Dissertations / Theses: 'Building Blocks (Mechanical Design)'

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Khor, Han Chuan. "Mechanical and structural properties of interlocking assemblies." University of Western Australia. School of Civil and Resource Engineering, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0026.

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A novel way to ensure stability of mortarless structures topological interlocking is examined. In this type of interlocking the overall shape and arrangement of the building blocks are chosen in such a way that the movement of each block is prevented by its neighbours. (The methodological roots of topological interlocking can be found in two ancient structures: the arch and the dry stone wall.) The topological interlocking proper is achieved by two types of blocks: simple convex forms such as the Platonic solids (tetrahedron, cube, octahedron, dodecahedron and icosahedron) that allow plate-like assemblies and specially engineered shapes of the block surfaces that also allow assembling corners. An important example of the latter so-called Osteomorphic block is the main object of this research with some insight being provided by numerical modelling of plates assembled from tetrahedra and cubes in the interlocking position. The main structural feature of the interlocking assemblies is the need of the peripheral constraint (for the Osteomorphic blocks this requirement can be relaxed to uni-directional constraint) to keep their integrity. We studied the least visible constraint structure internal pre-stressed cables which run through pre-fabricated holes in Osteomorphic blocks. It is shown that the pre-stressed steel cables can provide the necessary constraint force without creating appreciable residual stresses in the cables, however the points of connection of the cables are the weakest points and need special treatment. The main mechanical feature of the interlocking structures is the absence of block bonding. As a result, the blocks have a certain freedom of translational and rotational movement (within the kinematic constraints of the assembly) and their contacts have reduced shear stresses which hampers fracture propagation from one block to another. These features pre-determine the specific ways the interlocking assemblies behave under mechanical and dynamic impacts. These were studied in this project and the following results are reported. As the blocks in the interlocking structure are not connected, the main issue is the bearing capacity. The study of the least favourable, central point loading in the direction normal to the structure shows elevated large-scale fracture toughness (resistance to fracture propagation). However when the central force imposes considerable bending the generated tensile membrane stresses assist fracturing of the loaded block. Prevention of bending considerably enhances the strength therefore the most efficient application of the interlocking structures would be in protective coatings and covers. Furthermore, proper selection of the material properties and the interface friction can increase the system overall strength and bearing capacity. The results of the computer simulations suggest that both Youngs modulus and the friction coefficient are the key parameters whose increase improves the bearing capacity of topologically interlocking assemblies.

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Maldonado, Leslie Grace. "Building blocks for co-design of controllers and implementation platforms in embedded systems." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81609.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 93-95).
One of the biggest challenges in implementing feedback control applications on distributed embedded platforms is the realization of required control performance while utilizing minimal computational and communication resources. Determining such tradeoffs between control performance (e.g., stability, peak overshoot, etc.) and resource requirements is an active topic of research in the domain of cyber-physical systems (CPS). In this thesis, a setup is considered where multiple distributed controllers communicate using a hybrid (i.e., time- and event-triggered) communication protocol like FlexRay (which is commonly used in automotive architectures). Mapping all control messages to time-triggered slots results in deterministic timing and hence good control performance, but time-triggered slots are more expensive. The event-triggered slots, while being less expensive, result in variable message delays and hence poor control performance. In order to tradeoff between cost and control performance, a number of recent papers proposed a switching scheme where messages are switched between time- and event-triggered slots based on the state of the plant being controlled. However, all of these studies were based on a monotonic approximation of the system dynamics. This while simplifying the resource dimensioning problem (i.e., the minimum number of time-triggered slots required to realize a given control performance) leads to pessimistic results in terms of usage of time-triggered communication. In this thesis, it is shown that the usage of time-triggered communication (i.e., the requirement on the minimum number of time-triggered slots for a given control performance) is reduced when an accurate, non-monotonic behavior of the system dynamics is considered in the analysis. This technique is illustrated using a number examples and a real-life case study. While the focus is on communication resources in this thesis, these results are general enough to be applied to a wide range of problems from the CPS domain.
by Leslie Grace Maldonado.
S.M.

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Lemanski, Bethany I. "Designs for the manufacture of manipulable plastic DNA/RNA building blocks for learning life science." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/84400.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 93).
The subject of this thesis is the design of custom injection-molded manipulable DNA building blocks for use in a hands-on life sciences educational kit. The new design of the DNA building blocks is meant to replace the existing building blocks, which are hand-constructed from 12 existing LEGO® blocks and glued together by volunteers. The goals of the new design are to reduce the part count, increase the ease of assembly and outsource it to the end-user, and reduce dependence on the availability of LEGO components without sacrificing function and while keeping mold and production costs low. The functional requirements for the building blocks were determined through detailed conversations with the designer of the existing LEGO DNA Learning Center Set and its supplementary curriculum materials. Simple mechanical models and 3D-printed prototypes were used in an iterative design process. The part count for each building block was reduced to 3, which require 6 unique molds. Several design options for each of the three subcomponents of the DNA building blocks are presented for further assessment of mold cost and manufacturability.
by Bethany I. Lemanski.
S.B.

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Jerjas, Allan. "Building Blocks of Responsive Web Design." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-142345.

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The recent increase of smart device usability has had a profound impact on information availability and distribution. The flexibility and enhanced hardware features of these devices has amplified their capabilities. The result of their progression has produced a wide adaptation rate and thus can be found in several areas, such as government, education and financial institutions. To satisfy users employing such devices, suitable elements and structures are utilized; this inspires developers to generate content tailored for such units. Nevertheless, the sheer amount of platform specific guidelines overwhelms developers aspiring to target multiple entities. The dissimilarities continue with the physical attributes, in which diverse sizes and shapes are the foremost contributing factors. With the establishment of new web standards, the technique of responsive web design has emerged to facilitate multi-platform development. Consisting of multiple components, the design principle aims to produce device-independent content, classifying common characteristics and neglecting device specific elements. The investigation of this work concerning the essential technical aspects has yielded three major traits of the technique. This, in conjunction with the constructed prototype and the analysis of a business platform employing the design, has established an adequate summary regarding the foundation of the design, and has come to prove itself as an outstanding candidate for cross-platform development.
Den senaste tidens förbättringar av användarbarhet för smarta enheter har haft en djupgående inverkan på tillgänglighet till information och informationsspridning. Flexibiliteten och förbättrade hårdvarunära funktioner har utökat möjligheterna för dessa enheter. Utfallet av denna utveckling har utvidgat enheternas omfattning och därmed återfinns de i flera områden såsom hos myndigheter, utbildning och finansiella institutioner. För att tillfredsställa användarna som brukar enheterna appliceras lämpliga element och strukturer; detta inspirerar utvecklare att generera innehåll som är anpassat för sådana enheter. Dock överväldigar antalet plattformsspecifika riktlinjer utvecklare som strävar efter att framställa innehåll för flera enheter. Olikheterna fortsätter även med de fysiska attributen, där olika storlekar och former är de främsta skillnaderna. Med etableringen av nya webbstandarder, har tekniken följsam webbdesign kommit att underlätta utveckling för flera plattformar. Designen består av flera komponenter och syftar att producera enhetsoberoende innehåll, klassificering av gemensamma egenskaper och negligera enhetsspecifika element. Undersökningen av detta arbete kretsar kring de vitala tekniska aspekterna hos designen, där tre stora drag har identifierats. Detta, i kombination med den producerade prototypen och analys av en affärsplattform som utnyttjar designen, har en adekvat sammanfattning av designens utformning framställts. Designen har kommit att framstå som en utmärkt kandidat för plattformsoberoende utveckling.

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Warner, Kelly. "Building Blocks Retreat Center." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1.

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In a perfect world, teamwork just exists. People function harmoniously with each other & their environment. Although we do not live in a perfect world, people and environments can always change and adapt to better their relationships. The Pumphouse was abandoned 41 years after the project was completed because it no longer met the needs and performed the functions that it needed to perform. It no longer serves the same purpose that it once did. And while acknowledging its past, it must also address its new functions and become a piece of beautiful, usable architecture once more. This space will encourage visitors to break down the established barriers from their home or workplace environments and experience true, lasting teamwork. Through chance encounters, shared spaces, and large group gathering areas, guests are encouraged to interact with each other in more than the expected ways. In breaking down barriers and formal establishments, guests embark upon a beautiful process intended to change the way they interact with each other. This process of discovery-symbolized by the elements within this space- encourages the visitors to grow, discover and become enchanted- and not disappointed- by what they find.

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Buttler, David John. "Building blocks for composable web services." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180046/unrestricted/buttler%5Fdavid%5F200312%5Fphd.pdf.

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Levin, Brock. "Design, synthesis, and structure of versatile supramolecular building blocks /." Search for this dissertation online, 2005. http://wwwlib.umi.com/cr/ksu/main.

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Hwang, Seok-Ho. "Design and Construction of Nanoarchitectures Using Smart Building Blocks." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1145885525.

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NAPOLITANO, Carmela. "DESIGN AND SYNTHESIS OF NOVEL SCAFFOLDS AND BUILDING BLOCKS." Doctoral thesis, Università degli studi di Ferrara, 2009. http://hdl.handle.net/11392/2388697.

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Medicinal chemistry focuses on the aspect related to the structural design, synthesis and identification of therapeutically interesting compounds, i.e. pharmaceuticals, as well as the molecular reasons of their mechanism of action, including the understanding of the factors involved in the structure-activity relationships, absorption, distribution, metabolism, elimination and toxicity. A number of studies have appeared in the recent literature on the identification of molecular frameworks, which correspond to the minimum structural subunit, in several drugs or lead-compounds, able of providing ligand points for more than one type of bioreceptor. Since Evans first introduced the concept of “privileged structure”, privileged-based drug discovery has emerged as a fruitful approach in medicinal chemistry. Privileged scaffolds increase hit rates for biological targets of interest, leading to the discovery of other biologically active targets and generating leads with enhanced drug-like properties. Consequently, medicinal chemists value privileged structures as core scaffolds for viable starting points in exploration design and synthesis. Despite the identification of numerous recurring molecular frameworks in bioactive molecules, there is a restricted availability of privileged structures. Toward this concern, a subject of great fascination and importance, dealing with the need to identify novel chemotypes, have been addressed the studies conducted during this PhD thesis. Research into drug-like and lead-like concepts has explored a range of ideas looking at structural characteristics and physicochemical properties. The selected structures might represent potential replacements of frequently occurring structural motifs. The development of efficient methodologies for the synthesis of the identified compounds has provided the suitable tools to open up an investigation about the behaviour of such a kind of molecules towards biological systems.

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Andersson, Niklas. "Design of Integrated Building Blocks for the Digital/Analog Interface." Doctoral thesis, Linköpings universitet, Elektroniksystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112215.

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The integrated circuit has, since it was invented in the late 1950's, undergone a tremendous development and is today found in virtually all electric equipment. The small feature size and low production cost have made it possible to implement electronics in everyday objects ranging from computers and mobile phones to smart prize tags. Integrated circuits are typically used for data communication, signal processing and data storage. Data is usually stored in digital format but signal processing can be performed both in the digital and in the analog domain. For best performance, the right partition of signal processing between the analog and digital domain must be used. This is made possible by data converters converting data between the domains. A device converting an analog signal into a digital representation is called an analog-to-digital converter (ADC) and a device converting digital data into an analog representation is called a digital-to-analog converter (DAC). In this work we present research results on these data converters and the results are compiled in three different categories. The first contribution is an error correction technique for DACs called dynamic element matching, the second contribution is a power efficient time-to-digital converter architecture and the third is a design methodology for frequency synthesis using digital oscillators. The accuracy of a data converter, i.e., how accurate data is converted, is often limited by manufacturing errors. One type of error is the so-called matching error and in this work we investigate an error correction technique for DACs called dynamic element matching (DEM). If distortion is limiting the performance of a DAC, the DEM technique increases the accuracy of the DAC by transforming the matching error from being signal dependent, which results in distortion, to become signal independent noise. This noise can then be spectrally shaped or filtered out and hereby increasing the overall resolution of the system. The DEM technique is investigated theoretically and the theory is supported by measurement results from an implemented 14-bit DAC using DEM. From the investigation it is concluded that DEM increases the performance of the DAC when matching errors are dominating but has less effect at conversion speeds when dynamic errors dominate. The next contribution is a new time-to-digital converter (TDC) architecture. A TDC is effectively an ADC converting a time difference into a digital representation. The proposed architecture allows for smaller and more power efficient data conversion than previously reported and the implemented TDC prototype is smaller and more power efficient as compared to previously published TDCs in the same performance segment. The third contribution is a design methodology for frequency synthesis using digital oscillators. Digital oscillators generate a sinusoidal output using recursive algorithms. We show that the performance of digital oscillators, in terms of amplitude and frequency stability, to a large extent depends on the start conditions of the oscillators. Further we show that by selecting the proper start condition an oscillator can be forced to repeat the same output sequence over and over again, hence we have a locked oscillator. If the oscillator is locked there is no drift in amplitude or frequency which are common problems for recursive oscillators not using this approach. To find the optimal start conditions a search algorithm has been developed which has been thoroughly tested in simulations. The digital oscillator output is used for test signal generation for a DAC or used to generate tones with high spectral purity using DACs.
Den integrerade kretsen har sedan den uppfanns i slutet av 1950-talet genomgått en enorm utveckling och återfinns idag i princip i all elektronisk utrustning. Den lilla storleken och den låga produktionskostnaden har gjort det möjligt att integrera elektronik i vardagsföremål som datorer och mobiltelefoner och enklare system som till exempel smarta etiketter. Typiska användningsområden för integrerade kretsar är datakommunikation, signalbehandling och datalagring. Data lagras vanligtvis i digitalt format men signalbehandling kan utföras i både den digitala och i den analoga domänen. För att nå bästa prestanda i en krets måste signalbehandlingen delas upp optimalt mellan den digitala och analoga domänen Denna uppdelning möjliggörs med hjälp av dataomvandlare som översätter data mellan de två domänerna. En krets som omvandlar en analog signal till en digital motsvarighet kallas för en analogtill-digital-omvandlare och en krets som ovandlar digitalt data till en analog signal kallas för en digital-till-analog-omvandlare. Denna doktorsavhandling innehåller resultat från forskning gjord på dessa dataomvandlare och resultaten är sammanfattade i tre huvudkategorier. Det första bidraget är en felkorrigeringsmetod för digitaltill-analog-omvandlare, det andra bidraget är en kretsarkitektur för en energieffektiv tid-till-digital-omvandlare och det tredje bidraget är en konstruktionsmetodik för frekvenssyntes med hjälp av digitala svängningskretsar. Noggrannheten hos en dataomvandlare, med andra ord hur noggrannt dataomvandlaren kan omvandla data mellan de två domänerna, begränsas ofta av de fel som uppstår vid tillverkningen av den integrerade kretsen. En typ av fel som uppstår är att dataomvandlarens jämförelsenivåer inte blir lika stora. I frekvensdomänen kommer denna typ av fel resultera i icke önskade harmoniska frekvenser (distorsion) som begränsar dataomvandlarens noggrannhet. Om distorsion, som uppkommer då ett fel beror på dataomvandlarens insignal, begränsar dataomvandlarens prestanda kan den föreslagna felkorrigeringsmetoden omvandla distortionen till brus genom att göra felet oberoende av insignalen. Det resulterande bruset kan sedan formas spektralt eller filteras bort och därmed öka systemets totala prestanda. Den föreslagna korrigeringsmetiden har undersökts teoretiskt och denna teori har sedan verifierats med mätresultat från en kretsimplementation av en 14-bitars digital-till-analog-omvandlare som använder den föreslagna felkorrigeringsmetoden. Mätresultaten visar att metod en höjer prestandan hos dataomvandlaren för låga insignalfrekvenser då det är felen i jämförelsenivåerna som begränsar prestandan. Vid högre insignalfrekvenser är metoden mindre effektiv då andra dynamiska felkällor hos dataomvandlaren istället begränsar noggranheten. Nästa bidrag är en kretsarkitektur till en tid-till-digital-omvandlare. En tid-tilldigital-omvandlare är en särskild sorts analog-till-digital-omvandlare som omvandlar tidsskillanden mellan två signaler till en digital representation. Mätresultat från en kretsprototyp visar att den föreslagna kretsarkitekturen är både mindre och mer energieffektiv än tidigare publicerade kretslösningar. Det tredje bidraget är en konstruktionsmetodik för frekvenssyntes med hjälp av digitala svängningskretsar (oscillatorer). De digitala oscillatorerna genererar en sinusformad utsignal med hjälp av rekursiva algoritmer. Vi visar att prestandan hos digitala oscillatorer, mätt i termer av amplitud- och frekvensstabilitet, till stor utsträckning beror av starttillstånden hos oscillatorerna. Vi visar också att en del starttillstånd tvingar en oscillator att upprepa samma utsignalssekvens om och om igen, vi har då fått vad vi kallar en låst oscillator. Om oscillatorn har låst finns det inte längre någon drift i amplitud eller frekvens vilka är vanliga problem för rekursiva oscillatorer som inte använder denna metod. För att hitta de op timala startvillkoren för oscillatorerna har en sökalgoritm utvecklats. Denna algoritm har testats noggrannt i datorsimuleringar. En digital oscillator är lämplig att användas för testsignalgenerering för digital-tillanalog-omvandlare där kraven på amplitud- och frekvensstabila testsignaler är höga.

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Ayesa, Alvarez Susana. "Design and Synthesis of Amine Building Blocks and Protease Inhibitors." Doctoral thesis, Stockholm : Department of Organic Chemistry, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8038.

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Li, Haitao. "Design and syntheses of peptidomimetic building blocks and bioactive molecules /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9906483.

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Mallin, Lainey Jo. "Proxy-PET Building Blocks as a Design Element for Library Synthesis." Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1439982190.

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Jin, Jie. "Low power design for high performance wireless digital baseband building blocks /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?ECED%202009%20JIN.

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PODDA, ENRICO. "Design, synthesis and characterization of novel building blocks for supramolecular assemblies." Doctoral thesis, Università degli Studi di Cagliari, 2021. http://hdl.handle.net/11584/314060.

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The study of supramolecular systems, held together by non-covalent interactions, started with the design of novel building blocks. The target donors were then prepared by means of organic synthesis and characterized by analytical tools. Pyridyl-based ligands have been designed with various shapes, rigidity, lengths and number of donor atoms. The project was carried over by reacting the organic linkers with various complementary building blocks. When metal ions and unsaturated metal complexes were used, discrete or polymeric assemblies were obtained. Structural characterization of the products by means of Single-Crystal X-ray Diffraction (SC-XRD) was coupled with several analytical tools to investigate the properties of the final materials. In some cases, the luminescence properties of the building blocks were preserved in the final networks. In addition to the use of transition metal ions as complementary building blocks, we studied the possibility to employ carboxylic acids for the preparation of supramolecular assemblies, thus forming organic co-crystals. In order to explore the versatility of the polypyridyl organic linkers in supramolecular chemistry, we decided to investigate their reactivity towards three-coordinated boron species. Cyclic-borasiloxane derivatives were reacted towards pyridyl linkers producing the first example of luminescent chiral helices prepared by B–N bond formation. Polypyridyl derivatives are also known to interact with halogens via halogen bond. Our contribute in this field was aimed to the formation of halogen-bonded supramolecular assemblies. A wide variety of products was isolated including: halogen-bonded 1D polymers, T-shaped adducts, CT adducts and organic salts featuring the presence of unprecedented polyhalides networks. Concurrently to our studies on pyridyl derivatives, we decided to design a new class of charged building blocks represented by co-facial bifluorene derivatives. A butterfly-shaped synthon belonging to these class of linkers was designed featuring four carboxylic acid functionalities. The reactivity towards metal ions is presented herein along with the structurally characterized products. The results presented in this thesis clearly promote co-facial bifluorenes as promising candidate for future supramolecular assemblies for sensing applications.

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Eickert, Gunter Erick. "Using Modular Preformed DNA Origami Building Blocks to Fold Dynamic 3D Structures." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397742084.

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Madge, Jim. "Optimising the design of building blocks for self-assembly of discrete clusters." Thesis, Durham University, 2017. http://etheses.dur.ac.uk/12378/.

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Self-assembly is the spontaneous organisation of matter into an ordered state. Significant progress has been made in the fabrication of synthetic components for self-assembly, opening up routes to building blocks for the production of functional materials and nanomachines. The information required to assemble a target structure can be encoded into the building blocks. For assembly of an equilibrium state, the target must be thermodynamically stable and the pathway must avoid kinetic traps. The design of building blocks must address both these requirements. In this work a generic model is introduced which, through an explicit representation of interactions, is able to express many approaches to self-assembly. The model consists of hard cubic particles, whose faces are patterned with attractive patches. A hybrid, dynamical Monte Carlo protocol is developed to simulate self-assembly of such inhomogeneous systems efficiently, accounting for both internal rearrangements and relative diffusion rates of aggregates. Using this single model, different self-assembly strategies are assessed, ranging from simple approaches with only one type of building block, to more complex strategies using multiple components and hierarchical paths. The important case of fully addressable targets, where all components of the structure are unique and have a specific location, is then examined in more detail. Firstly, a new metric is introduced to quantify the problem of competition between partly assembled fragments, which is a prominent source of kinetic traps in addressable clusters. Principles are established for minimising this problem. Secondly, a scheme for globally optimising the interactions amongst a set of particles is developed to maximise the performance of building blocks of a given complexity. This also makes it possible to determine the level of complexity required for a given target to assemble reliably. The computational tools and general principles established in this work should be applicable in a wide range of self-assembly problems.

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Ali, Rahman. "Design of Building Blocks in Digital Baseband Transceivers for Body-Coupled Communication." Thesis, Linköpings universitet, Elektroniksystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-110562.

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Advances in communication technologies continue to increase information sharing among the people.~Short-range wireless networking technologies such as Bluetooth or ZigBee, which are mainly used for data transfer over short range, will, however, suffer from network congestion, high power consumption and security issues in the future. The body-coupled communication (BCC), a futuristic short-range wireless technology, uses the human body as a transmission medium. In BBC channel, a small electric field is induced onto the human body which enables the propagation of a signal between communication devices that are in the proximity or direct contact with the human body. The direct baseband transmission and simple architecture make BCC an attractive candidate for a future short-range wireless communication technology in particular applications such as body area network. The main focus of this thesis is on the design and implementation of digital baseband transmitter and receiver for the body-coupled communication. The physical layer (PHY) implementation of the digital baseband transmitter and receiver is inspired from the IEEE 802.3 Ethernet transmission protocol. The digital design is implemented at RTL level using hardware description language (VHDL). The functionality of the digital baseband transmitter and receiver is demonstrated by developing data transfer application layers.

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Foschi, F. M. "DESIGN AND SYNTHESIS OF ALPHA-AMINO ACID AND MORPHOLINO `CHIMERA' BUILDING-BLOCKS." Doctoral thesis, Università degli Studi di Milano, 2010. http://hdl.handle.net/2434/150054.

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SCUOLA DI DOTTORATO IN SCIENZE E TECNOLOGIE CHIMICHE AA 2009/2010 XXIII CICLO Chimica Industriale Dottorando: Foschi Francesca Matr.R07809 Tutor: Prof. Dario Landini Co-Tutor: Dr. Michele Penso Design and synthesis of -amino acid and morpholino ‘chimera’ building-blocks Non-natural quaternary α-aryl-α-amino acids are of great interest for their potential intrinsic bioactivity.1 here we reported the stereoselective conversion of a series of N-aryl-sulphonyl-α-amino acid t-butyl esters into the corresponding N-alkyl-α-aryl-α-amino esters. These α-quaternary compounds are obtained with good enantioselectivities (ee up to 98%) and high yields. This methodology has been applied to the transposition of both cyclic tertiary sulfonamide esters2 (i.e. proline derivatives) and open chain secondary compounds.3 These latter, in the first step, are N-alkylated and then rearrange to the target products. This protocol has also been applied to the degradative rearrangement of a series of arylsulfonamido esters bearing on the aromatic ring different electron withdrawing groups. The high enantioselectivity reached in this process, indicates that the stereochemical information is transferred from the N-alkylated sulfonamide A to the final rearranged product 2 via a chiral non-racemic enolate B. 4,5,6 This intermediate, through a Re-face attack, evolves into a chiral spiro-Meisenheimer complex that, in turn, undergoes the stereoselective S-Cα migration of the aryl group, with loss of sulphur dioxide. As a second part of this PhD work, we improved a synthesis of 2,6-disubstituted morpholines by the double and consecutive oxirane ring-opening under SL-PTC, followed by regioselective conversion of only one hydroxy group into a leaving group. Our background in the synthesis of 2,6-disobstituted morpholines, made us focus our attention on improving a chemical synthesis of morpholino monomer alternative to the Summerton approach, who is the sole known synthesis.

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Scheinman, David Eliot. "Discrete event simulation and production system design for Rockwell hardness test blocks." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55233.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 41).
The research focuses on increasing production volume and decreasing costs at a hardness test block manufacturer. A discrete event simulation model is created to investigate potential system wide improvements. Using the results from the simulation a production work-cell is proposed that will allow a single worker to operate 7 machines at a rate that exceeds existing production rates. This results in the workforce being reduced by a factor of four while reducing product lead-time by 30% and increasing throughput by 50%.
by David Eliot Scheinman.
M.Eng.

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Bilgic, Bora. "Design And Synthesis Of New Supramolecular Building Blocks Based On Oligo-bodipy Dyes." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/2/12609365/index.pdf.

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We have designed and synthesized a fluorescent, self-assembled molecular square containing a highly fluorescent well known flurophore boradiazaindacene (BODIPY) dye. Pt(II) complexes were used to hold together BODIPY derivatives and give the right angle to form the square structure. Usage of BODIPY fluorophore is very important on such structures because its variety of superior properties. BODIPY is a well studied fluorophore in our group and it is known that this self assembled square can be easily modified to any area of use it is needed.

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IOTTI, LORENZO. "Design of mm-Wave Local Oscillator Building Blocks for Next-Generation Mobile Backhaul." Doctoral thesis, Università degli studi di Pavia, 2017. http://hdl.handle.net/11571/1203365.

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Point-to-point wireless links in the E-Band (71-76GHz and 81-86GHz bands) can provide high-data-rate, easily-deployable, cheap and flexible backhaul solutions, important enablers for the mobile network evolution towards 5G. The development of CMOS/BiCMOS integrated transceivers for E-Band backhaul applications can help reducing the cost and footprint of the equipment, but presents design challenges, mostly related to the use of spectrally-efficient high-order modulations, which mandate high linearity and low phase noise. In this dissertation, local-oscillator generation requirements for E-Band backhaul applications are addressed. Phase-noise specifications for the frequency synthesizer are identified, and custom analog building blocks, namely a VCO and a frequency quadrupler, are proposed. The blocks have been designed in 55nm BiCMOS technology,and measurement results on test chips are presented. A noise-scalable multi-core oscillator is proposed as a key block of the frequency synthesizer. It achieves ultra-low phase noise performance, and allows to trade noise and power consumption according to system requirements, a useful feature in E-Band communications. An analytical model describing the effect of mismatches on the multi-core oscillator is also presented. It provides understanding of the robustness of the proposed solution, and useful insights on in-phase coupled oscillator design. Measurement results demonstrate advances over state of the art, primarily in terms of low phase-noise performance, and show how the proposed circuits are suitable as local oscillator building blocks in direct-conversion E-Band backhaul transceivers.

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Ivasenko, Oleksandr. "Supramolecular design of hydrogen-bonded architectures via surface self-assembly of carboxylic building blocks." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97007.

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Crystal engineering deals with the design of ordered arrays of molecular building blocks and is of high importance in nanotechnology, electronics and in the pharmaceutical industry. While organic synthesis provides access to a wide range of molecules, control over their intermolecular interactions is the major challenge taken on by crystal engineering. This thesis focuses on the surface self-assembly of carboxylic acids, as a convenient model system to study general factors governing self-assembly. It is a step towards the rational design of materials with desired compositions, morphologies and functionalities.Specifically, this thesis presents a systematic investigation of hydrogen-bonded (H-bonded) assemblies of carboxylic building blocks on surfaces (i.e. 2D crystals), complemented by studies of their assemblies in bulk solid state (i.e. 3D crystals). This work provides new insights into the complex relationship between building block structures, H-bonding synthons and self-assembly outcomes using scanning tunneling microscopy (STM), X-ray diffraction crystallography and quantum-mechanical calculations. Consideration of these insights has resulted in the supramolecular design of novel self-assembled molecular networks (SAMNs), described below.To elucidate the effect of building block structure on self-assembly, architectures formed by cyclic homo-dimers of carboxylic groups (i.e. structures containing the R22(8) synthon) are analyzed. Results are given in the form of case-studies covering formation of H-bonded macrocycles, chains, ladders, rotaxanes, catenanes and various 2D and 3D nets. Similar analyses of other H-bonding carboxylic acid assemblies are used to highlight the most important aspects of the carboxylic group's supramolecular reactivity, as well as the applications thereof.A detailed study of the surface co-assembly of trimesic acid (TMA) with n-alcohols is presented. Investigating this single system allows for the observation of a wide variety of phenomena that were previously only studied separately, and on structurally different systems. This enables relevant comparisons between molecular structure and the many factors governing self-assembly at the liquid-solid interface. The periodicity and fine structure of the TMA-alcohol SAMN is conveniently modulated by varying n-alcohol length and parity, representing an important step towards rational molecular nanopatterning of surfaces using the principles of crystal engineering.Relationships between building block structures and the stability of resulting carboxylic homosynthons (viz. the cyclic dimer R22(8), the trimer R33(12) and the hexamer R66(24)) are established through a combination of empirical observations and quantum-chemical calculations. Thus, formation of specific homosynthons is found to depend strongly upon steric intermolecular interactions, as well as upon the relative packing efficiencies of competing polymorphs. These findings allow explanation of the structure and chiral nature of the self-assembly formed by terthienobenzenetricarboxylic acid (TTBTA). Additionally, the rational design of supramolecular networks formed by the R66(24) homosynthon is demonstrated for the first time, using triethynylbenzenetricarboxylic acid (TEBTA).Finally, porous TMA networks are used as host matrices to control and study the self-assembly of new π-functional guest molecules. Specifically, two semiconducting heterocirculenes (sulflower and selenosulflower) are imaged by STM with sub-molecular resolution, enabling the study of adsorption-desorption dynamics, host-guest interactions, and stable π-π stacking architectures. The latter findings open up the possibility to form multilayers of host-guest architectures with high potential for applications in optoelectronic devices.
L'ingénierie des cristaux de solides moléculaires est un domaine en plein essor, combinant de nombreux aspects de la chimie des matériaux. Il est d'une grande importance pour l'électronique, la nanotechnologie ainsi que pour l'industrie pharmaceutique, ou il y a grand besoin de concevoir des réseaux ordonnés de molécules. Alors que la synthèse organique donne accès à un grand éventail de molécules, le contrôle des interactions intermoléculaires entre celles-ci est le défi pris en charge par l'ingénierie des cristaux. Cette thèse se concentre sur l'auto-assemblage d'acides carboxyliques en surface, en utilisant ce dernier comme modèle pour étudier les facteurs généraux gouvernant l'auto-assemblage. Cette étude constitue une étape vers la conception rationnelle de matériaux ayant des compositions, morphologies et fonctionnalités tels que souhaitées.Plus précisément, cette thèse présente une étude systématique de l'assemblage de certains blocs carboxyliques en surface (i.e. des cristaux 2D), complétée par des études de leurs assemblées à l'état solide (i.e. des cristaux 3D). Ce travail apporte un nouvel éclairage sur la relation complexe entre la structures des blocs, des synthons liées par des ponts hydrogènes et l'auto-assemblage final. Cette étude met en oeuvre la microscopie à effet tunnel (STM), la cristallographie par diffraction des rayons-X et des calculs a base de mécanique quantique. La nouvelle compréhension établie par cette étude a permis d'aboutir à la conception de nouveaux réseaux moléculaires auto-assemblees (SAMNs), décrit ci-dessous.Pour élucider l'effet de la structure des blocs sur l'auto-assemblage, les architectures formées par des homo-dimères de groupes carboxyliques (c'est-a-dire par des structures contenant le synthon R22(8)) sont analysées. Les résultats sont donnés sous la forme d'études de cas, portant sur la formation de macrocycles (liées par des ponts hydrogènes), de chaînes, d'échelles, de rotaxanes, de caténanes et de divers filets en 2D et en 3D. Des analyses similaires d'autres ensembles d'acides carboxyliques sont utilisés pour mettre en évidence les aspects les plus importants de la réactivité supramoléculaire du groupe carboxylique, ainsi que de l'utilité de celle-ci.Une étude détaillée du co-assemblage de l'acide trimésique (TMA) avec des n-alcools est présenté. La recherche complétée sur ce système permet l'observation d'un grand éventail de phénomènes n'ayant été qu'étudiés séparément. Entre autre, cela permet des comparaisons pertinentes entre structure moléculaire et les nombreux facteurs qui régissent l'auto-assemblage à l'interface liquide-solide. La structure fine et la périodicité du SAMN TMA-alcool est modulée simplement, en faisant varier la longueur et la parité des n-alcools. Ceci représente une étape importante vers la nanostructurisation rationnelle des surfaces avec des molécules, en utilisant les principes de l'ingénierie des cristaux.Les relations entre les structures des blocs et la stabilité des homosynthons carboxyliques qui en resultent (à savoir le dimère cyclique R22(8), le trimère R33(12) et l'hexamère R66(24)) sont établies par une combinaison d'observations empiriques et de calculs émanant de la chimie quantique. Ainsi, la formation d'homosynthons spécifiques se trouve à dépendre fortement des interactions stériques intermoléculaires, ainsi que de l'efficacité relative des polymorphes qui résultent de l'assemblage. Ces résultats permettent l'explication de la structure et de la nature chirale de l'auto-assemblage formé par l'acide terthienobenzenetricarboxylic (TTBTA). En outre, la conception rationnelle des réseaux supramoléculaires formés par l'homosynthon R66(24) est démontré pour la première fois, a l'aide de l'acide triethynylbenzenetricarboxylic (TEBTA).Enfin, les réseaux poreux TMA sont utilisées comme matrices d'accueil pour contrôler et étudier l'auto-assemblage de nouvelles molécules π-fonctionnelles.

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Ng, Chik-wai, and 吳植偉. "Design techniques of advanced CMOS building blocks for high-performance power management integrated circuits." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45896926.

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Herder, Martin. "Improving the design of diarylethene photoswitches and their exploitation as remote-controlled building blocks." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17478.

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Photochrome Diarylethene haben die einzigartige Eigenschaft, dass ihr pi-Elektronensystem durch den Isomerisierungsprozess stark verändert wird, was zu einer Verschiebung von HOMO und LUMO Niveaus führt. Zur Verwendung von Diarylethenen zur Steuerung von Funktionen, wie katalytische Aktivität, supramolekulare Assoziation oder Ladungstransport, muss die photochrome Baueinheit den spezifischen Anforderungen angepasst und ihre Schalteigenschaften, die Ermüdungsresistenz sowie das Ausmaß der elektronischen Modulation verbessert werden. In dieser Arbeit wird durch systematische Variation der zentralen Komponenten und der terminalen Substituenten eine Serie von elektronisch modulierten Diarylethenen synthetisiert. Durch umfangreiche Untersuchungen zur photochemischen Bildung eines Nebenprodukts, ein Prozess der bei nahezu allen Diarylethenen auftritt, können Strukturen identifiziert werden, die über eine große Zahl von Schaltzyklen ermüdungsresistent sind und gleichzeitig eine hohe strukturelle und synthetische Flexibilität bieten. Weiterhin erlauben bestimmte Substitutions-muster die orthogonale elektro- und photochemische Steuerung des Isomerisierungsprozesses. Durch geeignete strukturelle Modulation wird die Nebenproduktbildung bei der oxidativen Zyklisierungsreaktion unterdrückt und es kann ein Einblick in den zugrunde liegenden Mechanismus erhalten werden. Der Einfluss verschiedener Substitutionsmuster auf das pi Elektronensystem von Diarylethenen wird untersucht und es wird gezeigt, dass HOMO und LUMO Level über einen großen Energiebereich moduliert werden können. Die so erhaltenen elektronisch modulierten Diarylethene werden als aktive Elemente in Licht gesteuerten organischen Dünnschichttransistoren eingesetzt. In einem weiteren Ansatz die schaltbaren elektronischen Änderungen in Diarylethenen zu nutzen, wird ein potentiell katalytisch aktives Guanidin mit der photochromen Einheit gekoppelt, mit dem Ziel einen photoschaltbaren Organokatalysator zu konstruieren.
Photochromic diarylethenes have the unique property that the pi-electronic structure of their molecular backbone significantly alters during the isomerization process, resulting in a marked shift of HOMO and LUMO levels. In order to employ diarylethenes for the reversible light-controlled manipulation of specific functions, such as catalytic activity, association behavior, or charge transport, the photochromic scaffold has to be improved in terms of its switching efficiency, fatigue resistance, and extent of electronic modulation. In this work, a series of diarylethenes is synthesized by systematically varying the constituents of the hexatriene core and the terminal substituents. By the in-depth characterization of the photochemical reaction to a by-product, an ubiquitous phenomenon of diarylethene photochromism, fatigue resistant structures are identified that allow for the reliable operation of the photochrome over many switching cycles and at the same time guarantee a high degree of structural and synthetic flexibility. Furthermore, a distinct substitution pattern is found to enable the orthogonal electro- and photochemically mediated isomerization of diarylethenes. By proper modulation of the structure, the fatigue observed during the oxidative cyclization reaction is minimized and insights into the underlying mechanism are gained. The impact of different substitution patterns on the pi-electronic structure of the diarylethene core is studied and it is shown that HOMO and LUMO levels can be tuned over a broad energy range. The electronically tuned diarylethenes are applied as active building blocks in light-controllable organic thin film transistors. In a second approach to exploit the isomerization induced electronic modulations, a potentially catalytically active guanidine unit is coupled to the diarylethene core in order to construct a photoswitchable organocatalyst.

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Yeh, Alice Su-Chin. "Design and thermal modeling of a residential building." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54544.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 37).
Recent trends of green energy upgrade in commercial buildings show promise for application to residential houses as well, where there are potential energy-saving benefits of retrofitting the residential heating system from single-zone to multi-zone temperature control. The objective of this thesis is to design a physical model to simulate the thermal profile of a residential building with a conventional single-zone central heating system. A scale model of a 2-story house was designed and constructed at 1/20 of the length scale of an average lifesize house, with an external heater and five temperature sensors connected to Vernier LabPro for data acquisition. Comparison between scale model prediction and experimental result shows similarity in steady state values for temperature and characteristic heating/cooling time constants. This thesis is an important first step toward designing a model house for multi-zone heating studies.
by Alice Su-Chin Yeh.
S.B.

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27

Hilding, Amanda. "Evaluation and Consequences Analysis of a Manual Shifter with Modular Design." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5202.

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Subcontractors in the automotive industry, have a lot of pressure to bring down costs and to deliver products that are effective, optimized and qualitative. The main purpose of this study is to guide and conduct the first step in the project Standard Building Blocks with modular design, within the business area, manual shifter. The project is directly presented by Kongsberg Automotive, a well-known subcontractor of the automotive industry. The aim of the project is to develop a standard manual shifter with modular design containing standard building blocks. Five different components have been selected in the manual shifter for this study. In each component, there are several concepts on how to design that specific component. The target of the study is to evaluate and analyze the concepts and based on the results decide which of the concepts to be standard building blocks. The study identifies, evaluates and analyses the consequences of the project Standard Building Blocks for the chosen concepts. The results from the study show that some concepts have a greater tendency to form standard building blocks when compared to others. In the study it was proven that non-measurable values have the same significance as the measured values. The results also show that the most suitable concepts depends on the customers’ specifications. The consequence analysis presented many consequences of what an implementation of standard building blocks may imply, from the advantages to possible risk elements. Through the consequence analysis the studied company can become more prepared for the future.
Underleverantörerna inom fordonsindustrin har en stor press när det kommer till hålla nere kostnader och att leverera effektiva, optimerade och kvalitativa produkter. Huvudsyftet med studien är att guida och genomföra det första steget i projektet Standard Building Blocks med modulär design, inom affärsområdet, manuella växelreglage. Projektet är direkt framtaget av Kongsberg Automotive, en välkänd underleverantör inom fordonsindustrin. Målet med projektet är att utveckla en standard manuell växelreglage med modulär design innehållande standard building blocks. Fem olika komponenter har valts ut i den manuell växelreglaget för studien. För varje komponent finns det flera koncept hur den specifika komponenten kan designas. Målet med studien är att utvärdera och analysera koncepten och utifrån resultatet avgöra vilka av koncepten som kan bilda standard building blocks. Studien identifierar, utvärderar och analyserar konsekvenser av projektet Standard Building Blocks för de valda koncepten. Resultatet från studien visade att vissa koncept har en större tendens att bilda standard building blocks än andra. I studien blev det bevisat att icke-mätbara värden har lika stor betydelse som uppmätta värdena. Resultatet visade också att de mest lämpade koncepten beror på kundens specifikationer. Konsekvensen analysen presenter många konsekvenser av vad en implementation av standard building blocks kan innebära, från fördelar till eventuella riskfaktorer. Genom konsekvensanalysen kan det studerade företaget bli mer förberedda för framtiden.

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Torgersen, Tommy. "Configuration tool for conceptual design of an offshore supply vessel using 3D modular building blocks." Thesis, Norwegian University of Science and Technology, Department of Marine Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-6722.

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Padovan, Fabio. "Analysis and design of high performance building blocks for phased array system in BiCMOS technology." Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424338.

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Phased array systems are spreading a lot in these years due to their higher performances respect to a single antenna. These systems have been progressively more and more employedin many fields such as satellite communications, high data rate links (emerging 5G technology), military and automotive radars. Initially they where only used for military applicationsdue to their higher costs and complexity. Thanks to the technology development and the researchers efforts, these days it is possible to integrate on the same chip an entire phased array system, leading to a drastic cost reduction. The explosive growth of the applications that use the phased array approach is the motivation behind this thesis, which deals with the analysis and design of high performance building blocks for phased array systems. The first part of this work gives a brief introduction on the phased array systems illustrating the working principle, the main tasks and issues of the design related to the need for high resolution and directivity of the antennas array. The second part of the thesis is dedicated to the analysis and design of building blocks for phased array systems. More in detail, the design of VGA (variable gain amplifier) and VCO (voltage controlled oscillator) will be described. VGAs are very important in the whole system because they are responsible for the array directivity and precision in the beam forming. The impact of the VGA performance impact on the phased array functionality is hence treated and analyzed. The phase behavior when the gain setting is changed is analyzed and discussed in depth. The aim of the design is to keep the phase of the signal constant for all the gain range variation in the frequency band of the amplifier. Several phase error compensation techniques have been studied and implemented. Some X -Band SiGe VGA have been realized and measured. The performance in terms of phase error as the gain is varied out-performs the state-of-the-art. In addition to X -Band applications, some work on the upcoming 5G Communication Network has been done. A Wide Band (15 − 40 GHz) Variable Gain Amplifier has been prototyped in SiGe BiCMOS technology and a 28 GHz VGA has been implemented in a 40 nm CMOS Technology. The VCO is the other fundamental building block that we take into consideration in this thesis. In this case, we focus our attention on the phase noise, a crucial parameter that is directly related to the performance of the phased array system. An in-depth analysis on the minimization of the phase noise has been done and some K-band (i.e. 18-27 GHz) VCOs have been realized in a SiGe bipolar technology. The VCOs feature a phase noise as low as -137 dBc/Hz at 10 MHz offset from the carrier. This result out-performs the state of the art if compared to other Silicon K-band Silicon-based VCOs. Only VCOs implemented using compound semiconductor technologies show better performance in terms of phase noise. However the technology cost is in this case, dramatically higher. The work shows the feasibility of realizing high performance building blocks for phase array systems in Silicon technology. The possibility to integrate an entire phased array system on the same chip leads to a drastic cost reduction, overcoming the barrier that has stopped the development of this approach for several applications for many years. This a is crucial point for the development of next generation high data rate communication links and high precision automotive and military radars.
I sistemi Phased Array si stanno diffondendo molto in questi anni grazie alle loro elevate prestazioni rispetto alla singola antenna. Questi sistemi sono stati usati sempre più in molti campi, per esempio nelle comunicazioni satellitari, nei link ad alta velocità di trasmissione (emergente tecnologia 5G), nei radar militari e automotive. Inizialmente erano usati solo nelle applicazioni militari a causa dell’elevato costo e complessità del sistema. Grazie allo sviluppo di nuove tecnologie e allo sforzo dei ricercatori, al giorno d’oggi è possibile integrare nello stesso chip un intero sistema Phased Array, portando quindi ad una drastica riduzione dei costi. La motivazione di questa tesi è appunto la crescita esplosiva delle applicazioni che adottano l’approccio dei Phased Array, in particolare la tesi si occupa dell’analisi e progettazione di blocchi circuitali ad alte prestazioni per i sistemi Phased Array. La prima parte del lavoro consiste in una breve introduzione dei sistemi con array di antenne illustrando il principio di funzionamento gli oobiettivi e le problematiche della progettazione relazionate al bisogno di avere alta risoluzione e direttività dell’array di antenne. La seconda parte della tesi è dedicata all’analisi e progettazione di blocchi circuitali per i sistemi Phased Array. Più in dettaglio, verrà descritta la progettazione di VGA (amplificatori a guadagno variabile) e VCO (Oscillatori controllati in tensione). I VGA sono molto importanti nel sistema perche sono responsabili della direttività dell’array e nella precisione nella formazione del fascio. Nella tesi viene analizzato l’impatto delle prestazioni del VGA rispetto alla funzionalità del sistema. Viene analizzato più in particolare il comportamente della phase del segnale rispetto alla variazione del guadagno. L’obiettivo del progetto è quello di avere la fase del segnale costante per tutto il range di variazione di guadagno nella banda di frequenze dove opera l’amplificatore. Sono state studiate e implementate diverse tecniche di compensazione dell’errore di fase. Sono stati realizzati e misurati diversi VGA in banda X in Silicio Germanio. Le prestazioni in termini di errore di fase superano lo stato dell’arte. Oltre alle applicazioni in banda X è stato fatto del lavoro per l’imminente tecnologia di comunicazione 5G. E’ stato prototipato un amplificatore a guadagno variabile a ix larga banda (15 − 40 GHz) in tecnologia SiGe BiCMOS ed un VGA a 28 GHz in tecnologia CMOS 40 nm. Il VCO è un altro fondamentale blocco circuitale che abbiamo preso in considerazione in questa tesi. In questo caso ci siamo focalizzati sul rumore di fase, un parametro cruciale che è direttamente collegato alle prestazioni del sistema Phased Array. E’ stata fatta un’analisi dettagliata sulla minimizzazione del rumore di fase e sono stati realizzati dei VCO in SiGe operanti in banda K (18-27 GHz). I VCO mostrano un romore di fase che arriva a −137 dBc/Hz a 10 MHz di offset dalla portante. Questo risultato è superiore allo stato dell’arte se confrontiamo con gli altri VCO operanti in banda K e realizzati in Silicio. Solo i VCO relizzati con semiconduttori compositi hanno prestazioni migliori in termini di rumore di fase. Ad ogni modo, il costo di queste tecnologie è drammaticamente più alto. In conclusione, il lavoro dimostra la fattibilità di realizzare blocchi circuitali ad alte prestazioni per i sistemi Phased Array in Silicio. La possibilità di integrare l’intero sistema Phased Array sullo stesso chip porta ad una drastica riduzione dei costi, superando la barriera che ha fermato lo sviluppo di questo approccio in molte applicazioni negli anni precedenti. Questo è un punto cruciale per lo sviluppo della prossima generazione di comunicazioni ad alta velocità di dati e sistemi radar ad alta precisione sia militari che automotive.

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Fang, Zhen. "OXIDATIVE DEGRADATION OF LIGNIN AND INVESTIGATION OF UTILIZATION OF LIGNIN-DERIVED MATERIALS AS BUILDING BLOCKS FOR EPOXY RESINS." UKnowledge, 2019. https://uknowledge.uky.edu/chemistry_etds/110.

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Lignin, the second most abundant biopolymer on earth, is potentially a replaceable source for bulky fuels and chemical feedstocks. There have been numerous reports on methods for the oxidative cleavage of β-O-4 linkages but relatively few reports of how those methods affect other linkages that are present in lignin. We investigated how the β-1 and β-5 linkages respond under oxidative conditions proposed for lignin deconstruction based on their effect on β-O-4 linkages. Mechanochemical treatment of lignin can greatly improve the yield of monomer products and we applied a mechanochemical approach, using powerful ring-and-puck milling to promote lignin degradation. Along with similar production of monomers in a much shorter period than what we observed in previous ball-milling process, much more unexpected reactions were taking place during the current mechanochemical process. Lignin is a promising feedstock for epoxy resins since lignin-derived aromatic monomers usually bear hydroxyl and carboxyl groups. We are working on utilizing these mono-aromatic compounds and highly-functionalized-lignin as precursors for preparation of epoxy thermosets. We are interested in investigating the properties of thermosets by utilizing the actual isolated monomer streams from raw lignin. We expect to observe attractive thermal and mechanical properties from these lignin-derived epoxy thermosets compare to that of the commercialized but currently limited-used BPA-based epoxy resins.

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Yaw, Yi Xin. "Murdoch University science and computing building energy simulation & mechanical engineering green building design." Thesis, Yaw, Yi Xin (2015) Murdoch University science and computing building energy simulation & mechanical engineering green building design. Honours thesis, Murdoch University, 2015. https://researchrepository.murdoch.edu.au/id/eprint/29904/.

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Anchored in teaching, research and community engagement approaches, Murdoch University is setting up the development of a symbolic new mixed use campus precinct expansion which is listed as one of Murdoch University’s strategic plan. As stated above, a part of the strategic plan includes the development of a new Mechanical Engineering Building (MEB) in order to engage future Mechanical Engineering students. This newly proposed MEB would be designed and constructed as an extension building from the existing Science and Computing Building that is located at the Murdoch South Street campus. Hence, the major focus of this research study investigate the new Murdoch University Mechanical Engineering green building structure and design by analysing the energy consumption of the existing Science and Computing building. The annual energy consumption of the existing building is obtained through the identification of construction materials, building design and building operational activities. All this information is then simulated using Virtual Environment by Integrated Environmental Solutions (IES-VE). The outline of this IES-VE modelling tool and implementation procedures is illustrated in Chapter 3 (Methodology) and the simulation results used to identify the major sources of the energy use are included in Chapter 4 (Results). The results showed the massive energy consumption that being used in the current Science and Computing building and the annual energy consumption is broken down into different components that makes up the total energy use.Moreover, the possibilities for building energy consumption reduction are discussed and this is based on the low embodied energy building materials and low existing building operational energy reduction strategies. For the sake of achieving green star building standard, NABERS self rating tools are introduced by determining the building operational routines and its design structure. The existing building’s NABERS score will be recognised as a useful measure for the new MEB design ideas and the selection of appliances used in order to achieve the low energy building objectives. Furthermore, the structure and design of the new MEB are drafted based on the essential requirements using SketchUp drawing tool. The dimensions and working purpose of each individual floor are illustrated and reviewed. On the other hand, basic specifications of the MEB such as experimentation and research laboratory requirements, computer appliances and HVAC demands are determined in order to diagnose the NABERS rating and thus establish a new target for green building achievement. The estimated new building energy consumption is generated and possible strategies which include energy efficiency design, energy efficient technologies and renewable technologies are discussed in Chapter 5. Generally, a green building is achieved through an integration of energy efficient programs and environmentally friendly construction projects. Thus, an introduction of potential sustainable strategies is illustrated in Chapter 6 in order to develop Murdoch University into a carbon-neutral community. The potential sustainable strategies that are discussed in this thesis project included rainwater harvesting technology, wastewater treatment plants, timber prefabricated construction and green roof garden implementation. Lastly, project summary is included in Chapter 6 (Conclusion) and several recommendations are discussed that would be important to be evaluated and discussed for further improvement.

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Brown, Ashlie (Ashlie M. ). "Building KiMoSin : design requirements for kinetic interfaces in protein education." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40396.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.
Includes bibliographical references (leaves 18-19).
Design guidelines for tools to enhance protein education are developed and applied to a prototype tool. A literature search and personal experience suggest kinetic, tangible models fill the current gaps in protein education. Thirty-six personal interviews with biology instructors and students set a mandate for three design guidelines for appropriate kinetic, tangible tools. The guidelines - simplicity, accuracy, and intuition - form a simple mantra to guide protein education tool design. The guidelines are then used to develop the prototype of an educational model of kinesin, a simple and vital motor protein. Application of these guidelines should result in design that provides students an interactive medium to discover the world of proteins. The prototyped kinesin model, nicknamed KiMoSin, shows promise of fulfilling that goal.
by Ashlie Brown.
S.B.

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Cooper, Geoffrey James Tapio. "Triaminocyclohexane based ligands as building blocks in the design and construction of polynuclear transition metal clusters." Thesis, University of Glasgow, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425163.

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López, García Patricia [Verfasser], Kerstin G. [Akademischer Betreuer] Blank, Ruby May Arana [Akademischer Betreuer] Sullan, and Henrike [Akademischer Betreuer] Müller-Werkmeister. "Coiled coils as mechanical building blocks / Patricia López García ; Kerstin G. Blank, Ruby May Arana Sullan, Henrike Müller-Werkmeister." Potsdam : Universität Potsdam, 2019. http://d-nb.info/1218404760/34.

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Madan, Anuj. "Design and reliability of high dynamic range RF building blocks in SOI CMOS and SiGe BiCMOS technologies." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45853.

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The objective of the proposed research is to understand the design and reliability of RF front-end building blocks using SOI CMOS and SiGe BiCMOS technologies for high dynamic-range applications. This research leads to a comprehensive understanding of dynamic range in SOI CMOS devices and contributes to knowledge leading to improvement in overall dynamic range and reliability of RF building blocks. While the performance of CMOS transistors has been improving naturally with scaling, this work aims to explore the possibilities of improvement in RF performance and reliability using standard layouts (that don't need process modifications). The total-ionizing dose tolerance of SOI CMOS devices has been understood with extensive measurements. Furthermore, the role of body contacts in SOI technology is understood for dynamic range performance improvement. In this work, CMOS low-noise amplifier design for high linearity WLAN applications and its integration with RF switch on the same chip is presented. The LNA and switches designed provide state-of-the-art performance in silicon based technologies. Further, the work aims to explore applications of SiGe HBT in the context of highly linear and reliable RF building blocks. The RF reliability of SiGe HBT based RF switches is investigated and compared with CMOS counterparts. The inverse-mode operation of SiGe HBT based switches is understood to give considerably higher linearity.

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Luppino, Sarah P. (Sarah Palmer). "The design and synthesis of polycyclic conjugated hydrocarbons via the incorporation of bifunctional Diels-Alder building blocks." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112438.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references.
In Chapter 1, we discuss the synthetic progress, challenges, and applications of polycyclic conjugated hydrocarbons (PCHs). In particular, we explore synthetic strategies to access polycyclic aromatic hydrocarbons and nonbenzenoid oligoacenes, and also discuss synthetic efforts to stabilize, solubilize and tune the properties of these classes of molecules. In Chapter 2, we describe the synthesis and characterization of seven new linearly conjugated ladder compounds of the phenylene-containing oligoacene (POA) molecule class. Each derivative incorporates a fused four-membered-ring linkage in the acene-like backbone. Crystal packing, spectroscopic and electrochemical properties of the molecules are described. In Chapter 3, we describe the synthesis of a set of naphthazarin-containing polycyclic conjugated hydrocarbons, which were accessed through sequential Diels-Alder reactions on a tautomerized naphthazarin core. Iptycene and POA motifs were incorporated into the synthesis of these compounds. We discuss their complexation with BF₂ to achieve full conjugation across the molecular backbone, and the potential these compounds demonstrate for naphthazarin's utility in the synthesis of novel organic electronic materials. In Chapter 4, we describe the synthetic progress towards a thirteen-aromatic-ring extended POA. Two different synthetic approaches were employed, and we discuss the pros and cons of each approach to achieve the final target. In Chapter 5, we discuss a convergent synthesis of a heptiptycene PCH, its crystal stacking properties, photophysical characterizations, and its effectiveness as a selector molecule in chemiresistive sensing with single-walled carbon nanotubes (SWCNTs).
by Sarah P. Luppino.
Ph. D.

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Dal, Toso Stefano. "Analysis and Design of Injection-Locked Building Blocks for RF Frequency Generation in Ultra-Scaled CMOS Technologies." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3421554.

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This work presents the analysis and the design of injection-locked building blocks for RF frequency generation in ultra scaled CMOS technologies. The injection locked mechanism is analyzed and employed both in the sub-harmonic injection locking version and in the super-harmonic injection locking version. In the former case sub-harmonic injection locking is employed to generate the fasthopping carriers required in UWB systems for WiMedia band #6 (i.e. from 15.3 GHz to 17.4 GHz). The work is supported by analysis of the LC oscillator in presence of a multitone synchronization signal and analysis of the hopping time. Measurement results of a 90 nm CMOS prototype demonstrate the feasibility of the proposed solution, achieving the lowest power and area consumption with respect to the state of the art. In the latter case, super-harmonic injection locking is employed to a ring oscillator to realize a very compact, wideband divider topology that features low power consumption. A first test chip containing a divide-by-2 divider was realized in a 65 nm CMOS process. Measurements demonstrate a 2 to 16 GHz locking range, achieved with the lowest power and area consumptions among the state of the art solutions. In particular, the power consumption is 2 mW while the area consumption is only 130 μm^2. The same divider topology is then extended to realize a divide-by-4 divider. The divider was implemented in a 65 nm CMOS process, together with a LC VCO operating at 8 times the GSM frequency range. The combination VCO + divider was implemented to generate a low power, low area local oscillator for the GSM standard. The figure of merit of the system VCO + divider is comparable with the state-of-the-art, despite the additional power consumption due to the divider. Moreover, the silicon area of the proposed work is remarkably smaller (0.06 mm^2).
Questa tesi descrive l’analisi e la progettazione di blocchi circuitali per la generazione di segnali a radio frequenza in tecnologie CMOS ultrascalate, basati sul meccanismo dell’ “injection locking”. All’intenro della tesi il meccanismo di injection locking viene analizzato ed utilizzato sia nella sua variante di “sub-harmonic injection locking”, sia nella variante di super-harmonic injection locking”. Nel primo caso il meccanismo di sub-harmonic injection locking viene applicato ad un oscillatore LC per generare le portanti “fast-hopping”della banda #6 dello standard UWB WiMedia (i.e. da 15.3 GHz a 17.4 GHz). Il lavoro ´e stato accompagnato da uno studio teorico della risposta dell’oscillatore LC in presenza di un segnale di sincronizzazione multitono e dallo studio del transitorio di hopping. I risultati delle misure effetuate su un prototipo realizzato in un processo CMOS a 90 nm hanno dimostrato la fattibilita' della soluzione proposta, candidandola come la migliore soluzione, fra quelle presenti allo stato dell’arte, in termini di consumi di potenza e area. In meccanismo di super-harmonic injection locking e' stato invece applicato ad un ring oscillator per realizzare in forma estremamente compatta una nuova topologia di divisori di frequenza a larghissima banda e basso consumo di potenza. Un primo test chip contenente un divisore per 2 e' stato realizzato in un processo CMOS a 65 nm per dimostrare la fattibilita' della topologia proposta. Le misure hanno evidenziato un locking range da 2 a 16 GHz, ottenuto con i pi´u bassi consumi di potenza (2 mW) e area (130 μm^2) fra quelli dello stato dell’arte. In seguito la stessa topologia di divisore e' stata estesa per realizzare un divisore per 4. Il divisore e' stato implementato in un processo CMOS a 65 nm, assime ad un VCO LC operante a 8 volte il range di frequenze GSM, per generare in forma compatta e a basso consumo di potenza un oscillatore locale conforme allo standard GSM. La figura di merito del sistema oscillatore + divisore risulta comparabile con quelle dello stato dell’arte, nonostante il consumo di potenza addizionale dovuto al divisore, ma con un consumo di area, pari 0.06 mm^2, sensibilmente inferiore.

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Mandelbaum, Andrew (Andrew Joseph). "Improvements to building energy usage modeling during early design stages and retrofits." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92195.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 104-108).
A variety of improvements to the MIT Design Advisor, a whole-building energy usage modeling tool intended for use during early design stages, are investigated. These include changes to the thermal mass temperature distribution and lighting requirement calculations, the formulation of a representative day scheme to reduce the number of days that need to be simulated to find energy usage for a full year, the creation of an optimization algorithm to allow users to improve on their designs, and the addition of an algorithm to predict potential savings from retrocommissioning (RCx) using a limited set of simple inputs. Design Advisor itself is also tested for usability, speed, and accuracy using three existing buildings. The frequency of thermal mass-related calculations is reduced by finding the limits of the semi-implicit Crank-Nicolson method before it begins to return physically implausible oscillatory temperature profiles. An effort is made to speed up lighting calculations using a multivariate regression analysis in place of a multiple-reflection-based illuminance model. Representative days are formed by creating an average and two extreme weather days per month using existing climatological data, reducing the number of simulated days per year from 365 to 72 (three per month, repeated once for training). Combined, these changes lead to reductions in run time of up to 50% with roughly 10% loss of accuracy. The optimizer leverages these run time improvements to rapidly find optimal building designs given a set of input constraints. Initially, a multistep multivariate regression is used to reduce the given search space and tighten the constraints. Then, a genetic algorithm is used to find the target solution. Initial tests of this combination have led to average reductions in energy usage of 25% given 6 minutes of calculation. To extend Design Advisor's applicability to existing buildings, an algorithm for predicting potential energy savings from RCx is implemented and tested. A database of 90 buildings that have undergone an RCx process and had their resulting energy savings documented has been collected. A k-nearest neighbors algorithm is used to evaluate the potential savings of test buildings based on this data set, operating on the assumption that similar buildings (in terms of location, size, and energy usage intensity) will present similar faults or opportunities for savings. While the average savings percentage prediction error is 0.02, the root-mean-square error is 12.4, which is greater than the actual savings potential of many buildings. Model validation is performed using three existing buildings; two in the Philadelphia area and one on MIT's campus. For energy types for which no building faults or other issues were later found (as in the MIT building), final usage predictions are found to be accurate to within a mean bias error of 11.2% to 2.6%. To improve upon these accuracies, further details about key building parameters and modes of operation would be required. These studies also inform further usability improvements, including reporting site (rather than primary) energy usage and expending reported electricity usage to include loads other than lighting.
by Andrew Mandelbaum.
S.M.

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39

Tenali, Srimayi. "Design and evolution of creative capacity building program for refugee youth empowerment." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127867.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 40-41).
There are over 5,000 unaccompanied refugee minors in Greece who have fled violence from Syria, Pakistan, Afghanistan, and Iraq. In addition to pre-existing trauma and psychological challenges, living in shelters and streets has further put youth at risk of trafficking, exploitation, and substance abuse. In 2017, MIT D-Lab partnered with Faros, a Greek NGO, to develop a design workshop for the unaccompanied minors. At the end of training, they demonstrated an improved capacity to identify and solve challenges, work in teams, and recognize self-potential. Since then, this weeklong design workshop has evolved into a multi-stage, modular training program taught over several months. The purpose of this study was to identify the successes and failures of each developmental stage of this program to determine overarching trends for building a design curriculum for vulnerable youth populations. Analysis revealed that cultural significance, flexible structure, and addressing social and behavioral concerns are among the key elements for effectively reaching refugee youth. By documenting the evolution and implications of these factors, we hope to provide a baseline for future education work with this unique and vulnerable population.
by Srimayi Tenali.
S.B.
S.B. Massachusetts Institute of Technology, Department of Mechanical Engineering

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Forler, Christian [Verfasser], Stefan [Akademischer Betreuer] [Gutachter] Lucks, and Frederik [Gutachter] Armknecht. "Analysis Design & Applications of Cryptographic Building Blocks / Christian Forler ; Gutachter: Stefan Lucks, Frederik Armknecht ; Betreuer: Stefan Lucks." Weimar : Professur Mediensicherheit, 2015. http://d-nb.info/1116366231/34.

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Forler, Christian Verfasser], Stefan [Akademischer Betreuer] [Lucks, and Frederik [Gutachter] Armknecht. "Analysis Design & Applications of Cryptographic Building Blocks / Christian Forler ; Gutachter: Stefan Lucks, Frederik Armknecht ; Betreuer: Stefan Lucks." Weimar : Professur Mediensicherheit, 2015. http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150330-23764.

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Baranski, Maciej. "Optical design and developent of building blocks for a new generation of vertically integrated on-chip confocal microscopes." Thesis, Besançon, 2013. http://www.theses.fr/2013BESA2045/document.

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Les travaux de thèse concernent le design optique et le développement d’un microscope confocal miniature MEMS intégré verticalement. Différentes architectures optiques ont été proposées afin de combiner un design optique optimal aux nombreuses contraintes technologiques liées à la fabrication collective des différents blocs élémentaires du microscope sur puce. Ceux-ci, réalisés avec des technologies hybrides, sont encapsulés par assemblage vertical de wafers utilisant les technologies de soudure ≪multi-wafer≫, et permettent la construction d’un microsystème complet d’instrumentation. Un accent particulier a été émis sur la minimisation des aberrations optiques générées par les différents composants micro optiques pour permettre une résolution de mesure élevée. Pour satisfaire ces besoins, différentes briques élémentaires ont été développées : un cube semi-transparent micro-fabriqué, différentes microlentilles réfractives basées sur le micro moulage silicium et un micro-objectif réflecteur. Un montage expérimental de caractérisation dédié à l’ évaluation de la qualité de ces micro composants a également été proposé. De plus, les différents procédés de micro-usinage silicium (gravure humide anisotrope et isotrope, gravure sèche isotrope du silicium) pour la génération de micro-miroirs et de microlentilles ont été comparés. Enfin, les procédures d’assemblage vertical, incluant toutes les technologies d’interconnexion électrique ont été développées. Le travail de thèse a été réalisée dans le cadre du projet DWST-DIS ( The Development of Multi Wafer Stacking 3D Technology for Displays and Imaging MicroSystems), programme financé par le programme Inter Carnot Fraunhofer (PICF) - un projet ANR entre FEMTO-STet l’institut Fraunhofer ENAS
The thesis manuscript concerns optical design and development of a vertically integrated MEMSbasedconfocal microscope. Different optical architectures have been proposed that aim to combineoptimal optical design and the numerous technological constraints linked to the batch fabricationof the different building blocks. The latter, made by hybrid technologies, and packaged byvertical assembly using multi- wafer bonding, allow the construction of a complete microsystem forinstrumentation. Special emphasis is placed on the minimization of optical aberrations generatedby the different microoptical components to ensure good resolution of measurement. For thesepurposes, different building blocks have been developed, namely a batch-fabricated cube-typedbeamsplitter, different silicon moulded refractive microlenses and a miniature reflective objective.Dedicated characterization system for quality assessment of the fabricated micro-components wasalso developed. Moreover, different processes of silicon-based micromachining for generation ofmicromirrors and microlenses (wet anisotropic and isotropic etch, dry isotropic etch of silicon) havebeen compared. Finally, procedures of vertical assembly including all electrical interconnectiontechnologies have been developed. The thesis work was performed in the frame of the DWST-DIS(The Development of Multi Wafer Stacking 3D Technology for Displays and Imaging MicroSystems)project funded by the Programme Inter Carnot Fraunhofer (PICF) – an ANR project between FEMTO-STand ENAS - Fraunhofer Institute

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Roy, A. "Use of conformational control in the design of novel abiotic oligomers, building blocks and biomedically potential combretastatin analogs." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2013. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2159.

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Alper, Natalie B. "Early stage product design process : a case study of an educational building kit." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113504.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 35).
A Science, Technology, Engineering, and Math (STEM) kit for the assembly of a lamp was created to encourage children's interest in mechanical and electrical engineering. To ensure the lamp was intuitive and fun to use, user testing was conducted. As the user interface (UI) for the lamp was designed and developed, tests were conducted with users using a variety of prototypes ranging from paper, cardboard, and plastic to PowerPoint storyboards on the computer. By incorporating user testing throughout the process of identifying possible button layouts as well as proper lamp proportions, a final intuitive UI with a single panel of buttons was converged upon. This UI utilized one button to switch through the four possible light modes instead of having a separate button for each mode. This UI will be employed in a future prototype that will be further tested with children in the intended age range. These tests will utilize 3D printed pieces for the base and buttons, and will incorporate all the PCBs and LEDs that are intended for use in the final product.
by Natalie B. Alper.
S.B.

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Uppenkamp, Daniel Alan. "Two Fundamental Building Blocks to Provide Quick Reaction Capabilities for the Department of Defense." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1367247524.

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Xing, Kun. "Modeling, Analysis, and Design of Distributed Power Electronics System Based on Building Block Concept." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/28123.

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The basic Power Electronics Building Block (PEBB) configurations are identified and conceptual PEBB modules are constructed and tested. Using the INCA (Inductance Calculator) parasitic extraction and the Saber circuit simulation software, the microscopic relationships between the parasitics of the packaging layout and their circuit electrical effects are cross-examined. The PEBB module with advanced packaging techniques is characterized in comparison with the wire-bond module. The soft-switching techniques are evaluated for PEBB applications. The Zero-Current-Transition (ZCT) is proved better because the parasitics in the power current flow path are absorbed into the resonant soft-switching operation. This makes the PEBBs insensitive to system integration. Based on the building block concept, the discrete and large signal average models are developed for simulation, design, and analysis of large-scale PEBB-based systems. New average models are developed for half-bridge PEBB module and Space Vector Modulation (SVM). These models keep the exact information of the discontinuous SVM and the common mode component of the three-phase system. They can be used to construct the computer models of a power electronics system the same as the modularized hardware and perform time domain simulations with very fast speed. Further more, even though the system is modeled based on modularized concept on the ABC coordinates, it can be used to perform small signal analysis on the DQ coordinates as well. Based on the developed models, the system-level interactions in integrated systems are investigated. Three interaction scenarios are presented: (1) the zero-sequence circulation current in paralleled three-phase rectifiers caused by the interleaved discontinuous SVM, (2) the load and source interactions caused by unbalanced load and small signal impedance overlap, and (3) the combined common mode noise caused by both front-end PWM rectifiers and load inverters. The interaction phenomena and mitigation methods are demonstrated through hardware testbed system. The concept of dc bus conditioning is proposed. The bus conditioner is a bi-directional dc/dc converter programmed as a current controlled current source, which shunts the large signal ac current, which otherwise goes to the dc bus, into an isolated energy storage component. In addition to alleviate the source and load interactions, it increases the load impedance/decreases the bus impedance and provides more stability margins to the distribution system. The dc bus conditioner concept and its functions are demonstrated through system simulation and preliminary hardware experiment.
Ph. D.

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Wolff, Sebastien Jean. "Statically Stable Assembly Sequence Generation And Structure Optimization For A Large Number Of Identical Building Blocks." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14045.

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This work develops optimal assembly sequences for modular building blocks. The underlying concept is that an automated device could take a virtual shape such as a CAD file, and automatically decide how to physically build the shape using simple, identical building blocks. This entails deciding where to place blocks inside the shape and generating an efficient assembly sequence that a robot could use to build the shape. The blocks are defined in a general, parameterized manner such that the model can be easily modified in the future. The primary focus of this work is the development of methods for generating assembly sequences in a time-feasible manner that ensure static stability at each step of the assembly. Most existing research focuses on complete enumeration of every possible assembly sequence and evaluation of many possible sequences. This, however, is not practical for systems with a large number of parts for two reasons: (1) the number of possible assembly sequences is exponential in the number of parts, and (2) each static stability test is very time-consuming. The approach proposed here is to develop a multi-hierarchical rule-based approach to assembly sequences. This is accomplished by formalizing and justifying both high-level and mid-level assembly rules based on static considerations. Application of these rules helps develop assembly sequences rapidly. The assembly sequence is developed in a time-feasible manner according to the geometry of the structure, rather than evaluating statics along the way. This work only evaluates the static stability of each step of the assembly once. The behavior of the various rules is observed both numerically and through theory, and guidelines are developed to suggest which rules to apply. A secondary focus of this work is to introduce methods by which the inside of the structure can be optimized. This structure optimization research is implemented by genetic algorithms that solve the multi-objective optimization problem in two dimensions, and can be extended to three dimensions.

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Finch, Edward Frank. "A requisite decision model for the selection of mechanical and electrical services in buildings." Thesis, University of Reading, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329345.

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Albarhami, Bahaa Abdulhur Hatem. "Re-evaluation of the energy conservation design strategies for sustainable building mandates." Thesis, California State University, Fullerton, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10244527.

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Energy is used in buildings, industries, and transportation and has effects on people’s lives. These effects are nationwide, worldwide, and varied. The effects comprise the economy of nations, such as the United States’ dependence on foreign oil. Also, human health and environment can be effected by building energy use. On a larger scale, carbon emissions, which are directly tied to building energy use, affect the planet.

According to the Energy Information Administration report, commercial buildings consume 40 % of the total energy in the United States. Sustainable building mandates stipulate efficient and alternative uses for the limited supply of energy, but calculations for verification and validation must be achieved in order to maintain accountability and to ensure successful energy conservation strategies over time. Leadership in Energy and Environmental Design (LEED) is a certification program that is used as a benchmark for sustainable building design. A building must satisfy the minimum number of design requirements identified by the U.S. Green Building Council (USGBC) to be awarded a LEED Green Building certification. There are no future changes on certification, but there is an opportunity to recheck how a sustainable building performs during the post-occupancy operation.

According to the energy consumption data from Student Housing Energy Bill, this research will compare the predicted to actual performance for buildings that meet the LEED platinum mandate. The result of this comparison can be useful in improving the measurement process for expecting building energy consumption and developing support methodologies to help improve post-occupancy building performance.

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Urban, Bryan J. (Bryan James). "The MIT Design Advisor : simple and rapid energy simulation of early-stage building designs." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42032.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 173-177).
Simulation tools, when applied early in the design process, can considerably reduce the energy demand of newly constructed buildings. For a simulation tool to assist with design, it must be easy to use, provide feedback quickly, and allow rapid comparisons. Most existing tools do not meet these needs, usually because they were intended for modeling finalized building designs. Often there is no user interface, and it can take hours or days to prepare, run, and interpret results. Such tools are too sophisticated for design purposes. In this document the MIT Design Advisor is presented as a simple and rapid building energy simulation tool, developed specifically for architects and building designers. Conceptual building designs can be modeled quickly and without formal training. Results are interpreted graphically and displayed to the user in a simple user interface. Side-by-side comparisons of building designs can be made, allowing users to quickly learn which building components have the biggest impact on energy consumption (heating, cooling, and lighting), indoor daylight levels, and thermal comfort. User-specified building parameters are used together with local weather data to predict monthly and annual energy use. The heat transfer model used to make the energy predictions is explained in detail in this thesis. Calculation methods are given and validated. Agreement with existing models is quite good. The MIT Design Advisor is available at http://designadvisor.mit.edu.
by Bryan J. Urban.
S.M.

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