Yes / A recent development of the Molecular Stress Function constitutive model, the Hierarchical Multi-Mode Molecular Stress Function (HMMSF) model has been shown to fit a large range of rheometrical data with accuracy, for a large range of polymer melts. We develop a 3D simulation of the HMMSF model and compare it to experimental data for the flow of Lupolen 1840H LDPE through an abrupt 3D contraction flow. We believe this to be the first finite element implementation of the HMMSF model. It is shown that the model gives a striking agreement with experimental vortex opening angles, with very good agreement to full-field birefringence measurements, over a wide range of flow rates. A method to give fully-developed inlet boundary conditions is implemented (in place of using parabolic inlet boundary conditions), which gives a significantly improved match to birefringence measurements in the inlet area, and in low stress areas downstream from the inlet. Alternative constitutive model parameters are assessed following the principle that extensional rheometer data actually provides a ‘lower bound’ for peak extensional viscosity. It is shown that the model robustly maintains an accurate fit to vortex opening angle and full-field birefringence data, provided that both adjustable parameters are kept such that both shear and extensional data are well fitted.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper describes a telemetry system developed for the EA-18G Flight Test program. The program requires transmission of a number of data streams, in IRIG-106 Chapter 4 PCM, Chapter 8 Mux-All 1553, Ethernet, and Fibre Channel formats. The initial requested data rate was in excess of 30 Mbits/sec. The telemetry system must operate at a range up to about 120 miles, at several test ranges, and with several different aircraft maneuvering configurations. To achieve these requirements, the Flight Test Instrumentation group at Boeing Integrated Defense Systems in Saint Louis, developed a telemetry system in conjunction with industry partners and test range customers. The system transmits two telemetry streams with a total aggregate rate on the order of 20 Mbits/sec. Each telemetry stream consists of up to four PCM streams, combined in a Teletronics Technology Corporation (TTC) Miniature Adaptable Real-Time Multiplexer Unit (MARM) data combiner. It uses Nova Engineering multi-mode transmitters capable of transmitting PCM-FM or Shaped Offset Quadrature Phase Shift Keying (SOQPSK). The transmitter also provides Turbo-Product Code (TPC) Forward Error Correction (FEC) to enhance range and improve link performance. Data collection units purchased from outside vendors or developed by Saint Louis Flight Test Instrumentation, translate Ethernet and Fibre Channel information into traditional PCM streams. A Boeing Flight Test Instrumentation developed control system provides flexible selection of streams to be combined into each telemetry stream, and functional control of antenna selection and transmitter operation.

An experimental study of the effect of initial conditions on the development of Rayleigh Taylor Instabilities (RTI) at low Atwood numbers (order of 10-4) was performed in the water channel facility at TAMU. Initial conditions of the flow were generated using a controllable, highly reliable Servo motor. The uniqueness of the study is the system’s capability of generating the required initial conditions precisely as compared to the previous endeavors. Backlit photography was used for imaging and ensemble averaging of the images was performed to study mixing width characteristics in different regimes of evolution of Rayleigh-Taylor Instability (RTI). High-speed imaging of the flows was performed to provide insights into the growth of bubble and spikes in the linear and non-linear regime of instability development. RTI are observed in astrophysics, geophysics and in many instances in nature. The vital role of RTI in the feasibility and efficiency of the Inertial Confinement Fusion (ICF) experiment warrants a comprehensive study of the effect of mixing characteristics of RTI and its dependence on defining parameters. With this broader objective in perspective, the objectives of this present investigation were mainly threefold: First was the validation of the novel setup of the Water channel system. Towards this objective, validation of Servo motor, splitter plate thickness effects, density and temperature measurements and single-mode experiments were performed. The second objective was to study the mixing and growth characteristics of binary and multi-mode initial perturbations seeking an explanation of behavior of the resultant flow structures by performing the first ever set of such highly controlled experiments. The first-ever set of experiments with highly controlled multi-mode initial conditions was performed. The final objective of this study was to measure and compare the bubble and spike velocities with single-mode initial conditions with existing analytical models. The data derived from these experiments would qualitatively and quantitatively enhance the understanding of dependence of mixing width on parametric initial conditions. The knowledge would contribute towards a generalized theory for RTI mixing with specified dependence on various parameters, which has a wide range of applications. The system setup was validated to provide a reliable platform for the novel multi-modal experiments to be performed in the future. It was observed that the ensemble averaged mixing width of the binary system does not vary significantly with the phase-difference between the modes of a binary mode initial condition experiment, whereas it varies with the amplitudes of the component modes. In the exponential and non-linear regimes of evolution, growth rates of multi-mode perturbations were found to be higher than the component modes, whereas saturation growth rates correspond to the dominant wavelength. Quadratic saturation growth rate constants, alpha were found to be about 0.07 ± 0.01 for binary and multi modes whereas single-mode data measured alpha about 0.06 ± 0.01. High-speed imaging was performed to measure bubble and spike amplitudes to obtain velocities and growth rates. It was concluded that higher temporal and spatial resolution was required for accurate measurement. The knowledge gained from the above study will facilitate a better understanding of the physics underlying Rayleigh-Taylor instability. The results of this study will also help validating numerical models for simulation of this instability, thereby providing predictive capability for more complex configurations.

In this thesis, novel designs for adaptive power amplifiers, capable of maintaining excellent performance at dissimilar signal parameters, are presented. These designs result in electronically reconfigurable, single-ended and Doherty power amplifiers (DPA) that efficiently sustain functionality at different driving signal levels, highly varying time domain characteristics and wide-spread frequency bands. The foregoing three contexts represent those dictated by the diverse standards of modern communication systems. Firstly, two prototypes for a harmonically-tuned reconfigurable matching network using discrete radio frequency (RF) microelectromechanical systems (MEMS) switches and semiconductor varactors will be introduced. Following that is an explanation of how the varactor-based matching network was used to develop a high performance reconfigurable Class F-1 power amplifier. Afterwards, a systematic design procedure for realizing an electronically reconfigurable DPA capable of operating at arbitrary centre frequencies, average power levels and back-off efficiency enhancement power ranges is presented. Complete sets of closed-form equations are outlined which were used to build tunable matching networks that compensate for the deviation of the Doherty distributed elements under the desired deployment scenarios. Off-the-shelf RF MEMS switches are used to realize the reconfigurability of the adaptive Doherty amplifiers. Finally, based on the derived closed-form equations, a tri-band, monolithically integrated DPA was realized using the Canadian Photonics Fabrication Centre (CPFC??) GaN500 monolithic microwave integrated circuit (MMIC) process. Successful integration of high power, high performance RF MEMS switches within the MMIC process paved the way for the realization of the frequency-agile, integrated version of the adaptive Doherty amplifier.

Στην παρούσα διπλωματική εργασία θα μελετήσουμε τις διαδικασίες της κρυπτογράφησης και της αποκρυπτογράφησης. Θα αναφερθούμε στους λόγους που τις έκαναν δημοφιλείς σε πολλά πεδία εφαρμογής (μαθηματικά, εμπόριο, στρατός κ.α). Ιδιαίτερη αναφορά θα γίνει στους κρυπτογραφικούς αλγορίθμους SHA-256 και SHA-512. Θα μελετήσουμε τη δομή τους και τον τρόπο λειτουργίας τους. Στη συνέχεια θα μελετήσουμε πως μπορούμε σε ένα κύκλωμα να συνδυάσουμε τόσο τη λειτουργία του αλγορίθμου SHA-256, όσο και του SHA-512. Το καινούργιο αυτό κύκλωμα καλείται multi-mode. Τέλος, θα χρησιμοποιήσουμε το Modelsim για την εξομοίωση των αλγορίθμων και το εργαλείο Xilinx ISE θα βοηθήσει στη σύνθεσή τόσο των μεμονωμένων αλγορίθμων, όσο και του multi-mode κυκλώματος. / In this diploma thesis, we will study the process of encryption and decryption. We will refer to the reasons why these processes are so popular in many fields (mathematics, trade, army, etc). A special reference will be made in the cryptographic algorithms SHA-256 and SHA-512. We will study their structure and function. Furthermore, we will discuss the two above mentioned algorithms can be operated in the same circuit. This is called multi-mode. Finally, we will use Modelsim in order to compile our algorithms and Xilinx ISE for the synthesis not only for the stand-alone algorithms, but for the multi-mode circuit, as well.

Submitted by Wagner Junior (wagner.junior@unioeste.br) on 2018-09-20T20:52:59Z No. of bitstreams: 2 Leide_Katia_Giehl_2018.pdf: 2495458 bytes, checksum: dbccdad065933b748a8722866c131fd6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-20T20:52:59Z (GMT). No. of bitstreams: 2 Leide_Katia_Giehl_2018.pdf: 2495458 bytes, checksum: dbccdad065933b748a8722866c131fd6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work explores the didactic potential of the multi-mode and multiple representations (MMR) as a teaching strategy for the teaching the theme Semiconductors and its applications in technology devices. The teaching strategy is conducted through the construction and application of a didactic workshop composed of four meeting addressing the content of Modern and Contemporary Physics - Semiconductors applied to technology. The MMR teaching strategy aims to provide students with a range of opportunities to construct, refine and deepen scientific knowledge. So that if a student can not understand a concept in relation to a particular representation, another representation may be more effective and engaging. The main goal of this work is to evaluate the potential of the teaching strategy of the MMR for the teaching of Modern and Contemporary Physics. In order to reach this goal, it was investigated how the conceptual evolution of the students takes place under the multirepresentational activities by means of some diagnostic evaluations. In order to find elements that fulfill our objectives, we have opted for the data analysis divided into two parts. First we observe if there is some conceptual evolution of the students about the main physical concepts, and then analyze how this conceptual evolution takes palce during the workshop period. Data analysis was develope using content analysis technique and interpreted under the conceptual change model. The data analysis provided us with indications that there was a conceptual evolution of the students who participated of the workshop, being this evolution the result of the variety of multirepresentational activities that, taked together, contributed to the didatic functions of the MMR. / Neste trabalho, explora-se o potencial didático da estratégia de ensino baseada nos multimodos e múltiplas representações (MMR) para o ensino de Semicondutores e suas aplicações na tecnologia. A estratégia de ensino é proposta a partir da construção e aplicação de uma oficina didática dividida em quatro encontros, desenvolvida com um grupo de alunos da terceira série do ensino médio com abordagem do conteúdo de Física Moderna e Contemporânea (FMC) – Os semicondutores aplicados à tecnologia. A estratégia de ensino dos MMR tem por objetivo proporcionar aos alunos uma gama de oportunidades para construir, refinar e aprofundar o conhecimento científico de forma que, se um aluno não consegue entender um conceito em relação a uma representação particular, outra representação pode ser mais eficaz e envolvente. O trabalho tem por objetivo avaliar as potencialidades da estratégia de ensino dos MMR para o ensino da FMC. Ao longo da oficina, é investigado como se dá a evolução conceitual dos estudantes a partir das atividades multirrepresentacionais e das avaliações diagnósticas propostas. Para buscar elementos que cumpram os objetivos propostos, optou-se por fazer a análise de dados dividida em duas partes. Primeiramente observamos se houve evolução conceitual dos estudantes, para então analisar como ocorreu esta evolução no decorrer da oficina. A análise de dados foi desenvolvida através da técnica de análise de conteúdo e interpretada através do modelo de mudança conceitual. A análise de dados no trouxe indícios de que houve evolução conceitual dos estudantes participantes da oficina, a qual é fruto da variedade de atividades multirrepresentacionais desenvolvidas que, em conjunto, contribuíram com as funções didáticas dos MMR.

In den vergangenen Jahrzehnten konzentrierte sich das Operations Management auf Optimierungsstrategien, insbesondere wurden Meta-Heuristiken für das komplexe, kombinatorische Problem der ressourcenbegrenzten Ablaufplanung erforscht. In einfachen Worten gehört dieses Problem zu den NP-schweren Problemen, die einen derart großen Lösungsraum besitzen, der mittels Enumerationverfahren rechnerisch unlösbar ist. Daher erfordert die Exploration von optimalen Lösungen andere Methoden als Zufallssuchverfahren. Solche Suchalgorithmen in Meta-Heuristik starten mit einer oder mehreren Ausgangslösung und erkunden den Suchraum nach optimalen Lösungen. Jedoch stellen die existierenden Forschungsansätze zur Lösungssuche nur diejenigen Lösungen bereit, die ausschließlich unter den gegebenen Eingangsbedingungen optimal sind. Diese Eingabebedingungen definieren einen Lösungsraum, in dem alles nach Plan geht. Jedoch ist das in der Praxis sicherlich nicht der Fall. Wie wir sagen, der Wandel ist die einzige Konstante in dieser Welt. Risiken und Unsicherheiten begegnen stets im täglichen Leben. Die vorliegende Dissertation untersucht Optimierungsansätze unter Unsicherheit. Der Forschungsbeitrag ist zweigeteilt. Wie bereits gesagt, wurden Optimierungsstrategien zum Durchsuchen des Lösungsraums in den letzten Jahren stark erforscht. Obwohl es eine anerkannte Tatsache ist, dass die Verbesserung und die Leistung von Optimierungsstrategien stark mit den Initiallösungen korreliert, scheint die Literatur diesbezüglich inexistent, während zumeist auf die Entwicklung von meta-heuristischen Algorithmen wie Genetische Algorithmen und Particle-Swarm-Optimierung fokussiert wird. Die Initiallösungen werden durch simulationsbasierte Strategien entwickelt, die typischerweise gierige Regeln und ereignisbasierte Simulation nutzen. Allerdings verhalten sich kommerzielle Basis-Softwareprodukte meist als Black-Box und stellen keine Informationen über das interne Verhalten bereit. Außerdem erfordern derartige Softwareprodukte meist spezielle Architekturen und missachten Ressourcenbeschränkungen. Die vorliegende Studie diskutiert die ressourcenbeschränkte Projektplanung mit alternativen Modi und schlägt ein simulationsbasiertes Rahmenwerk vor, mit dem ein heuristisches Multi-Pass-Verfahren zur Verfügung gestellt wird. Das erweiterte Multi-Modus-Problem ist in der Lage, den Produktionsbereich in einer besseren Art und Weise nachzubilden, bei dem eine Aktivität von mehreren Ressourcen unterschiedlicher Qualifikation ausgeführt werden kann. Der vorgeschlagene Rahmen diskutiert die Leistung von Algorithmen und verwendet hierfür Benchmark-Instanzen. Das Verhalten verschiedener Projektnetze und deren Eigenschaften werden auch innerhalb des vorgeschlagenen Rahmenwerks bewertet. Darüber hinaus hilft das offene Rahmenwerk, besondere Eigenschaften von Aktivitäten zu analysieren, um deren Verhalten im Fall von Störungen zu prognostizieren. Die traditionellen Methoden der Risikoanalyse schlagen Slack-basierte Maßzahlen vor, um die Effizienz von Basisplänen zu bestimmen. Das Rahmenwerk wird weiter entwickelt, um mit diesem einen Prüfstand zu gestalten, mit dem nicht-reguläre Maßzahlen bestimmt werden können. Diese Maßnahmen werden als Robustheitsindikatoren bezeichnet und korrelieren mit der Verzögerung derartiger Multi-Modus-Probleme. Solche Leistungsmaße können genutzt werden, um die Wirksamkeit von Basisplänen zu bewerten und ihr Verhalten unter Unsicherheiten zu prognostizieren. Die Ergebnisse dieser Tests werden als modifizierte Zielfunktion verwendet, in der ein bi-objektives Leistungsmaß aus Durchlaufzeit und Robustheit eingesetzt wird, um die Effizienz der vorgeschlagenen Heuristiken zu testen. Da diese Leistungsmaße das Verhalten von Aktivitäten unter Störungen zeigen, werden diese auch genutzt, um die Formfaktoren und Puffergrößen für die Entwicklung eines stochastischen Modells zu bestimmen. Die Analyse der Projektergebnisse, durchgeführt mittels Monte-Carlo-Simulationen, unterstützt das Argument von Teilpuffern für die Modellierung von Aktivitätsdauern anstatt Ansätze mit Extrempuffern und PERT-beta-Schätzungen. / Over the past decades, researches in the field of operations management have focused on optimization strategies based on meta-heuristics for the complex-combinatorial problem of resource constrained scheduling. In simple terms, the solution for this particular problem categorized as NP-hard problem, exhibits a large search space, is computationally intractable, and requires techniques other than random search. Meta-heuristic algorithms start with a single or multiple solutions to explore and optimize using deterministic data and retrieve a valid optimum only under specified input conditions. These input conditions define a solution search space for a theoretical world undergoing no disturbance. But change is inherent to the real world; one is faced with risks and uncertainties in everyday life. The present study explores solution methodologies in the face of uncertainties. The contributions of this thesis are two-fold. As mentioned earlier, existing optimization strategies have been vigorously investigated in the past decade with respect to exploring large solution search space. Although, it is an established fact that the improvement and performance of optimization strategies is highly correlated with the initial solutions, existing literature regarding this area is not exhaustive and mostly focuses on the development of meta-heuristic algorithms such as genetic algorithms and particle swarm optimization. The initial solutions are developed through simulation based strategies mainly based on greedy rules and event based simulation. However, the available commercial softwares are primarily modeled as a black box and provide little information as to internal processing. Additionally, such planners require special architecture and disregard resource constraints. The present study discusses the multi-mode resource constrained scheduling problem and proposes a simulation-based framework to provide a multi-pass heuristic method. The extended version of multi-mode problem is able to imitate production floor in an improved manner where a task can be performed with multiple resources with certain qualifications. The performance of the proposed framework was analyzed using benchmark instances. The behavior of different project networks and their characteristics is also evaluated within the proposed framework. In addition, the open framework aids in determining the particular characteristic of tasks in order to analyze and forecast their behavior in case of disruptions. The traditional risk analysis techniques suggest slack-based measures in order to determine the efficiency of baseline schedules. The framework is further developed to design a test bench in order to determine non-regular performance measures named as robustness indicators which correlate with the delay of such cases as multi-mode problem. Such performance measures can be used to indicate the effectiveness of baseline schedules and forecast their behavior. The outputs of these tests are used to modify the objective function which uses makespan and robustness indicators as a bi-objective performance measure in order to test the efficiency of proposed heuristics. Furthermore, since these measures indicate the behavior of tasks under disruptions, they are utilized in order to determine the shape factors and buffers for the development of a stochastic model. The analysis of project outcomes performed through Monte-Carlo simulations supports the argument of partial buffer sizing for modeling activity duration estimates rather than extreme buffer approaches proposed via PERT-beta estimates.

No description available.

No / For decades, the development of the Internet was driven by the purpose of providing applications to non-mobile users. No specific Quality of Service (QoS) requirement is necessary, other than ensuring reliability in the end-to-end data transfers. As such, best effort service model was deemed more than appropriate to satisfy the users' needs. Nevertheless, the scenario has changed in the last few years. A new population of nomadic users, who requires access to Internet services regardless of their location and mode of transportation is growing, while new typologies of Internet applications are being continuously developed, in which best effort service level may no longer be adequate. The SUITED project has been devised to address the emerging issues generated by this new and challenging scenario. SUITED aims at contributing towards the design and deployment of the Global Mobile Broadband System (GMBS), a unique satellite/terrestrial infrastructure, which will ensure that nomadic users have access to Internet services with a negotiated QoS. An overview of the main results achieved in the SUITED project is provided in this article. Some of the most innovative solutions developed by the SUITED team for the joint management of global mobility and end-to-end QoS support are presented. The SUITED demonstrator platform, which was developed to validate the system specifications, is also described. Finally, the results of the experimental measurement campaigns carried out with this platform are reported.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper describes the integration activities associated with the instrumentation and telemetry system developed for an F/A-18 Hornet Flight Test program, including bench integration, avionics integration, and aircraft ground and flight checkout. The system is controlled by a Boeing Integrated Defense System (IDS) Flight Test Instrumentation designed Instrumentation Control Unit (ICU), which interfaces to an avionics pilot display and Ground Support Unit (GSU) to set up the instrumentation during preflight and control the instrumentation during flight. The system takes in MIL-STD-1553, analog parameters, Ethernet, Fibre Channel, and video, and records these with onboard recorders. Selected subsets of this data may be routed to the telemetry system, which features two RF streams, each of which contains up to four PCM streams combined into a composite by a data combiner. The RF streams are transmitted by multi-mode digital transmitters capable of PCM-FM or Shaped Offset Quadrature Phase Shift Keying (SOQPSK), with selectable Turbo-Product Code (TPC) Forward Error Correction (FEC). This paper describes integration of the system with the IDS Flight Test Integration Test Bench (ITB), production avionics integration facilities, and final aircraft ground checkout and initial flight tests. It describes results of integration activities and bench evaluation of the telemetry system.