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Relations among Multiple Zeta Values and Modular Forms of Low LevelMa, Ding January 2016 (has links)
This thesis explores various connections between multiple zeta values and modular forms of low level. In the first part, we consider double zeta values of odd weight. We generalize a result of Gangl, Kaneko and Zagier on period polynomial relations among double zeta values of even weights to this setting. This answers a question asked by Zagier. We also prove a conjecture of Zagier on the inverse of a certain matrix in this setting. In the second part, we study multiple zeta values of higher depth. In particular, we give a criterion and a conjectural criterion for "fake" relations in depth 4. In the last part, we consider multiple zeta values of levels 2 and 3. We describe one connection with the Hecke operators T₂ and T₃, and another connection with newforms of level 2 and 3. We also give a conjectural generalization of the Eichler-Shimura-Manin correspondence to the spaces of newforms of levels 2 and 3.
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The Challenges of Data Acquisition in Harsh Remote PlacesBuckley, Dave 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / In modern flight test installations there is a continuing trend to move the data acquisition closer to the sensors. As a consequence the data acquisition chassis needs to be mounted in locations that are small, inaccessible and subject to harsh environmental conditions. On top of this there are an increasing number of measurements required for each new flight test campaign. This paper discusses the challenges of designing a small lightweight data acquisition chassis which can provide hundreds of channels of measurement capability while operating in tight spaces which are exposed to fluids, high vibration and extremes of temperature. The paper suggests ways of designing and installing the data acquisition chassis in order to optimize the available installation space while mitigating the effects of the harsh environmental conditions.
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Structural, economic and environmental feasibility of plastic load-bearing walling and roofing system for low-income housingLe Roux, Franel 12 1900 (has links)
Thesis (MEng) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: The lack of adequate housing becomes an increasing concern as the human population increases, which is
not only restricted to Africa, but worldwide. With the world becoming more environmentally aware, the aim
towards more sustainable development has become more essential. This results in alternative building
technologies (ABT’s) being investigated to address the backlog in housing.
This study investigates plastic materials as structural elements in low-income housing to address the housing
backlog in a structurally stable, cost efficient and environmentally sustainable manner. The viable plastic
materials that were identified are FFC (foam-fibre composite) and WPC (wood-plastic composite) as
structural elements and EPS (expanded polystyrene) as a core infill panel.
Material parameters were obtained experimentally which were used in a numerical analysis to validate the
structural stability of a modular WPC housing unit. The experimental work includes a direct compression,
direct tension, compressive creep and a four-point bending test for the WPC. With the sandwich panels a
push-though shear and four-point bending test were done. The compressive strength of the EPS as well as a
relative bond strength of the selected adhesives was also tested. Furthermore, a comparative study was
conducted on the fire performance (fire rating), cost efficiency as well as the environmental sustainability of
three housing units constructed of FFC, WPC and block and mortar, respectively. In terms of structural
stability, a modular plastic housing unit was devised and validated by both experimental work and plastic
material investigations which showed that WPC can be used for load-bearing walling (with EPS as core infill
panel), roofing and flooring systems. From the comparative study, it was found that the fire rating of the block and mortar housing unit met the
requirements of 20 and 30 minutes for the internal and external walls, respectively, prescribed by SANS
10400-T (2011). The fire rating of the block and mortar housing unit was met in terms of integrity, insulation
and stability. The two modular plastic housing units, however, only met the fire rating in terms of integrity
and insulation, but failed to meet the requirements in terms of stability. The approach used to determine the
fire behaviour of a housing unit is not as accurate as the physical fire test, since assumptions are made in
terms of the fire properties. However, the approach gives an indication of the fire performance of a housing
unit. FFC and WPC are laminated with PVC (polyvinyl chloride) which emits hydrochloride acid (HCl), when
burning. Hydrochloride acid is a toxic gas. Thus, according to one of the minimum norms, stipulated by the
NHBRC Home Building Manual and Agrément, an adequate housing unit should not emit harmful gasses.
Although these regulations are not mandatory, in terms of this, WPC and FFC are not viable building
materials for an adequate housing unit, especially when human behaviour and smoke control are considered.
However, this aspect can be improved by adding additives to control, and in some cases prevent, smoke
production.
The comparative study also indicated that the cost efficiency of the FFC housing unit is comparable to that of
the block and mortar design. The modular WPC housing unit has a cost which is substantially greater than
that of the FFC as well as the block and mortar housing units. The modular plastic housing units, FFC as
well as WPC, typically utilise unskilled labour to construct a housing unit, which can lead to the socioeconomic
conditions of a community being improved by means of job creation. Due to the relative ease of
construction of a modular plastic housing unit as well as a construction period of approximately three days,
the demand for housing can be reached at a more rapid pace than by using conventional methods.
In terms of the environmental sustainability, the plastic materials showed less negative environmental
impacts as well as improved energy efficiency compared to the block and mortar unit. / AFRIKKANSE OPSOMMING: Die tekort aan voldoende behuising raak ʼn kommerwekkende probleem in die huidige samelewing soos die
wêreld populasie aan hou toeneem, waar hierdie probleem nie net tot Afrika beperk is nie. Soos die wêreld
meer omgewingsbewus raak, word daar gestrewe na meer volhoubare ontwikkeling in die boubedryf wat
aanleiding gee tot die ontwikkeling van alternatiewe bou tegnologieë (ABT’e) om die behuisingsagterstand
op te los.
Plastiese materiale word ondersoek vir hul gebruik as strukturele elemente in lae-inkomste behuising om die
behuisingsagterstand in ʼn struktureel stabiele-, koste effektiewe- en omgewingsvolhoubare manier op te los.
Geskikte plastiese materiale is geïdentifiseer as SVS (skuim-vesel samestelling) en HPS (hout-plastiek
samestelling) vir gebruik as strukturele elemente en uitgesette polistireen is gebruik as ʼn invul paneel.
Materiële eienskappe was eksperimenteel bepaal, wat in ʼn numeriese analise gebruik was om die strukturele
stabiliteit van ʼn modulêre HPS behuisingseenheid te verifieer. Die eksperimentele werk sluit ʼn direkte druk,
direkte trek, druk kruip en ʼn vier-punt buig toets in, wat uitgevoer is met HPS. Vir die saamgestelde paneel
was daar ʼn druk-deur skuif en ʼn vier-punt buig toets gedoen. ʼn Druk toets met die uitgesette polistireen en ʼn
relatiewe verband sterkte vir die geselekteerde gomme was ook getoets. Verder, is ʼn vergelykende studie
gedoen op die vuur uitvoering (vuurbestand waardering), koste effektiwiteit en die
omgewingsvolhoubaarheid van ʼn SVS-, HPS- en blok-en-mortel behuisingseenheid. ’n Ontwerp is bepaal en
geverifieer deur beide eksperimentele werk en analitiese ondersoeke, wat gewys het dat HPS gebruik kan
word as ʼn lasdraende muurpaneel (met uitgesette polistireen invul), so wel as ʼn dak- en vloer sisteem. Daar is gevind, vanaf die vergelykende studie, dat die vuur uitvoering van die blok-en-mortel
behuisingseenheid voldoen aan die vereiste van 20 en 30 minute onderskeidelik vir die interne en eksterne
mure, soos voorgeskryf deur die SANS 10400-T (2011). Die vuur waardering van die blok-en-mortel
behuisingseenheid het in terme van integriteit, insolasie en stabiliteit voldoen. Die twee modulêre plastiek
behuisingseenhede het erger aan die vuur waardering slegs in trems van integriteit en insolasie voldoen. Hul
het misluk in die voldoening in terme van stabiliteit. Die benadering wat gebruik was om die vuur gedrag
van ʼn behuisingseenheid te bepaal, is nie so akkuraat soos ʼn fisiese vuur toets nie. Dit is omdat vir die
benadering aannames in terme van die vuur eienskappe gemaak is. Die benadering gee egter ʼn indikasie van
die vuur uitvoering van ʼn behuisingseenheid. SVS en HPS is gelamineer met PVC (poliviniel chloried) wat hidrochloried suur (HCl) afgee wanneer dit
brand. Hidrochloried suur is ʼn giftige gas. Volgens een van die minimum norms, gestipuleer deur die
NHBRC Home Building Manual en Agrément, moet ʼn voldoende behuisingseenheid nie giftige gasse afgee
nie. Al is die regulasies nie verpligtend nie, in terme hiervan, is SVS en HPS nie ʼn uitvoerbare boumateriaal
vir ʼn voldoende behuisingseenheid nie, veral wanneer menslike gedrag en rook beheer aangespreek word
nie. Nietemin, die aspek kan verbeter word deur die byvoeging van bymiddels om die rook produsering te
verminder en in sommige omstandighede te voorkom.
Die vergelykende studie het ook gewys, dat die koste effektiwiteit van die SVS-behuisingseenheid
vergelykbaar is met die van ʼn blok-en-mortel behuisingseenheid. Die HPS-behuisingseenheid se koste is
aansienlik hoër as die van SVS-en die blok-en-mortel behuisingseenheid. Die modulêre plastiese, SVS en
HPS, behuisingseenheid maak tipies gebruik van ongeskoolde werkers om die behuisingseenhuid op te rug,
wat tot ʼn verbetering in die sosio-ekonomiese toestande in ʼn gemeenskap kan lei, deur dat dit werk skep.
Aangesien die modulêre plastiese behuisingseenheid met relatiewe gemak en in ongeveer drie dae opgerig
kan word, kan die aanvraag tot behuising vinniger bereik word, as wanner die konvensionele boumetodes
gebruik word.
In terme van omgewingsvolhoubaarheid, het die plastiese materiale minder negatiewe omgewingsimpakte en
is meer energie-doeltreffend in vergelyking met die blok-en-mortel onwerp.
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A Classification of all Hecke Eigenform Product IdentitiesJohnson, Matthew Leander January 2012 (has links)
In this dissertation, we give a complete classification and list all identities of the form h = fg, where f , g and h are Hecke eigenforms of any weight with respect to Γ₁(N). This result extends the work of Ghate [Gha02] who considered this question for eigenforms with respect to Γ₁(N), with N square-free and f and g of weight 3 or greater. We remove all restrictions on the level N and the weights of f and g. For N = 1 there are only 16 eigenform identities, which are classically known. We first give a new proof of the level N = 1 case. We then give a proof which classifies all such eigenform identities for all levels N > 1. The identities fall into two categories. There are two infinite families of identities, given in Table 7.2. There are 209 other identities, listed (up to conjugacy) in Table 7.1. Thus any eigenform identity h = f g with respect to Γ₁(N) is either conjugate to an identity in Table 7.1 or takes the form of an identity described in Table 7.2.
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Highly Active Zinc Finger Nucleases by Extended Modular AssemblyBhakta, Mital Subhash January 2012 (has links)
C2H2-zinc fingers (ZFs) are commonly found in transcription factors that code for nearly 3% of gene products in the human genome. ZF proteins are commonly involved in gene regulation during development, cell differentiation, and tumor suppression. Each "finger" is a domain composed of approximately 30 amino acids. Since the discovery of these domains over 25 years ago, several groups have contributed to the structural and biochemical knowledge to understand their DNA-binding properties. Taking advantage of the simplicity of manipulating the DNA-binding potential of a ZF, the technology has now evolved to make sequence-specific Zinc Finger Nucleases (ZFNs), Artificial Transcription Factors (ATFs), Zinc Finger Recombinases, and DNA detection tools. ZFPs have been used for various applications, ranging from regulating genes by ZF-ATFs to manipulating genomes in diverse organisms. ZFNs have remarkably revolutionized the field of genome engineering. ZFN-modified T-cells have now advanced into human clinical trials for cell-based therapies as a treatment against HIV. Despite the advances in the ZFN technology, one of the challenges in the field is obtaining effective ZFNs using publicly available tools. The traditional method of synthesizing custom ZF arrays was using modular assembly (MA). In this method, preselected ZFs from publicly available one-finger archives can be assembled modularly to make long arrays. MA of ZFNs provides a rapid method to create proteins that can recognize a broad spectrum of DNA sequences. However, three- and four-finger arrays often fail to produce active nucleases. The low success rate of MA ZF arrays was attributed to the fact that they suffer from finger-finger incompatibility referred to as context-dependent effects. However, we hypothesized that the low affinity of MA arrays was the limiting factor. The work presented in this dissertation describes our efforts at addressing these fundamental methodological challenges. We developed the Extended Modular Assembly method that overcomes the limitations of both the previous Modular Assembly. We performed a systematic investigation of number and composition of modules on ZFN activity and analyzed ZFN specificity both in vitro and in vivo. Our current experiments apply the ZFNs produced by our method to study the role of genetic variation in human disease.
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An Advanced, Programmable Data Acquisition SystemWargo, William D., Eckstein, Howard 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / The MicroDAS-1000 is an airborne Data Acquisition System (DAS) designed to meet the growing needs of airframe manufacturers for extensive test data accumulation, processing and evaluation. As such, the system has been designed with emphasis on modularity, miniaturization and ease of operator usage and expansion. The MicroDAS product line includes a series of components used as building blocks to configure systems of virtually any size. The modular design of these components allows considerable latitude to the instrumentation engineer in configuring systems for simple or complex applications. The modular concept has been extended to the design of plug-in modules for different functional requirements and system applications. All units are under software control to allow rapid reconfiguration and setup as requirements for instrumentation and data gathering change.
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Modeling of modular multilevel converters using extended-frequency dynamics phasorsRajesvaran, Shailajah 08 September 2016 (has links)
This thesis investigates modeling of modular multilevel converters (MMCs) using an averaging method known as extended-frequency dynamic phasors. An MMC can be used as an inverter or a rectifier in high voltage direct current (HVDC) system. This research develops a dynamic phasor model for an MMC operated as an inverter.
Extended-frequency dynamic phasors are used to model a system with only interested harmonics present. The developed model is capable of capturing both the low and high-frequency dynamic behavior of the converter depending on the requirements of the study to be performed.
The selected MMC model has 5 submodules per arm (6-level converter), nearest level control, capacitor voltage balancing, direct control and phase-locked loop (PLL) synchronization. With the above features, the developed dynamic phasor model is validated with electromagnetic transient model is developed using PSCAD simulation software.
The results are compared at transient and steady state with disturbances. The main computational advantage of this modeling is achieving less simulation time with inclusion of harmonics of interest. / October 2016
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Surface Modifications to Enhance the Wear Resistance and the Osseo-integration Properties of Biomedical Ti-alloyKami, Pavani 08 1900 (has links)
The current study focuses on improving the wear resistance of femoral head component and enhancing the osseo-integration properties of femoral stem component of a hip implant made of a new generation low modulus alloy, Ti-35Nb-7Zr-5Ta or TNZT. Different techniques that were adopted to improve the wear resistance of low-modulus TNZT alloy included; (a) fabrication of graded TNZT-xB (x= 0, 1, 2 wt%) samples using LENS, (b) oxidation, and (c) LASER nitriding of TNZT. TNZT-1B and TNZT-O samples have shown improved wear resistance when tested against UHMWPE ball in SBF medium. A new class of bio-ceramic coatings based on calcium phosphate (CaP), was applied on the TNZT sample surface and was further laser processed with the objective of enhancing their osseo-integration properties. With optimized LASER parameters, TNZT-CaP samples have shown improved corrosion resistance, surface wettability and cellular response when compared to the base TNZT sample.
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Modular Forms and Vertex Operator AlgebrasGaskill, Patrick 06 August 2013 (has links)
In this thesis we present the connection between vertex operator algebras and modular forms which lies at the heart of Borcherds’ proof of the Monstrous Moonshine conjecture. In order to do so we introduce modular forms, vertex algebras, vertex operator algebras and their partition functions. Each notion is illustrated with examples.
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Defining what is visually dynamic for modular assets in level design / Definition av vad som är visuellt dynamiskt för modulära assets i level designJohansson, Isabell January 2017 (has links)
The essay is about how people perceive repetition in games and how old visual rules can help designers make the right choice when they create modular objects. By understanding the relationships between contrast and affinity in the visual to create an interest for the player and understand that this exists in many areas of the visual rules such as geometric shapes, silhouettes and colors, etc. How people in the game industry approach creating modular objects while at the same time coping with the problem of obvious repetition which can make models seem boring and not visualy dynamic. And how the modular method can make it difficult to keep up the creativity when bound to certain parameters that modularity requires.
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