are commonly specified by practitioners. In this paper we present a new highly-readable declarative language for specifying architectural rules. With our approach, users can specify a wide variety of rules using a single uniform notation. Rules can get tested by third-party tools by conforming to pre-defined specification templates. Practitioners can take advantage of the capabilities of a growing number of testing tools without dealing with them directly.

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Do apprenticeships convey mainly general or also firm- and occupation-specific human capital? Specific human capital may allow for specialization gains, but may also lead to allocative inefficiency due to mobility barriers. We analyse the case of Switzerland, which combines a comprehensive, high-quality apprenticeship system with a lightly regulated labour market. To assess human capital transferability after standardized firm-based apprenticeship training, we analyse inter-firm and occupational mobility and their effects on post-training wages. Using a longitudinal data set based on the PISA 2000 survey, we find high inter-firm and low occupational mobility within one year after graduation. Accounting for endogenous changes, we find a negative effect of occupation changes on wages, but no significant wage effect for firm changes. This indicates that occupation-specific human capital is an important component of apprenticeship training and that skills are highly transferable within an occupational field.

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In-situ proton-microprobe analyses are presented for glasses, plagioclases, pyroxenes, olivines, and spinels in eleven samples from Sites 834-836, 839, and 841 (vitrophyric rhyolite), plus a Tongan dacite. Elements analyzed are Mn, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Pb, and Sn (in spinels only). The data are used to calculate two sets of partition coefficients, one set based on the ratio of element in mineral/element in coexisting glass. The second set of coefficients, thought to be more robust, is corrected by application of the Rayleigh fractionation equations, which requires additional use of modal data. Data are presented for phenocryst core-rim phases and microphenocryst-groundmass phases from a few samples. Comparison with published coefficients reveals an overall consistency with those presented here, but with some notable anomalies. Examples are relatively high Zr values for pyroxenes and abnormally low Mn values in olivines and clinopyroxenes from Site 839 lavas. Some anomalies may reflect kinetic effects, but interpretation of the coefficients is complicated, especially in olivines from Sites 836 and 839, by possible crystal-liquid disequilibrium resulting from mixing processes.

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Postcruise X-ray diffraction (XRD) data for 95 whole-rock samples from Holes 1188A, 1188F, 1189A, and 1189B are presented. The samples represent alteration types recovered during Leg 193. The data set is incorporated into the shipboard XRD data set. Based on the newly obtained XRD data, distribution of alteration phases were redrawn for Ocean Drilling Program Sites 1188 and 1189.

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The mid-Piacenzian (MP) warm period (3.264-3.025 Ma) has been identified as the most recent time in geologic history during which mean global surface temperatures were considerably warmer than today for a sustained period. This interval has therefore been proposed as a potential (albeit imperfect) analog for future climate change and as such, has received much scientific attention over the past two decades. Central to this research effort is the Pliocene Research, Interpretation, and Synoptic Mapping (PRISM) project, an iterative paleoenvironmental reconstruction of the MP focused on increasing our understanding of warm-period climate forcings, dynamics, and feedbacks by providing three-dimensional data sets for general circulation models. A mainstay of the PRISM project has been the development of a global sea surface temperature (SST) data set based primarily upon quantitative analyses of planktic foraminifer assemblages, supplemented with geochemical SST estimates wherever possible. In order to improve spatial coverage of the PRISM faunal data set in the low and mid-latitude North Atlantic, this study provides a description of the MP planktic foraminifer assemblage from five Ocean Drilling Program sites (951, 958, 1006, 1062, and 1063) in the subtropical gyre, a region critical to Atlantic Ocean circulation and tropical heat advection. Assemblages from each core provide evidence for a temperature- and circulation-driven 5-10° northward displacement of MP faunal provinces, as well as regional shifts in planktic foraminifer populations linked to species ecology and interactions. General biogeographic trends also indicate that, relative to modern conditions, gyre circulation was stronger (particularly the Gulf Stream, North Atlantic Current, and North Equatorial Current) and meridionally broader. A comparison of mid-Piacenzian and modern North Atlantic planktic foraminifer assemblages suggests that low latitude western boundary currents were less than 1 °C warmer while eastern boundary currents were ~1-2 °C warmer, supporting the hypothesis of enhanced northward heat advection along western boundary currents and warming of high latitude Northeast Atlantic source regions for the Canary Current. These findings are consistent with a model of reduced meridional SST gradients, with little-to-no low latitude warming, and more vigorous ocean circulation. Results therefore support the theory that enhanced meridional overturn circulation and associated northward heat advection made an important contribution, in conjunction with elevated atmospheric CO2 concentrations, to the 2-3 °C global surface temperature increase (relative to today) and strong polar amplification of SST warmth during the MP warm period.

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In this talk we address a proposal concerning a methodology for extracting universal, domain neutral, architectural design patterns from the analysis of biological cognition. This will render a set of design principles and design patterns oriented towards the construction of better machines. Bio- inspiration cannot be a one step process if we we are going to to build robust, dependable autonomous agents; we must build solid theories first, departing from natural systems, and supporting our designs of artificial ones.

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La acción del dibujar intenta presentarse en este texto como lenguaje mudo, práctica común general y práctica común en el campo arquitectónico en concreto; y también como acción, apertura, exploración (no representación) en el estado naciente del proyecto. La tesis se presenta como un estudio basado en la experiencia directa, la observación in situ (Practice Based Design Doctórate) intentando reflexionar no desde sus productos alcanzados al dibujar, sino desde la propia acción, enfatizando la dinamicidad del cuerpo como productor de gestos dinámicos. El trabajo busca describir la acción del trazar como apertura, exploración (no representación) en el estado naciente del proyecto. Es el cruce entre la acción experienciada y el pensamiento crítico respecto al hacer con aproximaciones a la artesanía (Sennett, 2010), al placer del dibujar (Nancy, 2013) y la aventura de conformar (Badiou, 2006). La experiencia en el dibujar que este estudio recoge es la desarrollada por la autora en el contexto pedagógico del D.I.G.A. de la E.T.S.A. de Madrid en concreto en las asignaturas “Dibujo Avanzado e Interpretación Gráfica (DAII) I y II” y “Dibujo del Natural” ambas impartidas por el profesor Antonio Verd Herrero y en la participación en los trabajos del Grupo de Investigación y de Innovación Educativa denominado: “Hypermedia” dirigidos por el profesor Javier Seguí, en el periodo que va del año 2007 a la actualidad. La colección de acontecimientos que surgió de esta experiencia y se formó de aproximaciones sucesivas presenta algunos rasgos característicos de la acción del dibujar. Los acontecimientos abordan la acción del dibujar desde una experiencia muda, un tipo de lenguaje, escritura y comunicación común, intercultural pero a la vez impersonal, desde su relación con la escritura, la palabra, el movimiento, el gesto y su imagen. El dibujar se presenta como modo de exploración en la investigación proyectual basada en la arbitrariedad que requiere voluntad, compromiso, ir en contra para participar en cualquier transformación de los límites (físicos, nacionales, sociales, de género, religión, sentido). El dibujar no representativo se presenta como técnica imaginaria radical, “terapia” configural con capacidad para la experimentación con uno mismo (Sloderdijk, 2003), un modo de comunicación intercultural que, sin embargo, siempre recurre al lenguaje verbal, leída e interpretada para cobrar sentido. ABSTRACT The action of drawing is intended to be presented in this text as a mute language, a common practice in general and a common practice in the field of architecture specifically; and also as an action, opening, exploration (not representation) at the birth stage of a project. The thesis forms a study based on a direct observation in an in situ experience (Practice Based Design Doctórate), which intends to reflect not on the products produced by drawing, but on the action itself, emphasizing on the dynamics of the body as a generator of dynamic gestures. The work is the intersection of experienced action and critical thinking related with the making with an approach to a path on craftsmanship (Sennett, 2010), the pleasure in drawing (Nancy, 2013) and the adventure of compromise/ conciliation (Badiou, 2006). The experience in drawing was collected and developed for this study by the author in the context of D.I.G.A. at the E.T.S.A. of Madrid and in particular at the courses of “Advanced Drawing and Graphic Interpretation” (DAII) I y II” and “Life drawing”, together with the active participation and the work of the investigation and Innovation Educational Group “Hypermedia”, coordinated by professor Javier Seguí, during the period starting the year 2007 until the present (2013). The collection of the events derives from a process of successive attempts to approach some characteristic aspects of the action of drawing. The events approach the action of drawing as a mute experience, a kind of language, common communication, writing, gesture and image. Drawing is presented as a way of exploration for a project's investigation, based on arbitrarily and on the asking “what if”. At the same time this process requires will, compromise, opposition in order to participate in a transformation of any kind of limits (physical, national, social, genre, religion, sense). This thesis aims to present non-representative drawing as a radical imaginary technique, a configurational ‘therapy’ with the capacity to experiment with oneself (Sloderdijk, 2003). It can also be considered as a way of intercultural communication which always uses the verbal, readable and interpreted language in order to charge sense.

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The paper focuses on the analysis of radial-gated spillways, which is carried out by the solution of a numerical model based on the finite element method (FEM). The Oliana Dam is considered as a case study and the discharge capacity is predicted both by the application of a level-set-based free-surface solver and by the use of traditional empirical formulations. The results of the analysis are then used for training an artificial neural network to allow real-time predictions of the discharge in any situation of energy head and gate opening within the operation range of the reservoir. The comparison of the results obtained with the different methods shows that numerical models such as the FEM can be useful as a predictive tool for the analysis of the hydraulic performance of radial-gated spillways.

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Modern sensor technologies and simulators applied to large and complex dynamic systems (such as road traffic networks, sets of river channels, etc.) produce large amounts of behavior data that are difficult for users to interpret and analyze. Software tools that generate presentations combining text and graphics can help users understand this data. In this paper we describe the results of our research on automatic multimedia presentation generation (including text, graphics, maps, images, etc.) for interactive exploration of behavior datasets. We designed a novel user interface that combines automatically generated text and graphical resources. We describe the general knowledge-based design of our presentation generation tool. We also present applications that we developed to validate the method, and a comparison with related work.

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Optical communications receivers using wavelet signals processing is proposed in this paper for dense wavelength-division multiplexed (DWDM) systems and modal-division multiplexed (MDM) transmissions. The optical signal-to-noise ratio (OSNR) required to demodulate polarization-division multiplexed quadrature phase shift keying (PDM-QPSK) modulation format is alleviated with the wavelet denoising process. This procedure improves the bit error rate (BER) performance and increasing the transmission distance in DWDM systems. Additionally, the wavelet-based design relies on signal decomposition using time-limited basis functions allowing to reduce the computational cost in Digital-Signal-Processing (DSP) module. Attending to MDM systems, a new scheme of encoding data bits based on wavelets is presented to minimize the mode coupling in few-mode (FWF) and multimode fibers (MMF). The Shifted Prolate Wave Spheroidal (SPWS) functions are proposed to reduce the modal interference.

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Passive energy dissipation devices are increasingly implemented in frame structures to improve their performance under seismic loading. Most guidelines for designing this type of system retain the requirements applicable to frames without dampers, and this hinders taking full advantage of the benefits of implementing dampers. Further, assessing the extent of damage suffered by the frame and by the dampers for different levels of seismic hazard is of paramount importance in the framework of performance-based design. This paper presents an experimental investigation whose objectives are to provide empirical data on the response of reinforced concrete (RC) frames equipped with hysteretic dampers (dynamic response and damage) and to evaluate the need for the frame to form a strong column-weak beam mechanism and dissipate large amounts of plastic strain energy. To this end, shake-table tests were conducted on a 2/5-scale RC frame with hysteretic dampers. The frame was designed only for gravitational loads. The dampers provided lateral strength and stiffness, respectively, three and 12 times greater than those of the frame. The test structure was subjected to a sequence of seismic simulations that represented different levels of seismic hazard. The RC frame showed a performance level of "immediate occupancy", with maximum rotation demands below 20% of the ultimate capacity. The dampers dissipated most of the energy input by the earthquake. It is shown that combining hysteretic dampers with flexible reinforced concrete frames leads to structures with improved seismic performance and that requirements of conventional RC frames (without dampers) can be relieved.